EcologyEcology

PopulationPopulation

Includes all the members Includes all the members of a species found in a of a species found in a

given area.given area.Ex: sunfish in a pond Ex: sunfish in a pond

CommunityCommunity Includes all the populations Includes all the populations

in a given area.in a given area.

ExEx: all plants, animals, and : all plants, animals, and microorganisms make up a microorganisms make up a

pond communitypond community

EcosystemEcosystem

Includes all the members Includes all the members of the community plus the of the community plus the physical environment in physical environment in

which they live in.which they live in.

Ecological OrganizationEcological OrganizationPopulation ( or )

Community ( + + )

Ecosystem ( )

Biosphere ( )

(I) Ecosystem(I) Ecosystem

Is the structural and Is the structural and functional unit studied in functional unit studied in

Ecology.Ecology.

(A) Requirements for a Stable (A) Requirements for a Stable EcosystemEcosystem The ecosystem involves interactions The ecosystem involves interactions

between living and nonliving things. between living and nonliving things. Certain requirements must be met Certain requirements must be met for a stable ecosystem to exist:for a stable ecosystem to exist:

1.1. There must be a constant supply of There must be a constant supply of energy (sunlight for photosynthesis). energy (sunlight for photosynthesis).

2.2. There must be living organisms that There must be living organisms that can incorporate the energy into can incorporate the energy into organic compounds (food).organic compounds (food).

3.3. There must be a recycling of There must be a recycling of materials between organisms and materials between organisms and the environment.the environment.

(B) Abiotic Factors(B) Abiotic Factors Nonliving factors.Nonliving factors. The abiotic factors of an ecosystem include the The abiotic factors of an ecosystem include the

physical and chemical factors that affect the physical and chemical factors that affect the capacity of an organism to live and reproduce. capacity of an organism to live and reproduce. These factors are:These factors are:

1. Intensity and duration of light1. Intensity and duration of light

2. Temperature range2. Temperature range

3. Amount of moisture3. Amount of moisture

4. Type of substrate4. Type of substrate

5. Availability of inorganic substances and gases5. Availability of inorganic substances and gases

6. pH6. pH

(C) Biotic Factors(C) Biotic Factors Living factorsLiving factors These factors directly or indirectly These factors directly or indirectly

affect the environment.affect the environment. Thus, the organisms, their presence, Thus, the organisms, their presence,

parts, interaction, and wastes all act as parts, interaction, and wastes all act as biotic factors.biotic factors.

These interactions include:These interactions include: 1. Nutritional relationships1. Nutritional relationships 2. Symbiotic relationships2. Symbiotic relationships

(A) Requirements for a Stable (A) Requirements for a Stable EcosystemEcosystem The ecosystem involves interactions The ecosystem involves interactions

between living and nonliving things. between living and nonliving things. Certain requirements must be met Certain requirements must be met for a stable ecosystem to exist:for a stable ecosystem to exist:

1.1. There must be a constant supply of There must be a constant supply of energy (sunlight for photosynthesis). energy (sunlight for photosynthesis).

2.2. There must be living organisms that There must be living organisms that can incorporate the energy into can incorporate the energy into organic compounds (food).organic compounds (food).

3.3. There must be a recycling of There must be a recycling of materials between organisms and materials between organisms and the environment.the environment.

Limiting FactorsLimiting Factors Determines the types of organisms which Determines the types of organisms which

may exist in that environment.may exist in that environment. Examples are:Examples are:

1.1. A low temperature common to northern A low temperature common to northern latitudes determines in part what species latitudes determines in part what species of plants can exist in that area.of plants can exist in that area.

2.2. The amount of oxygen dissolved in a The amount of oxygen dissolved in a body of water will help determine which body of water will help determine which species of fish will exist there.species of fish will exist there.

1.Nutritional 1.Nutritional RelationshipsRelationships

Involves the transfer of nutrients from Involves the transfer of nutrients from one organism to another within an one organism to another within an ecosystem.ecosystem.

In terms of nutrition, organisms are In terms of nutrition, organisms are either autotrophs or heterotrophs.either autotrophs or heterotrophs.

