environmental production engineering

8/2/2019 Environmental Production Engineering

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0.SUSTAINABLE DEVELOPMENTDefinition of Sustainable Development:

The conservation/supporting of the essential qualities of life (such as clean air and water, productive

soil, natural areas with abundant wild-life, freedom from hazardous waste) which are not being

depleted or degraded but are maintained and renewed so that they will be available in the future in

at least the same abundance as they are now.

I. Features of the contemporary industrial development (19602000)

The world today produces and consumes more than ever before. The yearly growth of theworld economy has been a little above 4 %. Services and manufactured goods amounting to $30trillion (being 5 in 1950 and forecasted to be 130 in 2050.

Timber production increase3 times (paper production6 times)

Catch of fish5 times

Production of grain3 times

Extraction of fossil fuels4 times

This increase is related to the demographic explosion the doubling of the Earths

population for the recent 40 years and the increased duration of life (from 47 to 64 years).

One quarter of humanity has now joined the consumer classadopting the diets,

transportation systems, and lifestyles once limited to the rich nations of Europe, North America, and

Japan. But amongst this wealth, great poverty persists, with nearly three billion peopletwo out of

every fivebarely surviving on less than $2 a day. Private consumption expendituresthe amount

spent on goods and services at the household levelhave increased fourfold since 1960, topping

more than $20 trillion in 2000. The 12 percent of the world's people living in North America and

Western Europe account for 60 percent of this consumption, while the one-third living in South

Asia and sub-Saharan Africa account for only 3.2 percent.

The world economy can no further expand in this manner of industrial revolution and

exploit its natural resources without finally self-destructing. If Earths biosphere is perceived as a

single living organism, then such a growth for the growth itself resembles the ideology of the

cancer cellso called Cancer on the Earth.

A. Carrying Capacity and Destruction of the Ecosystems

Our progress is based on the availability of easily obtainable natural resources (fossil fuels

and raw materials). More customers demands for goods and services stimulate the introduction of

new technologies and further increase of production. At the same time human damage to theenvironment ultimately will limit the worlds carrying capacity.

When the carrying capacity of a natural system is exceeded, the consumption may only

increase t the expense of using up the basis of the resources and thus the elements of the ecosystem

are being destroyed.

The carrying capacity of the soil is related to the production it may yield. When we

misuse the soil, we reach a stage of exhaustion of its fertility and degradation of the surface

humus layer, which had been formed for millions of years by the prevailing soil-forming

processes of accumulation of organic substances. Plants exist and feed on the thin surface

layer of the soil, at the same time preventing its erosion.


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Water consumption is tripled (70% for irrigation purposes) and results in reduction of

the flowrate of the sources or completely exhausting some of them. The latter is observed in

grain-growing Earths regions with artificial irrigation (agriculture at improper conditions

Kazakhstan, Syria, Saudi Arabia).

During the last century the Earth has lost 50% of its forests. The net production of

oxygen has declined; the balance evaporation/precipitation has been broken. Unique forest

ecosystems have been destroyed.

Despite the claims that the oceans will in the future ensure worlds food, the catch of

fish is at its limiting capacity (approx. 90 million tons yearly) and cannot be raised in the

future. In recent years worlds fishing regions have been operated to (or even beyond) their

capacity. The artificial breeding of fish is related to ensuring its feeding and increase of the

price of the production.

The increased emission ofCO2, based on fossil fuels results in an altered climate and

thinned ozone layer. The seasons have shifted and changed; there is an increased probability

for storms, floods; the weather is unpredictable in the long run; hot and cold waves succeedeach other.

The existing equilibrium in the natural ecosystems has been destroyed, and "a

rapidly spreading invasion of exotic plants and animals is destroying our nation's biological

diversity". 1 100 out of 10 000 species of birds are in danger of or completely extinct; 25% of

the 4 400 species of mammals as well as 1/3 of all fresh-water and sea fish are in danger of

extinction. Forests and valleys are no longer densely inhabited with the populations that had

lived there for centuries. The loss of species weakens life itself and destroys the

accumulated and reserved genetic information. The vacancies in the ecosystems are occupied

by improper and alien to them exotic species, which further change and eventually destroythem.

B. Pollution

The Air in large regions is polluted with substances of industrial origin; pollutants are

transferred at large distances; acid rains are observed over extensive areas; the atmosphere

over big cities is a mixture of poisonous substances; children suffer chronic asthma and lungs

variations. Overheating of the surface and an abrupt greenhouse effect are present. Sunrays

become increasingly dangerous due to the rising amount of ultraviolet radiation.

The natural cycle ofwater is destroyed and the larger rivers are polluted by numerous

industries (Western Europe, China, India, etc.). Underground waters are polluted by thepoisonous chemicals used in industry and intensive agriculture. A large portion of the

population do not have access to good quality drinkable water; springs dry-up and rivers

flowrate is reduced.

Arable lands are degraded, salted or with reduced fertility. Pastures are destroyed or

have eroded due to improper agriculture. The proportions of humus and organic substances

have dropped in the soil. A significant portion of the arable land is misused for building,

industrial or infrastructure purposes.

C. The Demographic Explosion (Overpopulation)

At present the worlds population is over 6 billion (1 in 1800, 3 in 1960 and 6 in 1999), witha yearly increase of about 77 million and doubling of the population every 40 years. Every second 5


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people are born and 3 die, leading to an increase rate of 2 per second. All forecasts for 2050 say the

population would be over 9 billion (a minimum of 7.9 and a maximum of 10.9 billion people). The

rate of population increase in the developing countries is 2.5-3% (4% for Africa). In 2050 60 % of

the population will be in Asia, while that of Africa will have doubled.

The population increase is related to shortage (or increase in the prices) of food supplies.

The protein production is in a process of transition to entirely artificial growing of some species,

this being liable to infections and epidemics. The use of fertilizers on exhausted and polluted soils is

up to the sensible limit; the agricultural production is rich in chemicals and pesticides. Rural

economy is based on classical varieties of monocrop agriculture, suited to the old methods of soil

cultivation. Genetic engineering is making its way into agriculture, thus introducing a new element

of risk.

The increase in the prices of food supplies results in an increase in the number of starving

and under-fed people, particularly in developing countries. Nations now tend to group themselves

by social level (rich/poor), rather than by ideological or racial features. The tension between these

levels builds up and leads to large-scale displays of hatred (local fanatism, terrorism, etc.) by the

poorer or a tendency of isolation in the wealthy nations (visas, immigration control, etc.). Meeting

basic human needs, slowing the unprecedented growth in human numbers, and protecting vital

natural resources such as fresh water, forests, and fisheries are all prerequisites to healthy, stable

societies. Working together to solve global social and environmental problems, we can also reduce

the conditions that too often lead people and nations to resort to violent solutions. The human kind

is divided and has different conceptions of the future of the world and the values of life. The

governments promise further growth (even in the developed democracies). They postpone

unpopular decisions for the following generation when the choice will be limited and the problems

harder to resolve. No one observes the changes in the environment or when the carrying capacitiesare reached/exceeded; only events of catastrophic destruction of the natural systems provoke a

reaction.

Sustainability, Carrying Capacity, and OverconsumptionWorld population would not be a problem if there were unlimited land, unlimited water, unlimited resources.

Unfortunately, with overpopulation, there is the problem of sharing the same sized pie with smaller and smallerportions. People in developed countries who have been accustomed to a better quality of life are reluctant to give it up.In many cases, more efficient use of resources has come along hand-in-hand with improved quality of life. But there arestill problems of overconsumption, exploitation, the short-sighted search for an ever-higher quality of life, and the greedof companies and individuals in cutting corners resulting in pollution and reckless use of raw materials. Less-developedcountries that, in the past, had smaller populations such that slash-and-burn agriculture had less impact, cities had fewer

vehicles to send pollution into the air, and industries were not as attracted by cheap labor and thus polluted rivers andthe air less.

This is a difficult subject. Should people have less children or should people use less resources, pollute less?Or both? Should one problem have priority over the other? The world population has doubled in the last forty years.Who has contributed the most to overconsumption and pollution? The more developed nations with a relatively stablepopulation growth, but who use 5-50 times the resources of the poor, or the less developed nations whose populationswill double again in 30 years, who will run out of food and water first, and whose pollution due to agricultural burning,coal burning, lack of emission controls, mis-use of pesticides, and toxic waste from under-regulated industries, will onlyworsen with the increase of population? And then there is the question of ownership and distribution of resources, dothe rich exploit the poor, and to what extent? As I said, this is a difficult subject.

