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Over Population Essay, Research Paper

The Enviromnetal Degradation as a Result of Overpopulation 1Introduction There are simply too many people on our planet, and the population is not showing any signs ofslowing down(see Figure 1). It is having disastrous effects on our environment. There are too manyimplications and interrelationships to discuss in this paper, but the three substances that our earthconsists of: land, water and air, are being destroyed. Our forests are being cut down at an alarmingrate, bearing enormous impacts on the health of earth. Our oceans and seas are being polluted andoverfished. Our atmosphere is injected with increasing amounts of carbon dioxide, which hurts theentire planet. All of these problems can be traced to our vast, rapidly expanding population, which hasstressed our world far too greatly.Our Population In 1994, the world population was 5 602 800 000. This population had a doubling time of onlyforty-one years (De Blij and Muller, 1994, p.527). The massive amount of people has had highlydestructive impacts on the earth s environment. These impacts occur on two levels: global and local. Onthe global level, there is the accumulation of green house gases that deplete the ozone layer, theextinction of species, and a global food shortage. On the local level, there is erosion of soils (andthe loss of vegetation), the depletion of water supply, and toxification of the air and water. The earthis dynamic though, all of these aspects are interrelated, and no one impact is completely isolated. Allof these destructive elements can be traced to our enormous population. As the population increases, sodo all of the economic, social, and technological impacts. The concept of momentum of population growth is one that must be considered. It states thatareas with traditionally high fertility rates will have a very young structure age. Thus, a decrease inthe fertility rate will still result in a greater absolute number of births, 2as there are more potential mothers. Populations are very slow in adjusting to decreases in fertilityrates. This is especially frightening when considering that South Asia has a population of 1 204 600000 (and a doubling time of thirty two years), Subsaharan Africa has 528 000 000 (doubling time: thirtyone years), and North Africa/Southwest Asia has 448 100 000 (doubling time: twenty seven years) (De Blijand Muller, 1994, p. 529-531)and all of these areas have traditionally high fertility rates. Although third world countries do have a far larger population than industrialized nations, andthe trend is constantly increasing, their populations should not bear the responsibility for our population-enduced degrading environment. The impact we make on the biosphere is sometimes expressedmathematically by ecological economists as I = PAT. I being impact, P population, A affluence(consumption) , and T technology (environmentally bad technology)(Ehrlich and Ehrlich, 1990, p.24).Concern regarding population increases often focuses on the third world, since it is there that growth isexponential. Yet, it is necessary to recognize that people are by no means equal or identical in theirconsumption, and thus their impact on the environment (see Map 2). 3Our Forests The sky is held up by the trees. If the forest disappears the sky, which is the roof of the worldcollapses. Nature and man perish together. – Amerindian legend Forests are a precious link in the life systems of our planet. They are a part of these vitalecosystem services without which earth would not have been habitable by the human species in the firstplace and would certainly have become inhabitable again. Forests have crucial roles in the carbon,nitrogen, and oxygen cycles that nourish and sustain life on earth. They protect the watersheds thatsupport farming and influence climate and rainfall(Lindahl-Kiessling, 1994, p.167). They save the soilfrom erosion and are home to thousands of species, and forest peoples whose lives depend on them. Theyare also a source for industrial and medical purposes. In developing countries, much deforestation is for both local purposes and for export. The UNFPA(United Nations Fund for Population Activities) said in it s 1990 report that population growth may havebeen responsible for as much as eighty percent of the forest land cleared between 1971 and 1986 to makeroom for agriculture, cattle ranching, houses, roads and industries(Ramphal, 1992, p.55). It is estimated that in that period nearly sixty million hectares of forest were converted to farmland and asimilar amount of forest was put to non-agricultural uses. This is equivalent to the mass of twelvehundred square metres of forest added to the population(Ramphal, 1992, p. 57). Quite often, areas of forest were cleared in such a way (ex.: slash and burn) that they willnever grow back. After a forest area has been converted to grazing lands