Types of Types of HeterotrophsHeterotrophs

1.1. Saprophytes- include heterotrophic plants, fungi, Saprophytes- include heterotrophic plants, fungi, and bacteria which feed on dead organisms. and bacteria which feed on dead organisms.

Ex: mushrooms are saprophytes that feed off Ex: mushrooms are saprophytes that feed off dead plants.dead plants.

2. Herbivores- animals that feed on plants. 2. Herbivores- animals that feed on plants. Ex: deer Ex: deer 3. Carnivores- animals that consume other animals. 3. Carnivores- animals that consume other animals.

Two types: Two types: a) predator – which kills and a) predator – which kills and

consume consume their prey.their prey. b) scavenger- which feed on the b) scavenger- which feed on the

remains remains of animals they did not kill. of animals they did not kill. 4. Omnivores- animals that consume both plants 4. Omnivores- animals that consume both plants

and animals (humans). and animals (humans).

2. Symbiotic 2. Symbiotic RelationshipsRelationships Different organisms may live together in a close Different organisms may live together in a close

association.association. This is known as symbiosis.This is known as symbiosis. There are three types:There are three types:

1. Commensalism 2. Mutualism 3. Parasitism1. Commensalism 2. Mutualism 3. Parasitism KEY:KEY:

+ = benefits+ = benefits

- = harmed- = harmed

o = not affectedo = not affected

CommensalismCommensalism (+ , o)(+ , o)

In this relationship, one organism In this relationship, one organism benefits and the other is not affected.benefits and the other is not affected.

Ex: barnacles on a whaleEx: barnacles on a whale EX: Remora on a sharkEX: Remora on a shark

Mutualism Mutualism (+ , +)(+ , +) In this relationship both organisms In this relationship both organisms

benefit from each other.benefit from each other. Ex: protozoan living in the digestive Ex: protozoan living in the digestive

tract of termites.tract of termites. Wood eaten by termites is digested Wood eaten by termites is digested

by the protozoan. The nutrients by the protozoan. The nutrients released supply both organisms.released supply both organisms.

(Lichen)

ParasitismParasitism (+ , - )(+ , - )

In this relationship, the parasite In this relationship, the parasite benefits at the expense of the host.benefits at the expense of the host.

Ex: athlete’s foot fungus on Ex: athlete’s foot fungus on humanshumans

tapeworm and heartworm in dogs.tapeworm and heartworm in dogs.(Bloodworms Tapeworm Heartworms)

(II) (II) Energy Flow Energy Flow RelationshipsRelationships

For an ecosystem to be self-For an ecosystem to be self-sustaining, there must be a flow of sustaining, there must be a flow of energy between organisms.energy between organisms.

The pathway of energy flow through The pathway of energy flow through the living components of an the living components of an ecosystem are represented by ecosystem are represented by food food chainschains and and foodfood webs.webs.

(A) (A) Food ChainsFood Chains Green plants and other Green plants and other

photosynthetic organisms photosynthetic organisms are the organisms in an are the organisms in an ecosystem that can ecosystem that can convert radiant energy convert radiant energy from sunlight into food.from sunlight into food.

A A food chainfood chain involves the involves the transfer of energy from transfer of energy from green plants through a green plants through a series of organisms with series of organisms with repeated stages of eating repeated stages of eating and being eaten.and being eaten.

(A) (A) Food ChainsFood Chains

(B) (B) Food WebsFood Webs In a natural community, In a natural community,

most organisms eat more most organisms eat more than one species and may than one species and may be eaten, in turn, by more be eaten, in turn, by more than one species.than one species.

Thus, the various food Thus, the various food chains in a community are chains in a community are interconnected forming a interconnected forming a food web.food web.

There are three basic classes of There are three basic classes of organisms in a food web:organisms in a food web:

1.1. ProducersProducers- include green plants and other - include green plants and other photosynthetic organisms that synthesize the photosynthetic organisms that synthesize the organic nutrients that supply energy to other organic nutrients that supply energy to other members in the community.members in the community.