There is a delicate balance here: we want the poor countries to improve their economic situation and toimprove the family's quality of life. This has been know to lower the birth rate. But we want the rich countries toconsume less, perhaps lower the quality of life. We need to balance the quality of life between the rich and the poor, at

the same time, hoping to balance the family size between the rich and the poor.


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Key Emerging Environmental Threats - from the UNEP - United Nations Environmental Program, Dec8, 1998 - Freshwater supply and quality both surface and groundwater, assessment of watersheds; Risk and thereat tohuman health due to collapse of ecosytem health; Pollution of the lower atmosphere due to combustion of fossil fuelsand biomass burning; Land/marine interaction (e.g. eutrophication); Environmental flashpoints/security, transboundaryissues; Nuclear waste issues; Long-term and inter-annual climate change issues; Habitat loss and forest fragmentation;Endangered species and link with food security and economic impacts; Sanitation and waste due to urbanization;Crosscutting issues of urbanization; i.e., related to megacities; Quality of life (technologies to monitor, say, human

health impacts from pollution in urban areas); Chemical and toxic substances; Critical environmental zones; e.g.,identification and early warning of problems like Aral Sea.

Common global environmental issues are: Global climate Change; Stratospheric ozone depletion; Loss ofbiodiversity; Freshwater degredation; Desertification and land degradation; Deforestation and the unsustainable use offorests; Marine environment and resource degradation; Persistent organic polluntants.

Staggaring statistics from a March 2000 report entitled World Resources 2000-20001, by the UnitedNations Development Program: Half of the world's wetlands were lost last century. Logging and conversion haveshrunk the world's forests by as much as half. Some 9 percent of the world's tree species are at risk of extinction;tropical deforestation may exceed 130,000 square kilometers per year. Fishing fleets are 40 percent larger than theocean can sustain. Nearly 70 percent of the world's major marine fish stocks are overfished or are being fished at theirbiological limit. Soil degradation has affected two-thirds of the world's agricultural lands in the last 50 years. Some 30percent of the world's original forests have been converted to agriculture. Since 1980, the global economy has tripled in

size and population has grown by 30 percent to 6 billion people. Dams, diversions or canals fragment almost 60 percentof the world's largest rivers. Twenty percent of the world's freshwater fish are extinct, threatened or endangered.

RICHER, FATTER, AND NOT MUCH HAPPIERAround 1.7 billion people worldwidemore than a quarter of humanityhave entered the "consumer class,"

adopting the diets, transportation systems, and lifestyles that were limited to the rich nations of Europe, North America,and Japan during most of the last century. In China alone, 240 million people have joined the ranks of consumersanumber that will soon surpass that in the United States.

"Rising consumption has helped meet basic needs and create jobs," says Worldwatch Institute PresidentChristopher Flavin. "But as we enter a new century, this unprecedented consumer appetite is undermining the naturalsystems we all depend on, and making it even harder for the world's poor to meet their basic needs."

"Higher levels of obesity and personal debt, chronic time shortages, and a degraded environment are all signsthat excessive consumption is diminishing the quality of life for many people. The challenge now is to mobilize

governments, businesses, and citizens to shift their focus away from the unrestrained accumulation of goods and towardfinding ways to ensure a better life for all."

Private consumption expendituresthe amount spent on goods and services at the household levelhaveincreased fourfold since 1960, topping more than $20 trillion in 2000, reports State of the World 2004. The 12 percentof the world's people living in North America and Western Europe account for 60 percent of this consumption, whilethe one-third living in South Asia and sub-Saharan Africa account for only 3.2 percent.

Consumption among the world's wealthy elites, and increasingly among the middle class, has in recent decadesgone beyond satiating needs or fulfilling dreams to become an end in its own right, note State of the World 2004 projectdirectors Lisa Mastny and Brian Halweil. At the same time, consumption is rising rapidly in the developing world, asglobalization has introduced millions of people to consumer goods, while providing the technology and capital toproduce and disseminate them.

"Nearly half of all global consumers now live in the developing world," says Mastny. "While the averageChinese or Indian consumes much less than the average North American or European, China and India alone now boast

a combined consumer class larger than that in all of Western Europe."Consumption is not in itself a bad thing, adds Halweil. "The almost three billion people worldwide who barely

survive on less than $2 per day will need to ramp up their consumption in order to satisfy basic needs for food, cleanwater, and sanitation. And in China, the rush to meet surging consumer demand is stimulating the economy, creating

jobs, and attracting foreign investment."There is little evidence that the consumption locomotive is brakingparticularly in the United States, where

most people are amply supplied with the goods and services needed to lead a good life.In the United States today, there are more private vehicles on the road than people licensed to drive them, the

Worldwatch report points out. The average size of refrigerators in U.S. households increased by 10 percent between1972 and 2001, and the number per home rose as well. New houses in the U.S. were 38 percent bigger in 2000 than in1975, despite having fewer people in each household on average. As a result of these consumption patterns, the UnitedStates, with just 4.5 percent of the world's population, releases 25 percent of global carbon dioxide emissions.

Yet increased consumption has not brought Americans happiness. About a third of Americans report being

"very happy," the same share as in 1957, when Americans were only half as wealthy. Americans are also some of themost overworked people in the industrial world, putting in the equivalent of nine more weeks on the job each year thanthe average European.


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This rising consumption in the U.S., other rich nations, and many developing ones is more than the planet canbear, reports State of the World 2004. Forests, wetlands, and other natural places are shrinking to make way for peopleand their homes, farms, malls, and factories. Despite the existence of alternative sources, more than 90 percent of paperstill comes from treeseating up about one fifth of the total wood harvest worldwide. An estimated 75 percent ofglobal fish stocks are now fished at or beyond their sustainable limit. And even though technology allows for greaterfuel efficiency than ever before, cars and other forms of transportation account for nearly 30 percent of world energyuse and 95 percent of global oil consumption.

At the same time, however, growing dissatisfaction with current consumption trends has led consumeradvocates, economists, policymakers, and environmentalists to develop creative options for meeting people's needswhile dampening the environmental and social costs of mass consumption.

State of the World 2004 points to a range of opportunities that are already available to governments,businesses, and consumers to curb and redirect consumption:

Ecological tax reform. By shifting taxes so that manufacturers have to pay for the harm they do to theenvironment, and by introducing production standards and other regulatory tools, governments can help minimizenegative impacts on natural resources.

Take-back Laws. Now being adopted by a growing number of governments around the world, these lawsrequire companies to "take back" products at the end of their useful lives, and typically ban the landfilling andincineration of products.

Durability. Industries can take shared responsibility for their ecological impacts by finding ways to reduce theamount of raw material needed to create products and by making goods more durable and easy to repair and upgrade.

Personal responsibility. Changes in consumption practices will also require millions of individual decisionsthat start at the grassrootsabout everything from our use of energy and water to our consumption of food.

"It would be foolish to underestimate the challenge of checking the consumption juggernaut," concludesFlavin. "But as the costs of unbridled appetites grow, the need for innovative responses becomes clearer. In the longrun, meeting basic human needs, improving human health, and supporting a natural world that can sustain us willrequire that we control consumption, rather than allow consumption to control us."

GROWING DISPARITIES:

LUXUR: In 2002, 1.12 billion householdsabout three quarters of the world's peopleowned at least onetelevision set. Some 41 million passenger vehicles rolled of the world's assembly lines in 2002, five times as many as in1950. The global passenger car fleet now exceeds 531 million, growing by about 11 million vehicles annually.Consumers across the globe now spend an estimated $35 billion a year on bottled water.

NECESSITY: In 1999, some 2.8 billion peopletwo in every five humans on the planetlived on less than

$2 a day. In 2000, one in five people in the developing world1.1 billion totaldid not have reasonable access tosafe drinking water. 2.4 billion people worldwidetwo out of every fivelive without basic sanitation. Providingadequate food, clean water, and basic education for the world's poorest could all be achieved for less than people spendannually on makeup, ice cream, and pet food.

II. The Concept of Sustainable Development

The most difficult question to be answered is whether further growth in either population or

economic activity is tolerable.

On one hand many environmental scientists warn that human activities are overwhelming the

basic life-support systems of the biosphere. They call for a steady state economic system that willminimize our impact on the environment.

On the other hand economic growth is a way to bring the underdeveloped nations up to a higher

standard of living. Economic Growth is also necessary to provide funds to clean up the

environmental damage caused by earlier, more primitive technologies and misguided resource uses.

