environmental science. part 1, principles of environmental science
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"Environmental Science Specialized English for Environmental Courses. Part 1, Principles of environmental science - Võ Đình Long" LINK MEDIAFIRE: https://www.mediafire.com/?p7e6vh3d7dd5omr LINK BOX: https://app.box.com/s/tam74xubbrf9nt8hgf02lfud2grbgy5lTRANSCRIPT
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VO DINH LONG
Environmental Science(Specialized English for Environmental Courses)
PART 1
PRINCIPLES OF ENVIRONMENTAL SCIENCE
Ho Chi Minh University of Industry Publishing House, 2011
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PREFACE
This book is basically the result of six years of teaching in thefield of environmental science. Some of my graduate andundergraduate students using this book have been beingengineers, practitioners, and officers. I am very grateful to themfor their patience and tolerance as it progressed from crudelectures to its present book.This book is divided into 5 chapters:
Chapter 1: Basic units of ecology.Chapter 2: Materials and nutrient cycles.Chapter 3: Humankind’s invention with nature.Chapter 4: The pollution problems.Chapter 5: Sustainable development and the future.Many problems are discussed in the book include: the
ecosystem; materials and nutrient cycles; balance of nature;progress in agriculture, engineering, and medicine; adverseeffects of people’s activities; air, water and soil pollution;pollution reduction; how the global environment faces; and themeaning of sustainable development.
Although this book contributes by one person for the purposeof teaching and reading. I am lucky to have the supports from somany people and without their helps this book would not havebeen published. While most people did not help directly on mytheme, one of them contributed in some ways towarded helpingme.
Many thanks to my colleagues at Ho Chi Minh University ofIndustry: Prof. Le Huy Ba for reading my book and offeringvaluable advice; Miss. Nguyen Le Kim Cuong and Mrs. Nguyen
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Thi Thu Thuy for using my crude lectures for their teaching, andMiss. Nguyen Thi Hong Nhung for her reading andcommending.
I would also like to thank all of them for numerous hoursthey have allowed me to spend with them in discussing mybook, confirming reading notes, and helping me with this book.
The most importantly of all, my thanks also to the editorialstaff of Ho Chi Minh University publishing house for theirpatience with me in reading, reviewing, and publishing thisbook.
Ho Chi Minh City, June 2011Author
VO DINH LONG
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CONTENTS
Chapter 1: Basic units of ecology§1. The ecosystem§2. Components of an ecosystemVocabularyQuestions
Chapter 2: Materials and nutrient cycles§1. Importance of the nutrient cycles§2. the water cycle§3. the carbon and oxygen cycle§4. the nitrogen cycle§5. the phosphorus cycle
Chapter 3: Humankind’s invention with nature§1. Balance of nature§2. Progress in agriculture, engineering, and medicine§3. Adverse effects of people’s activities
Chapter 4: The pollution problems§1. Meaning of pollution§2. Air pollution§3. Land and soil pollution§4. Radiation and its harmful effects§5. Pollution reduction
Chapter 5: Sustainable development and the future§1. The global environmental situation§2. Suistainable developmentGlossaryMetric unit conversion tablesReferences
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CHAPTER 1: BASIC UNITS OF ECOLOGY
After studying this chapter, you should be able to:
1. Define environment.
2. Define an ecosystem.
3. Identify the components of the biosphere.
4. Describe the living and nonliving components of theenvironment.
5. Explain that bacteria and fungi are agents of decay.
6. Discuss the process of photosynthesis.
7. Enumerate the important factors that affect the growth ofplants and the survival of animals.
§1. THE ECOSYSTEM
When God created the world, He said, “Let the earthproduces all kinds of plants, those that bear grain and those thatbear fruit”, and it was done. Then He also created animals,including human beings and provided light. God, therefore, sawto it that everything needed for them to live is found in the worldwhich He created. He provided spaces, ways and means by withdifferent organisms can interact with one another and with theirenvironment.
Part of the world where life operates is known as thebiosphere.
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The biosphere consists of the air (atmosphere), water(hydrosphere), and earth (lithosphere) where living thingsinteract with their environment.
When you study the interaction or relationship betweenorganisms and their environment, you are studying anecosystem. The term ecosystem refers to all the living things andthe nonliving things in a given area. It includes all the plants andanimals together with their surroundings.
Figure 1.1: The biosphere
The ecosystem of an aquarium, for example, consists of thehydrilla and others plants, fish, snails, and other aquatic animals,some of which can only be seen under the microscope. It alsoincludes sand and pebbles at the bottom. We can also includethe owner who takes care of the aquarium.
A grassland, too, is an ecosystem. This ecosystem consists ofthe grass, earthworms, insects, bacteria, soil, water, sunlight, and
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other plants and animals that live on it. The pond is anotherexample of an ecosystem.
WARM UP
The forest is a more complex ecosystem. Can you identifysome of the components of this ecosystem?
The entire earth can be thought of as an ecosystem. It has anabundance of different kinds of species of living things which,although separate by great distances, still react with one anotherand with the nonliving world.
In a forest ecosystem, interrelationships among its living andnonliving components occur. The branches and leaves of treeshelp break the force of the rain. Layers of dead leaves and twinsand branches on the forest floor soak up water and prevent rainfrom washing soil away. Little water runs off the land. The rootsof trees hold the soil and water on which they depend.Moreover, when the leaves and branches decay, they becomepart of the rich topsoil.
The soil is made up of minerals like silica and clay. Theycome from the breakdown of rocks. There are spaces betweenthe mineral particles which are filled with air and water. Rootsof plants penetrate deeper into the soil causing physical change.They loosen the tightly packed particles. Chemical change alsooccurs. The roots absorb the minerals present.
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Figure 1.2: Plant-soil relationship
There are thousands of organisms that live in the soil, likeearthworms, that decompose the dead plants and animals. Someare too small to be seen, but they all help maintain the ecologicalbalance in the soil.
Figure 1.3: Organisms in the soil
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GUIDE QUESTIONS
1. What is an ecosystem?
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2. How do the living components of an ecosystem affect thenonliving components? Give example.
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3. Can a fallen log be considered as an ecosystem? Explainyour answer.
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§2. COMPONENTS OF AN ECOSYSTEM
In the preceding section you learned what an ecosystem is.The living component is known as the biotic and the nonlivingcomponent is known as abiotic. The biotic component consists
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of plants, animals, and bacteria. The abiotic component includesall the factors of the nonliving environment such as thesubstratum, light, rainfall, nutrients, soil, and others. Both thebiotic and abiotic components are equally important in theecosystem because without one of them the ecosystem wouldnot function.
INSIGHTFULNESS
The ecosystem consists of the biotic and abiotic components.The biotic components are the plants, animals, anddecomposers. The abiotic components are the nonliving factors,such as temperature, water, and others. The abiotic affect thebiotic components and vice versa.
1. Green plants
Green plants are known as the producers. They captureenergy from the sun and together with carbon dioxide (CO2) inthe air and water (H2O) converting together those into foodenergy. Since plants are able to manufacture their own food,they are also known as autotrophs (or self-nourishing). Theseplants are able to manufacture food though the process ofphotosynthesis, which will be explained in the next section.
Green plants also take substances, such as nitrogen and sulfurfrom the environment and convert those into plant materials thatcan be used by other organisms as food. These green plantsfurther provide oxygen which is taken in by humans and animalsin the process of respiration. For these reasons, all life, whetherin the pond, forest, or grassland, depend on green plants.
You might think that green plants consist only of the trees orbig plants that you see around. The other producers are invisible
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to your eyes. These are the microscopic drifting plants which aregreater sources of food than the big plants that you can see. Wecall these microscopic plants phytoplankton. When they becometoo abundant, they can give a pond or a body of water a greencolor, it is called Eutrophication (Eutrophication is an increasein the concentration of chemical nutrients in an ecosystem to anextent that increases the primary productivity of the ecosystem).
WARM UP
Have you ever seen a pond or a lake with green surface?
GUIDE QUESTIONS
1. What are producers?………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………2. What do producers perform in an ecosystem?………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………3. What is phytoplankton?………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………
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2. Animals
Animals, or the consumers, obtain their food from plants orother animals. Because of this, they are also known asheterotrophs, which means that they feed on others and cannotmanufacture their own food, unlike the green plants.
There are three different types of consumers, namely, theherbivores, the carnivores, and the omnivores.
Figure 1.4: There are three different types of consumers
The herbivores are those that eat plants only. For example,the caterpillar that feeds on leaves is an herbivore while thesnake that eats the caterpillar is a carnivore. Omnivores eat bothplants and animals. A human being is a good example of anomnivore.
Through the process of respiration, animals combine the foodthey eat with oxygen to produce CO2 and H2O which are usedby plants in the photosynthesis process. Animals also convertthe materials of the plant bodies into the materials that make-up
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their own bodies. All the energy produced and used by animalscomes from the plants.
GUIDE QUESTIONS
1. What are consumers?
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2. What are the three types of consumers? And give oneexample for each type.
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3. Bacteria and fungi as agents of decay
Have you ever observed what happen to leaves that fall onthe ground?
After some time, the leaves wither, break down into smallerpieces, decay, and finally become part of the soil. What do youthink is responsible for this change?
WARM UP
Have you heard of the word decomposer? What do you thinkdoes a decomposer do?
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Decomposers make-up the third biotic component of theecosystem. They use the bodies of dead animals and plants fortheir food. The materials contained in these dead bodies arebroken down by the decomposers, thus they get the energy theyneed and release the minerals and other nutrients back into theenvironment for use again by other organisms. Bacteria areamong the most abundant decomposers while fungi are knownto be the fast-acting decomposers.
Decomposers are found everywhere. In the pond, they areabundant at the bottom where the remains of the dead organisms(plants and animals) settle. On land, they abound on the surfaceof the soil where the dead bodies of plants and animals arefound.
Each of the three groups of the biotic component of theecosystem - producers (plants), consumers (animals), anddecomposers (bacteria and fungi) - has its own specific functionor task to perform.
Figure 1.5: Relationship among biotic component of the ecosystem
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The work performed by an organism is known as itsecological niche, while the place where the organism lives in theecosystem is known as its ecological habitat.
GUIDE QUESTIONS
1. What are decomposers?
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2. What do decomposers perform in the ecosystem ?
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4. Nonliving factors
The nonliving factors of the environment make-up abioticcomponent of the ecosystem. These include the chemical andphysical factors in the environment, such as light, temperature,water, pH (acidity), wind, chemical nutrients, salinity (saltiness),soil, and others.
Organisms are affected by the biotic factors simultaneouslybut, of course, different species of organisms are affecteddifferently. For example, lichens may not survive whentemperature gets very high but cactus may.
Different organisms thrive in different conditions. There areanimals, like the earthworms, which favor wet condition, whileothers, like ants, prefer drier conditions. Some plants, such ascactus, grow best in sandy soil while tomatoes grow best inloamy soil.
As a whole, these environmental factors not only provideessential energy and materials but also determine the kind oforganisms that will inhabit the area. Hence, they provide theconditions necessary for the survival of the organisms.
GUIDE QUESTIONS
1. What are the components of an ecosystem?
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2. Give examples for each component of the ecosystem.
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3. What are the functions of these components?
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4. Can an ecosystem exist without one of its components?Justify your answer.
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VOCABULARY
Autotrophs: Organism that is self-nourishing; one that canproduce its own food.
Heterotroph: Organisms that feeds on others and cannotmanufacture its own food.
Biological magnification: Accumulation or increase ofchemical substances on organisms in succeeding higher trophiclevels.
Biomass: Amount of organic materials in plants or animalsfrom which energy can be derived.
Energy: Capacity to do work
Energy content: The amount of energy available for doingwork. For example, amount of energy in fuel available forpowering a motor vehicle.
Food chain: Energy pathway which proceeds from theproducers to the consumers.
Food web: Series of interrelated food chains in an ecosystem.
Pyramid of energy: Representation of the organic content ineach trophic level.
Biosphere: Portion of the earth and its environment withinwhich life in any of its form is manifested.
Photosynthesis: Process of manufacturing food by greenplants in the presence of sunlight.
Atmosphere: Layer of air surrounding the earth.
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Hydrosphere: The part of the Earth composed of waterincluding clouds, oceans, seas, ice caps, glaciers, lakes, rivers,underground water supplies, and atmospheric water vapor.
Lithosphere: The outer, rigid shell of the earth, situatedabove the atmosphere and containing the crust, continents andplates or the solid part of the earth’s surface.
Grassland biome: Community where grass is abundant whiletrees are scarce and where mostly herbivores and rodents dwell.
Carnivore: Animals that get food from killing and eatingother animals.
Herbivore: Organisms that eat plants only.
Omnivore: Organisms that consume both plants and animals
Biotic factor: Living component of the ecosystem whichincludes plants, animals, and bacteria.
Biotic potential: Reproductive capacity of the livingcomponents of the ecosystem.
Producer (autotroph): Green plant or organism that,performs photosynthesis.
Consumer: Organism that feeds on other organisms.
Decomposer (also known as microconsumer): Organismwhich breaks down nonliving organic material; example arebacteria and fungi.
Environment: Sum of all external forces and conditionsacting on an organism or a community of organisms.
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CHOOSE THE BEST ANSWER FOR THE FOLLOWINGQUESTIONS
1. The biosphere consists of ………………..
a) atmosphere
b) hydrosphere and atmosphere
c) atmosphere and lithosphere
d) atmosphere, hydrosphere and lithosphere
2. Atmosphere ………………..
a) is the air environment
b) consists of air and water
c) consists of soil and water
d) consists of soil and air
3. Hydrosphere ………………..
a) is the air environment
b) is the soil environment
c) is the water environment
d) is the water and soil environment
4. The biosphere is place where ………………..
a) living things do not interact with their environment
b) living things interact with their environment
c) nonliving things interact each other
d) living things interact each other
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5. Lithosphere is ………………..
a) The air environment
b) The water and air environment
c) The soil environment
d) The organisms and their environment
6. Studying an ecosystem concentrates on ………………..
a) the relationship between organisms and organisms
b) the relationship between organisms and theirenvironment
c) the relationship between nonliving things
d) plants and animals
7. The term ecosystem refers to ………………..
a) all the living things in a given area
b) all the living things and the nonliving things in a givenarea
c) all the nonliving things in a given area
d) the relationship between organisms and organisms
8. A grassland is an ecosystem because it consists of ………
a) the grass
b) earthworms, insects and bacteria
c) plants and animals
d) plants and animals together with their surroundings
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9. The living components of an ecosystem affect the nonlivingcomponents by …………
a) the consumption
b) the decomposition
c) the production
d) the relationship between organisms and theirenvironment
10. ……………….. are known as the biotic.
a) The nonliving components
b) The living components
c) The nonliving and the living components
d) Water and vapour water
11. The abiotic components consist of ………………..
a) plants and animals
b) factors of the nonliving environment
c) factors of the living environment
d) bacteria
12. Both the biotic and abiotic components ………………..
a) are unequally important in the ecosystem
b) are equally important in the ecosystem
c) are not important in the ecosystem
d) do not relate in the ecosystem
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13. ……………….. are known as the producers
a) Animals
b) Green plants
c) Both green plants and animals
d) Bacteria
14. ……………….. capture the energy from the sun andtogether with carbon dioxide in the air and water converttogether those into food energy.
a) Green plants
b) Animals
c) Both green plants and animals
d) Bacteria
15. Plants are known as autotrophs because ………………..
a) they are green plants
b) they are producers
c) they are able to manufacture their own food
d) they are consumers16. ……………….. can take substances from the environment
and covert those into materials that can be used by otherorganisms as food.
a) Green plantsb) Animalsc) Consumersd) Decomposers
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17. ……………….. can provide oxygen which is taken in byhumans and animals in the process of respiration.
a) Consumersb) Animalsc) Green plantsd) Decomposers
18. We call the microscopic plants phytoplankton because …..a) they give a pond or a body of water a green colorb) they are invisible to your eyesc) they are microscopic drifting plantsd) big plants
19. Green plants consist of ………………..a) treesb) big plantsc) phytoplanktond) trees, big plants and phytoplankton
20. Animals are known as heterotrophs because …………a) they obtain their food from plants or other animalsb) they are producersc) they are able to manufacture their own foodd) they are unlike the green plants
21. Consumers include ………………..a) herbivoresb) carnivores
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c) omnivoresd) herbivores, carnivores and omnivores
22. Herbivores are those ………………..a) that eat animals and plantsb) that eat animalsc) that eat plants onlyd) that are the producers
23. Carnivores are those ………………..a) that eat animals and plantsb) that eat animals onlyc) that eat plantsd) that are the consumers
24. Omnivores are those ………………..a) that eat animals and plantsb) that eat animals onlyc) that eat plants onlyd) that are the decomposers
25. A human being is ………………..a) a herbivoreb) a carnivorec) an omnivored) a producer
26. All the energy used by animals comes from ……………a) the sun
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b) the plantsc) other animalsd) the plants and other animals
27. The decomposers ………………..a) cannot use the bodies of dead animals and plants for
their foodb) can capture the energy from the sunc) can use the bodies of dead animals and plants for their foodd) can use the energy from the sun
28. Biotic components of the ecosystem include ……………a) producersb) decomposersc) consumersd) producers, decomposers and consumers
29. ……………….. is known as its ecological habitat.a) The work performed by an organismb) The place where the organism lives in the ecosystemc) The energy flowing from the sun to the organismsd) The work performed by an organism and the place
where the organism lives in the ecosystem30. The nonliving factors of the environment make up ………
a) the ecosystemb) the biotic components of the ecosystemc) the abiotic components of the ecosystemd) the ecological habitat
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31. . . . . . . . . . . . . . are the nonliving factors of the environment.a) light and temperatureb) water and pHc) wind, chemical nutrients and soild) light, temperature, water, pH, wind, chemical nutrients,
soil, etc32. Environmental factors can ………………..
a) provide essential energy and materials to organismsb) determine the kind of organismsc) provide the necessary conditions for the survival of the
organismsd) provide the essential energy, materials, conditions and
determine the kind of organisms33. Autotroph is ………………..
a) self-nourishing organismb) organisms that cannot produce its own foodc) organisms that feeds on othersd) consumer
34. Biomass are ………………..a) Amount of organic materials in plantsb) Amount of organic materials in plants and animalsc) Amount of organic materials in animalsd) Amount of organic materials in producers, consumers
and decomposers
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35. Energy pathway which proceeds from the producers to theconsumers is known as ………………..
a) food webb) food chainc) food netd) food cycle
36. Photosynthesis is ………………..a) The process of manufacturing food by green plantsb) The process of manufacturing food by animalsc) The process of manufacturing food by bacteriad) The process of manufacturing food by fungi
37. Nonliving factors include ………………..a) Temperature, light and waterb) Chemical nutrients and soilc) The physical factorsd) The chemical and physical factors.