2.2. ConsumersConsumers- include all heterotrophic organisms. - include all heterotrophic organisms. Organisms that feed on green plants are Organisms that feed on green plants are primary primary consumersconsumers, or herbivores. , or herbivores. Secondary Secondary consumersconsumers, or carnivores, feed on other , or carnivores, feed on other consumers. consumers.

3.3. DecomposersDecomposers – are the organisms (saprophytes) – are the organisms (saprophytes) that break down wastes and dead organisms so that break down wastes and dead organisms so that chemical materials are returned to the that chemical materials are returned to the environment for use by other living organisms.environment for use by other living organisms.

(C) (C) Pyramid of EnergyPyramid of Energy The The greatest amount of energygreatest amount of energy in a community is in a community is

present in the organisms that make up the present in the organisms that make up the producer level.producer level.

Only a small portion of this energy is passed on to Only a small portion of this energy is passed on to primary consumers, and only a smaller portion is primary consumers, and only a smaller portion is passed on to secondary consumers.passed on to secondary consumers.

A A pyramid of energypyramid of energy can be used to illustrate the can be used to illustrate the loss of usable energy at each feeding level.loss of usable energy at each feeding level.

(III) (III) Cycle of MaterialsCycle of Materials In a self-sustaining ecosystem, various In a self-sustaining ecosystem, various

materials are recycled between organisms materials are recycled between organisms and the abiotic environment.and the abiotic environment.

The recycling process allows materials to The recycling process allows materials to be used over and over again.be used over and over again.

Three examples are:Three examples are:

1. Carbon-Hydrogen-Oxygen cycle1. Carbon-Hydrogen-Oxygen cycle

2. Water cycle2. Water cycle

3. Nitrogen cycle3. Nitrogen cycle

Carbon-Hydrogen-Oxygen Carbon-Hydrogen-Oxygen CycleCycle

Carbon, Carbon, hydrogen, and hydrogen, and oxygen are oxygen are recycled through recycled through the environment the environment by the processes by the processes of of respirationrespiration and and photosynthesis.photosynthesis.

Water CycleWater Cycle Here water moves between the earth’s surface and the Here water moves between the earth’s surface and the

atmosphere.atmosphere. EvaporationEvaporation- liquid water on earth’s surface changes to - liquid water on earth’s surface changes to

gas by the process of evaporation and enters the gas by the process of evaporation and enters the atmosphere in the form of atmosphere in the form of water vapor.water vapor.

CondensationCondensation- water vapor is returned to liquid state - water vapor is returned to liquid state and falls as precipitation.and falls as precipitation.

Some water vapor is added to the atmosphere by Some water vapor is added to the atmosphere by aerobic respirationaerobic respiration in plants and animals and by in plants and animals and by transpirationtranspiration in plants. in plants.

Water CycleWater Cycle

(IV) (IV) Ecosystem Ecosystem FormationFormation

Ecosystems tend to change over a long period Ecosystems tend to change over a long period of time until a stable ecosystem is formed.of time until a stable ecosystem is formed.

Both the living and nonliving parts of an Both the living and nonliving parts of an ecosystem change.ecosystem change.

(A) (A) Ecological SuccessionEcological Succession The replacement of one kind of community with The replacement of one kind of community with

another is called another is called ecological succession.ecological succession. The kind of stable ecosystem that develops in a The kind of stable ecosystem that develops in a

particular geographical area depends on climate.particular geographical area depends on climate. Pioneer organismsPioneer organisms- are the first plants to populate - are the first plants to populate

an area. Lichens and algae may be pioneer an area. Lichens and algae may be pioneer organisms on bare rock.organisms on bare rock.

Climax CommunitiesClimax Communities- Succession ends with the - Succession ends with the development of a climax community in which the development of a climax community in which the populations of plants and animals exist in balance populations of plants and animals exist in balance with each other and the environment.with each other and the environment.

(B) (B) CompetitionCompetition1.1. Different species living in the same Different species living in the same

environment, or environment, or habitathabitat, may require the , may require the same resources. When the resources are same resources. When the resources are limited, competition occurs among the limited, competition occurs among the species.species.