An intermediate position between no growth vs. unlimited growth is sustainable development,

based on the use of renewable resources in harmony with the ecologic systems.

III. Establishing a new economy

The way a sustainable economy should function, as well as its major principles are known. This

is a system, which:

does not exceed the carrying capacity of the natural resources


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relies on renewable energy sources

is supplied with raw materials from recycling and multiple use

is not involved with the release of dangerous substances and waste

copies the structure from the natural ecosystems

A. Principles for Achieving Sustainable Development

1) A demographic transition to a stable world population through reaching equilibrium

between low birth rates and low death rates. This must involve an effective birth control

(family planning, education, changes in traditions and culture). Otherwise changes will

occur not only in the number, but also in the demographic profile and the minority

proportions of the population in the individual countries. 33 countries have achieved

stabilizing their population (Western Europe 0-1%, Japan, USA about 1%, the former

socialist countriesnegative population growth).

2) Transition to renewable energy sources as soon as these become sufficiently

sophisticated and affordably cheaper. New technologies are to be introduced, reducing

energy and raw material consumption (cellular phones, information storage and transferon/through electronic media), rejection of heavy infrastructure, transport avoiding fossil

fuels (bicycles, electric and other non-polluting cars, airships replacing airplanes, etc).

3) Utilizing of recycled raw materials copying the model of the natural systems. The

waste materials of a production are used by other productions until the full

transformation of the former into final products. All household and industrial machines

and appliances must be recyclable too.

4) Introduction of industrial technologies and raw materials, which do not release

pollutants. Rejection of the end of pipe emission processing related technologies.

Introduction of waste-free productions and avoidance of technologies associated withgeneration of hazardous waste at any stage.

5) Changes in the structure of agriculture. Replacement of the monocrop agriculture and

the use of chemicals; introduction of new varieties of crops; transition to lower food

levels. Transition to biological forms of protection; maintaining the amount of organic

substance in the arable soil. Reduction of the number of concentrated and artificially bred

animals. Transition to local, typical for the particular region crops. Genetic modification,

or any other new agricultural technology must be done with great care and caution,

applying the Precautionary Principle to Genetically Modified Crops.

6) Conservation of the natural arals and ecosystems over sufficiently large areas, ensuring

their reproduction and recovery. Creation of a system of protected regions existing

without external interference (humans, infrastructure, external species, etc.).

Discontinuation of the loss of animal and plant species. Recovery and recultivation of

devastated terrains and regions.

7) Developing and enforcing political and governmental resolutions. Implementation of a

system of benefits and taxes encouraging sustainable development in all fields of

industry; fines or full recovery of damages done to the environment or yield of raw

materials exceeding the carrying capacity.


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Enviromentalism for the 21st

Century - Patrick Moore

All social movements evolve from an earlier period of polarization and confrontation during which a minority strugglesto convince society that its cause it is true and just, eventually followed by a time of reconciliation if a majority of thepopulation accepts the values of the new movement. For the environmental movement this transition began to occur inthe mid-1980s. The term sustainable development was adopted to describe the challenge of taking the newenvironmental values we had popularized, and incorporating them into the traditional social and economic values that

have always governed public policy and our daily behavior. We cannot simply switch to basing all our actions on purelyenvironmental values. Every day 6 billion people wake up with real needs for food, energy and materials. The challengefor sustainability is to provide for those needs in ways that reduce negative impact on the environment. But any changesmade must also be socially acceptable and technically and economically feasible. It is not always easy to balanceenvironmental, social, and economic priorities. Compromise and co-operation with the involvement of government,industry, academia and the environmental movement is required to achieve sustainability. It is this effort to findconsensus among competing interests that has occupied my time for the past 15 years.Not all my former colleagues saw things that way. They rejected consensus politics and sustainable development infavor of continued confrontation and ever-increasing extremism. They ushered in an era of zero tolerance and left-wingpolitics. Some of the features of this environmental extremism are:Environmental extremists are anti-human. Humans are characterized as a cancer on the Earth. To quote eco-extremistHerb Hammond, "of all the components of the ecosystem, humans are the only ones we know to be completelyoptional". Isn't that a lovely thought?

They are anti-science and technology. All large machines are seen as inherently destructive and unnatural. Science isinvoked to justify positions that have nothing to do with science. Unfounded opinion is accepted over demonstratedfact.Environmental extremists are anti-trade, not just free trade but anti-trade in general. In the name of bioregionalism theywould bring in an age of ultra-nationalist xenophobia. The original "Whole Earth" vision of one world family is lost in ahysterical campaign against globalization and free trade.They are anti-business. All large corporations are depicted as inherently driven by greed and corruption. Profits aredefinitely not politically correct. The liberal democratic, market-based model is rejected even though no viablealternative is proposed to provide for the material needs of 6 billion people. As expressed by the Native Forest Network,"it is necessary to adopt a global phase out strategy of consumer based industrial capitalism." I think they meancivilization.And they are just plain anti-civilization. In the final analysis, eco- extremists project a naive vision of returning to thesupposedly utopian existence in the garden of Eden, conveniently forgetting that in the old days people lived to an

average age of 35, and there were no dentists. In their Brave New World there will be no more chemicals, no moreairplanes, and certainly no more polyester suits.What are the main features off a rational environmental policy for the 21st century? Some points to consider are asfollows:

Wherever possible, we should move towards an economy that is based on renewable energy and materialresources. Sustainability is not synonymous with renewability but it is strongly linked to it. Where we do use non-renewable resources they should be used wisely and recycled whenever practical.

We should learn to manage our population voluntarily. The UN Conference on Population, held in Cairo in1994, concluded that the most effective way to manage population growth is the education and empowerment ofwomen. This leaves no place for patriarchy, religious fundamentalism, or dictatorships.

We should develop a more globally unified analysis off the relationships among land use, energy and resourceconsumption, forests and biodiversity, and population. Policies that have global implications must not be logicallyinconsistent one with the other.

We should learn to be better gardeners at both local and global scales. With 6 or 8 billion mouths to feed thiswill require more intensive agricultural production including the use of fertilizer, synthetic pesticides, andbiotechnology. It is a simple fact of arithmetic that the less land we need to grow our food the more is available forforest and wilderness.

Urban sprawl must be brought under control. We have allowed the automobile to determine urban form bydefault. 300,000 hectares of forest are lost in the United States every year, all of it due to 200 cities spreading out overthe land. Denser, more livable, cities must be designed if population continues to grow.

Deforestation in the tropics must eventually be stabilized or reversed. This can be accomplished by the transferof intensive agricultural practices, the establishment of fast-growing, sustainable fuel-wood plantations, and themanagement of population growth.

Chapter 1 - The Challenge for Johannesburg: Creating a More Secure World -Gary Gardner

Ten years after the 1992 Earth Summit, an assessment of the state of the world indicates that neither environment nordevelopment has fared well. While awareness of environmental issues has increased and remarkable progress can be
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cited in niches such as wind power and organic farming, nearly all global environmental indicators continue to beheaded in the wrong direction.Many social issues advanced slowly, with some of the gains offset by other setbacks. But the decade saw decreases indeaths for infectious diseases such as pneumonia and diarrhea, a sixfold increase in deaths from HIV/AIDS more thancancelled all of these advances. People in wealthy countries were living longer than ever, but some 14,000-30,000people continued to die each day from water-borne diseases.World Summit priorities: Building on the small gains of the 1990s and accelerating the movement toward a sustainable