38. Layer of air surrounding the earth is ………………..a) climateb) atmospherec) hydrosphered) stratosphere
39. The rigid shell of the earth that contains the crust andcontinents is ………………..
a) atmosphereb) lithosphere
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c) biosphered) atmosphere, lithosphere and biosphere
40. The representation of the organic contents in each trophiclevel is ………………..
a) energy contentb) food webc) pyramid of energyd) food chain
41. Organism that ……………….. is called autotroph.a) can’t produce its own foodb) can feed on the othersc) can be self-nourishingd) can’t be self-nourishing
42. Bacteria is the ………………..a) decomposerb) composerc) producerd) organism
43. The process of manufacturing food by green plants in thepresence of sunlight is called ………………..
a) phytoplanktonb) photosynthesisc) absorptiond) greenhouse effect
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44. The caterpillar is ………………..a) the carnivoreb) the omnivorec) the herbivored) the organism
45. …………… consists of the biotic and abiotic components.a) The ecological habitatb) The nonliving factorc) The living factord) The ecosystem
46. ……………. consists of plants, animals and bacteriaa) Biotic componentb) Abiotic componentc) Atmosphered) Hydrosphere
47. Organisms that feed on others and cannot manufacture itsown food are called ………..
a) autotrophb) heterotrophc) carnivored) herbivore
48. …………….. breaks down the nonliving organic material.a) Consumerb) Organism
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c) Microconsumerd) Phytoplankton
49. Underground water is a part of ………………..a) biosphereb) atmospherec) lithosphered) hydrosphere
50. Vapour water is a part of ………………..a) hydrosphereb) biospherec) atmosphered) lithosphere
51. Wolves are the ………………..a) autotrophb) carnivoresc) omnivoresd) herbivores
52. …………….. of grassland consists of grass, earthworms,insects, bacteria, soil, water, sunlight and other plants andanimals that live on it.
a) The ecosystemb) The gardenc) The greenhoused) The diversity
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53. There are thousands of …… living in the soil decomposethe dead plants and animals.
a) earthwormsb) underground waterc) organismsd) bacteria
54. The ecosystem consists of two components: biotic and ……a) hydrosphereb) lithospherec) organismd) abiotic
55. Plants are able to manufacture their own food, so they areknown as ………………..
a) heterotrophsb) autotrophsc) protectorsd) decomposers
56. Animals are called the …… because they obtain their foodfrom plants or other animals.
a) producersb) decomposersc) consumersd) autotrophs
57. Fungi are known to be the fast-acting ………………..a) producers
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b) decomposersc) consumersd) autotrophs
58. The ………. factors of the environment make up abioticcomponent of the ecosystem.
a) nonlivingb) livingc) temperatured) chemical
59. The part of the world where life operates is known ……...the biosphere.
a) likeb) thatc) asd) is
60. The term ecosystem refers … all the living and nonlivingthings in a given area.
a) tob) ofc) ind) at
61. When the leaves and branches decay, they become a part…….. the rich topsoil.
a) tob) of
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c) ind) at
62. The place …....... the organism lives in the ecosystem isknown as its ecological habitat.
a) whichb) whenc) whosed) where
63. These environmental factors not only provide essentialenergy and materials …… determine the kind of organismsthat will inhabit the area.
a) butb) thoughc) but alsod) despite
64. Temperature is ………………..a) the living factorb) the nonliving factorc) the chemical factord) the living and nonliving factors
65. Ocean is a part of ………………..a) biosphereb) atmospherec) hydrosphered) lithosphere
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66. Lithosphere is a part of ………………..a) atmosphereb) hydrospherec) biosphered) water environment
67. The place where living things interact with theirenvironment is called ………………..
a) biosphereb) atmospherec) hydrosphered) lithosphere
68. Living components are called ………………..a) abiotic
b) biotic
c) bacteriad) bacteria and human
69. Nonliving components are called ………………..a) abioticb) bioticc) bacteriad) bacteria and human
70. Green plants are ………………..a) carnivoresb) decomposers
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c) herbivoresd) producers
71. Autotrophs are ………………..a) plantsb) herbivoresc) carnivoresd) humans
72. How many layers does the atmosphere have?a) 3b) 4c) 5d) 6
73. The ocean makes up ……………….. in the hydrosphere.a) about 97%b) about 87%c) about 77%d) about 67%
74.The groundwater makes up ……………….. in the hydrosphere.a) about 2.6%b) about 1.6%c) about 0.6%d) about 0.06%
75. Identify the error underlined word or phrase of thefollowing sentence: “Decomposer make up the third bioticcomponent of the ecosystem”.
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a) decomposerb) make upc) bioticd) ecosystem
76. Identify the error underlined word or phrase of thefollowing sentence: “When the body of dead plants andanimals decompose, they are changed into nutrients throughthe action of bacteria and fungi”.
a) bodyb) decomposec) are changed intod) through
77. Identify the error underlined word or phrase of thefollowing sentence: “Green plants also take substances,such as nitrogen and sulfur from the environment andcoverted those into plant materials that can be used by otherorganisms as food”.
a) substancesb) fromc) covertedd) can be used
78. Identify the error underlined word or phrase of thefollowing sentence: “Animals combine the food they eat tooxygen to produce CO2 and H2O which are used by plantsin the photosynthesis process”.
a) combine
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b) toc) are usedd) photosynthesis process
79. Identify the error underlined word or phrase of thefollowing sentence: “There are animals, like theearthworms, which favor wet condition, while others, likeants, prefers dry condition”.
a) earthwormb) favorc) othersd) prefers
80. On the earth, the lithosphere includes ………………..a) The crustb) The uppermost mantlec) The crust and uppermost mantled) Water and air
81. The earth's hydrosphere consists of water in all forms: ….a) the ocean, underground waterb) inland seas, lakes, rivers, ice and rainc) atmospheric water vapord) the ocean, underground water, inland seas, lakes, rivers,
ice, rain and atmospheric water vapor82. An aquatic ecosystem is an ecosystem located in ………
a) body of waterb) body of soil
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c) body of aird) urban
83. Urban ecosystems are ………….. constructed by humans.a) the citiesb) townsc) urban stripsd) the cities, towns and urban strips
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CHAPTER 2: MATERIALS AND NUTRIENTCYCLES
The energy that flows into an ecosystem cannot be recycled.Once the energy is used, it is lost. But it much be constantlyrepeatedly replenished if the ecosystem is to continuouslyfunction.
The importance of chemical nutrients, however, is usedrepeatedly. They are cycled between the living and nonlivingcomponents of the ecosystem. Generally, they begin in theabiotic part of the ecosystem (water, land, and air). Then, theyenter to the bodies of plants and animals and return into theabiotic environment.
The movement of these materials and nutrients between theliving and nonliving environment clearly shows theinterrelatedness of the abiotic and biotic components in anecosystem. Among these recycled materials and nutrients arecarbon, oxygen, water, nitrogen, and phosphorus.
After studying this chapter, you should be able to
1. Identify different nutrients that can be recycled.
2. Explain the water, carbon and oxygen, nitrogen, andphosphorus cycles.
3. Discuss the importance of each of these cycles.
4. Discuss how people affect these cycles.
5. Differentiate micronutrients from macronutrients
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§1. IMPORTANCE OF THE NUTRIENT CYCLES
The energy from the sun flows to the plants goes to theherbivore that eats the plant, to the carnivore, and to the lastconsumers until the energy is lost into the ecosystem. Theenergy does not go back to the source. It cannot be used overand over again.
In contrast, when the bodies of dead plants and animalsdecompose, they are changed into nutrients through the action ofbacteria and fungi. The nutrients are stored in the abioticenvironment like the soil. The nutrients can be used again by theplants. The plants are eaten by the animals and when the animalsdie, they decompose into nutrients. These nutrients can be usedover and over again. In this way, a cycle of nutrients is formed.
The cycle of nutrients is an important process that takes placein the ecosystem. Through the cycle of nutrients, the organiccompounds found in the bodies of organisms are converted intoinorganic compounds which serve as nutrients to the otherorganisms. In both processes of energy flow and nutrient cycles,the plants provide the link by which the biotic and abioticcomponents interact with one another.
INSIGHTFULNESS
Energy cannot be recycled. When using, it is lost into theecosystem.
The nutrients in an ecosystem can be used over and overagain. They are cycled beginning from the nonlivingenvironment: air, water, and soil. Then, these substances aretaken in by the producers and are passed on through several
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consumers. They are returned to the nonliving environment bydecomposers.
Nutrients can be classified into two categories, namely, themacronutrients and the micronutrients. The macronutrients arethose that are required by the organisms in large quantities.Examples are carbon, hydrogen, oxygen, and nitrogen. Sulfur,phosphorus, and potassium are also macronutrients but areneeded by organisms in smaller quantities. The micronutrientsare needed in very small amounts. They are also essential to life.Examples are copper, zinc, iron, and boron.
The macronutrients are the major components of fats andcarbohydrates. They make-up the cell structures of plants andanimals. The cell walls of plants, for example, are made up of avery rigid substance called the cellulose. Cellulose is made up ofthese three elements with a ratio of 7.2 carbons, 1 hydrogen and8 oxygen. This substance makes the cell walls very firm andrigid. It adds strength to the plant.
Nitrogen, carbon, hydrogen, and oxygen are the buildingblocks of proteins. Phosphorus makes up many nucleic acidsand is also essential for the transformation of energy in the cells.
The micronutrients are as important as the macronutrients.Magnesium, for example, is necessary in the production ofchlorophyll.
GUIDE QUESTIONS
1. What happens to the energy from the sun when it enters toan ecosystem?
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2. What happens to the dead bodies of plants and animals inan ecosystem?
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3. Define macronutrients and micronutrients.
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4. Make a listing of micronutrients and macronutrients, andgive their functions?
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5. What are the components of cellulose?
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§2. THE WATER CYCLE
As with any cycle, the water cycle has neither beginning norend. However, it is useful to choose a starting point. Let usbegin with water vapor in the atmosphere.
a)
b)
Figure 2.1: The water cycle
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When water in the atmosphere reaches saturation (the highestamount of moisture that the air can hold), it falls as rain. Thisfalls directly to the land and bodies of water like the oceans andseas. Some runs off the surface of the land into rivers. The rainthat falls on the land is absorbed by plants through the roots anddrank by animals. Some penetrates the soil and becomes part ofthe underground water, which eventually empties into theoceans. The processes of condensation and precipitation areresponsible for the return of water from the atmosphere into theland and other bodies of water.
The water from the land and other bodies of water returns tothe atmosphere through the process of evaporation. Plants returnthe water by the process known as transpiration, while animalsdo this through respiration. Water accumulates again in theatmosphere as clouds and falls as rain.
GUIDE QUESTIONS
1. What is saturation?
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2. What is evaporation?
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3. What is respiration?
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4. Trace the pathway of the water cycle.
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§3. THE CARBON AND OXYGEN CYCLE
Much of the carbon in the environment exists in the form ofcarbon dioxide. Plants absorb this gas though the leaves and usein the process of photosynthesis. Oxygen is given off during thisprocess. Animals and other consumers obtain their food as wellas their oxygen needs from plants. In the process of respiration,the food is broken down into CO2 and water which are returnedinto the atmosphere.
When the animals and plants die, their bodies and waters arebroken down by the decomposers. In this process, CO2 isproduced and returned to the atmosphere. Sometimes deadorganisms fail to decompose quickly. When this happens, thedead bodies change to coal, oil, and gas which become fossilfuels after a long time. When burned, fossil fuels release carbondioxide into the atmosphere.
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Figure 2.2: The carbon and oxygen cycles
INSIGHTFULNESS
Carbon dioxide is present in the atmosphere from wastes,dead bodies of organisms, and fossil fuels.
Plants use CO2 in the process of photosynthesis. Animalsobtain their food from the plants and release CO2 though the
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process of respiration. Decomposers and burning also releaseCO2 into the environment.
Erupting volcanoes emit carbon dioxide. The eruption of thevolcano supplies fresh carbon to the atmosphere from the deeperpart of the interior of the earth.
Carbon dioxide combines with water and forms calciumcarbonate (CaCO3). This compound is used in the production ofshells of animals like clams and oysters. When shelledorganisms die, the calcium carbonate may dissolve or form partof carbonate rocks serve as an buffer environment and storingcarbon for many years. During the process of weathering,carbon dioxide is again released into the environment.
GUIDE QUESTIONS
1. What are the sources of carbon dioxide?
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2. What are the sources of oxygen?
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3. How is carbon released from carbonate rocks into theatmosphere?
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4. How are fossil fuels formed?
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5. What two important processes are involved in the cycle ofcarbon and oxygen? Discuss these processes.
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§4. THE NITROGEN CYCLE
Nitrogen is an element crucial to life. It is an importantcomponent of proteins and nucleic acids. The nitrogen gasconstitutes about 78 percent of the air in the atmosphere.However, it cannot be used directly by plants and animals.Plants use it in the form of nitrates.
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You inhale large quantities of nitrogen but it remains in yourbody unchanged.
Figure 2.3: The nitrogen cycle
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Nitrogen in the atmosphere is converted into nitrates in twoways: (1) by the action of lightning and (2) by action ofspecialized organisms. Electrical activity (lightning) duringthunderstorms converts nitrogen into nitrates but only a smallamount. The nitrates produced by this process fall to the earthwith the rain.
The organisms that convert nitrogen are bacteria, algae, andfungi, of which bacteria is the most important. Nitrogen-fixingbacteria directly convert nitrogen into nitrates though theprocess called nitrogen fixation. Examples of nitrogen-fixingbacteria are the Rhizobium, which live in the roots of legumeslike beans, peas, and peanuts. The association betweenRhizobium and legumes forms swollen areas within the rootscalled nodules. Nitrates are formed within the nodules. Thecompounds are then used by the plants to build proteins, orremain in the soil as fertilizers. Because of this, legumes areimportant crop rotation as they help maintain soil fertility. Thisexplains why farmers plant legumes in soil before they plantnew crops.
Decomposers break down the protein in the bodies of plants,animals, and their wastes. In this process, ammonia is produced.Ammonia may be used directly by some plants but otherscannot. They have to transform this into nitrates through thenitrogen-fixing bacteria. This process converting ammonia tonitrates is known as nitrification. The plants are then able toobtain nitrates to synthesize amino acids and proteins.
The nitrates produced by the nitrogen-fixing bacteria areconverted into nitrites by another group of bacteria called nitritebacteria. Nitrites are converted into nitrogen by the denitrifying
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the bacteria in a process called denitration. Denitrationcompletes the cycle of nitrogen.
INSIGHTFULNESS
The most complex of the nutrient cycles is the nitrogencycle. It involves many microorganisms.
Nitrogen cannot be used directly by the plants. It has tobe transformed into nitrates.
Lightning, nitrogen-fixing bacteria, and decomposersconvert nitrogen into nitrates.
Denitrifying bacteria convert nitrites into nitrogen, thuscompleting the nitrogen cycle.
Plants use nitrogen for the synthesis of amino acids andproteins.
What will happen if the nitrates are not absorbed by plants? Isthis beneficial to the soil?
If nitrates are not absorbed by plants, they are washed awayby heavy rains. This process is called leaching. Leaching drainsthe soil of its nutrients which are ultimately lost into the riversand shallow marine sediments. These nitrates enter the marinefood chain and are returned to land by the droppings of seabirds.These droppings are known as guano, which is a major worldsupply of fertilizer.
GUIDE QUESTIONS
1. What is the important of nitrogen?
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2. What is the useful form of nitrogen?
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3. How is nitrogen converted into nitrates?
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4. What is nitrogen fixation?
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5. Differentiate between nitrification and denitrification.
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6. Explain leaching. What is its role in the nitrogen cycle?
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§5. THE PHOSPHORUS CYCLE
Phosphorus is essential to life. It is a component of the cellmembranes, nucleic acids, and adenosine triphosphate (ATP) –the energy currency of the cell.
Figure 2.4: The phosphorus cycle
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Phosphorus is found naturally in the environment in the formof phosphates. Phosphates in the soil come from phosphaterocks. Though the process of weathering, the phosphates areincorporated into the soil in soluble or insoluble forms. Theplants absorb the phosphate and use it for protein synthesis. Theanimals obtain phosphate from the plants they eat. When theplants and animals die, decomposition brings back the phosphateinto the soil.
Phosphate in the soil may be washed away into shallowmarine sediments by means of leaching. It may also reach thedeep ocean sediments. From the shallow marine sediments, thephosphates are returned to the soil in the form of guano depositsby marine fish and sediments. Phosphates in the deep oceansediments are recycled back to the soil by means of upwelling.If upwelling does not take place, the phosphate becomesincorporated into the phosphate rocks.
Phosphate rocks are mined to be used in the manufacture ofphosphate fertilizers. Though leaching, the phosphorus in thesefertilizers is lost from the soil. Human therefore hasten the rateof loss of available phosphate. This can have serious effects onthe supply of phosphorus for agriculture in the near future.
INSIGHTFULNESS
- Phosphorus presents in soil in the form of phosphates.Though weathering, phosphate rocks contribute to theamount of phosphate in the soil.
- Phosphate is taken in by plants and passed on the foodchain. When plants and animals die, the bacteria convert
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the dead bodies into phosphates and return them into thesoil.
- Guano deposits are good sources of phosphates.
Human activities have altered the cycle of materials in theenvironment. When people cut down trees or destroy forest in onearea, rainwater continues to flow until it finally reaches the seainstead of rising to the atmosphere and falling again on theforests. The massive destruction of the forests changes theenvironmental conditions, so that forests may never recover at all.
Figure 2.5: Eutrophication
Similarly, deforestation also affects the amount of nitrates inthe soil though leaching. This loss of nitrogen limits the growthof plants and pollutes groundwater.
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The phosphorus cycle has also been disrupted by theactivities of humans especially in the water ecosystem. Peopleuse a lot of agricultural fertilizers and detergents of whichphosphates are major components. When the phosphates fromfertilizers and detergents run off into lakes, they stimulate therapid growth of algae and other aquatic plants causing algaebloom. This condition is known as eutrophication.
As the plants age and die, decomposition takes place and useup so much oxygen causing the death of fish and other animals.