or intensive farming, the soilwill only sustain it for a few years. Then the land is left lifeless. The increasing demand for fuel wood as populations expand is another important factor leading todeforestation. In most developing areas, wood is the primary source of fuel. In many of these areas,the demand for fuel wood is rising at about the rate of population growth, and ahead of the destructioncommitted by loggers (see Figure 2) 4(Hardaway, 1994, p.201). People are spreading out further and further to reach fresh forested areas to meet their fuel needs. It should also be noted that when wood is unavailable, animal dung is burned forfuel. This diverts a great value of nutrition from the soil. Developed countries deplete their forests at a rate that is just as alarming, and are a greatsource of the demand for wood from developing countries. The primary use of this wood is for industrialpurposes, i.e. the construction of goods and capital goods. Again, the consumption of individuals hereis far greater than those in the third world, so their impacts are not much different overall. The reduction of forest land possesses two main environmental dangers. Forests are great naturalrepositories of carbon. Trees breathe in carbon dioxide and store it, acting as carbon reservoirs. Assuch, they are invaluable agents in keeping the level of carbon in the atmosphere stable. As forestsare destroyed worldwide, especially by burning, carbon dioxide is released into the air, adding to thestock of greenhouse gases that are now warming our planet and changing its climate. The adverse of thisnegative effect of forest loss on climate is the positive role of forests in regulating the atmosphereand climate through their life-support services(see Tables 1 and 2)(Ramphal, 1992, 69). Forest land is also the world s main storehouse of species, the plants , animals, birds, andinsects with which earth has been blessed. Tropical forests expand roughly between ten degrees North andsouth of the equator. In a small portion of the earth lies nearly half of earth s biological species,many endemic. The rapid rate of deforestation is erasing our bio-diversity. Desertification is closely related with deforestation. Again, forests are quite often cleared inan especially destructive manner, rendering them lifeless. This eventually leaves the land barren.Agricultural pressures are the other prime population-enduced source of 5 desertification. Increasing populations in developing countries drive people into drier and drierregions to farm. Attempting to farm in areas that are already poor or unsuitable may damage the soils irreparably. Another indirect cause is as population increases in these villages, sodoes the number of goats, which are a source of meat and milk. The goats (which multiply rapidly aswell) are left to roam the countryside, and erode the soils greatly while doing so(Lourdes, 1994,p.376)(see Map 1). Our forests are invaluable resource to all. Not just for the wood, but as they maintain life onearth. They are continuing to be destroyed at a rate that will not permit their return when humanity realizes its errors. Our forests are perhaps the most threatened aspect of earth as a result ofpopulation growth, and the one that we can least afford to lose. 6Our Oceans Roll on, thou deep and dark blue Ocean — roll! Ten thousand fleets sweep over thee in vain; Man marks the earth with ruin – his control Stops with the shore. – from Childe Harold, by Byron In the early 1990 s, the state of the world s fisheries made headlines. Many coastal areas ofNorth America have tried to limit their catches, or halt them all together. It has been recognized thatfurther harvesting could destroy a valuable food resource and aquatic bio-diversity. Our populationgrowth has begun to out pace that of the aquatic life. These steps against vast ocean harvesting are reversing the trend of recent decades. A globalseafood harvest of twenty two million tons in 1950 increased to one hundred million tons in 1989(seeFigure 3)(Brown, 1994, p. 82). For the average person, seafood consumption doubled. All of this did notoccur without consequences. The U.N. Food and Agriculture Organization concluded that seventeen of the world s major fishingregions are currently harvested at or beyond their capacity, and nine are in a state of decline(Ramphal,1992, p. 35). A lack of proper management will only lead to further. As the thought of a future globalfood shortage looms, overfishing could become especially destructive. Whereas overfishing is a direct method of humanity and overpopulation depleting fish stocksworldwide, pollution is an indirect way. The Aral Sea between Kazakhstan and Uzbekistan yielded fortythousand tons of seafood in 1960(Brown and Kane, 1994, p. 94). The river that fed it was diverted forirrigation. The sea became increasingly salty, and is now biologically dead. Approximately one third ofthe world population lives within