world. Goals may range from ending the progressive shrinking of natural forest area, to achieving universal completionof primary school.Chapter 2 - Moving the Climate Change Agenda Forward -Seth Dunn and Christopher FlavinGoing into Johannesburg, scientists have stronger evidence that most of the world's warming of the past 50 years isattributable to human activities. But with the Bush Administration in the U.S. and European ministers once againreadying to square off on global warming, one may wonder whether Johannesburg in 2002 will be simply a repeat ofRio in 1992, when the first Bush administration refused to embrace mandatory commitments to counter climate change.Despite the slow start, the world has not stood still in the decade since the signature and ratification of the U.N.Framework Convention on Climate Change. The science, economics, business, and politics of the climate issue have allevolved in ways that may help to move the agenda forward. A growing number of multinationals, such as BP, DuPont,and Nike, have taken on commitments to reduce greenhouse gas emissions, and recent government studies in the U.S.,Europe, and Japan suggest a significant potential for low- to no-cost emissions cuts via the use of cleaner and moreenergy-efficient technologies.World Summit priorities: Bringing the Kyoto Protocol into force before the Summit is of critical symbolic importance;setting forth a blueprint for post-Johannesburg climate negotiations, emphasizing the need to reengage the UnitedStates; considering a second period of emissions cuts; and expanding the group of countries with emissions targets willalso further negotiations.Chapter 3 - Farming in the Public Interest -Brian HalweilDelegates at the 1992 Earth Summit envisioned farming systems that ensure an adequate and accessible food supply,provide stable livelihoods for rural communities, and help build ecological health. Today, however, even as our farmshave become more technologically sophisticated, they have become ecologically dysfunctional and socially destructive.In addition to contributing to some of our most threatening environmental problems-from global warming to the spreadof toxic chemicals-farm families are suffering. Roughly 100 million families-about 500 million people-lack ownershiprights to the land they cultivate.Fortunately, farmers and agricultural scientists in many parts of the world are beginning to learn how to restructure theway we produce food to better serve the multiple functions outlined at Rio, focusing less on purchased chemicals andtechnological fixes and more on taking advantage of the ecological processes occurring in the field.World Summit priorities: Shifting agricultural subsidies to support ecological farming practices; taxing pesticides,synthetic fertilizers, and factory farms; and assuring women equal rights and support in agriculture.Chapter 4 - Reducing our Toxic Burden -Anne McGinnThe 2001 signing of the Stockholm Convention on Persistent Organic Pollutants (POPs), which holds countriesaccountable for the regulation of 10 of the most hazardous intentionally produced pollutants, was one of the keyenvironmental achievements in the decade since the 1992 Earth Summit in Rio.The impact of toxic chemicals is already widespread-the average person today carries levels of lead that are 500-1,000times higher than our pre-industrial ancestors, and worldwide some 300-500 million tons of hazardous wastes aregenerated each year. Post-Stockholm, the global community faces a dual challenge: reforming an enormous sector ofthe industrial economy while also taking action on the toxic materials that exist now either as waste or as commoditiescirculating in the economy.World Summit priorities: Phasing out leaded gasoline; ratifying the three major global toxics treaties (Stockholm, Basel,and Rotterdam); taxing emissions of metals and toxic byproducts from industrial sources; eliminating persistentcompounds in dissipative uses, such as farming and cleaning; and funding research on safer materials andenvironmentally sound methods of waste disposal.Chapter 5 - Redirecting International Tourism -Lisa MastnyToday's travelers are trading in over-commercialized mass tourism for new cultural and nature-based experiences, manyof which are found in the developing world. One in every five international tourists now travels from an industrialcountry to a developing one, up from one in 13 in the mid 1970s. In the last decade alone, international tourism arrivalsworldwide have increased by nearly 40 percent.This tourism boom has generated much-needed revenue and employment at many destinations. But it has also brought ahost of environmental, social, and cultural problems. On average, half of the tourism revenue that enters the developingworld "leaks" back out, going to foreign owned companies or to pay for imported goods and labor. Many participants inthe tourism industry-including businesses, governments, local communities, and tourists-are beginning to take importantsteps to redirect tourism, from implementing regulations to boosting tourist awareness.
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World Summit Priorities: Formulating comprehensive, multi-stakeholder plans for tourism development; balancinglarge tourism investments with smaller-scale, locally-run tourism initiatives; and developing stronger regulations andpolicies to protect destinations against unsustainable tourism developments.Chapter 6 - Rethinking Population, Improving Lives - Bob EngelmanRapid growth of the world's human population is one of the trends underlying persistent poverty and the degradation ofthe natural environment. Although the global rate of population growth peaked at 2.1 percent a year in the 1960s andhas declined to under 1.3 percent today, the planet still adds about 77 million people each year, the equivalent of 10

New York Cities.Ultimately, reversing this trend depends on building and maintaining the political will to support family planning andrelated health services that allow couples and individuals to make their own decisions about both the timing ofpregnancy and broader reproductive health matters. As the largest generation of young people in human history-1.7billion people aged 10-24-reaches reproductive age, recasting population policy as a venture in social development andgreater gender equality will be essential.World Summit priorities: Funding universal access to reproductive health care; closing the gender gap in education;increasing female participation in all levels of politics; and enacting and enforcing strong laws to protect women fromgender-based violence.Chapter 7 - Breaking the Link Between Resources and Repression -Michael RennerIn several countries around the developing world, abundant natural resources are at the root of the matter-eithertriggering violent conflict or financing its continuation. In fact, about a quarter of the 49 wars and armed conflictswaged during 2000 had a strong resource dimension. And many of them are taking place in areas of great

environmental value.In some cases, groups initiate violence to gain and maintain control over lucrative resources. In others, the pillaging ofoil, minerals, metals, gemstones, or timber allows wars to continue that were initially caused by other factors, such asunresolved grievances or ideological struggles, as seen in Sierra Leone (diamonds) and Afghanistan (emeralds, lapislazuli, heroin). Conflict has also erupted in countries such as Columbia (oil) and Indonesia (timber, natural gas), wherethe benefits accrue to a small elite while the social and environmental burdens are borne by local communities.World Summit priorities: Developing stronger global certification systems for diamonds, timber, and other resources tomake it easier to screen out those produced and traded illicitly in conflict areas. And securing better compliance withU.N. sanctions against illicit resource trafficking by improving the capacity of the United Nations, regional andinternational organizations, and governments to monitor and enforce embargoes.Chapter 8 - Reshaping Global Governance -Hilary FrenchThe Rio Earth Summit resulted in several major developments in international governance, including new treaties onclimate change and biological diversity, the creation of the U.N. Commission on Sustainable Development, and sectionsof Agenda 21 dedicated to broader questions of institutional reform, financing, and public participation. But a few yearslater, the World Trade Organization was created with a starkly different vision of the future global economy.Ten years after Rio, there are more than 500 environmental treaties and agreements, but few of them contain specifictargets and timetables and most are weak on provisions for monitoring and enforcement. At the same time, the U.NEnvironment Programme and other key ecological initiatives are strapped for cash, and overall aid spending hasdeclined substantially. Despite this lackluster track record, at the World Summit in Johannesburg nations will haveanother chance to shift the course of the global economy and the institutions that underpin it away from destruction andtoward ecological and social integrity.World Summit priorities: Partnering with NGOs, businesses, governments, and international institutions are key toensuring a successful outcome at Johannesburg; promoting greater cooperation and coherence between the UnitedNations, the World Bank, the International Monetary Fund, and the World Trade Organization; and respecting the goalsand provisions of international environmental, human rights, and labor treaties and standards.
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1.ECOLOGICAL SYSTEMS:BASIC CONCEPTS,STRUCTURE ANDFUNCTION

A. Definitions

Ecology: is the study of the environment and the interactions that occur among theorganisms and between organisms and the environment. The word ecosystem is derived from theGreek oikos for home, coupled with the concept of a system. At the global level, these lifesupport systems include the: - transfer of energy from sunlight to plant and its distributionthroughout food web; - storage, release and distribution of carbon - an essential building block ofall live formsby forests, oceans and atmosphere; - cycling of nutrientsnitrogen and phosphorus,between air, water, soil and living organisms; - water cycle which purifies and distributes Earthsfresh water; - oxygen cycle through which plants and animals exchange carbon dioxide and oxygen.

Biosphere: biosphere consists of the layer of living things interacting with air (atmosphere),

water (hydrosphere), and earth surface (lithosphere). All ecosystems on earth (including humanecosystems) are interconnected and interdependent and make up one single entire entity, thebiosphere.

Species: specific kind(s) of plants, animals, and microbes that possess the ability tointerbreed. Members of the same species will breed to reproduce their kind, while members fromdifferent species can breed only with their kind to do so. Subdivisions of species are referred to asdifferent races or varieties. Our planet is literally crawling, not to mention swimming and flying,with life. Scoop up a handful of soil from your backyard, and you could have thousands of speciesright there in your palmand many of these might well be unknown to science. Today, scientistsestimate that there are between 15 and 100 million species and almost 1 million of these are insects.(The larger figure account for the unexplored diversity of microscopic live forms).

Population: consists of all the members of the same species that live in the same area at thesame time; represent the number of species either as a whole or in a given area. It represents thebirth rate/death rate relationships of the given species as well.

Biological community: All population of living organisms that live and interact in the samearea.