GUIDE QUESTIONS
1. What is the importance of phosphorus?
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2. What processes are involved in the cycle of phosphorus?
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3. In what ways have people altered the cycle of nutrients inthe environments?
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4. Define algae bloom. How does it lead to eutrophication?
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5. What are the effects of eutrophication?
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VOCABULARY
Algae bloom: Very rapid growth of algae in surface watersdue to increase in inorganic nutrients, especially phosphorusand nitrogen.
Conservation: Process of reducing the use of resourcesthrough recycling, decreased demand, and increased efficiencyuse.
Denitrifying bacteria: Bacteria that convert nitrates intonitrogen gas.
Denitrification: Process that convert nitrates into nitrogengas.
Eutrophication: Accumulation of nutrients in a lake or ponddue to human intervention or nature causes.
Evaporation: The process of the change in the state of aliquid or solid to a gas or vapor. Vanishing the surface of aliquid to the atmosphere.
Leaching: The process by which nutrient chemicals orcontaminants are dissolved and carried away by water, or aremoved into a lower layer of soil.
Nitrate: Inorganic anion containing three oxygen atoms andone nitrogen atom.
Nitrogen fixation: A process whereby nitrogen fixing bacterialiving in mutualistic associations with plants convertatmospheric nitrogen to nitrogen compounds that plants canutilize directly.
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Bacteria: Group of single - celled organisms responsible forfunctions like that decay of organic materials and nutrientrecycling.
Nutrient: Substance taken by a cell from its environment andused in catabolic or anabolic reactions.
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CHOOSE THE BEST ANSWER FOR THE FOLLOWINGQUESTIONS
1. The cause makes a pond or a lake with green surface is …..
a) polluted water
b) falling leaves
c) abundant in phytoplankton
d) the agrochemical
2. Adenosine triphosphate ………………..
a) is essential to life
b) has a lot of nutrients
c) is the energy currency of the cell
d) has a lot of nutrients and it is essential to life
3. Phosphorus is a component of ………………..
a) cell membranes
b) nucleic acids and adenosine triphosphate
c) cell membranes and adenosine triphosphate
d) cell membranes, nucleic acids and adenosine triphosphate
4. What do the plants use phosphate for?
a) supplying energy
b) protein synthesis
c) photosynthesis
d) protein synthesis and photosynthesis
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5. ……………….. brings back phosphate into the soil.
a) The excretion
b) The protein synthesis
c) The decomposition
d) The respiration
6. Phosphates in the soil may be washed away in to theshallow marine sediments by ………………..
a) means of leaching
b) decomposition
c) excretion
d) human and animals
7. Guano deposits are good sources of ………………..
a) nutrients
b) nitrates
c) nitrogens
d) phosphates
8. The cause of algae bloom is ………………..
a) the rapid growth of algae
b) the eutrophication
c) the increasing phosphorus and nitrogen
d) the rapid growth of aquatic plants
9. Nitrogen is an important component of ………………..
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a) nucleic acids
b) proteins
c) nucleic acids and proteins
d) nucleic acids and phosphorus
10. How many percent does the nitrogen gas constitute in theatmosphere?
a) About 58 percent.
b) About 68 percent.
c) About 78 percent.
d) About 88 percent.
11. How do plants and animals use nitrogen?
a) They use nitrogen directly.
b) They use nitrogen in its other form.
c) They can use it not only directly but also indirectly.
d) They don’t use nitrogen for their life.
12. Nitrogen in the atmosphere can be converted into nitratesby ………………..
a) the photosynthesis
b) the action of lightning
c) the action of specialized organisms
d) the action of lightning and specialized organisms
13. Which organism is the most important one in theconverting nitrogen?
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a) Bacteria
b) Algae
c) Fungi
d) Earth worm
14. The organism which converts nitrates into nitrites is …
a) rhizobium
b) algae
c) fungi
d) nitrite bacteria
15. What do plants use nitrogen for?
a) for the synthesis of amino acids
b) for the synthesis of proteins
c) for the synthesis of amino acids and proteins
d) for the photosynthesis
16. Carbon dioxide is present in the atmosphere form ……
a) wastes
b) dead bodies of organisms
c) fossil fuels
d) wastes, dead bodies of organisms and fossil fuels
17. Which process do plants use carbon dioxide in?
a) photosynthesis
b) respiration
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c) protein synthesis
d) amino acid synthesis
18. What is the saturation?
a) It is the process of releasing carbon dioxide.
b) It is the process of combining carbon dioxide with water.
c) It is the highest amount of moisture that the air can hold.
d) It is the process of releasing carbon dioxide andcombining carbon dioxide with water.
19. What is the difference between energy that flows into anecosystem and chemical nutrients?
a) Energy that flows into an ecosystem can be recycled andchemical nutrients are used repeatedly.
b) Energy that flows into an ecosystem cannot be recycledbut chemical nutrients are used repeatedly.
c) Energy that flows into an ecosystem cannot be recycledand chemical nutrients are not used repeatedly.
d) Energy that flows into an ecosystem is energy butchemical nutrients are materials.
20. The movement of the materials and nutrients between theliving and nonliving environment is known as …………
a) the energy flows
b) the energy cycles
c) the nutrients cycles
d) the nutrients flows
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21. The energy from the sun first flows to ………………..
a) the herbivore
b) the plants
c) the carnivore
d) omnivore
22. Choose the right sentence
a) The energy from the sun flows to the carnivore and tothe last consumer until the energy is lost into theecosystem.
b) The energy from the sun flows to the herbivore that eatsthe plant, goes to the carnivore, and to the last consumeruntil the energy is lost into the ecosystem.
c) The energy from the sun flows to the plants goes to theherbivore that eats the plant, to the carnivore, and to thelast consumer until the energy is lost into the ecosystem.
d) The energy from the sun flows to the animals goes to theherbivore that eats the plant, to the carnivore, and to thelast consumer until the energy is lost into the ecosystem.
23. The energy ………………..
a) cannot go back to the source
b) can be used over and over again
c) can go back to the source
d) can be stored in biomass only
24. Bacteria and fungi are known as ………………..
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a) consumers
b) decomposers
c) producers
d) consumers and decomposers
25. The nutrients ………………..
a) are stored in the abiotic environment
b) are stored in the biotic environment
c) are stored in the abiotic and the biotic environment
d) cannot stored at all
26. The nutrients can be used ………………..
a) over and over by plants
b) over and over by animals
c) over and over by decomposers
d) by producers, consumers and decomposers
27. Through the cycle of nutrients ………………..
a) the organic compounds found in the bodies of organismsaren’t converted into inorganic compounds
b) the organic compounds found in the bodies of organismsare converted into other organic compounds
c) the organic compounds found in the bodies of organismsare converted into inorganic compounds
d) the inorganic compounds found in the bodies oforganisms are converted into other inorganic compounds
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28. Nutrients may be classified into ………………..
a) one type
b) two types
c) three types
d) four types
29. What are the macronutrients?
a) They are carbon, hydrogen, oxygen and nitrogen.
b) They are copper and zinc.
c) They are iron and boron.
d) They are magnesium.
30. Choose the right sentence
a) Macronutrients are those that are required by theorganisms in large quantities.
b) Macronutrients are those that are required by theorganisms in small quantities.
c) Macronutrients aren’t the major components of fats andcarbohydrates.
d) Macronutrients are necessary in the production ofchlorophyll.
31. The highest amount of moisture that the air can hold iscalled ……………
a) evaporation
b) saturation
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c) respiration
d) condensation
32. The processes of ….. are responsible for the return ofwater from the atmosphere into the land and other bodiesof water.
a) evaporation and saturation
b) saturation and precipitation
c) condensation and precipitation
d) evaporation and precipitation
33. The water from the land and other bodies of waterreturns to the atmosphere through the process of ………
a) evaporation
b) saturation
c) condensation and precipitation
d) evaporation, saturation, condensation and precipitation
34. Returning of water from the atmosphere into the land andother bodies of water through ………………..
a) the process of evaporation
b) the processes of condensation and precipitation
c) the process of condensation
d) the process of precipitation
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35. Much of the carbon in the environment exists in the formof …..
a) coal, oil and gas
b) carbon dioxide
c) hydrogen carbonate (H2CO3)
d) calcium carbonate
36. Carbon dioxide mainly releases through ……..
a) the process of photosynthesis
b) the process of respiration
c) burning
d) the process of respiration and burning
37. Plants use CO2 in the process of ………………..
a) photosynthesis
b) respiration
c) burning
d) condensation
38. Though the process of respiration, animals ……………
a) obtain their food from the plants
b) release CO2
c) obtain there food from other animals
d) obtain their food from the plants and release CO2
39. Plants use nitrogen in the form of ………………..
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a) nitrites
b) nitrates
c) nitrites and nitrates
d) nitrogen
40. Nitrogen is ………………..
a) macronutrient
b) micronutrient
c) intermediate-nutrient
d) micronutrient and intermediate-nutrient
41. Nitrogen in the atmosphere is converted into nitrates in….. ways.
a) one way
b) two ways
c) three ways
d) many ways
42. The organisms that convert nitrogen are ………………..
a) bacteria
b) algae
c) fungi and algae
d) bacteria, algae, and fungi
43. The converting nitrites into nitrogen is called …………
a) nitrification
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b) denitrification
c) nitrogen-fixing
d) nitrogen cycle
44. The most complex of the nutrient cycles is ……………
a) carbon cycle
b) phosphorus cycle
c) water cycle
d) nitrogen cycle
45. The water from the land and other bodies of waterreturns to the atmosphere through ………………..
a) the process of evaporation
b) the processes of condensation and precipitation
c) the process of condensation
d) the process of precipitation
46. Algae bloom is ………………..
a) very rapid growth of algae in surface waters due toincrease in inorganic nutrients
b) very rapid growth of algae in surface waters due toincrease in organic nutrients
c) very rapid growth of algae in deep waters due to increasein inorganic nutrients
d) Very rapid growth of algae in deep waters due toincrease in organic nutrients
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47. Eutrophication is ………………..
a) Accumulation of nutrients in a lake or pond due tohuman intervention
b) Accumulation of nutrients in a lake or pond due tohuman intervention or nature causes
c) Accumulation of nutrients in a lake or pond due to naturecauses
d) Accumulation of organism in a lake or pond
48. Humans and animals produce carbon dioxide through …
a) the photosynthesis
b) protein synthesis
c) the process of respiration
d) decomposition
49. The process of manufacturing by green plants is called ….
a) protein synthesis
b) decomposition
c) the process of respiration
d) the photosynthesis
50. The energy currency of the cell is ………………..
a) adenosine triphosphate
b) cell membranes
c) nucleic acids
d) nutrients
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51. Plants use ……………….. for the protein synthesis.
a) carbon dioxide
b) water
c) phosphate
d) carbon dioxide and water
52. Plants use ……………….. for the synthesis of proteinsand amino acids.
a) phosphate
b) nitrogen
c) phosphate and nitrogen
d) carbon dioxide and water
53. Plants use……………….. for the photosynthesis.
a) water
b) carbon dioxide
c) sunlight
d) water, carbon dioxide and sunlight
54. The organic compounds are converted into the inorganiccompounds through …………
a) the cycle of nutrients
b) the cycle of water
c) the cycle of phosphorus
d) the cycle of carbon
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55. Carbon, hydrogen, oxygen and nitrogen are called ……
a) magnesium
b) macronutrients
c) magnesium and macronutrients
d) nutrients
56. The process of burning releases mainly ………………..
a) phosphorus
b) nitrogen
c) carbon dioxide
d) hydro carbonate
57. Nitrogen is the form that ………………..
a) plants can use
b) plants can’t use
c) the bacteria can’t convert
d) the fungi can’t convert
58. Denitrification is the process that ………………..
a) nitrogen convert into nitrites
b) nitrites convert into nitrates
c) nitrates convert into nitrites
d) nitrites convert into nitrogen
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59. The change in the physical, chemical or biologicalcondition in the environment which harmfully effects thequality of life, animals and plants is called ……………..
a) environmental pollution
b) deforestation
c) development
d) revolution
60. The energy that flows …... an ecosystem can’t berecycled.
a) in
b) into
c) over
d) through
61. When the bodies of dead plants and animals decompose,they are changed ………….. nutrients.
a) in
b) into
c) over
d) through
62. The nutrients are stored in the abiotic environment ……..the soil.
a) that
b) in
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c) like
d) of
63. The cycle of nutrients is an important process that takesplace …………… the ecosystem.
a) in
b) on
c) of
d) over
64. Nutrients may be classified into two types, namely, themacronutrients and …………..
a) The autotrophs
b) The nutrients
c) The biotic components
d) The micronutrients
65. ……………….. are the major components of fats andcarbonhydrates.
a) The nutrients
b) The macronutrients
c) The micronutrients
d) The macronutrients and micronutrients
66. ……………….. makes up many nucleic acids and is alsoessential for the transformation of energy in the cells.
a) Amino acid
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b) Protein
c) Nutrient
d) Phosphorus
67. Plants return the water by the process known as ………
a) transpiration
b) saturation
c) evaporation
d) respiration
68. Animals return the water by the process known as ……
a) transpiration
b) saturation
c) evaporation
d) respiration
69. Plants absorb carbon dioxide though the leaves and use……………….. the process of photosynthesis.
a) to
b) of
c) in
d) at
70. When the animals and plants die, their bodies and watersare broken down ……………….. the decomposers.
a) as
b) like
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c) in
d) by
71. When burned, fossil fuels release carbon dioxide………… the atmosphere.
a) in
b) into
c) on
d) at
72. Carbon dioxide combines ……………….. water andforms calcium carbonate.
a) with
b) by
c) to
d) and
73. Nitrogen-fixing bacteria are the Rhizobium, which livein the roots of legumes ………….. beans, peas, andpeanuts.
a) that
b) such as
c) by
d) and
74. This process converting ammonia to nitrates is known as …
a) nitrites cycle
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b) nitrogen cycle
c) denitration
d) nitrification
75. Phosphates in the soil come ……………phosphaterocks.
a) to
b) from
c) in
d) at
76. The phosphorus cycle has also been disrupted ……….the activities of humans especially in the waterecosystem.
a) by
b) to
c) caused
d) due to
77. Identify the error underlined word or phrase of thefollowing sentence: “The water from the land and otherbodies returns to the atmosphere through the processes ofevaporation”.
a) returns
b) through
c) processes
d) evaporation
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78. Identify the error underlined word or phrase of thefollowing sentence: “The nitrates produced by thenitrogen-fixing bacteria are converted into nitrites byanother group of bacteria call nitrite bacteria”.
a) produced
b) converted
c) by another group
d) call
79. Identify the error underlined word or phrase of thefollowing sentence: “When the phosphates fromfertilizers and detergents run off into lakes, theystimulate the rapid grow of algae and other aquatic plantscausing algae bloom”.
a) run off
b) stimulate
c) grow
d) causing
80. Identify the error underlined word or phrase of thefollowing sentence: “Plants absorb carbon dioxides andused them in the process of photosynthesis”.
a) absorb
b) carbon dioxides
c) used
d) in
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81. Identify the error underlined word or phrase of thefollowing sentence: “Leaching drain the soil of itsnutrients which are ultimately lost into the rivers andshallow marine sediments”.
a) drain
b) its
c) ultimately
d) into
82. Carbon exists in the earth’s atmosphere primarily as thegas ………………..
a) CO
b) CO2
c) H2CO3
d) CH4
83. Fungi and bacteria break down the carbon compounds indead animals and plants and convert the carbon to……… if oxygen is not present.
a) CH4
b) CO
c) CO2
d) H2CO3
84. Phosphorus normally occurs in nature as part of a ……ion.
a) PO43-
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b) HPO42-
c) H2PO4-
d) H3PO4
85. The main driving factor of the oxygen cycle is……………
a) nitrogen cycle
b) photosynthesis
c) evaporation
d) deforestation
86. Eutrophication means an increase in …………., typicallycompounds containing nitrogen or phosphorus, in anecosystem.
a) chemical toxicants
b) agrochemicals
c) chemical nutrients
d) chemical toxicants and nutrients
87. Eutrophication may occur ………………..
a) on land
b) in water
c) on land and in water
d) in the atmosphere
88. Nitrogen cycle is a ……………….. cycle.
a) gas
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b) gaseity
c) gasification
d) gaseous
89. Some nitrogen fixing bacteria, such as Rhizobium, livein ……….. of legumes such as peas or beans.
a) the root nodules
b) the root borers
c) the roof leaves
d) the root stocks
90. Some bacteria have the nitrogenase enzyme thatcombines gaseous nitrogen with hydrogen to produce …
a) NO
b) NO2
c) HNO3
d) NH3
91. During anaerobic conditions, ………… by bacteria occurs.
a) nitrification
b) denitrification
c) ammonification
d) nitrogen fixation
92. Following is the most widely discussed impact of climatechange:
a) increase in average sea level
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b) deforestation
c) soil erosion
d) deforestation and soil erosion
93. Climate change may have an impact on the following:……
a) agriculture, natural terrestrial ecosystems and waterresources
b) air quality, oceans and coastal zones
c) energy and human health
d) agriculture, natural terrestrial ecosystems, waterresources air quality, oceans and coastal zones, energyand human health
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CHAPTER 3: HUMANKIND’S INVENTION WITHNATURE
After studying this chapter, you should be able to
1. Discuss how ancient people affected the environment.
2. Explain the progress made in the field of agriculture.
3. Identify the advances in the area of medicine.
4. Enumerate the new technologies brought about byadvances in engineering.
5. Get a glimpse of the bad side of human beings impact onthe environment.
6. Enumerate some bad effects of modern technologies.
§1. BALANCE OF NATURE
Scientists estimated that the earth is already around threebillion years old, and it will exists for another three billion years.The life of the earth depends mainly on the sun. If thegravitational pull of the sun remains constant, the earth willcontinue to revolve around the sun in its present speed. There isa delicate balance between the centrifugal force of the earth as isgoes around the sun.
If the sun continues to shine as the way it is now, then the earthwill continue to receive radiant energy needed by the livingcreatures. Again, there is a delicate balance here. Too muchsunshine will make the earth too hot for most living beings tosurvive. In short, the balance of nature is so delicate that any actionthat might upset such balance could have catastrophic results.
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For millions of years, this balance of nature has beenmaintained. The animals that antedated humans for thousands ofyear did not really disturb the environment. The effect theymade on the environment was minimal and Mother Natureeasily recovered.