sixty kilometres of a coastline(Ehrlich and Ehrlich, 1970, p.125).This obviously leaves the oceans and lakes vulnerable to a great deal of pollution(see Map 1). Therun-off of water tainted with phosphates from fertilizers is a major contributor. In many underdevelopedcounties (and to a lesser extent, developed countries) unprocessed sewage 7and industrial waste is pumped or dumped directly into rivers and oceans. Global warming also has aneffect on the world s fisheries. The increased ultra violet rays that enter our atmosphere killphytoplankton in the Arctic by an increased twenty percent(Brown and Kane, 1994, p. 118). These are agreat resource of marine production, as they are the beginning of the aquatic food chain. As populations of many municipalities grow, their sewage treatment facilities are quicklyoutgrown. Industry grows as well, spewing a vast array of contaminants into our water supply: lead,detergents, sulfuric acid, hydrofluoric acid, phenols, benzenes, ammonia and so on(Ehrlich and Ehrlich,1970, p.203). As population and industry grow, so does the need for increased agricultural production.This results in a heavier water-borne load of pesticides, herbicides and nitrates. A result is thespread of pollution in streams, rivers, lakes and along seashores. This spread of pollution is notconfined to just these regions, as it also enters the groundwater where purification is almost impossible. The oceans are a precious source of food. If they were lost, there would be a greater focus onagriculture. Agricultural streeses are already ruining the planet. Thus, the oceans must be carefullymonitored, to assure that they are not being overexploited. Pollution into water is also destroying the fish and aqua culture. This could lead to a great loss of the planet s bio-diversity. That in itselfhas untold consequences. 8Our Atmosphere Think how the crown of earth s creation Will murder that which gave him birth, Ripping out the slow womb of earth – from The Golden Gate, by Vikram Seth The water vapour and carbon dioxide naturally present in our atmosphere absorb and block justenough escaping warmth to keep the planet at an average temperature of fifteen degrees Celsius(Ramphal,1992, p. 97). As the amount of carbon dioxide in the atmosphere increases, more and more heat is keptin. Carbon dioxide is also the gas emitted when we burn fossil fuels; thus an increase in the amount offossil fuel burned results in more carbon dioxide in the environment. We also add new greenhouse gaseslike CFC s which are compounds of our own making. Together, these two groups of emissions, producedprimarily by developed countries, account for some eighty percent of global warming(Arizpe, 1994.p.12). Carbon dioxide emissions and CFC s are removed very slowly from the environment. The Inter-Governmental Panel on Climate Change warned that even if all human made emissions of carbondioxide were halted by the year 1990, about one half of the increase in carbon d!ioxide concentration caused by human activities would still be evident in 2100 (Ramphal, 1992, p. 119). Carbon dioxide accounts for half of global warming, and fossil fuels account for two-thirds ofmanmade carbon dioxide(Ehrlich and Ehrlich, 1970, p.134). The consumption of energy from fossil fuels.Coal, oil, and natural gas used for industrial, commercial, residential, transportation and otherpurposes results in large emissions. Thus, the energy sector accounts for nearly half of global warming,forty six percent. Industry through CFC s, accounts for almost another quarter, twenty four percent.The remaining quarter or so is shared by forestry, through deforestation, and by agriculture 9through methane from livestock and rice cultivation(Ramphal, 1992, p. 201). With action to phase out CFC s already spurred by the alarm over depletion of the ozone layer, it is clearly the consumption of energy from fossil fuels that attention must be focused on if humanity is toface up to the implications of global warming(see Map 2). Highly corrosive sulfuric acids and nitric acids are formed when oxides of sulfur and nitrogencombine with water vapour in the air(Lourdes, 1994, p.158). These oxides are spewed out as gasesprimarily by electricity-generating plants, smelters, and industrial boilers that burn coal and oil.Nitrogen oxides also come from automobile exhaust. The acids return to earth in rain, snow, and fog, andare also deposited directly from the air and trees. The pollutants travel long distances on prevailingwinds, of course taking no account of national borders, so that the sulfur dioxide produced in onecountry often ends up in another. Many polluted areas rainfall in the world can fall as low as 3.5 on the pH scale, which isbetween the acid content of apple juice and lemon juice(Ehrlich and Ehrlich, 1990, p.182). Most fish dieat pH levels below five. Thus, many lakes and streams around heavily polluted areas are left withoutfish. Even at 