Ecosystem: a grouping of various species of plants, animals and microbes interacting witheach other and with their environment or distinctive plant community of grouping of particularplants which support a particular array of animals and microbes. The interrelationships betweenthem are such that the entire grouping may perpetuate itself, perhaps indefinitely. Each groupingalong with its environment is an ecosystem. An ecosystem is defined as place having uniquephysical features, encompassing air, water, and land, and habitats supporting plant and animal life.

They are the functional units of the biosphere, as sells are functional units of living organisms.Biomes: very large terrestrial ecosystems (forests, prairies, etc.). Each biome generally

contains a number of smaller but related ecosystems within it. All ecosystems are interconnectedand interdependent so that they are not isolated.

The landscape division of different ecosystems is rather arbitrary, since they seldom haveboundaries. One ecosystem (biome) blends into the next through a transitional region that containsmany of the species and characteristics of the 2 adjacent systems. This may create uniqueenvironments that support distinctive plants and animals as well as those that are common to theadjoining ecosystems, thus the transitional regions may also be considered as ecosystems.

Biodiversity

Many people believe that biodiversity should be preserved not just because it is valuable to us in some way, but simplybecause it exists. People who hold this opinion believe that each species should be respected and protected because it is


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the product of many thousands or millions of years of evolution, and we have no right to interrupt the evolutionaryprocess.They also argue that we have no right to destroy something we did not create and that future generations deserve anatural world that is rich and varied. Because we have the power to destroy species and ecosystems, they say, humanshave a moral obligation to be careful stewards of the Earth.Biodiversity the live diversity on the planet Earth and could be expressed through the:-genetic variability within a species (e.g. the differences in body size, the colours etc.);

-diversity of populations of a speciesin both the number of individuals within a local group and the distribution oftheir geographic range (e.g. the size and presence of the populations);-diversity of species within a natural community (abundance of species in the ecosystems);- wide array of natural communities and ecosystems throughout the world (e.g. tropical rain forests, tallgrass prairies,etc.).These cycles shape the climate, providing us with a survivable temperature range and an atmosphere in which we canbreathe. Along with these cycles, ecosystems also provide more subtle, but equally essential services. For example theydecompose and biodegrade our waste and generate and renew the soils, that produce our food crops. Within ecosystems,species play particular roles that enhance our survival and quality of life. Some species provide particular beneficialservices to humans. Wetlands filter toxins, provide clean water and control floods. Estuaries act as seafood nurseriesand forested watershed supply fresh water and control erosion. These services are provide by the combined actions andrelationships of many species within an ecosystem. A loss of biodiversity, measured as a reduction in the number ofspecies or populations, diminished the rate and capacity of the cycles that produce ecosystem services. When

biodiversity declines within a habitat or geographic area, greater fluctuations in ecosystem cycles tend to occur and theeco system as a whole tends to become less stable. Instability increases a systems vulnerability to extreme conditions

and catastrophic events, such as floods and droughts, and also reduces the sustainability and productivity of the region.In addition such natural disasters are enormously costly to human life and economies. Conversely, as biodiversityincreases in an ecosystem so too does the stability and resilience of that ecosystem.Our children will inherit the planet with whatever biodiversity we pass on to them. The decisions we make asindividuals and as a society today will determine the diversity of genes, species, and ecosystems that remain in thefuture.Many of these decisions are not easy, especially when they involve balancing the immediate needs, rights, and desiresof individuals and communities with the measures necessary to protect nature for the long term. Understanding whatbiodiversity is and how different people value it is an essential first step to designing strategies for long-termconservation.

B. Biotic Structure of Ecosystems

Biota: all organisms in one ecosystem (plants, animals and microorganisms) in theecosystem are referred to as the biota (bio = life). Biological (biotic) factors are the organisms andtheir products (secretions, wastes and remains) that are components of the environment.

Biotic Structure: refers to the way categories of organisms fit together. Despite theirdiversity, all ecosystems have a similar biotic structure. That is, they all have the same basiccategories of organisms that interact together in the same ways. The major categories of organismsare producers, consumers, detritus feeders and decomposers.

Producers: mainly green plants, which carry on photosynthesis. Photosynthesis is theprocess in which green plants use light energy to convert CO 2 and water into sugar (C6H12O6) and

release O2 as a byproduct. Plants can manufacture all additional complex molecules (organiccomplex chemicals such as protein, fats and carbohydrates which make up tissues of plants andanimals) for their bodies from sugar and some mineral nutrients (from soil and water). Themolecule that is used to capture light energy is chlorophyll, which has a green pigment. Henceplants that can carry on photosynthesis are easily identified by their green color. Plants are notnecessary in green in color as some other pigments can change additionally the color of the plant.They support the rest of the organisms in the ecosystem. But we should not forget that not all plantsare producers.

Consumers: Organisms that consume organic material as a source of energy and nutrients.They are divided into various subgroups according to their food source as primary, secondary andso on. Primary consumers feed directly on the producers. Secondary consumers feed on primary

consumers. Tertiary consumers feed on secondary consumers and so on. Certain organisms canoccupy more than one position on the consumer scale (humans).


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Herbivores: primary consumers that eat only plant material.Carnivores: secondary or higher order of consumers that eat animals only.Omnivores: feed on both plants and animals.Parasites: defined as organisms that become intimately associated with their prey and feed

on it over an extended period of time, typically without killing it, but causing to it some harm.Scavengers: animals that feed on dead plant and animal bodies.Detritus feeders: organisms specialized to feed on detritus (dead plant and animal material)

and break it down in the process back into inorganic material. As with regular consumers we canidentify primary, secondary etc. detritus feeders (earth worms wood beetles, ants, termites etc.). Therotting or decomposition in the ecosystems is a result of the feeding activity of decomposers.

Decomposers: a subcategory of detritus feeders, which includes fungi & bacteria. Fungiinclude moulds, mushrooms, coralfungi. Divided as such because of their distinctiveness

- they have reproductive cells called spores and are present everywhere;- they feed upon organic materials if suitable conditions of temperature and moisture prevent;- they are primary detritus feeders as a subcategory from them.

Soil

The top layer of decomposed rock and organic matter, which usually contains: air, moisture and nutrients, and cantherefore support life. Soil type includes sand, clay, loam (a sand-clay) mixture and peat (which contains a largeproportion of decaying plant matter) and is a dynamic interaction between mineral partials, dead plant and animalwastes and detritus feeders and decomposers. Humus is the residue of undigested organic matter, which remains afterthe bulk of detritus, has been consumed. Bacteria, fungi, protozoas, insects, earthworms and other burrowing animalsreduce the detritus to nondigestible humus compounds. Humus is not permanent despite its resistance to digestion andits subject to decomposition at a rate of 20 to 50% volume per year. Without periodic addition of ample detritus humusis gradually decompose and process is called mineralization. Degraded soil can be remediate but it requires severaldecades or even hundred of years.

Feeding Relationships: relationships in which one species benefit while others are harmed toa greater or lesser extent. They include various food chains that form in their turn food webs.

Food chain: a pathway where one organism is eaten by a second, which is eaten by a third

and so on. Food chains seldom exist as isolated entities. All food chains are interconnected, thusforming a complex food web (a complex pattern of incorporated food chains).

Trophic Levels: trophic literally means feeding, hence trophic levels are feeding levels.All producers belong to the first trophic level, primary consumers to the second, organisms feedingon them to the third, etc. The total combined weight or biomass at each trophic level is 90-99% lessthan on the preceding one, thus forming a biomass pyramid. The reason of that is that much of thefood that is consumed is broken down for energy at each trophic level and relatively little isconverted into body mass of the consumer, consequently a large biomass cannot be supported at theend of a long food chain. All food chains must start with a producer.

Non-Feeding relationships: these are usually mutually supportive relationships. Can be:Mutualism: mutual benefit to both species (flowers and insects - pollination, coral and fish -

cleaning, etc.).Symbiosis: refers to any intimate relationship between two organisms (birds and trees,

predator - prey, etc.). Hence it includes parasitism as well as mutualism. Mutually supportiverelationships that go far beyond close kinds of relationships. They can be found even in thepredator-prey relationships (killing the prey, which is usually weak or diseased, helps keeping thepopulation healthy).

Competitive Relationships: occur when species (mostly plants) compete for common water,nutrients, light and space. It is quite common for both plants and animals. The competition has asignificant effect in determining the character of the ecosystem. However, animals in naturalecosystems seldom (if ever) are in direct competition since they are adapted to feeding on different

things.