2.2. CompetitionCompetition- is the struggle between - is the struggle between different species for the same limited different species for the same limited resources. The more similar the needs of resources. The more similar the needs of the species, the more intense the the species, the more intense the competition.competition.

(B) (B) Competition (cont)Competition (cont)3. Each species occupies a 3. Each species occupies a nicheniche in the community. in the community.

A niche is the role the species plays, and A niche is the role the species plays, and includes the type of food it eats, where it lives, includes the type of food it eats, where it lives, where it reproduces, and its relationships with where it reproduces, and its relationships with other species. other species. Ex. catfish and the Asian carpEx. catfish and the Asian carp

4. When two different species compete for the same 4. When two different species compete for the same niche in a community, the weaker species is niche in a community, the weaker species is usually eliminated establishing one species per usually eliminated establishing one species per niche in a community.niche in a community.

(B) (B) CompetitionCompetition

NO,, I can’t NO,, I can’t compete with compete with

that!!!that!!!

Throw him

back!!

Throw him

back!!

Graphs showing competition between two species of Graphs showing competition between two species of ParameciumParamecium. Since . Since each population alone prospers (top two graphs), when they are in a each population alone prospers (top two graphs), when they are in a competition situation one species will win, the other will lose (bottom competition situation one species will win, the other will lose (bottom

graph).graph).

V.V. Biosphere Biosphere and and

HumansHumansAlmost two acres of trees disappear

every second.

Past and Past and PresentPresent

Humans, in exercising a Humans, in exercising a unique and powerful unique and powerful influence on the physical influence on the physical and living world, have and living world, have modified their modified their

environment.environment.

1. 1. Negative Negative aspectsaspects

Natural systems have been upset because Natural systems have been upset because humans have not realized that they not only humans have not realized that they not only influence other individuals, other species, and influence other individuals, other species, and the nonliving world, but are, in turn, influenced the nonliving world, but are, in turn, influenced by them.by them.

Although most ecosystems are capable of Although most ecosystems are capable of recovering form the impact of minor disruptions, recovering form the impact of minor disruptions, human activities have sometimes increased the human activities have sometimes increased the magnitude of such disruptions so as to bring magnitude of such disruptions so as to bring about a more lasting and less desirable change about a more lasting and less desirable change in the environment upon which all life depends.in the environment upon which all life depends.

Such disruptions will directly affect at least one Such disruptions will directly affect at least one of the components of an ecosystem and this, in of the components of an ecosystem and this, in turn, may affect the remaining components.turn, may affect the remaining components.

Examples of Negative Aspects:Examples of Negative Aspects:a) Human Population Growtha) Human Population Growthb) Human Activitiesb) Human Activities

--Over huntingOver hunting - Exploitation- Exploitation

- Importation of Organism- Importation of Organism - Poor Land Use Management- Poor Land Use Management - Technological - Technological OversightOversight

a) Human Population a) Human Population GrowthGrowth

The total population of The total population of humans has risen at a humans has risen at a rapid rate, partly because rapid rate, partly because of the removal of natural of the removal of natural checks on the population, checks on the population, such as disease.such as disease.

This continued increase in This continued increase in the human population has the human population has far exceeded the food-far exceeded the food-producing capacities of producing capacities of many ecosystems of the many ecosystems of the world.world.

a) Human Population a) Human Population GrowthGrowth

Population DensityPopulation Density

BiosphereBiosphere The portion of the earth in The portion of the earth in

which life exists.which life exists. The biosphere is composed The biosphere is composed

of many complex of many complex ecosystems that include ecosystems that include

water, soil, and air.water, soil, and air.

What is the ecological What is the ecological relevance of this relevance of this

cartoon?cartoon?

Global warmingGlobal warming

Global warmingGlobal warming Gases that trap heat in the Gases that trap heat in the

atmosphere are often called atmosphere are often called greenhouse gases. greenhouse gases.