During the dawn of civilization, humans and the predatorslived in very similar ways. Both hunted for food and dwelt innatural habitats, like caves. With this kind of life, they did notalter the environment. But, since humans were more intelligentand more cunning, plus the fact that they walked erect and madeuse of their hands, they were able to invent weapons to helpthem. Axe from stones and spears from sharp object made thembetter hunters than the animals. And when they learned the useof fire, they cooked their food with it, warmed their bodies by it,and heated a lot of things to help them survive. That was whenhumans proved their superiority over animals.
When they learned to eat green leafy vegetables and learnedhow to cultivate them, they started to alter the environment. Theymade clearings in the forests and planted vegetables. When theland was no longer that fertile, they abandoned the place andcleared other lands. That was the beginning of forest destruction.Then they learned how to domesticate animals and lived in apermanent dwelling which was made of (from) the products ofthe environment, like wood for the structure and leaves forroofing. They had to change the environment some more.Fortunately, there were not so many people at that time, so theenvironment was able to recover. The balance of nature remained.
As the population increased and the needs of people becamemore complex, they put greater and greater pressure on the
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environment. Larger houses were constructed from differentmaterials, strong fences to protect them from enemies, irrigationcanals for agriculture, and large enclosures for animals, all theserequired more change in the environment. But even then, therewas no serious damage to the environment from which nature wasunable to recover. It could be said then that by and large, humanslives for many, many years in harmony with the environment.
The rise in civilization of the Sumerians, the Babylonians, theEgyptians, the Greeks, and the Romans placed additional burdenon Mother Earth, especially in the terms of land used for publicbuildings, monuments, and, of course, houses. With more landsused for agriculture and the upkeep of animals, especially thoseused in war, changes in the environment became morepermanent. But even then, they were not causes for worry.
It was only during the rapid progress in knowledge about theworld, followed by the so-called industrial revolution, whenhumans made greater impact on the environment.
GUIDE QUESTIONS
1. Explain in details the meaning of balance of nature
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
2. Name some ways by which humans upset the balance ofnature.
……………………………………………………………………………
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……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
§2. PROGRESS IN AGRICULTURE, ENGINEERING,AND MEDICINE
Because of their superior intelligence, aided by the virtues ofcuriosity, imagination, and creativity, humans were able to discoverthe many laws of nature, and they used this knowledge to controlparts of nature mostly for the benefit of humankind, in general.
In the field of agriculture, the knowledge of geneticsproduced larger and better varieties of fruits and vegetables.These varieties gave better yields per area planted and weremore resistant to diseases. Some examples will be enumerated tohighlight the point.
Better yielding varieties of rice, wheat, and potatoes haveresulted in bumper harvest in many parts of the world. As thedirect consequence, the problem of feeding the growingpopulations was partly solved by these discoveries.
Scientists were able to breed seedless grapes and seedlesspapayas. Mangoes are now harvested all year round. Andperhaps, the other fruits may soon be grown seedless, likemelons, and watermelons. Large varieties of guavas and Santoare now in abundance.
In the field of medicine, doctor and the scientists were able todiscover the cure for many diseases, thus prolonging and
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preserving producing healthier babies. The end result of all theseare a much faster rate of population increase.
In the field of animal science, researchers were able toimprove the breed of animals used for food. Faster-growingchickens and pigs and cultured fish are some good examples.Artificial hatching of eggs was invented. All these resulted inmore food for the fast-growing population of the world.
In the field of engineering, scientists invented better means oftransportation on land, at sea, and in the air. The more recentinventions include the bullet train that can run up to 500kilometers (km) per hour, airplanes that can carry up to 700passengers, and large ships powered by nuclear fuels.
Landscapes have been altered to improve services to thepeople. For instance, dams were built to produce electricity forhomes and factories. Oil, coal, and other fossil fuels were minedto power these new inventions.
For more comfort at home, scientists invented artificiallighting, air-conditioning systems, refrigerator to preserve foodbetter, radio and television for faster and better dissemination ofinformation and for entertainment, and all those electric gadgetsin the kitchen to the delight of many housewives.
In the field of food technology, we can choose from a verywide variety of food available in the market, canned goods of allkinds, powered milk, packed lunches, preserved fruits andvegetables, and many others.
All there may be considered as the good impact humans havemade on the environment. As a result of these inventions andnew technology, people are living better food, live in more
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comfortable homes, enjoy their vacations more, get better healthservices, travel faster, and dress better. In short, they can do a lotbetter than their ancestors.
§3. ADVERSE EFFECTS OF PEOPLE’S ACTIVITIES
Humankind’s intervention with nature has its adverse effectstoo. These include the pollution produced by modern technologyand its ill effects on the environment (disruption of theatmosphere which causes greenhouse effect, ozone depletionand acid rain); among others; pollution of the water system,deforestation, improper disposal of solid wastes, as well asnuclear wastes; and noise pollution.
1. The greenhouse effect
The greenhouse effect is the rise in temperature that the Earthexperiences because certain gases in the atmosphere (watervapor, carbon dioxide, nitrous oxide, and methane, for example)trap energy from the sun. Without these gases, heat wouldescape back into space and Earth’s average temperature wouldbe about 60ºF colder. Because of how they warm our world,these gases are referred to as greenhouse gases.
The greenhouse effect is important. Without the greenhouseeffect, the Earth would not be warm enough for humans to live.But if the greenhouse effect becomes stronger, it could make theEarth warmer than usual. Even a little extra warming may causeproblems for humans, plants, and animals.
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Figure 3.1: The greenhouse effect
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Too much carbon dioxide and other gases emitted byfactories are accumulating in the atmosphere. These gases allowsunlight to penetrate the earth’s atmosphere but unfortunately,they also trap radiant heat and revert its escape into outer space.
The immediate consequence is global warming, which isbetter known as the green-house effect. The rise in the averagetemperature of the earth could have serious consequences.Among them is the melting of ice and glaciers in the North andSouth poles. This will raise the water level in many areas of theworld, resulting in the submersion of the low-lying coastaltowns and cities.
2. Ozone depletion
High above the earth’s atmosphere, between 15 and 59 kmabove the earth, is a layer of ozone (O3). It is formed whenultraviolet radiation (UV) splits a molecule of oxygen (O2), andthe free oxygen atoms (O) combines with other oxygenmolecules. When found on the surface of the planet, ozone isconsidered a dangerous pollutant and is one substanceresponsible for producing the greenhouse effect.
Ozone acts as a filter in the upper atmosphere, preventing theharmful ultraviolet radiation of the sun from reaching the earth.Scientists discovered that compounds of carbon such as carbondioxide (CO2) and chlorofluorocarbons (CFCs), nitrogen oxides(NO) and methane break up ozone molecules, thereby graduallydepleting it.
The fact that the ozone layer was being depleted wasdiscovered in the mid-1980s. The main cause of this is therelease of CFCs, chlorofluorocarbons.
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Figure 3.2: Ozone depletion
Large ozone hole was discovered above the tip of SouthAmerica. The people directly below it may experience skinirritations and soreness in their eyes. This may be due to thehigher intensity of harmful ultraviolet radiations hitting them.
Ozone levels, on the average, have declined by around 2percent between 1969 and 1988. But in some parts of the world,the decrease in much higher. For example, in Melbourne ofAustralia, ozone levels dropped by as much as 10 percent in1987, causing a 20 percent increase in ultraviolet radiationreaching the ground.
Antarctica (Nam cực) was an early victim of ozonedestruction. A massive hole in the ozone layer right above theAntarctica now threatens not only that continent, but manyothers that could be the victims of Antarctica's melting icecaps.In the future, the ozone problem will have to be solved so thatthe protective ozone layer.
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3. Acid rain
The term acid rain refers to what scientists call aciddeposition.
Sulfur and nitrogen oxides are released from industrialfactories, electrical power plants, smelting plants, and motorvehicles. When these gases combine with the moisture in theatmosphere, they return to the ground as sulfuric acids and nitricacids. These are popularly known as acids rain.
Figure 3.3: Acid rain
Acid rain, one of the most important environmental problems ofall, cannot be seen. Acid rain is having harmful effects both onpeople and on the natural ecosystems of the world. Scientists todayare convinced that acid rain is severe in many areas, and that it ishaving an adverse effect on the environments of those locations.
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The problem of acid rain is rapidly spreading. Because it ismainly caused by industrial processes, automobiles, and powerplants, those countries that are developed have the most severeacid rain problems. However, as the undeveloped nations beginto industrialize, acid rain will increase greatly.
Determining just how much the planet is being hurt by acidrain is very difficult because the ecosystems that it affects are sodiverse and complex.
Many ecosystems are affected by acid rain. Bodies of water,such as lakes and rivers, see many of their inhabitants die offdue to rising acidity levels.
Acidic water also ruins (làm hỏng) plant nutrients, hurtingplants' ability to survive and to give negative effects to otherorganisms.
Human-made products are also experiencing degradationfrom acid rain. Cars can lose their finishes, and outdoor statuesare beginning to rust (gỉ).
Acid rain's effects are destructive and long lasting. Thoughscientists have studied lakes, streams, and many other naturalecosystems to prove its negative effects, acid rain continues tobe produced and is increasing in many parts of the world.
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Acid rain and limestone Trees affected by acid rain
Figure 3.4: Effects of acid rain
Many lakes in the Scandinavian countries are seriouslyaffected by acid rain. Acid rain has brought extensive damage tothe trees of Europe and the Eastern part of the United States.Famous buildings like the Taj Mahal in India are now beingdamaged by acids from local oil refineries.
4. Water pollution
Industrial wastes disposed of in streams and rivers havepolluted these bodies of water, making them unfit for fish andother aquatic animals to inhabit. When the water from thesestreams and rivers flows into lakes and oceans, then these bodiesof water also become polluted. Wastes from industrial factoriesalong the riverbanks polluted the river so much that for allpractical purposes, the river is dead.
Most of the industrial factories that dump their wastes intoaround rivers make water pollution. The immediate consequenceis the large reduction in fish catch.
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Attention for water pollution exploded in the 1980s. The oilspill of the Exxon Valdez showed many around the world justhow horrible the effects of water pollution could be.
Drainage water pollution Solid wastes disposed to water
Severe water pollution Oil pollution
Figure 3.5: Water pollution
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There are many rivers and lakes in our country are sufferingfrom pollution, perhaps to a lesser extent but nevertheless aserious threat to the environment. If you add the bodies of waterin other countries that are also polluted, then you will feel howserious this threat is to the earth’s environment.
The effects of water pollution are varied and depend on whatchemicals are dumped and in what locations.
Boston Harbor is a strong example of how badly pollutioncan damage bodies of water. The water is filled with toxic wasteand sewage, and routinely receives more waste when rainfallpushes it into the harbor.
Many bodies of water near urban areas are highly polluted.This is the result of both garbage dumped by individuals anddangerous chemicals legally or illegally dumped by industries.
The main problem caused by water pollution is that it killslife that inhabits water-based ecosystems. Dead fish, birds,dolphins, and many other animals often wind up on beaches,killed by pollutants in their habitat.
Pollution disrupts the natural food chain as well. Pollutantssuch as lead and cadmium are eaten by tiny animals. Later, theseanimals are consumed by fish and shellfish, and the food chaincontinues to be disrupted at all higher levels.
Eventually, humans are affected by this process as well. People canget diseases such as hepatitis by eating seafood that has been poisoned.
Ecosystems can be severely changed or destroyed by waterpollution. Many areas are now being affected by careless humanpollution, and this pollution is coming back to hurt humans.
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5. Deforestation
Forests cover around a quarter to a third of the total land surfaceof the earth. The reduction in area of this valuable environmental,social and economic resource through deforestation has the potentialto cause problems on a global scale. Climate models havedemonstrated a clear link between deforestation and climate change.
Deforestation occurs at an alarming rate. Twenty-three percentof the earth's land surface is covered by tropical rainforest;however, these forests disappear at a rate of 4.6 million hectares ayear. Forests are an integral part for the well-being of life onearth.
Figure 3.6: Deforestation
Many environmental problems such as flooding of rivers, theloss of biodiversity, accelerated soil erosion, resulting in the lossof the fertility of the land; flooding during heavy rains because
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there are no more trees to hold and store the water; silting ofrivers and lakes with soil and rocks carried by the floods; loss ofhabitat to many animal and plant species. Resulting in theirextinction; and deforested areas becoming barren and useless.
6. Solid waste disposal
Progress produces a large amount of garbage. Much of theseare nonbiodegradable (do not decay into useful fertilizer) orhazardous materials.
Figure 3.7: Solid waste disposal
How to dispose of them is a big problem in many countries.The most popular way is landfills. In Vietnam, garbage collectionis not efficient. With an indifferent population, garbage is one ofthe main sources of pollution especially in large populationcenters like Ho Chi Minh City. When garbage is not collected ontime, people tend to dump them almost everywhere, resulting invery unsanitary surroundings, clogged waterways, and pollutedcreeks and rivers. Improper garbage disposal is known to havetriggered the spread of diseases, epidemics, and other adverseeffects on people’s health.
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7. Nuclear waste
Nuclear power is among the most efficient and relativelycheap sources of energy. But the technology is highlysophisticated and the possibility of nuclear disaster is notremoted.
Figure 3.8: Nuclear waste
The resulting nuclear radiations are very harmful to humanbeings and heavy dozes are fatal. The thousands of deaths due tothe atomic bombings of Hiroshima and Nagasaki during theSecond World war and the hundreds of fatalities in the
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Chernobyl accident in the former Soviet Union are grimreminders of what could happen in the case of nuclear accidents.
Figure 3.9: Hiroshima and Nagasaki disasters
Figure 3.10: The bombing of Hiroshima and Nagasaki
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8. Noise pollution
Figure 3.11: Noise pollution from speaking-trumpet
Figure 3.12: Air and noise pollution
Noise pollution is a direct result of industrial revolution.Noisy engines in factories, the noise produced by motorvehicles, the irritating noise produced by the jackhammer, and
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the most unbearable noise from jet engines are some example.Perhaps noise pollution is the least paid attention to but the illeffects it has one people are well documented. Psychologicaleffects including irritability, mental stress, and shorttemperedness are quite common. Temporary or permanent lossof hearing is a more serious physical effect of noise pollution.
The impact of the different kinds of pollution on the peopleand environment is serious. Permanent and irreparable damageson the ecosystem could make the earth no longer a pleasantplace to live in and could even make it uninhabitable. That iswhy pollution and its effects on the environment should be theconcern of everybody.
GUIDE QUESTIONS
1. Which of the types of pollution briefly described above isthe most dangerous?
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
2. As a student, how can you help in the proper disposal ofgarbage?
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
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3. Do you know of steps taken by the government and/orother agencies to protect the environment from harmfulpollution?
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
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VOCABULARY
Acid precipitation: Rain or snow that has lower pH thanprecipitation from unpolluted skies.
Acid rain: Moisture in the atmosphere which has beencontaminated by oxides of sulfur and nitrogen.
Deforestation: Destruction of forest
Greenhouse effect: Rising of the average global temperaturecaused by the accumulation of the carbon dioxide and othergases in the atmosphere. These gases trap radiant heat andprevent its escape into space.
Nuclear fission: Splitting of an atomic nucleus when struck byneutrons.
Nuclear fusion: Joining of two small atomic nuclei to form anew and large nucleus.
Nuclear power: Energy derived from nuclear fission orfusion.
Ozone: Molecule that contains three molecules of oxygenfound in the atmosphere and which screens ultraviolet rays.
Ozone layer (or the ozonosphere): Thin layer of ozone in theupper atmosphere which absorbs ultraviolet light and convertsit into infrared radiation.
Pollution: That which occurs when there is a change in thephysical, chemical, or biological conditions in the environmentwhich harmfully effects the quality of life, including effects onother animals and plants.
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CHOOSE THE BEST ANSWER FOR THE FOLLOWINGQUESTIONS
1. Rising of the average global temperature due to theaccumulation of the carbon dioxide and other gases in theatmosphere causes of ………………..
a) acid rain
b) greenhouse effect
c) air pollution
d) ozone depletion
2. Greenhouse effect is known as ………………..
a) The global warming
b) The red tie
c) The cool weather
d) The normal weather phenomenon
3. One of the consequences of greenhouse effect is …………
a) the lowering sea level
b) the appearance of many low-lying coastal cities
c) the melting of ice and glaciers in the Poles
d) the arising epidemic diseases
4. The consequence of raising sea level in many places of theworld is ………………..
a) the submersion of the low-lying coastal towns and cities
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b) the melting of ice and glaciers in the North and Southpoles
c) the global warming
d) the water pollution
5. How high does the ozone layer distribute above the earth?
a) 15 – 29 km
b) 15 – 39 km
c) 15 – 49 km
d) 15 – 59 km
6. The layer that distributes between 15 and 59 km above theearth is ………………..
a) the ionosphere
b) the stratosphere
c) the ozone layer
d) the troposphere
7. The free oxygen atoms combines with the other oxygenmolecules will form ……………
a) the ozone
b) the acid
c) the ultraviolet radiation
d) the base
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8. The functions of ozone layer are ………………..
a) filtering in the upper atmosphere and destroying theatmosphere
b) preventing the harmful UV of the sun from reach theearth and destroying the atmosphere
c) filtering in the upper atmosphere and preventing theharmful UV of the sun from reach the earth
d) filtering in the upper atmosphere, preventing the harmful UVof the sun from reach the earth and destroying the atmosphere
9. CFCs can ………………..
a) deplete the ozone layer
b) break up ozone molecules
c) make air polluted
d) deplete the ozone layer, break up ozone molecules andmake air polluted
10. Which compounds can deplete the ozone layer?
a) Carbon dioxide, chlorofluorocarbons, nitrogen oxide andmethane
b) Chlorofluorocarbons, carbon dioxide and methane
c) Chlorofluorocarbons, carbon dioxide and nitrogen oxide
d) Chlorofluorocarbons, carbon dioxide
11. The moisture in the atmosphere which has been contaminatedby oxides of sulfur and nitrogen is called ……
a) greenhouse effect
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b) air pollution
c) acid rain
d) ozone depletion
12. The mainly components of acid rain are ………………..
a) nitric acid and nucleic acid
b) nitric acid and amino acid
c) sulfuric acid and nitric acid
d) sulfuric acid and amino acid
13. Acid rain ………….. to the lakes, soil, forest and buildings.
a) do a great deal of harm
b) does a great deal of harm
c) do a great deal of harm
d) does a great deal of harm
14. The specific chemical properties of acid rain are …………
a) heatproof and degradation
b) erodent and degradation
c) heatproof and erodent
d) degradation, heatproof and erodent
15. Non-bio-degradable waste means ………………..
a) the waste that can’t decay into the useful fertilizer
b) the waste that can decay into the useful fertilizer
c) the waste that can’t be reused
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d) the waste that can be reused.