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C. Abiotic Structure

Abiotic Structure: the nonliving, chemical and physical factors of the environment, such aslight, temperature, water, wind, chemical nutrients, acidity, saltiness and fire. Organisms areaffected simultaneously by all of these factors. The degree to which each factor is present or absentaffects the ability of the organism to survive. Different species are affected differently. That is so,

because they thrive under different conditions.Optimum: the point that supports the maximum growth of the species. Actually it may be arange (rather than point) consisting of several degrees, thus there is rather an optimal range.

Range of Tolerance: the entire range from minimum to maximum, which supports anygrowth.

Limits of Tolerance: the points at the high and low ends of the range of tolerance.Zones of Stress: situated between the optimal range and the limits of tolerance, there is

increasing stress or zones of stress, and so until the limit of survival tolerance is precluded. Eachspecies has an optimum, zones of stress and limits of tolerance with respect to every environmentalfactor.

Law of Limiting Factors: Only one factor being outside the optimal range will cause stress

and limit the organism. Such a factor is termed as a limiting one. Population density of species willbe greatest where all conditions are optimal.

Temperature and Precipitation: Water and temperature are the main reasons preventing theecosystems from taking over each other. For example water is the main factor responsible for theseparation of biomes into forests, grasslands and deserts. Temperature also plays a major role indemarcating major ecosystems. However, the effect of temperature is largely superimposed on thatof rainfall. Temperature also exerts some influence as it effects on the evaporation of water. Waterevaporates faster at higher temperature.

D. Organization of Elements in living and Non-Living Systems

Organization of Elements in Living & Non-Living Systems: There are about 20 elements

that constitute all living organisms. The most significant of which are: C, H, O, P, S, N. The mostimportant chemical feature that distinguish the living from the non-living things is the molecule.These carbon-based molecules, which comprise the tissue of all living things, are called organic.Organic molecule is every molecule that has any C-C and/or C-H bonds.

Organic Compounds: they do not exist in the air, in water or minerals to any appreciableextent except where they have been introduced as a result (from pollution or natural processes) ofthe activities of living organisms.

Inorganic Compounds: consist of all other compounds that do not possess C-C and/or C-Hbonds. The life processes of growth and reproduction of producers can be seen as taking C, H, O, P,S and N from simple inorganic compounds in the environment & rebonding them into complexorganic molecules. Consumers do the same thing staring with molecules present in food. Theprocesses of burning and decay involve a breakdown of organic molecules and their rearrangementinto simple inorganic molecules.

Law of Conservation of Matter: In chemical reactions atoms are never created, destroyed orchanged, they are only rearranged to form different molecules and compounds.

Energy: energy is divided into 2 categories: kinetic (energy of action or motion) & potential(energy in storage).

First Law of Thermodynamics: energy is neither created nor destroyed, but it may beconverted from one form to another.

Second Law of Thermodynamics: In any energy conversion you will end up with lessuseable energy than you start with because of the inevitable loss of heat that occurs during the

process.


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Energy and Organic Matter: All organic molecules contain more than the atoms of C, H, O,P, S and N but also potential energy. This is evident by the simple fact that they burn. The heat andlight of the flame is their potential energy released as kinetic energy.

Matter and Energy Changes in Organisms:Producers producers take C and O atoms from carbon dioxide (absorbed from the air or

water solution for aquatic plants) and H from water molecules and with the help of the

photosynthesis construct the molecules of glucose and release O. They are also only 15% efficientin converting light energy to stored potential chemical energy.

Consumersthey exhibit a considerable output of kinetic energy; the process through whichthey break organic molecules to release the stored potential energy is called cell respiration(opposite of photosynthesis).

Detritus Feeders & Decomposers detritus possesses high potential energy and nutrientsand is a good food source for the organisms that can digest them. The major portion of it is brokendown through cell respiration to release energy for their life functions while another portion is usedas raw materials for the actual growth of tissues.


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2.ECOSYSTEMS BALANCE AND CHANGE

A. Principles of Ecosystems Function

First Basic Principle of Ecosystems Function: Resources are supplied and wastes disposed

of by recycling all elements. Nutrient Cycling: Organic material and oxygen produced byphotosynthetic are what consumers need for eating and breathing. The waste from consumers, CO2and minerals excreted in the urine, are the needed nutrients by the plant producers.

Carbon cycle: Through photosynthesis, C atoms are incorporated into glucose & then intothe other organic molecules that make up the plant tissues. Through food chains they move into andbecome part of the tissues of all other organisms (consumers). When the organic molecules are usedin cell respiration the C atoms are released back to the environment as CO 2, thus completing onecycle and of course ready to start another.

Phosphorus cycle: P exists in rock and soil minerals, as ion phosphate, which dissolves inwater, but doesn't enter air. Plants absorb it from soil or water solutions and incorporate it intoorganic compounds. Then through food chains it is passed to all other organisms. If the compoundscontaining it are oxidized in cellular respiration, it is released back in the environment through urineor waste, where it may be absorbed by the plants to start another cycle.

Nitrogen cycle: it has got both a gas and a mineral phase. The main source for N is theatmosphere. However, plants can not utilize it directly from there. For that purpose it must be in amineral form as ammonium or a nitrate. Fortunately, a number of bacteria and certain blue-greenalgae can convert N gas to the ammonium form, a process called nitrogen fixation. As organiccompounds containing N are broken down in cell respiration, N is excreted, generally in theammonium form. Additional bacteria may convert it to nitrate form, but any plant may reabsorb itin either form.

B. Energy Flow and Decreasing of Biomass

Energy flow: In the ecosystems, energy flow is in full harmony with the laws ofthermodynamics. It is converted from light (by photosynthesis) in stored chemical energy and thisenergy is reconverted to various forms though food chains. At each step, a portion of the chemicalenergy (food) is broken down to release its potential energy and, as this energy is used to performthe organisms functions or work, it is gradually converted to and lost as heat. Thus we observe a

flow of energy though ecosystems entering as light, performing work, and exiting as heat.Second Basic Principle of Ecosystems Function:Ecosystems run on solar energy, which is

exceedingly abundant, nonpolluting, relatively constant and ever lasting of which they utilize only a

small portion.Decreasing biomass at higher trophic levels: As each consumer, detritus feeder or

decomposer breaking down only a fraction of its food to release energy, the total biomass at highertrophic levels is also reduces by that fraction (for example 0.1).

Third Principle of Ecosystems Function:Large biomasses can not be supported at the endof long food chains. Increasing population means moving closer on the food chain to the source of

production.

C. Population Balance & Dynamics

The most important concepts of population dynamics is that different strategies regulatedensity, depending on the niche occupies by species in the ecosystem and its stability. The suddenlygrowth or decline of population are called population explosion and crash. Ecosystem balancedepends on the population within a community staying constant (how birth rate is balanced with

death rate) using different mechanisms that regulate population size, distribution and growth rate.


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Such an equilibrium in which the maximum numbers of individuals of any species can besuported on a long term basis by a particular ecosystem is the carrying capacity of the environment.

Biotic Potential and Environmental Resistance.Biotic Potentialthat is all the factors that contribute to a species increasing its numbers or

the maximum reproductive rate. Factors that lend to increasing a population include:

- reproductive rate- ability to migrate- ability to adapt and invade other habitats- defense mechanisms and resistance to adverse conditionsEvery species has sufficient biotic potential to increase rapidly its population if all

environmental factors are favorable population explosion. In the ecosystems there are limits togrowth depending on its carrying capacity. When a population exceeds the carrying capacity iscalled overshoot or explosion which followed by population crash (Maltusian growth). Populationmay go through repeated oscillating cycles of exponential growth and catastrophic crashes.

Environmental Resistance the combination of abiotic plus biotic factors which limit thepopulation growth such as pH, temperature, amount of water, lack of food, predators, diseases and

so on, is termed environmental resistance. Regulatory factors of environmental resistance aredensity dependent (as population density increases, environmental resistance become more intense)or independent (abiotic components of the ecosystem). Conversely if population density decreases,environmental resistance is generally mitigated allowing the population to recover.

Principle of Population Change: a change in population of a species is the result of thedynamic balance between biotic potential and the environmental resistance it faces.

Maltusian "Strategies" Organisms with such patterns often tend to occupy low trophic levelsin their ecosystems or to be pioneers in succession. They move quickly into disturbed environment,grow rapidly, mature early and produce many offspring. They usually are able to do little care fortheir offspring or cannot protect them from predation. Normally they ensure some offspring survival

to adulthood using sheer numbers and dispersal mechanisms. If the internal factors that normallycontrol their population are inoperative they tend rapidly to overshoot the carrying capacity of theenvironment and then dieback catastrophically. Theoretical unlimited growth is presented by socalled "J" curve.