Global Warming + Greenhouse Global Warming + Greenhouse Effect Effect

Some greenhouse gases such as Some greenhouse gases such as carbon dioxide occur naturally and are carbon dioxide occur naturally and are emitted to the atmosphere through emitted to the atmosphere through natural processes. natural processes. – Carbon DioxideCarbon Dioxide

Other are created and emitted solely Other are created and emitted solely through human activities. through human activities.

Greenhouse GasesGreenhouse Gases Carbon Dioxide (CO2)Carbon Dioxide (CO2): Carbon dioxide enters the atmosphere through the burning of fossil : Carbon dioxide enters the atmosphere through the burning of fossil

fuels (oil, natural gas, and coal), solid waste, trees and wood products, and also as a result of fuels (oil, natural gas, and coal), solid waste, trees and wood products, and also as a result of other chemical reactions (e.g., manufacture of cement). other chemical reactions (e.g., manufacture of cement).

– Carbon dioxide is also removed from the atmosphere as part of the biological carbon cycle. Carbon dioxide is also removed from the atmosphere as part of the biological carbon cycle.

Methane (CH4)Methane (CH4): Methane is emitted during the production and transport of coal, natural gas, : Methane is emitted during the production and transport of coal, natural gas, and oil. and oil.

– Methane emissions also result from livestock and other agricultural practices and by the decay of Methane emissions also result from livestock and other agricultural practices and by the decay of organic waste in municipal solid waste landfills. organic waste in municipal solid waste landfills.

Nitrous Oxide (N2O)Nitrous Oxide (N2O): Nitrous oxide is emitted during agricultural and industrial activities, as : Nitrous oxide is emitted during agricultural and industrial activities, as well as during combustion of fossil fuels and solid waste. well as during combustion of fossil fuels and solid waste.

Fluorinated GasesFluorinated Gases: Hydrofluorocarbons, fluorocarbons, and sulfur hexafluoride are : Hydrofluorocarbons, fluorocarbons, and sulfur hexafluoride are synthetic, powerful greenhouse gases that are emitted from a variety of industrial processes. synthetic, powerful greenhouse gases that are emitted from a variety of industrial processes.

– Fluorinated gases are sometimes used as substitutes for ozone-depleting substances Fluorinated gases are sometimes used as substitutes for ozone-depleting substances (i.e., CFCs, HCFCs, and halons). (i.e., CFCs, HCFCs, and halons).

– These gases are typically emitted in smaller quantities, but because they are potent greenhouse These gases are typically emitted in smaller quantities, but because they are potent greenhouse gases, they are sometimes referred to as High Global Warming Potential gases (“High GWP gases”). gases, they are sometimes referred to as High Global Warming Potential gases (“High GWP gases”).

http://epa.gov/climatechange/emissions/index.html#ggo

GLOBAL WARMING: Early Warning GLOBAL WARMING: Early Warning SignsSigns

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p:/

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Fingerprints and HarbingersHeat waves and periods of unusually warm weather

Sea level rise and coastal flooding

Glaciers melting

Arctic and Antarctic warming

Spreading disease

Earlier spring arrival

Plant and animal range shifts and population declines

Coral reef bleaching

Downpours, heavy snowfalls, and flooding

Droughts and fires

Examples of Negative Examples of Negative Aspects:Aspects:

a) Human Population Growtha) Human Population Growthb) Human Activitiesb) Human Activities

--Over huntingOver hunting - Exploitation- Exploitation

- Importation of Organism- Importation of Organism - Poor Land Use Management- Poor Land Use Management - Technological - Technological OversightOversight

b) Human Activitiesb) Human Activities Some human activities have led to the extinction Some human activities have led to the extinction

or endangerment of numerous species of plants or endangerment of numerous species of plants and animals as well as producing less favorable and animals as well as producing less favorable living conditions for many species, including living conditions for many species, including humans.humans.

Ex:Ex:– Over huntingOver hunting– Importation of OrganismsImportation of Organisms– Exploitation of WildlifeExploitation of Wildlife– Poor land use management, Poor land use management, ex. deforestationex. deforestation– Technical Oversights, Technical Oversights, ex. pollutionex. pollution

http://www.kodak.com/eknec/PageQuerier.jhtml?pq-path=38/492/2017/2033&pq-locale=en_US

Uncontrolled Uncontrolled hunting, trapping, hunting, trapping, and fishing still and fishing still occur in many parts occur in many parts of the world.of the world.