16. The most efficient way to dispose waste is ………………..
a) recycling
b) incineration
c) energy recovery
d) landfilling
17. Deforestation is ………………..
a) the prevention of forest
b) the destruction of forest
c) the planting
d) the delivery of forest
18. Most of the industrial factories that dump their wastes intoaround rivers makes …………
a) air pollution
b) soil pollution
c) water pollution
d) air, soil and water pollution
19. How many percent did the tropical rainforest cover theearth’s land surface?
a) About 20 – 25 percent
b) About 25 – 30 percent
c) About 30 – 35 percent
d) About 35 – 40 percent
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20. Lost of forest can cause ………………..
a) flooding of rivers
b) loss of bio-diversity
c) soil degradation
d) flooding of rivers, loss of bio-diversity and soildegradation
21. Nuclear power is not used widely because ………………..
a) the nuclear power production need a high andsophisticated technology
b) the nuclear power is not safe
c) the possibility of nuclear disaster is not remote
d) the nuclear power is not safe, its production need a hightechnology and the possibility of nuclear disaster is not remote
22. Forest trees can hold and store the water, therefore ………
a) many regions have been deforested for firewood.
b) fooding during heavy rains can be minimized.
c) deforestation occurs at an alarming rate
d) forests are an integral part for the well-being of life onearth.
23. What are the non-biodegradable wastes?
a) They are the industrial wastes
b) They are the municipal solid waste
c) They can’t be decayed into useful fertilizer
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d) They are the hazardous wastes.
24. Nuclear power is one of the most ………………..
a) expensive sources of energy
b) inefficient sources of energy
c) expensive and inefficient sources of energy
d) cheap and efficient sources of energy
25. Noise pollution is a direct result of ………………..
a) industrial revolution
b) agricultural revolution
c) industrial and agricultural revolution
d) natural phenomenon
26. Noise pollution is the cause of ………………..
a) temporary or permanent loss of hearing
b) irritability
c) stress
d) temporary or permanent loss of hearing, irritability andstress
27. Nuclear fission is ………………..
a) the combination of two small atomic nucleic to form anew and large nucleus.
b) the splitting of an atomic nucleus.
c) energy derived from nuclear
d) energy derived from nuclear fusion
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28. Nuclear fusion is ………………..
a) the combination of two small atomic nucleic to form anew and large nucleus.
b) the splitting of an atomic nucleus.
c) energy derived from nuclear
d) energy derived from nuclear fusion
29. Rain or snow that has lower pH than precipitation fromunpolluted skies is called ………………..
a) pollution
b) hail
c) acid precipitation
d) acid
30. Scientists estimated that the earth is already around ………
a) three billion years old, and it will exists for another threebillion years
b) two billion years old, and it will exists for another twobillion years
c) one billion years old, and it will exists for another onebillion years
d) four billion years old, and it will exists for another fourbillion years
31. The life of the earth depends mainly on ………………..
a) the earth
b) the air
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c) the sun
d) the water
32. Too much sunshine will ………………..
a) make the earth too cold for most living beings to survive
b) create balance of nature
c) make the earth too hot for most living beings to survive
d) upset the balance of nature
33. During the dawn of civilization ………………..
a) humans and the predator animals lived in very similarways
b) humans and the predator animals lived in very differentways
c) humans and the autotrophs lived in very similar ways
d) humans and the autotrophs lived in very different ways
34. During the dawn of civilization, both humans and animals …
a) hunted for foods
b) dwelt in natural habitats
c) hunted for foods and dwelt in natural habitats
d) alter the environment
35. Humans proved their superiority over animals by ………
a) more intelligent and more cunning
b) learning the use of fire
c) making use of their hands
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d) more intelligent, learning the use of fire and making useof their hands
36. Yielding varieties of …………….. have resulted in bumperharvest in many parts of the world.
a) potatoes
b) wheat
c) rice
d) rice, wheat, and potatoes
37. Humans started to alter the environment ………………..
a) during the dawn of civilization
b) when they learned to eat green leafy vegetables andlearned how to cultivate them
c) when they ate green leafy vegetables
d) as the population increased and the needs of peoplebecame more complex
38. Faster rate of population increase depends on ……………
a) medicine improvement
b) agriculture improvement
c) food engineering improvement
d) medicine, agriculture and food engineering improvement
39. The disruption of the atmosphere will causes ……………
a) greenhouse effect
b) ozone depletion
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c) acid rain
d) greenhouse effect, ozone depletion and acid rain
40. The pollution produced by modern technology depends on …
a) improper disposal of solid wastes, nuclear wastes andnoise pollution
b) nuclear wastes
c) improper disposal of solid wastes
d) noise pollution
41. Green-house effect is the result of ………………..
a) carbon dioxide emitted by factories in the atmosphere
b) gases emitted by factories in the atmosphere
c) too much carbon dioxide and other gases emitted byfactories in the atmosphere
d) noise pollution
42. The consequence of global warming is known as …………
a) greenhouse effect
b) ozone depletion
c) acid rain
d) greenhouse effect, acid rain and ozone depletion
43. Rising in the average temperature of the earth is impactedby ………………..
a) too much carbon dioxide accumulates in the atmosphere
b) too much methane accumulates in the atmosphere
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c) too much other gases accumulates in the atmosphere
d) too much carbon dioxide, methane and other gasesaccumulate in the atmosphere
44. Greenhouse gases can ………………..
a) allow sunlight to penetrate the earth’s atmosphere
b) trap radiant heat
c) allow sunlight to penetrate the earth’s atmosphere, trapradiant heat and revert its escape into outer space
d) revert radiant heat’s escape into outer space
45. Greenhouse effect can ………………..
a) melt ice and glaciers
b) raise the water level in many part of the world
c) submerse the low-lying coastal towns and cities
d) melt ice and glaciers, raise the water level in many partof the world and submerse the low-lying coastal townsand cities
46. Ozone acts as a filter in the upper atmosphere because …...
a) it prevents the harmful ultraviolet radiation of the sunfrom reaching the earth
b) it is formed when UV splits a molecule of oxygen, andthe free oxygen atoms combine with other oxygenmolecules
c) it distributes high above the earth’s atmosphere
d) it distributes between 15 and 59 km above the earth
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47. Ozone depletion will ………………..
a) raise the water level in many part of the world
b) revert radiant heat’s escape into outer space
c) increase in ultraviolet radiation reaching the ground
d) decrease in ultraviolet radiation reaching the ground
48. Acid rain dues to ………………..
a) sulfur oxides are released from industrial factories
b) nitrogen oxides are released from industrial factories
c) motor vehicles
d) sulfur and nitrogen oxides are released from industrialfactories, electrical power plants, smelting plants, andmotor vehicles
49. Famous buildings are now being damaged by ……………
a) ozone depletion
b) greenhouse effect
c) acid rain
d) ozone depletion, acid rain and greenhouse effect
50. Water pollution dues to ………………..
a) industrial solid wastes
b) industrial water waste
c) domestic wastes
d) industrial and domestic wastes
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51. Water pollution will result in ………………..
a) oxygen exhaust
b) reduction in fish catch
c) unfit for all practical purposes
d) oxygen exhaust, reduction in fish catch and unfit for allpractical purposes
52. Many environmental problems such as ……………….. arecaused by deforestation
a) flooding
b) the loss of biodiversity
c) accelerated soil erosion
d) flooding, the loss of biodiversity, accelerated soilerosion, etc
53. Which type of pollution described below is the mostdanger?
a) Greenhouse effect
b) Water pollution
c) Nuclear waste
d) Solid waste
54. Thousands of deaths due to the atomic bombings ofHiroshima and Nagasaki during the second World war andthe hundreds of fatalities in the Chernobyl accident in theformer Soviet Union are cases of ………………..
a) photochemistry
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b) greenhouse effect
c) nuclear accidents
d) acid rain
55. Acid rain is caused by ………………..
a) contaminating of oxides of sulfur and nitrogen inatmosphere
b) water pollution
c) higher pH than the precipitation from unpolluted skies
d) deforestation
56. Greenhouse effect makes ………………..
a) rise of the average global temperature
b) accumulation of the carbon dioxide
c) rise in other gases in the atmosphere
d) rise of the average global temperature cause by theaccumulation of the carbon dioxide and other gases inthe atmosphere
57. Nuclear power is ………………..
a) the energy derived from nuclear fission or fusion
b) the energy derived from nuclear fission
c) the energy derived from nuclear fusion
d) the energy derived from nuclear
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58. Pollution occurs when ………………..
a) there is a change in the physical conditions in theenvironment
b) there is a change in the chemical conditions in theenvironment
c) there is a change in the biological conditions in theenvironment
d) there is a change in the physical, chemical or biologicalconditions in the environment
59. As the population increased, humans put greater andgreater pressure ……………….. the environment.
a) in
b) on
c) at
d) off
60. The rise in the average temperature of the earth could haveserious ………………..
a) consequences
b) results
c) advantage
d) disadvantage
61. Greenhouse effect will raise the water level ……… manyareas of the world.
a) at
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b) on
c) in
d) of
62. Carbon dioxide, chlorofluorocarbons, nitrogen oxides andmethane can ……………….. ozone layer.
a) break down
b) push off
c) destroy
d) deplete
63. Acid rain brings damage …… lakes, the soil, forest and buildings.
a) to
b) in
c) up
d) on
64. Most of the industrial factories ……….. dump their wastesinto around rivers make water pollution.
a) who
b) whom
c) that
d) such as
65. Deforestation occurs ……………….. an alarming rate.
a) at
b) on
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c) in
d) of
66. Human’s activities produce a large amount …… garbage.
a) at
b) on
c) in
d) of
67. The nuclear radiations ……very harmful to human beings.
a) is
b) are
c) was
d) were
68. Noise pollution is a direct result of …………revolution.
a) industry
b) industrial
c) industrialize
d) industrially
69. Deforested areas are becoming barren …… useless.
a) but
b) or
c) and
d) of
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70. Nuclear power is one of efficient and cheap sources …… energy.
a) at
b) on
c) in
d) of
71. Who discovered the greenhouse effect?
a) Joseph Fourier
b) Elihu Thomas
c) Wilhelm Conrad Roentgen
d) Thomas Alva Edition
72. When was greenhouse effect discovered?
a) 1624
b) 1724
c) 1824
d) 1924
73. Acid rain is mostly caused by………………..
a) human emissions of sulfur compounds
b) human emissions of nitrogen compounds
c) human emissions of sulfur and nitrogen compounds
d) human emissions of water and vapour water
74. Acid rain was first found in ………………..
a) United States
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b) Sweden
c) Vietnam
d) Singapore
75. The process in which the emission of infrared radiation bythe atmosphere warms a planet’s surface is called ………
a) photosynthesis
b) greenhouse effect
c) acid rain
d) ozone depletion
76. Which country is the leading country that undertakesrecycling?
a) United States
b) Germany
c) England
d) Japan
77. How many percent can Japan can recycle or reuse theirsolid wastes?
a) about 11%
b) about 15%
c) about 27%
d) about 50%
78. A site for the disposal of waste material by burial is called ………
a) storehouse
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b) graveyard
c) landfill
d) a) and b) are correct
79. The oldest form of waste treatment is ………………..
a) landfilling
b) incinerating
c) composting
d) recycling
80. …………… has the greatest role in the greenhouse effect.
a) CO2
b) CFC
c) CH4
d) NO2
81. ……………….. has the least role in the greenhouse effect.
a) CO2
b) CFC
c) CH4
d) NO2
82. Identify the error underlined word or phrase of thefollowing sentence: “Sulfur and nitrogen oxide are releasedfrom industry factories, electrical power plants, smeltingplants and motor vehicles”.
a) are released
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b) industry
c) electrical
d) smelting
83. Identify the error underlined word or phrase of thefollowing sentence: “When humans learned to eatvegetables and learned how to cultivate them, they startedto altered the environment”.
a) humans
b) eat
c) how to
d) altered
84. Identify the error underlined word or phrase of thefollowing sentence: “In the field of agricultural, theknowledge of genetics produced larger and better varietiesof fruits and vegetables”.
a) in
b) agricultural
c) genetics
d) larger and better
85. Identify the error underlined word or phrase of thefollowing sentence: “This will raise the water level inmany area of the world, resulting in the submersion of thelow-lying coastal towns and cities”.
a) water level
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b) area
c) resulting
d) low-lying
86. Identify the error underlined word or phrase of thefollowing sentence: “Ozone acts as a filters in the upperatmosphere, preventing the harmful ultraviolet radiation ofthe sun from reaching the earth”.
a) filters
b) preventing
c) harmful
d) from
87. Identify the error underlined word or phrase of thefollowing sentence: “Improper garbage disposal is knownto have triggered the spread of diseases, epidemics andother adverse effects at people’s health”.
a) disposal
b) known
c) spread of
d) at
88. The destruction of significant areas of forest cover hasresulted in a degraded environment with reduced …………
a) pollution
b) population
c) biodiversity
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d) animals
89. Deforestation results from removal of trees without sufficient ……
a) reforestation
b) forest
c) forester
d) forestation
90. Deforestation affects the amount of water in the soil andgroundwater and the moisture in the atmosphere.
a) amount of water in soil
b) amount of water in groundwater
c) the moisture in the atmosphere
d) the moisture in the atmosphere and amount of water insoil and in groundwater
91. Garbage generated in households can be ……… to preventcreation of waste at source and reducing amount of waste.
a) recycled
b) reused
c) recycled and reused
d) thrown away
92. Household waste is generally classified as ………………..
a) hazardous waste
b) municipal waste
c) biomedical waste
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d) solid waste
93. There are various municipal waste disposal methods. Oneof the following methods solves the problem of leaching tosome extent.
a) open dumps
b) landfills
c) sanitary landfills
d) open dumps, landfills and sanitary landfills
94. Which is potentially the safest means of disposing of the mosttoxic wastes: organic solvents, chlorinated hydrocarbons, PCBsand dioxins?
a) municipal incineration
b) industrial high temperature incineration
c) landfills
d) municipal incineration and landfills
95. Municipal waste is disposed in the open dumps, landfills,sanitary landfills, and is also burnt in large furnaces. Thismethod is known as ………………..
a) incineration
b) blast furnace
c) waste furnace
d) incineration, blast furnace and waste furnace
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CHAPTER 4: THE POLLUTION PROBLEMS
After studying this chapter, you will be able to:
1. Trace the history of pollution in the world.
2. Identify the major sources of worldwide pollution.
3. Distinguish between toxic pollutants and those that areharmful only to the environment.
4. Describe the main causes of air, water, and landpollution.
5. Enumerate the efforts exerted by some people to helpreduce pollution.
§1. MEANING OF POLLUTION
When there is a change in the physical, chemical, orbiological conditions in the environment which harmfullyaffects the quality of life, including effects on other animals andplants, then we say that there is pollution in the environment.
The change is generally brought about by introduction ofhazardous substance into the environment. A hazardous substanceincludes any substance that poses a threat to human health or to theenvironment. Substances that are poisonous to human beings andanimals are called toxicants. Those that harm to the environmentmay be corrosive, flammable, or explosive. Examples of toxicmaterials are carbon monoxide (CO), sulfur dioxide (SO2), and theoxides of lead and mercury.
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Examples of substances that harm the environment includewastes disposed of improperly by industries, non-biodegradablematerials, like plastic, thrown just anywhere; and excessivecarbon dioxide (CO2) introduced into the atmosphere.
Problems caused by hazardous substances are twofold: first,they cause a wide range of harmful effects on human health suchas cancer, damage to the brain, liver, kidney, bone marrow,embryo, skin, gastrointestinal organs, and to the central nervoussystem; second, these substances can cause long-term orpermanent damages to ecosystem. For instance, toxic substancesdumped into the water system can cause long-term damage tomost of our rivers and lakes.
We classify pollution into four types: air pollution, waterpollution, land and soil pollution, and noise pollution.
GUIDE QUESTIONS
Name some hazardous substances emitted by vehicles thatrun on gasoline or diesel fuel. What possible damage can theycause to humans?
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
§2. AIR POLLUTION
Substances that pollute the air are generally of two types. Thefirst types of air pollutants are those that are directly harmful to
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humans. They include toxic materials emitted by factories andmotor vehicles. The second types of pollutants are those thatdamage the environment and possibly alter the earth’s climate.
Figure 4.1: Environmental pollution
1. Toxic air pollutants
Toxic air pollutants include oxides of sulfur and nitrogen,carbon monoxide, volatile organic compounds (VOC), leadoxide, and benzene.
The main source of toxic pollutants is the burning of fossilfuels like gasoline, diesel, and petroleum in power plants,factories, and motor vehicles. Burning of trash also producestoxic pollutants.
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Figure 4.2: Burning tires harm to air environment
These pollutants are considered toxicants because the humanbody absorbs these gases together with fine particles into thebloodstream, causing adverse health effects. The most obviouseffects are:
1. Breathing difficulties.
2. Increased susceptibility to respiratory infection.
3. Development of chronic lung disease.
4. Worsening of existing heart and lung diseases.
5. Fetal defects and various kinds of cancer.
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Figure 4.3: Health effects by environmental pollutants
2. Contributors of common air pollutants
The urban and industrialized areas in the world are thegreatest contributors of air pollution. Knowing that pollutantsare the causes of many bad effects on human health, theseshould be main causes for alarm by the people in general and bythe government in particular. As experienced by the UnitedStates, Japan, and the European countries, emission control costsare high, but still, control measures must be undertaken.
Otherwise, the cost of man-hours, health care,unproductively, and shorter life span will be more staggering.UNEP and WHO suggested a gradual introduction, and propermaintenance of factories and power plants.
GUIDE QUESTIONS
1. Explain the two types of air pollution.
……………………………………………………………………………
……………………………………………………………………………
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……………………………………………………………………………
……………………………………………………………………………
2. Is air pollution in your area serious? If it is, do you knownif you or some of your neighbors have suffered from of it? Whatsuggestions can you give?
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
3. Do you know of some steps that the government has takento reduce air pollution, especially in the Ho Chi Minh City?How effective are they?
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
4. What are the forms of air pollution that can easily beavoided?
5. Enumerate some general effects of acid rain on theenvironment.
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
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6. Explain the greenhouse effect.