Logistic "Strategies" They tend to occupy higher trophic levels in their ecosystems andreproduce at slower rate. These organisms are usually larger, live longer, mature slowly, producefewer offspring in each generation and have fewer natural predators. These species provides morecare and protection for its offspring. Theoretical growth an stabilization with environmentalresistance is presented by so called "S" curve

Critical Numbers: if a population is pushed below a certain critical number necessary tosupport the group, biotic potential fails and extinction is virtually assured.

Mechanisms of Balance Factors that regulate population growth could be: - intrinsic(between organisms in the same species) and extrinsic (imposed from outside the population); -biotic (caused by living organisms) and abiotic (caused by non-living components of theenvironment); - density dependant (in a higher proportion of the population is affected as its densityincreases) and density independent (weather and climatic conditions, water availability and drought,fires, geological hazards etc.). Species diversity provides ecosystem stability. .

By Predator-Prey Relationship as population increases it runs into increasedenvironmental resistance in the form of limited food and shelter and increased predation. As aresult, the population begins to fall. As it falls environmental resistance is lowered and thepopulation increases again, repeating the cycle. Predatorpray balance is not automatic, they have

been developed over many millions of years.By Host-Parasitic Relationshipparasitic organisms act in the same way as large predators.As the population density of the host organism increases, parasites have little trouble finding new


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hosts and infection rates increase causing population decrease. Conversely if host populationdensity decreases there is a reduction in infection levels and the population is recovered again.

Competition among Plants and Plant-Herbivore Balance plants species compete even onapparently uniform areas for light, nutrients, and water. A factor that plays an important role inmaintaining this diversity in a plant community is herbivore. Herbivory that is plants being fedupon by any of numerous kinds of herbivores. The relationship between plants and herbivores isvery similar to the one between predator and prey. (UpDown).

Territorialitya behavioral adaptation that tends to keep a population within resource limitsas a territory. Prevention of breeding without territory. Defend as a pack not as an individ.

D. Ecosystems Change

Primary Succession the process of initial invasion and then progression from oneecosystem to another (gradual succession from moss, through small plants and finally trees).

Secondary Successionthe reestablishment of an ecosystem that was originally present onit currently abandoned area (from abandoned agricultural field back to broadleaf forest)

Climax Communitywhen an ecosystem reaches a point when all present species continue

to reproduce in proportion and no further change occurs.Degree of Imbalance and Rate of Change.Succession slow, gradual change, such that the degree of imbalance at any time is not

great. There exists orderly and gradual displacement of some species by other, such that a diverseecosystem is maintained throughout.

Ecological Upsetsudden changes that lead to a population explosion of one species at theexpense of most other species in the system (introduction of foreign species) the opposite tosuccession.

Collapse of Ecosystemwhen changes are so drastic that almost nothing survives. Usuallylater the collapse of the ecosystem is followed by succession from species that can tolerate the newcondition.

Natural changes are generally gradual, leading to succession. On the other hand humaninduced changes are often sudden and/or drastic, leading to upsets or collapse.

Human Ecosystems: Agriculture is essentially a process of taking particular species out ofthe wild clearing space and providing other condition to grow them preferentially. The truth is thatyet 90% of the worlds food is derived from only 15 species of plants. In total, humans use only

about 150 species of plants for food, out of 80 000 potentially edible plants. Humans began tocreate their own distinctive system apart from natural ecosystems. Such systems are unable toovercome the usual limiting factors, but some of them (nutrient supply, water, predator, parasites,and competition) could be overcome by:

- producing abundant food - mono agricultural systems replaced original ecosystems;

- introducing new more productive exotic species - destroying natural biota;- creating water reservoirs and irrigation - wet land extinction, soil destruction, salt desert;- overcoming predators - polluting soil with using chemicals for killing them;- constructing their own habitats - making different ecosystems equal demolishing wild diversity;- overcoming competition - creating non-competitive and extremely unstable species/systems.

E. Adaptation & Change or Extinction of Ecosystems

Genetic Variation.Sexual Reproduction the genetic makeup of virtually all organisms consists of two

complete sets of genes. As cells divide in the process of body growth, each new cell receives anexact copy of both sets of genes. However, a different cell division process occurs in the formation

of ova (eggs) and sperm cells. Egg and sperm cells end up with just one set of genes. This set is arandom assortment of the genes of the corresponding parent, so that each egg and sperm cell will


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differ from the other egg and sperm cells in terms of the particular members of the gene pair of thecorresponding parent they have got.

Mutationsadditional genetic variation may come into the picture through mutations. Theyare random accidental changes in the DNA, and they may involve any gene or genes. They canoccur spontaneously (with no apparent cause).

Change through Selective Breeding gene pools may be changed in desired ways throughselective breeding. Breeders first envision the characteristic that they would like to achieve intogiven species; for example a dog with short, squat legs. Then, examining the existing population ofdogs, they select individuals that show the desired traits a little more then others, and use them asthe parents for the next generation. The offspring tend to be as the parents, but some express theparticular traits more then the parents. Those individuals that show the trait the most are selected asthe parents for another generation. This process called the selective breeding is repeated over andover again until gradually the desired traits are fully developed.

Change through Natural Selectionin nature every generation of every species is subjectedto an intense selection for survival and reproduction. Individuals that manage to survive andreproduce pass their alleles on to the next generation, while thealleles of those that do not survive

are eliminated from the pool. Thus the gene pool for every species is constantly undergoing aprocess of natural selection, in which new alleles that provide a trait which aids survival andreproduction will become increasingly widespread in the population. Simultaneously, genes that areless effective in promoting survival are gradually weeded out of the population as individualscarrying them fail to survive or reproduce. It is hardly surprising then, that virtually all traits of allorganisms serve in one way or another to support the survival and reproduction of that species.

Evolutionary Succession - Through natural selection a species may become increasinglywell adapted to coping with predators, parasites, climatic conditions, and other abiotic and bioticfactors present. As any biotic or abiotic factor is changed, each species that is ill adapted to the newsituation faces three possibilities.

Migration. Part of the population may be able to migrate and find an environment where the

conditions are still optimal, and thus continue to exist in the new location.Adaptation. Depend of two factors: - amount of genetic diversity in the genepool of the

species; - degree of change. The gene pool of the species may contain sufficient variation so thatsome individuals will tolerate the new conditions, survive and reproduce. Natural selection oversucceeding generations will lead to population that is increasingly well adapted to the newcondition.

Extinction. If none of the individuals in the population can escape the new condition bymigration and the new conditions are outside the limits of tolerance for all individuals, thenextinction of the population and the gene pool it represents is the inevitable result. Indeed, the fossilrecord is replete with now extinct species. Dinosaurs are only the best known.

Survival of the species depends on maintaining its genetic diversity and on minimizing

changes.


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3.AIR RESOURCES:ATMOSPHERE,CLIMATE &WEATHER

A. Basic Atmosphere properties

The atmosphere is a mechanical mixture of gases, not a chemical compound. Four gases

account for 99.98% of the air by volume - nitrogen - 78.08%, oxygen - 20.94%, argon - 0.93% andcarbon dioxide - 0.032%. These gases are mixed in remarkably constant proportion up to about 80km. In addition the atmosphere is made up of a mixture of gases with numerous aerosols (solid andliquid suspended particles) plus water vapor.

Composition:Active gases: N2, O2, H2; Inert gases: Ar, Ne, He, Kr, Xe, Rn;Variable gases: CO2, O3, H2O (vapors).Water may be present as gas, solid or liquid. Water vapors, though, are always present. The

smaller particles within the atmosphere, which are too small to fall out rapidly (size 10 -110-3m)form aerosols. Without aerosols clouds, rain and snow could not form.

Mechanical properties Air is highly compressible, such that its lower layers are much moredense than those above. Fifty percent of the total mass of the air is found below 5 km and theaverage density decreases from 1.2 kg/m3 at the surface to 0.7 kg/m3 at 5 000 m. Pressure ismeasured as a force per unit area - 1 mb being equal to a force of 100 newtons acting on 1 m 2. Theatmosphere is able to support 760 mm mercury column or 1 atm is equal to 1013 mb. This sea levelpressure decreases with height about 1 mb per each 8 m.