The extinction of the The extinction of the dodo bird and the dodo bird and the passenger pigeon passenger pigeon resulted from such resulted from such activities.activities.

1. 1. OverhuntingOverhunting

2. Importation of Organisms2. Importation of Organisms

                                  

               

Kudzu smothers native trees and shrubs.Kudzu smothers native trees and shrubs.

Purple Loosestrife Environmental Impacts Purple Loosestrife Environmental Impacts ofofreplaces native wetland communities replaces native wetland communities eliminates food and shelter for wildlife species eliminates food and shelter for wildlife species reduces biodiversity reduces biodiversity

2. Importation of Organisms2. Importation of Organisms Humans have Humans have

accidentally and/or accidentally and/or intentionally imported intentionally imported organisms to areas organisms to areas where they have no where they have no natural enemies natural enemies leading to the leading to the disruption of existing disruption of existing ecosystems.ecosystems.

Examples include the Examples include the Japanese beetle and Japanese beetle and the Gypsy moth.the Gypsy moth.

                                  

               

3. Exploitation3. Exploitation The exploitation of The exploitation of

wildlife for their wildlife for their products and pet trade products and pet trade has led to threatened has led to threatened populations and populations and ecosystem disruptions.ecosystem disruptions.

Examples include: the Examples include: the African elephant—ivory; African elephant—ivory; the Colombian parrot—the Colombian parrot—pet trade; Tropical rain pet trade; Tropical rain forest—plywood. forest—plywood.

3. Exploitation3. Exploitation The exploitation of wildlife for their products The exploitation of wildlife for their products

and pet trade has led to threatened and pet trade has led to threatened populations and ecosystem disruptions.populations and ecosystem disruptions.

Examples include: the African elephant—Examples include: the African elephant—ivory; the Colombian parrot—pet trade; ivory; the Colombian parrot—pet trade; Tropical rain forest—plywood. Tropical rain forest—plywood.

3. Exploitation3. Exploitation

44. Poor Land Use . Poor Land Use ManagementManagement

44. Poor Land Use . Poor Land Use ManagementManagement Increased urbanization/ suburbanization claims Increased urbanization/ suburbanization claims

increasing amounts of agricultural lands:increasing amounts of agricultural lands:– modifies watersheds, modifies watersheds, – disrupts natural habitats (including wetlands), disrupts natural habitats (including wetlands), – DeforestationDeforestation– and threatens the existence of wildlife species.and threatens the existence of wildlife species.

Poor land management practices have led to Poor land management practices have led to overcropping, overgrazing, and failure to use cover overcropping, overgrazing, and failure to use cover crops. This has resulted in the loss of valuable soil crops. This has resulted in the loss of valuable soil nutrients and topsoil.nutrients and topsoil.

44. Poor Land Use . Poor Land Use ManagementManagement

Deforestation: Deforestation: Clearing of tropical Clearing of tropical forests across the Earth.forests across the Earth.

*Most of the clearing is done for:*Most of the clearing is done for:

agricultural purposes, planting agricultural purposes, planting crops, grazing cattle, crops, grazing cattle, Commercial loggingCommercial logging

(In Bolivia, the average earnings (In Bolivia, the average earnings per person is $800.)per person is $800.)

DeforestationDeforestation

DeforestationDeforestation

5. Environmental Pollution due to 5. Environmental Pollution due to

Technological OversightTechnological Oversight

Have led to unplanned Have led to unplanned consequences which consequences which have contributed to have contributed to the pollution of the the pollution of the water, air, and land.water, air, and land.

Examples are:Examples are:

a) Water Pollutiona) Water Pollution

b) Air Pollutionb) Air Pollution

c) Biocide Usec) Biocide Use

d) Disposal Problemsd) Disposal Problems

Water PollutionWater Pollution Major water Major water

pollutants include: pollutants include: heat, sewage, and heat, sewage, and chemicals such as chemicals such as phosphates, heavy phosphates, heavy metals, and PCB’s.metals, and PCB’s.