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
7. Cite some possible consequences of an increase in globaltemperature.
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
§3. LAND AND SOIL POLLUTION
There are two principal sources of wastes responsible for theland and soil pollution. The first one is the solid waste whichcomes from mining operations. It includes direct waste from themining of minerals and fossil fuels and those associated with themining and processing industries. Strip mining not onlyproduces mineral waste that pollutes the soil and streams butalso leaves huge scars on the land. The loosening of the soilleads to erosion during heavy rains, causing sediments to settleat the bottom of rivers and lakes. Erosion also adds to thedeterioration of the land, making it unfit for agriculture. It alsomakes the water turbid-cloudy, thick, and dense.
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Figure 4.4: Pollutants harm to the environment
Another type of solid waste is the by-products of agriculture.It includes animal manure and wastes from slaughtered horsesand from all forms of crop harvesting. These wastes aregenerally less polluted because they are spread over wide areas.Also, they are biodegradable, meaning, they return to the soil asnutrients of plants. In excessive amounts, they emit bad odor,which is almost intolerable to human beings.
GUIDE QUESTION
1. What are the major sources of water pollution in Ho ChiMinh City? Do you know if something is being done to reduce it?
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
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2. Do you know of other rivers and lakes affected by soilerosion? Where does the eroded soil come from?
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
§4. RADIATION AND ITS HARMFUL EFFECTS
Radiation is the general term used to refer to a variety of raysto which life on earth is exposed to. These include visible light,infrared and ultraviolet rays, X rays, cosmic rays, and rays fromradioactive materials.
In a wide sense, any result of radiation energy to a livingorganism is a biological effect of radiation. This includes normaleffects like photosynthesis on plants and vision in animals andalso the injurious effect burns, anemia, and cancer on humansand animals.
1. Historical background
When X rays were discovered by the German physicistWilhelm Conrad Roentgen in 1895, the focus of attention wasits possible applications, especially in the field of medicine. Theharmful effects were observed one year later. In 1896, ElihuThomas exposed one of his fingers to X rays and observed theburns caused by these.
In the same year, the famous American inventor, ThomasAlva Edition, observed the effects of X rays exposure on one of
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his assistants, Clarence Dally. Dally hair fell out and his scalpbecame inflamed. Eight years later, he developed severe ulcerson both hands and arms. They became cancerous and eventuallycaused his death.
The harmful effects of radioactivity were also observed byPierre Curie, a French chemist and one of the great scientists, in1906. Burns were produced on the parts of the body exposed toradiation. In 1925, a number of women exposed to paintcontaining radium became ill with anemia and had lesions in thejawbone and mouth. Some of them developed bone cancer later.
Ernest Lawrence - an American physicist who invented thecyclotron, a rich source of neutron - exposed rats to this deadlyradiation. He found that fast neutrons are 21/2 times moreeffective in killing them then slow neutrons.
Neutron radiation harmed and killed many people inHiroshima, Japan, when an atomic bomb was dropped there in1945. A study was conducted on several hundred pregnantwomen who survived the Hiroshima and Nagasaki bomb blasts.Their children were medically observed for more than 20 years.Many of them had heads smaller than the normal size, and therewas a significant increase in the number of mentally retardedchildren.
2. Specific harmful effects of radiation
There are many sources of radiation that may cause injury tohuman beings. The natural sources, like cosmic rays and naturalproducts like granite and monazite sands (an important source ofthe element thorium), give dosage that are very safe to humans.
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The artificial sources like medical X rays, high - voltagepower supplies, television sets, and luminous dial watches givesignificant dosage but the effects do not show until after manyyears. These effects may include lower blood counts, temporarysterility, skin irritations, and on rare occasions, cancer.
Figure 4.5: Harmful effect of radiation
The very serious health effects come from very massivedozen of radiation from nuclear reactor leaks and explosions ofnuclear weapons; such as:
The effects of the Hiroshima and Nagasaki explosions andlately, the Chernobyl disaster attested to the veracity of theseestimates. Although less damaging, the effects of the nucleartests in the Nevada desert were also well documented.
The bomb that was dropped in Hiroshima killed more than140.000 of its 255.000 inhabitants, and more deaths occurredlater from radioactive radiation. The effects of the Nagasakiblast were similar to that of Hiroshima.
In Chernobyl, Ukraine, four nuclear reactors used ingenerating electricity exploded in April of 1986. The explosion
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released between 50 and 100 million curies of radioactivematerial into environment. Within a few months, 29 people diedof radiation poisoning and 200 other were estimated to developcancer in later life. The eventual toll of the nuclear accident hasbeen estimated to be as high as 135000 cancer cases and 35000deaths.
From 1951 to 1962, the United States exploded 126 atomicbombs into the atmosphere at the Nevada test sites. Somecivilians and military personnel working at the test sitesdeveloped disorders like cancer, heart disease, thyroiddysfunction, and diabetes. The same thing happened to people insouthern Utah where winds from the test sites carriedradioactive material that affected a lot of people. Tests weresubsequently underground to minimize radiation effects andrecently, testing of atomic weapons was altogether halter.
GUIDE QUESTION
1. What types of radiation are useful to human? What typesare harmful?
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
2. What type of radiation may be useful and harmful at the sametime?
……………………………………………………………………………
……………………………………………………………………………
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……………………………………………………………………………
……………………………………………………………………………
3. What events in the past resulted in many deaths due tomassive exposure to radioactive materials?
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
§5. POLLUTION REDUCTION
There is a universal concern for doing something about theproduction and disposal of hazardous substances. Leadingindustrialized countries and some leading industrial companieshave initiated serious efforts to reduce pollution.
1. Recycling
How to handle society’s toxic chemical waste now ranksamong the top environmental issues in most industrial countries.Without concerned efforts to reduce, recycle, and reuse moreindustrial wastes, the quantities produced will overwhelm eventhe best treatment and disposal systems.
The process of converting materials into new products thatmay or may not resemble the original material is known asrecycling.
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Figure 4.6: The conception of recycle
For example, old newspapers may be recycled into newsprintpaper, board for packing, and constructional materials forroofing and insulation.
The benefits of recycling include the following:
1. It reduces waste.
2. It lowers energy, water, and primary raw materialrequirements.
3. It reduces both air and water pollution.
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Imagine the number of trees that would be saved by recyclingnewspapers. And imagine the amount of trash that would haveto be disposed of if plastics, glass, and cans were not recycled.
Japan is the leading country that undertakes recycling. Thecountry recycles or reuses about 50 percent of its solid wastes,compared with only 11 percent of the United States and 15percent of Germany.
Moreover, after burning 23 percent of Japan’s trash in waste-to-energy facilities, only 27 percent remains to be disposed of inlandfills and by other means. In contrast, 83 percent of solidwaste in the United Stated and 55 percent of solid waste inGermany are disposed of by similar means.
Table 4.1: Solid waste management in the United Stated,Japan and Germany
Type UnitedStates
Japan Germany
Recycled or reused 11 50 15
Waste-to-energy 6 23 30
Landfilled or others 83 27 55
Total 100 100 100
Furthermore, Time magazine, in its January 2, 1989, issue,reported that Japan, in 1988, recycled 50 percent of its wastepaper, 55 percent of its glass bottles, 66 percent of its beverage
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and food cans, and converted much of the remaining trash intofertilizers, fuel gases, and recycled metals.
Part of the success of Japan’s recycling program is the whole-hearted cooperation of the citizens. The Japanese separate theirtrash into six classifications to simplify recycling. In contrast,the United Stated in 1986 recovered only 23 percent of its paperproducts, 9 percent of its glass, and 25 percent of its aluminum.
Several countries have followed the Japanese. Glassrecycling is fast growing in Europe. The cities of Rome, Vienna,and Madrid have put up recovery plants producing metals, glass,paper, plastics, fibers, and other products.
Some third world countries, although on a limited scale, havesimilarly ventured into recycling. In India, more than a third ofurban waste is being composted to produce methane gas, fuelpellets, fertilizers, and animal feeds. China, specifically the cityof Shanghai, processes and sells more than 10 percent of itswaste for biogas production, fertilizers, and brick and cementmanufacture. The city also reprocesses many materials likemetals, rubber, plastics, paper, glass, and waste oil.
2. What you can do
The following are things that you can do at home, in school,or in the community to help in the reduction of pollution:
1. Help keeping your school free from unwanted garbagethrough proper disposal.
2. Help organize or join campaigns in your community toinform the public of the hazards posed by pollution. Forexample, tricycle drivers may not know that the noise
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produced by their engines could permanently impair theirsense of hearing.
3. Minimize the use of pesticides at home. If you must usethem, minimize the potential hazards by (a) making surepeople and pets are out of the area during the applicationand (b) not applying near streams and ponds.
4. Find out what companies are major contributors topollution. Do not patronize their products and convinceothers to do the same.
5. Separate wastes that can be recycled. Sell them to localdealers or give them to garbage collectors for their extraincome.
6. Help minimize the amount of waste produced in yourhome. For example, use less plastic wrappers and sell orgive old newspapers to dealers who in turn sell them forrecycling.
7. Volunteer to help in the information campaign tominimize pollution through proper waste disposal.
8. Generate enthusiasm about programs that wouldminimize air, water, land, and noise pollution.
9. Eat fewer animal products and consume more grains,vegetables, and fruits that require less energy to produceand therefore create less pollution.
10. Urge your parents to buy household items and appliancesthat contain no, or less, pollutants. Read the labelscarefully before buying.
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11. Plant fast-growing trees especially around your house.They provide shade during sunny days and absorb carbondioxide in the air. They therefore help counteract thegreenhouse effect.
12. By reducing energy consumption, you will help lessenenvironmental damage. The energy you use may comefrom burning fossil fuels like gas, oil, or, coal. Lessenergy used means less burning of these fossil fuels.
13. Economize in the use of materials that contribute to thedepletion of natural resources. For example, by using lesspaper, which is a wood product, you help reduce the needfor cutting trees.
GUIDE QUESTIONS
1. Cite government efforts to reduce pollution.
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
2. Explain the good side and the bad side of burning dryleaves under fruit-bearing trees, like mango.
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
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3. What materials are being recycled in Vietnam?
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
4. How is garbage (solid waste) disposed of in yourcommunity? Is it the good way?
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
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VOCABULARY
Recycling: Processing of material into new products thatmay or may not resemble the original material.
Toxic substance: Substance poisonous to human beings andanimals.
CHOOSE THE BEST ANSWER FOR THE FOLLOWINGQUESTIONS
1. How many types of pollution do people classify?a) 3b) 4c) 5d) 6
2. Toxic substances can cause ……………….. to ecosystem.a) short-term damagesb) long-term damagesc) permanent damagesd) short-term, long-term and permanent damages
3. Substances that pollute the air can ………………..a) directly harmful to humanb) damage the environmentc) directly harmful to human and damage the
environment
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d) not directly harmful to human and not damage theenvironment
4. Which toxic materials are directly harmful to human?a) The toxic materials are emitted by the
photosynthesisb) The toxic materials are emitted by factories and
motor vehiclesc) The toxic materials are emitted by the process of
respirationd) The toxic materials are emitted by the algae bloom
5. Toxic air pollutants include ………………..a) oxides of sulfur and nitrogenb) carbon monoxide and lead oxidec) volatile and organic compoundsd) sulfur oxide, nitrogen oxide, carbon monoxide, lead
oxide, volatile and organic compounds6. The main source of air pollution is ………………..
a) burning of fossil fuelb) burning of trashc) insanitaryd) acid rain
7. Health effects by environmental pollutants are ……………a) Breathing difficulties and increasing susceptibility to
respiratory infection.b) Developing of chronic lung disease and fetal defects
and various kinds of cancer.
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c) Decreasing susceptibility to respiratory infection.d) Decreasing the serious diseases
8. The principal sources of wastes which are responsible forthe land and soil pollution are ………………..
a) the solid wastes which come from mining operationsb) the municipal solid wastes and the solid wastes
which come from mining operationsc) the solid wastes which come from mining operations
and the by-product of agricultured) the municipal solid wastes and the by-product of
agriculture9. Which wastes from the mining operations can make the
land and soil pollution?a) wastes from the mining of mineralsb) wastes from the mining of fossil fuelsc) wastes that associated with the mining and
processing industriesd) wastes that associated with the mining and
processing industries and the wastes from the miningof minerals and fossil fuels
10. Some effects of erosion are ………………..a) making the soil become deteriorative and waterlessb) making the soil become fertile and deteriorativec) making the soil become waterless and fertiled) making the soil become fertile and erodent
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11. Which wastes is the by-product of agriculture?a) animal manureb) wastes from slaughtered horsesc) wastes from all forms of crop harvestingd) animal manure, wastes from slaughtered horses and
wastes from all forms of crop harvesting12. When was X-ray discovered?
a) 1885b) 1890c) 1895d) 1900
13. Who invented the cyclotron?a) Ernest Lawrenceb) Elihu Thomasc) Wilhelm Conrad Roentgend) Thomas Alva Edition
14. Problems caused by hazardous substances are ……………a) harmful effects on human healthb) short-term damages to ecosystemc) long-term or permanent damages to ecosystemd) harmful effects on human health, short-term, long-
term or permanent damages to ecosystem15. Pollution can be classified into ……………..
a) two typesb) three types
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c) four typesd) five types
16. Substances that pollute the air can be classified into ……...a) two typesb) three typesc) four typesd) five types
17. Burning of fossil fuels like gasoline, diesel, and petroleummostly ………………..
a) pollutes to water environmentb) pollutes to air environmentc) pollutes to soil environmentd) pollutes to land
18. Pollutants are considered toxic because ………………….a) the human body absorbs these gasesb) the human body absorbs fine particles into the
bloodstreamc) they are causing adverse health effectsd) because the human body absorbs these gases
together with fine particles into the bloodstream,causing adverse health effects
19. What are the greatest contributors of air pollution?a) the urban and industrialized areas in the worldb) deforestation and greenhouse effectc) acid rain and deforestation
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d) greenhouse effect and acid rain20. What is the form of air pollutants that can easily be avoided?
a) sulfur oxideb) carbon monoxidec) organic compoundsd) nitrogen oxide
21. There are ……………. of wastes responsible for the landand soil pollution.
a) two principal sourcesb) three principal sourcesc) four principal sourcesd) five principal sources
22. Animal manure and wastes from slaughtered horses andfrom all forms of crop harvesting are ………………..
a) by-product of industryb) by-product of agriculturec) by-product of domesticd) by-product of agriculture, industry and domestic
23. By-products of agriculture are less polluting because …….a) they are biodegradableb) they are able to return to the soil as nutrients of
plantsc) they are spread over wide areasd) they are biodegradable, spread over wide areas and
able to return to the soil as nutrients of plants
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24. X rays were discovered bya) Elihu Thomasb) Wilhelm Conrad Roentgenc) Thomas Alva Editiond) Clarence Dally
25. There are ..…………….. of radiation that may cause injuryto human beings
a) two sourceb) three sourcesc) four sourcesd) five sources
26. What are the natural sources of radiation?a) cosmic rays, granite and monazite sandsb) medical X raysc) high - voltage powerd) luminous dial watches
27. The effects of the Hiroshima and Nagasaki explosions due to …a) nuclear testsb) nuclear weaponsc) nuclear reactor used in generating electricityd) nuclear accident
28. Which type of radiation may be useful and harmful at thesame time?
a) nuclear testsb) nuclear weapons
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c) nuclear reactor used in generating electricityd) nuclear accident
29. Which event dues to massive exposure to radioactivematerials?
a) The bombs were dropped in Hiroshima andNagasaki.
b) Nuclear reactor used in generating electricityexploded in Chernobyl.
c) 126 atomic bombs into the atmosphere at the Nevada testsites.
d) The bombs in Nevada test sites, in Hiroshima andNagasaki and nuclear reactor used in generatingelectricity exploded in Chernobyl.
30. The process of converting material into new products thatmay or may not resemble the original material is called …..
a) recyclingb) reducingc) reusingd) recycling, reducing and reusing
31. The substance that is poisonous to human beings andanimals is called …….
a) toxic substanceb) solid wastec) waste waterd) hazardous waste
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32. Recycling is beneficial because ……………..a) it reduces wastesb) it lowers energy, water and primary raw material
requirementsc) it reduces both air and water pollutiond) it lowers energy, water and primary raw material
requirements, therefore, it reduces wastes, air andwater pollution
33. Which gases contribute to greenhouse effect?a) carbon dioxide and methaneb) methane and nitro dioxidec) nitro oxide and nitro dioxided) carbon dioxide, methane, nitro oxide and nitro
dioxide34. Many famous buildings have been deteriorated by ………..
a) acid rainb) ozone depletionc) greenhouse effectd) acid rain, ozone depletion and greenhouse effect
35. Which activity makes a great contribution to air pollution?a) Deforestationb) Acid rainc) Industryd) Greenhouse effect
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36. Gases produced by the decay of organic matter, especiallymanure and crop residues are ………………
a) greenhouse gasesb) biogasc) natural gasesd) artificial gases
37. Biological control is ……………..a) the use of natural parasites and bacteria to control
pestsb) the use of predators to control pestsc) the use of predators, natural parasites and bacteria to
control pestsd) the use agrochemicals to control pests
38. Amount of organic materials that is available at eachtrophic level is ………….
a) food chainb) energy contentc) energy pyramidd) biomass pyramid
39. Biome is ……………..a) a large geographical area with characteristic life
formsb) amount of organic materials in plants or animalsc) the object that can be acted upon by micro-
organisms
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d) organism that is self-nourishing40. The process of decaying plants, animals and other organic
matter in the presence of air to obtain humus is called ………a) landfillingb) recyclingc) incineratingd) composting
41. The main sources of energy in the world are …………….a) oil and charcoalb) oil and natural gasc) fossil fuels and natural gasd) charcoal and natural gas
42. Choose the correct sentence:a) Humans and animals release toxic pollutants.b) Toxic pollutants cause many kinds of diseases for
humans and animals.c) Toxic pollutants causes air pollution.d) The photosynthesis makes the air polluted.