Structure - layering of the atmosphere The atmosphere is layered into six distinct wellmarked zones of contrasting temperature due to differential absorption of solar energy. The patternconsists of three relatively warm layers.

The Lower Atmosphere

Troposphere this is the lowest layer of air immediately adjacent to Earths surface (918km height). It is in this zone that most weather events occur. It contains about 75% of the mass ofthe whole atmosphere. Its composition is relatively uniform as it is constantly stirred by winds. Air

temperature drops rapidly with increasing altitude (6.25OC/km) in this layer reaching -60C at thetop. A sudden reversal of this temperature creates a sharp boundary (tropopause) that limits mixingbetween the troposphere and upper zones.

Stratosphere this zone extends from the troposphere from 16-18 km up to about 50 km.Air temperature in this zone is stable or even increases with higher altitude. It has similarcomposition as troposphere except for two components water (1000 times less) and ozone (1000times more). The stratosphere contains much of the total atmospheric ozone from 22 up to 25 km (itreach a peak density at approximately 22 km). The ozone absorbs the most of the incoming solar

ultraviolet radiation from the sun. Unlike the troposphere, the stratosphere is relatively calm thereis very little mixing in it.

The Upper Atmosphere

Mesosphere from 50 up to 80 km - in this zone the temperature diminishes even more

the minimum temperature here is -90C. At altitude of 80 km another abrupt temperature changeoccurs showing the beginning of the next zone. Noctilucent clouds are observed over high altitudesin summer due to meteoric dust particles which act as nuclei for ice crystals. Pressure is very low from 1 mb/50 km to 0.01 mb/90 km.

Thermosphere from 80 to 500 km. The lower part of the thermosphere rich of highlyionized gases started from 100 km up to 300 km is called ionosphere. The temperature in this zone

is very high as molecules are constantly being bombarded by high-energy solar and cosmicradiation (x-rays, and ultraviolet radiation) which cause ionization. The density of the moleculesand ions here is very low as well.


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Exosphere from 500 up to 750 km - atoms of oxygen, hydrogen and helium form thetennous atmosphere. Helium is produced by action of cosmic radiation on nitrogen, hydrogen - bybreakdown of water vapor and methane.

Magnetosphereover 1 000 to 60 000 km Electrons and protons are derived from the solarwind. The charged particles are concentrated at above 3 000 and 16 000 km height as radiation

belt and are result of trapping by the Earths magnetic field. Plasmasphere and radiation belt are

layers of the magnetosphere.

Destruction of Stratospheric Ozone. The Antarctic ozone hole recurs every springtime.Unfortunately network and data used evaluating the changes in O3 layer are available only forlimited geographical regions. Substantial uncertainties remain in defining changes in the verticaldistribution of O3, because satellite data record is so short (less than 1 cycle) so it is not possible todistinguish between solar induced and human influenced contributions to the changes in O3concentrations. In the future, any changes concerning the stratospheric ozone depend mainly onfuture emissions of CFCs, CH4, N2O, and CO2.

EFFECTS OF THE STRATOSPHERIC OZONE DEPLETION

Ozone is a gas found throughout the atmosphere, but most highly concentrated in the stratosphere, between 10 and 50km above sea level, where it is known as the 'ozone layer'. Without the ozone layer, life on the Earth's surface would notbe possible: it protects us from the damaging ultra-violet radiation of the sun; in particular it filters out UV-B radiation.Recent evidence has shown that certain parts of the ozone layer are becoming thinner, ozone 'holes' have developed.The discovery of the ozone hole was the first evidence that human activities are changing the global environment Theconsequence of any thinning of the ozone layer is that more UV-B radiation reaches the Earth's surface. UV-B radiationaffects DNA molecules, causing damage to the outer surface of plants and animals. In humans it causes skin cancer,leads to eye disease, and is a general immuno-suppressant..

Formation of the ozone layer

Two billion years ago life on Earth was confined to a few micro-organisms living underwater. These organisms had the

ability to photosynthesise - they existed on the basis of sunlight. As a by-product of the photosynthesis, oxygen wasreleased into the atmosphere. Some of this oxygen reached the stratosphere, where it began to react with incoming ultra-violet radiation from the sun to form ozone. Over a period of several million years, the ozone layer was formed.

Depletion of the ozone layer

Atmospheric ozone is continually broken-down and reformed; until recently this process has been in a state of naturalbalance. This balance has been upset as a result of human activity; specifically, the manufacture and use of a group ofsynthetic chemical substances known as CFCs and HCFCs. These chlorine-containing compounds, used in aerosols,refrigeration, solvents and foam insulation, have drifted up into the stratosphere. Through a complex series of chemicalchain-reactions, small amounts of these compounds are able to destroy very large quantities of ozone. The result is thatozone is being broken down more quickly than it is forming; parts of the layer are becoming thinner - 'holes' aredeveloping .There are two ozone holes, one each above the North and South pole. These holes result from the fact thatfor each pole, for half of the year, the Earth is tilted so that the pole is constantly being bombarded with UV light. UV

light is needed to cause CFCs or Methyl Bromine to release a Cl or Br atom. Due to this constant bombardment, moreatoms of these two elements are released which allows holes to be made. During the other half of the year, the pole isexposed to lower levels of UV light and thus can regenerate its ozone, which causes the holes to act cyclically.

Effects of ozone layer depletion

The potential consequences for humans, animals, plants, and even building materials are serious:Human health - the greatest threat to human health is an increase in the incidence of skin cancer; each 1% loss of totalozone leads to a 3% to 5% increase in skin cancer cases. In addition, eye disease, including temporary disorders such as'snow blindness', and more permanent conditions, such as cataracts, become more common. These problems arecompounded by the fact that UV-B suppresses the immune system.

Skin Cancer:

Melanoma

Melanoma, the most serious form of skin cancer, is also one of the fastest growing types of cancer in theworld. Many dermatologists believe there may be a link between childhood sunburns and melanoma later inlife.


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Nonmelanoma Skin Cancers

Nonmelanoma skin cancers are less deadly than melanomas. Nevertheless, left untreated, they can spread,causing disfigurement and more serious health problems. There are two primary types of nonmelanoma skincancers.

Basal Cell Carcinomas are the most common type of skin cancer tumors. They usually appear as small, fleshy

bumps or nodules on the head and neck, but can occur on other skin areas. Basal cell carcinoma grows slowly,and rarely spreads to other parts of the body. It can, however, penetrate to the bone and cause considerabledamage.

Squamous Cell Carcinomas are tumors that may appear as nodules or as red, scaly patches. This cancer candevelop into large masses, and unlike basal cell carcinoma, it can spread to other parts of the body.

With proper protection from UV radiation, however, most premature aging of the skin can be avoided.

Cataracts and Other Eye Damage

Cataracts are a form of eye damage in which a loss of transparency in the lens of the eye clouds vision. If left untreated,cataracts can lead to blindness. Research has shown that UV radiation increases the likelihood of certain cataracts.Although curable with modern eye surgery, cataracts diminish the eyesight. Other kinds of eye damage includepterygium (i.e., tissue growth that can block vision), skin cancer around the eyes, and degeneration of the macula (i.e.,

the part of the retina where visual perception is most acute). All of these problems can be lessened with proper eyeprotection from UV radiation.

Immune Suppression

Scientists have found that overexposure to UV radiation may suppress proper functioning of the body's immune systemand the skin's natural defenses. All people, regardless of skin color, might be vulnerable to effects including impairedresponse to immunizations, increased sensitivity to sunlight, and reac-tions to certain medications.

Marine environmentThe phytoplankton and algae are the main producers in the world. They(a) absorb CO2 from the atmosphere, helping tostave off global warming, and (b) form the base of the marine food chain. They live near the top of the ocean and absorba lot of the UV light. This often kills them, resulting in decreased production. Further up the food chain, this means areduction in fish stocks, marine animals, and seabirds.Animals rely on these organisms for food and die off when there is a decrease in the plankton and algae population. An

example of this is penguins in Antarctica. For whales, creatures that spend the greatest time at the ocean surface andupper layers, increased UV exposure could eventually lead to genetic damage and cancer.

Effects on Biogeochemical Cycles

Increases in solar UV radiation could affect terrestrial and aquatic biogeochemical cycles thus altering both sources andsinks of greenhouse and chemically-important trace gases e.g., carbon dioxide (CO2), carbon monoxide (CO), carbonylsulfide (COS) and possibly other gases, including ozone. These potential changes would contribute to biosphere-atmosphere feedbacks that attenua

environmental production engineering

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