**Oil spills**Oil spills

                                                      

                               

Water PollutionWater Pollution

Air PollutionAir Pollution*Major air pollutants include: *Major air pollutants include:

carbon monoxide, carbon monoxide, hydrocarbons, hydrocarbons,

and particulates. and particulates. Nitrogen oxides Nitrogen oxides and sulfur dioxide and sulfur dioxide combine with water vapor combine with water vapor

creating acid rain problems.creating acid rain problems.

Air PollutionAir Pollution

Biocide UseBiocide Use The use of some The use of some

biocides (such as biocides (such as pesticides) without a pesticides) without a complete complete assessment of their assessment of their environmental environmental impact has impact has contaminated the contaminated the soil, atmosphere, soil, atmosphere, water supply, and water supply, and has disrupted foodhas disrupted food webs.webs.

Ex: DDTEx: DDThttp://www.kodak.com/eknec/PageQuerier.jhtml?pq-path=38/492/2017/2033&pq-locale=en_UShttp://www.kodak.com/eknec/PageQuerier.jhtml?pq-path=38/492/2017/2033&pq-locale=en_US

DDT a Banned InsecticideDDT a Banned Insecticide** 1939 discovered the effectiveness of DDT** 1939 discovered the effectiveness of DDT

**DDT seemed to be the ideal insecticide it is cheap and of **DDT seemed to be the ideal insecticide it is cheap and of relatively low toxicity to mammals. relatively low toxicity to mammals.

**Extensive use of DDT began to appear in the late 1940s..**Extensive use of DDT began to appear in the late 1940s..

****Linked to the RAPID decline of Raptors (birds of prey) due Linked to the RAPID decline of Raptors (birds of prey) due to the thinning of calcium layers of eggs shells.to the thinning of calcium layers of eggs shells.

**The use of **The use of DDT was banned in the United States in 1973DDT was banned in the United States in 1973, , although it is still in use in some other parts of the world. although it is still in use in some other parts of the world.

** The buildup of DDT in natural waters is a reversible ** The buildup of DDT in natural waters is a reversible process: the EPA reported a 90% reduction of DDT in Lake process: the EPA reported a 90% reduction of DDT in Lake Michigan fish by 1978 as a result of the ban. Michigan fish by 1978 as a result of the ban.

DDT a Banned InsecticideDDT a Banned Insecticide

http://birdcam.kodak.com/cgi-bin/asCgi.pl?node=1&app=birdcam&laf=playground

Land Recourses Land Recourses and Conservationand Conservation Clean Air Acts 1963Clean Air Acts 1963 Wilderness Act 1964, National PreservesWilderness Act 1964, National Preserves Clean Water Act 1972Clean Water Act 1972 Safe Drinking Water ActSafe Drinking Water Act Endangered Species Act, 1973Endangered Species Act, 1973 Farm Act 1985, protection of wetlandsFarm Act 1985, protection of wetlands California Desert Protection Act 1994California Desert Protection Act 1994

Disposal ProblemsDisposal Problems The affluent lifestyle The affluent lifestyle

of humans currently of humans currently requires increasing requires increasing supplies of products supplies of products and energy, the and energy, the production of which production of which produces produces considerable wastes: considerable wastes: solid, chemical, and solid, chemical, and nuclear.nuclear.

       

        

Eutrification Eutrification

2. Positive Aspects2. Positive Aspects Through increased awareness Through increased awareness

of ecological interactions, of ecological interactions, humans have attempted to humans have attempted to prevent continued disruptions prevent continued disruptions of the environment and to of the environment and to counteract the results of many counteract the results of many of our negative practices.of our negative practices.

Examples of Positive Examples of Positive AspectsAspects

1.1. Population ControlPopulation Control2.2. Conservation of ResourcesConservation of Resources3.3. Pollution ControlPollution Control4.4. Species PreservationSpecies Preservation5.5. Biological ControlBiological Control6.6. LawsLaws

Population Population ControlControl

Methods of controlling Methods of controlling the human reproductive the human reproductive rate have been, and rate have been, and continue to be continue to be developed.developed.