43. The urban and industrialized areas in the world are the………… contributors of air pollution.
a) greatb) greatestc) greaterd) greatly
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44. There are many sources of ……………….. that may causeinjury to human beings.
a) radarb) radiatec) radiatived) radiation
45. The old newspapers may be recycled …... newsprint paper,board for packing and construction materials for roofingand insulation.
a) tob) inc) intod) on
46. The harmful effects of radioactivity …….. observed byPierre Curie, a French chemist, in 1906.
a) isb) arec) wasd) were
47. Some ….. of X rays may include lower blood counts,temporary sterility, skin irritations and cancer.
a) effectb) effectsc) resultd) results
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48. The by-product ….. agriculture includes animal manure and thewastes from slaughtered horses and from the crop harvesting.
a) ofb) fromc) tod) in
49. The strip mining not only produces ….. waste that pollutesthe soil and streams but also leaves huge scars on the land.
a) mineb) minerc) minerald) mineralogical
50. Nitrogen is the ……….. because the human body absorbsit together with fine particles into the bloodstream, causingadverse health effects.
a) toxicb) toxicityc) toxicantd) toxication
51. The pollutants that are ………. harmful to humans includetoxic materials from the factories and motor vehicles.
a) directb) directlyc) indirectd) indirectly
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52. Substances that are poisonous to human beings andanimals are called ………………..
a) toxicb) toxicityc) toxicantd) toxication
53. The main source of toxic pollutants is the burning of fossilfuels like gasoline, diesel and petroleum ….. power plants,factories and motor vehicles.
a) inb) onc) ofd) at
54. Which causes make the land degradation?a) soil erosionb) desertificationc) loss of fertilityd) soil erosion, desertification and loss of fertility
55. The main causes make air pollution are ………………..a) acid deposition and greenhouse gas build-upb) greenhouse gas build-up and ozone layer depletionc) acid deposition, greenhouse gas build-up and ozonelayer depletiond) respiration and photosynthesis
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56. Identify the error underlined word or phrase of thefollowing sentence: “These pollutants considered toxicbecause the human body absorbs these gases together withfine particles into the bloodstream, causing adverse healtheffects”.
a) consideredb) absorbsc) intod) causing
57. Identify the error underlined word or phrase of thefollowing sentence: “Radiation is the general term use torefer to a variety of rays to which life on the earth isexposed”.
a) generalb) use toc) to whichd) is exposed
58. Identify the error underlined word or phrase of thefollowing sentence: “The process of converting materialsinto new products that may or may not resemble theoriginal material is know as recycling”.
a) intob) resemblec) knowd) recycling
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59. Identify the error underlined word or phrase of thefollowing sentence: “The loosening of the soil lead toerosion during heavy rains, causing sediments to settle atthe bottom of rivers and lakes”.
a) looseningb) leadc) duringd) causing
60. Identify the error underlined word or phrase of thefollowing sentence: “A hazard substance includes anysubstance that poses a threat to human health or theenvironment”.
a) hazardb) includesc) posesd) human health
61. The following pollutant is not contained in the vehicularexhaust emissions:
a) leadb) ammoniac) carbon monoxided) particulate matter
62. Health problems related to air pollution include:a) coughingb) asthmac) bronchitis
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d) coughing, asthma and bronchitis63. Water has an adverse effect on both the environment and health.
What are the main sources of water pollution in Vietnam?a) municipal wasteb) bathingc) industrial discharged) municipal waste and industrial discharge
64. Which are highly responsible for eutrophication of waterbodies?
a) phosphorus and carbonb) nitrogen and phosphorusc) iron and arsenicd) arsenic and phosphorus
65. Of the following indications of the health of water body,which is the most widely accepted means of measuringhow polluting an effluent is?
a) BODb) CODc) Chloroform contentd) pH
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CHAPTER 5: SUSTAINABLEDEVELOPMENT AND THE FUTURE
After studying this chapter, you should be able to:
1. Explain why the balance of nature was altered onlyrecently
2. Relate how humans were able to control nature
3. Enumerate the consequences of controlling nature
4. Comprehend the pressure on the environment, resultingfrom rapid increase population
5. Understand the problem of uneven distribution of wealth
6. Distinguish the problem of solutions offered to problemimpacts in the world.
§1. THE GLOBAL ENVIRONMENTAL SITUATION
Scientists have estimated that the earth is more than fourbillion years old, and it will continue to exist for around thesame period of time. Life on earth as we know it today cameinto being around three billion years ago. Based on fossils foundaround the world, human beings have inhabited the earth formore than two million years. All this time, nature and life onearth lived in equilibrium. There was no major disturbancewhich could alter the balance of nature. This was true up toaround 2000 years ago.
At around that time, people began to disturb the environmentin such a manner as to effect the global environment.
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The rampant and reckless cuttings of trees in virgin forestshave resulted in soil erosion, flooding, expansion of deserts, anddestruction of lakes. Overexploitation of other natural resources,like fish and other aquatic resources, has resulted in alarmingdecrease of catch worldwide.
Too much use of fossil fuels, like oil and other minerals, hasdepleted these natural resources to much an extent that thesupply may not last for another one hundred years. It takesmillions of years to form oil from the fossils of plants.
The industrial revolution has produced all kinds of hazardousmaterials that harmed the environment-pollution of the air,water, land, and the atmosphere. Many of these hazardoussubstances are also toxic to humans as well as to other animals.
To be fair to those concerned, all these were the unwantedeffects of a desire to improve the quality of life - a very nobleintention. In fact, as direct consequences of scientificbreakthroughs in many fields of human endeavor, people havein many ways succeeded in this worthy ambition. People were,to a certain extent, able to control nature. By applying what theyhave discovered about the laws of nature, they were able toconquer darkness though electric bulbs and fluorescent lamps,hot weather conditions through electric fans and airconditioners, and cold weather through heaters. Through modernmedicines and sanitation, they were able to control the spread ofdiseases; through modern agriculture, they were able to producemore food containing better nutrients.
The overall result of better living conditions, bettersanitation, and better nutrition includes rise in life expectancy
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and low infant mortality. The net effect is rapid increase inpopulation.
INSIGHTFULNESS
The luxurious life-style of the rich and famous contributes toenvironmental degradation.
According to the United Nations Statistical Yearbook (1988),the doubling of the population between 1950 and 1986 wasaccompanied by grain consumption of 2.6 times, energy use of3.7 folds, and quadruple economic output and sevenfoldincrease in the production of manufactured goods. All thesewere accompanied by more than nine fold increase in water, air,and land pollution.
INSIGHTFULNESS
Most developed countries have zero or very, very lowpopulation growth rate.
But the irony is, situation differ from region to region andcountry to country. Because of the wide gap between the richand the poor nations, the benefits of these increases do not applyequally among people of the world.
For instance, despite overall rise in food production in theworld, nearly a billion people (1/6 of the world’s population) donot consume enough calories for an active working life. Andbecause of less scientific agricultural practices combined with ahigh population growth, the grain production per person isdeclining in Africa, India, and Latin America.
In the less-developed countries, it is estimated that only halfof the people have access to safe drinking water. Because of
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this, around 10 million people worldwide die due to water-bornediseases. In the industrialized countries, agriculture and industryare rapidly using up groundwater. Deforestation in many areasaggravates the situation. It prevents the staring of groundwater.
The main sources of energy in the world are fossil fuels (oiland charcoal) and natural gas. At the beginning of their use,many people thought that the supply is practically inexhaustible.But since World War II, energy consumption has increasedmore than four times. Scientists have since then changed theirpredictions. They now predict that oil reserves will be used up inless than 50 years, and natural gas by around 60 years.
Since the introduction of polluting materials by humans, thequality of air, soil, and water has deteriorated. Humans, animals,and plants have been affected. Toxic pollutants cause many kindsof illnesses in humans and animals. Oxides of nitrogen and sulfur,the ozone, and other pollutants are causing acid rain that lowercrop yield and damage millions of hectares of forests, especiallyamong the industrialized countries. Increase in atmosphericcarbon dioxide is casing the so-called greenhouse effect. This ispredicted to alter the earth’s climate and raise ocean levels, withdisastrous consequences to coastal towns and cities.
WARM UP
Most of the time, nature is friendly. It seldom shows its fury.When it does, it is uncontrollable.
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Table 5.1: Global problem impacts and problem causes
Problem Impacts
Problem causes
Unsustain-ablepopulation
growth
Poverty andInequality
Unsustain-able foodproduction
Unsustain-ableenergy use
Unsustain-able
industrialproduction
Unmet basic human needs for safe water, food,shelter, health care, education, employment, etc. ■ ■ ☼ ► ►
Species depletion (extinction of plants andanimals, habitat degradation) ■ ■ ♣ ☼ ☼
Land degradation: soil erosion, desertification,loss of fertility ■ ♣ ■ ♣ ►
Depletion of nonrenewable energy and minerals ♣ ► ♣ ■ ♣Depletion of fresh water (groundwater and surfacewater) ♣ ► ■ ► ♣
Water pollution: chemical and bacterialcontamination of groundwater and surface water ♣ ☼ ♣ ☼ ■
Air pollution: urban air pollution, acid deposition,ozone layer depletion, greenhouse gas buildup ♣ ☼ ☼ ■ ■
Conflict and war: domestic and international ♣ ♣ ☼ ☼ ☼
Source: W. Lorson, ed., The Global Ecology handbook, 1990
■: Very important cause ♣: Moderately important cause
☼: Less important but insignificant cause ►: Unimportant or insignificant cause
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It can be seen from above table that unsustainable populationgrowth is a very important cause of three problem impacts and amoderately important cause for the five other problem impacts.
It is very difficult to meet the basic human needs for food,safe water, shelter, health care, education, and others by toorapid increase in population without straining the environment.And an unrestrained exploitation of our natural resource resultsin the loss of virgin forests and soil fertility, soil erosion ofdeserts. These in turn deprive many animals and plants of theirnatural habitat. Extinction of many animal and plant species is adirect consequence.
In order to support an ever-increasing population, more andmore factories must be put up. Industry must be expanded and ofcourse pollution follows, the consequences of which are alreadyenumerated above.
The probability of conflict between ethnic groups and nationsis increased with unsustainable population growth. They mayfight over needs resources, like oil and water. Or, they may fightfor territories needed by their increasing number. The resultingmisery and human sufferings brought about by war are too wellknown.
The possibility of poverty and unequal distribution of wealthbecomes greater with unsustained population growth. Foodproduction may not be able to keep up with the increase in thenumber of consumers.
Geographically, the earth is divided into nations with varyingresources and with varying population densities and varyingdegrees of industrialization. In short, some countries are wealthier
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than others. And even in the same country, the structure of societyvaries; there is a very wide gap between the rich and the poor.Cutting more trees and over fishing in order to survive are likelyexamples of this.
GUIDE QUESTIONS
1. Explain the main reasons why humans drastically alter theglobal environment.
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
2. Explain some of the consequences of altering the balanceof nature.
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
3. Enumerate more beneficial effects of humankind’s beingable to control nature.
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
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4. Why is the increase in food consumption, energy use, andeconomic output much greater than the increase in population?
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
5. Cite policies by some governments around the world toaddress the problem of inequality of life among peoples of theworld.
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
§2. SUISTAINABLE DEVELOPMENT
The past 20 years have seen a growing realization that thecurrent model of development is unsustainable. In other wordswe are living beyond our means. From the loss of biodiversitywith the felling of rainforests or over fishing to the negativeeffect our consumption patterns are having on the environmentand the climate. Our way of life is placing an increasing burdenon the planet - this cannot be sustained.
The increasing stress we put on resources and environmentalsystems such as water, land and air cannot go on forever.Especially as the world's population continues to increase and
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we already see a world where over a billion people live on lessthan a dollar a day, more than 800 million are malnourished, andover two and a half billion lack access to adequate sanitation.
Some people started realizing the development andenvironmental protection are inequality; such as:
Successful economic development and environmentalprotection go hand in You cannot have one without theother. (Former U. S President George Bush)
Achieving sustainable economic growth will require theremodeling of agriculture, energy use, and industrialproduction after nature’s example. (Jessica TuckmaMathews - World Resource Institute)
Our global future depends upon sustainable development.It depends upon our willingness and ability to duplicateour intelligence, ingenuity, and adaptability - and ourenergy - to our common future. This is a choice we canmake. (the Report of the world commission onenvironment and development)
Some countries are more developed than others in terms ofagriculture, industry, education, health services, and otheraspects of development. Most of the countries in WesternEurope are more developed than those of Eastern Europe.Similarly, the countries in North America are more developedthan those of Central and South America. Likewise mostcountries in Africa are less developed. Some countries in Asialike Japan, Korea, Taiwan, and Singapore are more developedthan others like the Philippines, Malaysia, Indonesia,Bangladesh, India and Vietnam.
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The People’s standard of living also varies from one countryto another. Needless to say, those from the developed countries,on the average, have higher standard of living.
Some researches show that the less developed countries, asmeasured by their per capita income, have higher birth rates,lower life expectancy, poorer dwellings, lower birth weights,lower literacy, less number of doctor and nurses per unitpopulation, and consume less energy and fewer calories.
A widely-used and accepted international definition ofsustainable development is “development which meets the needsof the present without compromising the ability of futuregenerations to meet their own needs”. This means developmentwithout permanent damage to the ecological system.
Sustainable development means using the natural resourcesonly to a certain extent so that they will be able to recover. Itfurther means that population should either be help to aminimum or be stopped altogether. This is the same as sayingthat sustainable development must not endanger the atmosphere,water, soil, and ecosystem that support life on earth. Moreover,sustainable development requires societies to meet human needsby increasing productive potential and by ensuing equitableeconomic, social, and political opportunities for all.
To accomplish such an objective might curtail some kind ofupheaval in some societies around the world. Instance, in acountry where the economy and the means of production arecontrolled by a few rich families, where the middle class inweak and a great majority of the people are poor, a restructuringof society might be needed.
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In order that the definition of sustainable development is fullyunderstood and the proposed solutions to the problem impacts,as mentioned earlier, be adequately addressed.
Some solutions for achieving sustainable development as
Reducing poverty: Reducing poverty implies better health,better nutrition, longer life expectancy, and improved literacy.Reducing inequalities suggests better employment prospects andbroadening of opportunities for those who have less in life.These are important solutions to the problems of basic humanneeds and habitat degradation.
Making agriculture: Making agriculture sustainable requiresdrastic reduction in soil erosion, maintenance of arable lands,and a drastic decrease in harmful farming practices like the useof toxic chemicals. Systems for reducing soil erosion should bedevised. There should be strict policy in the conversion of arablelands into roads and subdivisions, and for industrialdevelopment. Maintaining soil fertility though intercropping andthe trees and the use of nontoxic fertilizers will go a long waytoward solving the problem of pollution.
Forest protection: Forest protection is not easy for a countrywhere there are so many poor people. They need the trees andthe land for survival. Government must have a viable programfor reforestation. Success in this degradation will effectivelyreduce freshwater depletion, slow down land degradation, andprevent periodic flooding.
Wise use of energy: Wise use of energy includes changing thelife style of well-to-do people like using smaller car, less use ofair conditioners, and less light in the homes. It also includes
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energy saving measures from the government: regulating speedlimits, requiring the installation of energy saving devices inoffices, and developing more renewable energy source likehydro electronic power plants. The net effect of the measureswould be energy conservation and less pollution.
Supply of fresh water: The supply of fresh water in the worldis critical. With very high demand from industry and people,aggravated by deforestation, the supply has greatly diminished.In addition, because of pollution, the quality of the water hasdeteriorated. The need to conserve fresh water is of utmostimportance to support a growing population and to provideirrigation to agricultural crops.
CHOOSE THE BEST ANSWER FOR THE FOLLOWINGQUESTIONS
1. ……………….. means using the natural resources only toa certain extent so that they will be able to recover.
a) Unsustainable population growthb) Problemsc) Globalizationd) Sustainable development
2. Sustainable development ……………… the atmosphere,water, soil and ecosystem.
a) must not endangerb) is dangerous
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c) can developd) can’t develop
3. Forest protection is one of the solutions of ………………..a) environment protectionb) sustainable developmentc) environment protection and sustainable developmentd) industrial revolution
4. Some of solutions for achieving sustainable developmentare …….
a) reducing poverty and making agricultureb) protecting forestc) wising use of energy and supplying of fresh waterd) reducing poverty and making agriculture, protecting
forest and wising use of energy and supplying offresh water
5. Reducing poverty implies ………………..a) better health and nutritionb) longer life expectancyc) better health, nutrition and longer life expectancyd) soil degradation
6. What does making agriculture sustainable require?a) reduction in soil erosionb) maintenance of arable landsc) decreasing the use of toxic agro-chemicals
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d) reduction in soil erosion, maintenance of arablelands and decreasing the use of toxic agro-chemicals
7. Deforestation means ………………..a) cutting down forest trees for firewood and
agriculture developmentb) planting forest treesc) afforestingd) sell firewood for life
8. The benefit of reforestation is ………………..a) reducing freshwater depletionb) reducing land degradationc) preventing periodic floodingd) preventing periodic flooding and reducing
freshwater depletion and land degradation9. Use of hydro electronic power is a way of ………………..
a) saving moneyb) wise use of energyc) developmentd) using energy
10. Wise use of energy includes ………………..a) less use of air conditioners and less light in the homeb) less use of cars and developing renewable energysourcec) less use of air conditioners and cars and less light in
the home and developing renewable energy sources
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d) use unsustainably the energy sources.11. Which cause makes the supply of fresh water diminished?
a) deforestationb) high demand from industry and deforestationc) water protectiond) greenhouse effect
12. The quality of the water has deteriorated by ………………a) pollutionb) sustainable developmentc) less use of air conditionersd) afforesting
13. The components of atmosphere include ………………..a) nitrogen, oxygen, hydrogen and steamb) carbon oxide, ozone and methanec) inert gas, carbon oxide, ozone and methaned) nitrogen, oxygen, hydrogen, steam, carbon oxide,
ozone, methane and inert gas14. Choose the correct sentence:
a) Carbon dioxide is a source of water pollution.b) El-Nino makes the Earth’s temperature decrease.c) The effusive volcano causes the air pollution.d) Deforestation is a best way to protect the forest.