3.5, which is the OECD norm, we are accepting rain that is a hundred more times acidicthan it should be(Brown, 1994, p.182). Not only fish and lakes and rivers are dying, but forests aswell. The IPCC estimated that if emissions of greenhouse gases continues to grow as currentlyprojected, global mean temperatures will increase at the rate of about 0.3 degrees Celsius each decadeover the next century, which is a rate of increase greater than that ever seen over the past ten thousandyears(Ramphal, 1992, p. 77). These predicted changes seem small, but are actually of great magnitude. Arise of even a degree or two could have severe repercussions, altering patterns of rainfall,intensifying drought, raising the sea level, causing floods and storms, and affecting farming, theavailability of food, and 10health(Ramphal, 1992, p. 77). What nature has tried to bring about over millennia may be achieved infour decades. It may also seem that this gradual warming may benefit countries in the upper latitudes, but in the long run there would be no winners. These changes will be to suddenfor ecosystems to cope. The increase of greenhouse gases into our atmosphere could also accelerate the end of life onearth. The depletion of the ozone harms virtually all aspects of life. The forests are the only factorkeeping this under some degree of control, and they are being destroyed. The ozone layer has shownrecent signs of recuperation, and it is absolutely necessary. 11Conclusions Humanity is breeding itself into a corner. If population growth continues on its current path,ecosystems will be subjected to greater and greater stresses of various sorts. Since the world is sodynamic, and all the types of impacts made on the environment, including those not directly mentioned inthis paper, are interrelated, blame cannot truly be laid on any one section of the world. Not on theunderdeveloped countries with the majority of the population and fastest growth, nor the developedcountries whose affluence highly exceeds that of those in the underdeveloped countries. A concertedeffort will be required by all nations to minimize their impacts. The primary goal for most developing countries should be to reduce their fertility rates. Thiswill require a great deal of birth control and family planning. Medical needs and technologies will alsobe required to improve conditions so that families do not feel the need to have as many children. Thereis a minor fear that if conditions are improved too greatly, that these people will seek and obtain theaffluence of those in the developed countries, and potentially become even more destructive towards theenvironment. Developed countries must seek to reduce both their affluence and (environmentally bad)technology. Government regulations must become stricter regarding the impacts made on the environmentby all sectors of the economy (industrial, residential, etc.). Economics is closely associated with population related environmental degradation. With theincreased population comes an increase in demand for absolutely everything. Industries compete to gettheir products and services out at the lowest possible cost, often without much regard towards theenvironment. Overpopulation of our planet could prove to be cataclysmic. The next few generations may live ina world that is far, far worse off than we currently are. If society 12is to continue along it s current trends, the environment will collapse, and drag humanity with it. It will simply not be enough to try and improve technology. Birth rates must be drastically cut , in a the most humane way possible. Merely focusing on one specific aspect of theseimpacts will not suffice other. The biosphere is woven in a very complicated manner. We are unravelingit quickly, and it must be stopped to preserve Earth in all its beauty.20BIBLIOGRAPHY1. Arizpe, Lourdes. Population and Environment. Boulder: Westview Press, 1994.2. Brown, Lester and Kane, Hal. Full House. New York: Norton and Co., 1994.3. De Blij, H.J. and Muller, Peter O. Geography: Realms, Regions and Concepts. New York: John Wileyand Sons, 1994.4. Ehrlich, Paul and Ehrlich, Anne. Population Explosion. New York: Simon and Schuster, 1990.5. Ehrlich, Paul and Ehrlich, Anne. Population Resources Environment. San Francisco: WiltFreeman and Co., 1970.6. Hardaway, Robert. Population, Law, and Environment. Westport, CT: Praeger, 1994.7. Lindahl-Kiessling, Kerstin. Population, Economy, Development and Environment. Oxford: OxfordUniversity Press, 1994.8. Lutz, Wolfgang. The Future Population of the World. London: Earthscan Publications Ltd.,1994) 9. Ramphal, Shridath. Our Country, The Planet. London: Lime Tree, 1992.10. Schlaepfer, Rudolph. Long Term Implications of Climate Change and Air Pollution on ForestEcosystems. Vienna: IUFRO, 1994.11. Stanford, Quentin H. Canadian Oxford World Atlas. Toronto: Oxford University Press, 1993.


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