Conservation of Conservation of ResourcesResources

Soil cover plantings Soil cover plantings (reforestation and (reforestation and covercropping) serve covercropping) serve as erosion controls.as erosion controls.

Water and energy Water and energy conserving measures conserving measures are currently being are currently being implemented.implemented.

The economic The economic significance of significance of recycling is now recycling is now being realized.being realized.

Pollution ControlPollution Control

Attempts are being made Attempts are being made to control air and water to control air and water pollution by laws and by pollution by laws and by the development of new the development of new techniques of sanitation.techniques of sanitation.

Species PreservationSpecies Preservation Some efforts to sustain Some efforts to sustain

endangered species have endangered species have included habitat protection included habitat protection (wildlife refuges and national (wildlife refuges and national parks) and wildlife management parks) and wildlife management (game lawa and fisheries).(game lawa and fisheries).

Animals which were once Animals which were once endangered are now endangered are now successfully reproducing and successfully reproducing and increasing their numbers.increasing their numbers.

Examples of endangered animals Examples of endangered animals which are responding to which are responding to conservation efforts and conservation efforts and beginning to make a comeback beginning to make a comeback are the bald eagle and the are the bald eagle and the peregrine falcon.peregrine falcon.

Do NowDo Now

What Cause the What Cause the ALMOST ALMOST extinction of extinction of these 2 birds?these 2 birds?

Species PreservationSpecies PreservationU.S. and Canada, Japan, Mexico and the former Soviet U.S. and Canada, Japan, Mexico and the former Soviet

Union Union Establishment of a Federal prohibition, unless Establishment of a Federal prohibition, unless

permitted by regulations, to:permitted by regulations, to:– MIGRATORY BIRD TREATY ACTMIGRATORY BIRD TREATY ACT – Endangered Species ActEndangered Species Act

http://ipl.unm.edu/cwl/fedbook/mbta.html

Species PreservationSpecies PreservationU.S. and Canada, Japan, Mexico and the former Soviet U.S. and Canada, Japan, Mexico and the former Soviet

Union Union Establishment of a Federal prohibition, unless Establishment of a Federal prohibition, unless

permitted by regulations, to:permitted by regulations, to:– MIGRATORY BIRD TREATY ACTMIGRATORY BIRD TREATY ACT – Endangered Species ActEndangered Species Act

http://ipl.unm.edu/cwl/fedbook/mbta.html

Biological ControlBiological Control Biological control of insect pests Biological control of insect pests

continues to be encouraged.continues to be encouraged. This method is less likely to affect This method is less likely to affect

those species which are beneficial to those species which are beneficial to humans, disrupt food webs, and humans, disrupt food webs, and contaminate the land.contaminate the land.

Examples include the use of sex Examples include the use of sex hormones and natural parasites.hormones and natural parasites.

Land Recourses Land Recourses and Conservationand Conservation

There are laws which regulate and guide the There are laws which regulate and guide the use of natural habitats.use of natural habitats.

Example: State Environmental Quality Review Example: State Environmental Quality Review ActAct ( (SEQR)SEQR)

A New York State law designed to provide the A New York State law designed to provide the opportunity for citizen review and comment of opportunity for citizen review and comment of the environmental impact of any proposed the environmental impact of any proposed development that has been determined to development that has been determined to have significant effect on the environment.have significant effect on the environment.

Land Recourses Land Recourses and Conservationand Conservation Clean Air Acts 1963Clean Air Acts 1963 Wilderness Act 1964, National PreservesWilderness Act 1964, National Preserves Clean Water Act 1972Clean Water Act 1972 Safe Drinking Water ActSafe Drinking Water Act Endangered Species Act, 1973Endangered Species Act, 1973 Farm Act 1985, protection of wetlandsFarm Act 1985, protection of wetlands California Desert Protection Act 1994California Desert Protection Act 1994