15. One of the principles of sustainable development is ………a) protecting the diversity of the Earth
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b) changing the personal habit.c) Managing the natural resourcesd) protecting the diversity of the Earth, changing thepersonal habit and managing the natural resources
16. People began to disturb the environment in such a manner……….. to effect the global environment many years ago.
a) likeb) asc) byd) from
17. Most developed countries have zero or very, very lowpopulation …..
a) peopleb) ratingc) growingd) growth rate
18. In the less-developed countries, it is estimated that onlyhalf …….. the people have safe drinking water.
a) inb) onc) ofd) at
19. …………. in many areas aggravates the environmentaldegradation.
a) afforestation
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b) deforestationc) forestd) forester
20. Oxides of nitrogen, sulfur, carbon dioxide and otherpollutants are …….. acid rain that lower crop yield anddamage millions of hectares of forests.
a) due tob) dued toc) resultingd) causing
21. The probability of conflict between ethnic groups andnations is increased with ……………….. populationgrowth.
a) unsustainableb) unsustainedc) sustainabled) sustained
22. Achieving sustainable economic growth will require theremodeling ……………….. agriculture, use of energy andindustrial production after nature’s example.
a) inb) onc) ofd) at
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23. Sustainable development …………….. using the naturalresources only to a certain extent so that they will be ableto recover.
a) meanb) meansc) is meantd) is meaning
24. Sustainable development requires societies to meet humanneeds ……………….. increasing productive potential andby ensuing equitable economic, social and politicalopportunities for all.
a) byb) toc) causedd) due to
25. ……………….. inequalities suggests better employmentprospects and broadening of opportunities for those whohave less in life.
a) reduceb) reducingc) reducibled) reduction
26. Making agriculture sustainable requires drastic reduction…… soil erosion, maintenance of arable lands, and adrastic decrease in harmful farming practices like the useof toxic chemicals
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a) ofb) atc) ond) in
27. Forest protection is not easy for a country …….. there areso many poor people.
a) whenb) wherec) whichd) what
28. ….. the wide gap between the rich and the poor nations, thebenefits of these increases do not apply equally amongpeople of the world.
a) Althoughb) Despitec) Becaused) Because of
29. The luxurious life-style of the rich …………….. famouscontributes to environmental degradation.
a) andb) orc) betweend) with
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30. The main sources …………….. energy in the world arefossil fuels and natural gas.
a) atb) onc) ind) of
31. Identify the error underlined word or phrase of thefollowing sentence: “The industrial revolution haveproduced all kinds of hazardous materials that polluted theenvironment”.
a) industrialb) have producedc) hazardousd) polluted
32. Identify the error underlined word or phrase of thefollowing sentence: “Oxides of nitrogen and sulfur, ozoneand other pollutants are causing acid rain that lower cropyield and damages millions of hectares of forests,especially among the industrial countries”.
a) oxidesb) lowerc) damagesd) of
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33. Identify the error underlined word or phrase of thefollowing sentence: “The possible of poverty and unequaldistribution of wealth becomes greater with unsustainedpopulation growth”.
a) possibleb) wealthc) withd) population
34. Identify the error underlined word or phrase of thefollowing sentence: “Sustainable development means usingthe natural resources only to a certain extent so that they beable to recover”.
a) meansb) usingc) extentd) be able to
35. Identify the error underlined word or phrase of thefollowing sentence: “It is very difficulty to meet the basichuman needs for food, safe water, shelter, health care,education and others by too rapid increase in populationwithout straining the environment”.
a) difficultyb) needsc) increased) straining
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36. Which among the following is most energy efficient?a) incandescent bulbb) florescent tube lightc) compact fluorescent lampd) incandescent bulb and florescent tube light
37. In rural areas, this gas can be generated and used forcooking and lighting.
a) biogasb) oxygenc) ammoniad) biogas, oxygen and ammonia
38. Wind energy is the kinetic energy associated withatmospheric air. It has been used for centuries for thefollowing operation.
a) grinding grainb) generating electricityc) running carsd) grinding grain and running cars
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GLOSSARY
Abiotic factor: Nonliving components of the ecosystemincluding physical and chemical factors such as pH of soil,temperature, and relative humidity.
Acid precipitation: Rain or snow that has lower pH thanprecipitation from unpolluted skies.
Acid rain: Moisture in the atmosphere which has beencontaminated by oxides of sulfur and nitrogen.
Active solar: Process of capturing and storing energy fromthe sun though solar panels.
Adaptation: Ability of an organism to adjust to the constantlychanging conditions of the environment.
Advanced industrial society: Post - World War II industrialsociety characterized by great rise in production andconsumption and increase energy demand.
Agricultural period: Period when people that lived in townsor villages rely on domestic animals and fields.
Algae bloom: Very rapid growth of algae in surface watersdue to increase in inorganic nutrients, especially phosphorusand nitrogen.
Alien species (also called foreign species): Speciesintroduced in new habitats.
Aquifer: Groundwater for human use.
Asthma: Lung disorder characterized by the constriction andmucus production and deposition in the bronchioles.
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Atmosphere of the earth: Layer of air surrounding the earth.
Autotroph: Organism that is self-nourishing; one that canproduce its own food.
Bacteria: Group of single-celled organisms responsible forfunctions like that decay of organic materials and nutrientrecycling.
Biodegradable: Object that can be acted upon bymicroorganisms, like bacteria and fungi.
Biogas: Gas produced by the decay of organic matter,especially manure and crop residues.
Biological control: Use of natural parasites, predators,bacteria, and others to control pests.
Biological magnification: Accumulation or increase of chemicalsubstances on organisms in succeeding higher trophic levels.
Biological oxygen demand (BOD): Measure of the depletionof oxygen in water due to bacteria decay.
Biomass: Amount of organic materials in plants or animalsfrom which energy can be derived.
Biomass pyramid: Amount of organic materials available at eachtrophic level.
Biome: Large geographical area with characteristic lifeforms; a stable community.
Biosphere: Portion of the earth and its environment withinwhich life in any of its form is manifested.
Biotic factor: Living component of the ecosystem whichincludes plants, animals, and bacteria.
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Biotic potential: Reproductive capacity of the livingcomponents of the ecosystem.
Birthrate: Average number of living births per year per 1000inhabitants in the certain place.
Bottom-up approach: Change in attitudes and values whichcan influence a change in life-style in order to solveenvironmental problems.
Cancer: Uncontrolled growth of body cells.
Canopy: Uppermost leafy covering of the forest.
Carbon cycle: Cycling of carbon between organisms and theenvironment.
Carcinogen: Chemical that causes cancer.
Catalyst: Substance that accelerates reaction of chemicals.
Cell: Basic unit of life.
Chlorophyll: Green pigment in plants involved in the processof photosynthesis.
Clear cutting: Removal of all trees in an area like a forest.
Climate: Average weather condition.
Climax community: Mature and stable community.
Cogeneration: Production of two and more forms of usefulenergy from one process.
Community: Population of plants, animal, andmicroorganisms living and interacting in a given locality.
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Composting: Process of decaying plants and animals, andother organic matter in the presence of air to obtain humus.
Coniferous biome: Forest abundant in cone - bearing trees,called conifers, which have needlelike leaves.
Conservation: Process of reducing the use of resourcesthrough recycling, decreased demand, and increased efficiencyuse.
Consumer: Organism that feeds on other organisms.
Crop rotation: Alternating crops in the fields.
Curie: Unit of radioactivity equivalent to 3.70×1010disintegration per second of any radioactive nuclides.
DDT: Organochlorine insecticide used to control pets. It isnow banned due to its harmful effects in the environment.
Death rate: Average number of deaths per year 1000population in the certain place.
Deciduous forest: Forest consisting of plants that shed offtheir leaves annually.
Decomposer (also known as microconsumer): Organismwhich breaks down nonliving organic material; example arebacteria and fungi.
Deforestation: Destruction of forest.
Denitrifying bacteria: Bacteria that convert nitrates intonitrogen gas.
Desert: Type of biome characterized by low humidity, hightemperature, and plants, and animals adapted to lack of water.
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Desertification: Formation of deserts in arid and semi - aridregions due to change in climate and overgrazing.
Detritus: Any organic waste from plants and animals.
Dinoflagellate: Small organism floating near the surface ofthe ocean that cause red tides.
Diversity: Number of different species in an ecosystem.
Dominants: Most numerous organisms in a community; theyare usually the plants.
Ecological habitat: Place where the organisms live in theecosystem.
Ecological niche: Specific function performed by anorganism.
Ecology: Division of biology that treats the relation betweenorganisms and their environment.
Ecosystem: Interaction between an organism and itsenvironment.
Ecosystem stability: State of balance or equilibrium in anecosystem.
Ecotone: Community of transition zone between two adjacentcommunities.
Endangered species: Organism that is in danger of becomingextinct.
Energy: Capacity to do work
Environment: Sun of all external forces and conditions actingon an organism or a community of organisms.
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Eutrophication: Accumulation of nutrients in a lake or ponddue to human intervention or nature causes.
Exclusion principle: Idea that no two species can occupyexactly the same niche.
Fecundity: Ability of the population to bear children.
Fission: Splitting of heavy nuclei when struck by neutrons orother subatomic particles.
Fluorocarbon: Organic molecule consisting of chlorine andfluorine covalently bonded to carbon.
Food chain: Energy pathway which proceeds from the producer tothe consumer.
Food web: Series of interrelated food chains in an ecosystem.
Fossil fuel: that which is composed of coal, gas, and soilwhich are derived from the decomposition of dead organismsafter a long time.
Frontier mentality: Kind of attitude among people to effectsthat the environment can be abused and misused.
Fusion: See nuclear fusion.
Geothermal energy: Energy derived from magma.
Grassland biome: Community where grass is abundant whiletrees are scarce and where mostly herbivores and rodents dwell.
Greenhouse effect: Rising of the average global temperaturecaused by the accumulation of the carbon dioxide and other gasesin the atmosphere. These gases trap radiant heat and prevent itsescape into space.
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Groundwater: Water below the earth’s surface.
Habitat: Place where the organism lives.
Halophyte: Plant that grows in saline or salty environment,like seaweeds and algae.
Hazardous substance: Substance that poses a threat to humanhealth and the environment.
Herbivore: Organisms that feeds directly on plants
Heterotroph: Organisms that feeds on others and cannotmanufacture its own food.
Humus: Material which consist of decaying matter andinorganic substances that result from the decomposition of deadplants and animal.
Hydroelectric power: Power produced in turbines powered byrunning water.
Hydrophytes: Plant that grows in water and permanently water -logged soil.
Insecticide: From of pesticide used to control insectpopulation.
Life expectancy: Average age at which a person is calculatedto live.
Limnetic zone: Open water zone of lakes through whichsunlight penetrates.
Littoral zone: Shallow waters along a lakeshore where rootedvegetation grows.
Magma: Molten rock beneath the earth’s crust.
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Maximum temperature: Highest limit of temperature bywhich an organism can still function.
Mesophyte: Plant of grows in moderate conditions betweenthe environmental extremes.
Microconsumer: Bacterium of fungus that carries outdecomposition.
Minimum temperature: Lower limit of temperature by whichan organism can still function or survive.
Mutation: Any damage done to the DNA or chromosomes.
Natural gas: Fuel containing about 50 to 90 percent methane.
Niche: Place where organisms live.
Nitrate: Inorganic anion containing three oxygen atoms and onenitrogen atom.
Nitrite: Inorganic anion containing two oxygen atoms and onenitrogen atom.
Nitrogen cycle: Cycling of nitrogen between the organisms and theenvironment.
Noise pollution: Unwanted sound that have harmful effectson the body.
Nuclear fission: Splitting of an atomic nucleus when struck byneutrons.
Nuclear fusion: Joining of two small atomic nuclei to from anew and large nucleus.
Nuclear power: Energy derived from nuclear fission orfusion.
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Oil: See petroleum.
Oil shale: Sedimentary rock which is finely grained andcontains an inorganic substance called kerogen.
Omnivore: Organism that consumes both plants animals.
Optimum temperature: Temperature at which the organism canfunction best.
Ozone: Molecule that contains three molecules of oxygenfound in the atmosphere and which screens ultraviolet rays.
Ozone layer (or the ozonosphere): Thin layer of ozone in the upperatmosphere which absorbs ultraviolet light and converts it to infraredradiation.
Paralytic shellfish poisoning: Effect to red tide poisoning.
Particulate radiation: That which consists of parts of atomsthat are radiated either by natural radioactive disintegration orby artificial means like the explosion of atomic bombs.
Passive solar: Capture and retention of the sun’s energywithin a building though windows and some from the heatstorage in the building.
pH: Measure of the acidity on a scale of 0 to 14.
Photosynthesis: Process of manufacturing food by greenplants in the presence of sunlight.
Physiological drought: The result when the roots of plantsbecome les permeable at low temperatures.
Pioneer community: First group of organisms that becomesestablished in an environment that was not previously occupiedby any life form.
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Pollution: That which occurs when there is a change in thephysical, chemical, or biological conditions in the environmentwhich harmfully effects the quality of life, including effects onother animals and plants.
Population: Group of organisms that belong to the samespecies and can interbreed freely.
Population growth rate: Natural increase in populationrepresented by the different between birth and death rates.
Predator: Organism that kills and eats another organism.
Prey: Organism that is killed and eaten by a predator.
Primary consumer: First organisms that eats the plants in thetropic level
Primary succession: Development of communities where noorganisms previously existed.
Principle of least effort: phenomenon when the population ofthe herbivores increases.
Producer (autotroph): Green plant or organism that, performsphotosynthesis.
Profundal zone: Deeper part of the lake water into whichsunlight does not penetrate.
Pyramid of energy: Representation of the organic content in eachtrophic level.
Radiation dose absorbed in the human or animal tissueequivalent to 100 grs/gram of tissue.
Reactor core: That which consists of fuel rods in a reactorvessel.
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Recycling: Processing of material into new products thatmay or may not resemble the original material.
Red tide: Phenomenon that occurs when the population of thedinoflagellates increases tremendously.
Relative humidity: Amount of moisture in a given quantity ofair divided by the amount the air could hold at that temperature.
Rem (or roentgen equivalent man): dose from any radiationthat produces biological effects in man equivalent to one rad orX ray.
Resilience: Ability of an organism to return to its normalstate after a disturbance.
Roentgen unit (R): Quantity of radiation (gamma or X ray)that will produce electrostatic unit of positive or negativeelectricity in 1cm3 of air at normal temperature and pressure.
Secondary consumer: Organism that belongs to the thirdtrophic level in a food chain.
Secondary succession: Sequential development of bioticcommunities occurring after the complete or partial destruction ofan existing community.
Sediment: Soil particles, sand, and other mineral matereroded from land and carried to surface waters.
Shale oil: Thick heavy oil formed when shale is heated.Slash-and-burn agriculture: Practice in farming in which the
forests are cleared by cutting and burning.Sludge: Solid organic material produced during sewage
treatment.Solar aqua cell: Waste water treatment, using solar heat.
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Solar collector: Derived from the sun and natural phenomenadriven by the sun.
Species: Kind of organism.Species diversity: Different kinds of plants and animals in a
community.Succession: Natural replacement of one community by another
community.Sustainable ethics: Set of views in which man and nature are
one and that the earth’s resources are limited.Taiga: Biome found south of North America, Asia, and
Europe and characterized by coniferous forests.Temperate deciduous forest: Biome characterized by
deciduous trees and abundant rainfall.Teratogen: Agent or chemical that causes birth defects.Top-down approach: Approach in solving environmental
problems which involves the creation of laws and regulationsthat will regulate behavior.
Toxic substance: Substance poisonous to human beings andanimals.
Transpiration: Evaporation of water from the leaves.Trophic level: Position occupied by lack of trees and low
temperature.Weathering: Process of breaking down rocks into small
particles.Wetland: Land area along freshwater and salt water.Xerophytes: Plant that grows in dry or arid conditions.
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METRIC UNIT CONVERSION TABLES
THE METRIC SYSTEMStandard metric Units Units AbbreviationsStandard unit of mass gram gStandard unit of length meter mStandard unit of volume liter l
CommonPrefix
Unit Examples
kilo 1,000 A kilogram is 1,000 grams.centi 0.01 A centimeter is 0.01 meter.milli 0.001 A milliliter is 0.001 liter.micro (µ) one-millionth A micrometer is 0.000001 (one-
millionth) of a meter.nano (n) one-billionth A nanogram is 10-9 (one-
billionth) of a gram.pico (p) one-trillionth A pictogram is 10-12 (one-
billionth) of a gram.
UNITS OF LENGTHUnit Abbreviations Equivalentmeter m Approximately 39 incentimeter cm 10-2mmillimeter mm 10-3m
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Unit Abbreviations Equivalentmicrometer µm 10-6mnanometer nm 10-9mangstrom Ǻ 10-10m
Length conversions1 in = 2.5 cm 1 mm = 0.039 in1 ft = 30 cm 1 cm = 0.39 in
1 yd = 0.9 cm 1 m = 39 in1 mi = 1.6 km 1 m = 1.094 yd
1 km = 0.6 mi
To convert Multiply by To obtaininches 2.54 centimeters
feet 30 centimeterscentimeters 0.39 inchesmillimeter 0.039 inches
UNITS OF VOLUMEUnit Abbreviations Equivalentliter l Approximately 1.06 qtmilliliter ml 10-3 (1ml = 1cm3 = 1cc)miccroliter µl 10-6 l
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Volume conversions Equivalent1 tsp = 5ml 1ml = 0.3fl oz1 tbsp = 15ml 1l = 2.1 pt1 fl oz = 30ml 1l = 1.06 qt1 cup = 0.24l 1l = 0.26 gal1 pt = 0.47l1 pt = 0.95 l1 gal = 3.8 l
To convert Multiply by To obtainfluid ounces 30 millilitersquarts 0.95 litersmilliliters 0.03 fluid ouncesliters 1.06 quarts
UNITS OF WEIGHTUnit Abbreviations Equivalentkilogram kg 103g (approximately 2.2 lb)gram g Approximately 0.035 ozmilligram mg 10-3 g
microgram µg 10-6 gnanogram ng 10-9 gpico gram pg 10-12 g
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Weight conversions1 oz = 28.3g 1g = 0.035 oz1 lb = 453.6g 1kg = 2.2 lb1 lb = 0.45kg
To convert Multiply by To obtainounces 28.3 gramspounds 453.6 gramspounces 0.45 kilogramsgrams 0.035 ounceskilograms 2.2 pounces
Temperature conversions Some equivalents
oC =9
5*)32( o F
oF =5
9*Co
+ 32
0oC = 32oF37oC = 98.6oF100oC = 212oF
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REFERENCES
1. Barrington, Ernest, and James William, EnvironmentalBiology, Wiley Inc., New York, U.S.A., 1980.
2. Chiras Daniel D., Environmental Science: A Framework forDecision Making, Benjamin/Cummings Publication Co.,California, U.S.A., 1988.
3. Committee for Global Biosphere Program, GlobalChange and Our Common Factor, National Academy Press,Washington, D.C., U.S.A., 1986.
4. Erickson Jon, Greenhouse Earth - Tomorrow’s DisasterToday. Blue Ridge Summit, Tab Books, P.A., U.S.A., 1990.
5. Nebel Bernard, Environmental Science. Englewood Cliffs,Prentice Hall, N.J., U.S.A., 1990.