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The Enviromnetal Degradation As A Result Of Overpopulation Essay, Research Paper
There are simply too many people on our planet, and the population is not showing any signs of
slowing down(see Figure 1). It is having disastrous effects on our environment. There are too many
implications and interrelationships to discuss in this paper, but the three substances that our earth
consists of: land, water and air, are being destroyed. Our forests are being cut down at an alarming
rate, bearing enormous impacts on the health of earth. Our oceans and seas are being polluted and
overfished. Our atmosphere is injected with increasing amounts of carbon dioxide, which hurts the
entire planet. All of these problems can be traced to our vast, rapidly expanding population, which has
stressed our world far too greatly.
In 1994, the world population was 5 602 800 000. This population had a doubling time of only
forty-one years (De Blij and Muller, 1994, p.527). The massive amount of people has had highly
destructive impacts on the earth’s environment. These impacts occur on two levels: global and local. On
the global level, there is the accumulation of green house gases that deplete the ozone layer, the
extinction of species, and a global food shortage. On the local level, there is erosion of soils (and
the loss of vegetation), the depletion of water supply, and toxification of the air and water. The earth
is dynamic though, all of these aspects are interrelated, and no one impact is completely isolated. All
of these destructive elements can be traced to our enormous population. As the population increases, so
do all of the economic, social, and technological impacts.
The concept of momentum of population growth is one that must be considered. It states that
areas with traditionally high fertility rates will have a very young structure age. Thus, a decrease in
the fertility rate will still result in a greater absolute number of births,
as there are more potential mothers. Populations are very slow in adjusting to decreases in fertility
rates. This is especially frightening when considering that South Asia has a population of 1 204 600
000 (and a doubling time of thirty two years), Subsaharan Africa has 528 000 000 (doubling time: thirty
one years), and North Africa/Southwest Asia has 448 100 000 (doubling time: twenty seven years) (De Blij
and 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, and
the 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 expressed
mathematically 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 is
exponential. Yet, it is necessary to recognize that people are by no means equal or identical in their
consumption, and thus their impact on the environment (see Map 2).
“The sky is held up by the trees. If the forest disappears the sky, which is the roof of the world
collapses. 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 vital
ecosystem services without which earth would not have been habitable by the human species in the first
place 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 that
support farming and influence climate and rainfall(Lindahl-Kiessling, 1994, p.167). They save the soil
from erosion and are home to thousands of species, and forest peoples whose lives depend on them. They
are 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 have
been responsible for as much as eighty percent of the forest land cleared between 1971 and 1986 to make
room 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 a
similar amount of forest was put to non-agricultural uses. This is equivalent to the mass of twelve
hundred 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 will
never grow back. After a forest area has been converted to grazing lands or intensive farming, the soil
will 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 to
deforestation. 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 destruction
committed by loggers (see Figure 2)
(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 for
fuel. 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 great
source of the demand for wood from developing countries. The primary use of this wood is for industrial
purposes, i.e. the construction of goods and capital goods. Again, the consumption of individuals here
is 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 natural
repositories of carbon. Trees breathe in carbon dioxide and store it, acting as carbon reservoirs. As
such, they are invaluable agents in keeping the level of carbon in the atmosphere stable. As forests
are destroyed worldwide, especially by burning, carbon dioxide is released into the air, adding to the
stock of greenhouse gases that are now warming our planet and changing its climate. The adverse of this
negative effect of forest loss on climate is the positive role of forests in regulating the atmosphere
and 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, and
insects with which earth has been blessed. Tropical forests expand roughly between ten degrees North and
south 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 in
an especially destructive manner, rendering them lifeless. This eventually leaves the land barren.
Agricultural pressures are the other prime population-enduced source of
desertification. Increasing populations in developing countries drive people into drier and drier
regions 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, so
does the number of goats, which are a source of meat and milk. The goats (which multiply rapidly as
well) 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 on
earth. 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 of
population growth, and the one that we can least afford to lose.
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 of
North America have tried to limit their catches, or halt them all together. It has been recognized that
further harvesting could destroy a valuable food resource and aquatic bio-diversity. Our population
growth has begun to out pace that of the aquatic life.
These steps against vast ocean harvesting are reversing the trend of recent decades. A global
seafood harvest of twenty two million tons in 1950 increased to one hundred million tons in 1989(see
Figure 3)(Brown, 1994, p. 82). For the average person, seafood consumption doubled. All of this did not
occur without consequences.
The U.N. Food and Agriculture Organization concluded that seventeen of the world’s major fishing
regions 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 global
food shortage looms, overfishing could become especially destructive.
Whereas overfishing is a direct method of humanity and overpopulation depleting fish stocks
worldwide, pollution is an indirect way. The Aral Sea between Kazakhstan and Uzbekistan yielded forty
thousand tons of seafood in 1960(Brown and Kane, 1994, p. 94). The river that fed it was diverted for
irrigation. The sea became increasingly salty, and is now biologically dead. Approximately one third of
the 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). The
run-off of water tainted with phosphates from fertilizers is a major contributor. In many underdeveloped
counties (and to a lesser extent, developed countries) unprocessed sewage
and industrial waste is pumped or dumped directly into rivers and oceans. Global warming also has an
effect on the world’s fisheries. The increased ultra violet rays that enter our atmosphere kill
phytoplankton in the Arctic by an increased twenty percent(Brown and Kane, 1994, p. 118). These are a
great 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 quickly
outgrown. 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 the
spread of pollution in streams, rivers, lakes and along seashores. This spread of pollution is not
confined to just these regions, as it also enters the groundwater where purification is almost
The oceans are a precious source of food. If they were lost, there would be a greater focus on
agriculture. Agricultural streeses are already ruining the planet. Thus, the oceans must be carefully
monitored, 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 itself
has untold consequences.
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 just
enough 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 kept
in. Carbon dioxide is also the gas emitted when we burn fossil fuels; thus an increase in the amount of
fossil fuel burned results in more carbon dioxide in the environment. We also add new greenhouse gases
like CFC’s which are compounds of our own making. Together, these two groups of emissions, produced
primarily 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 carbon
dioxide 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 of
manmade 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 other
purposes 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
through 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 to
face up to the implications of global warming(see Map 2).
Highly corrosive sulfuric acids and nitric acids are formed when oxides of sulfur and nitrogen
combine with water vapour in the air(Lourdes, 1994, p.158). These oxides are spewed out as gases
primarily 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, and
are also deposited directly from the air and trees. The pollutants travel long distances on prevailing
winds, of course taking no account of national borders, so that the sulfur dioxide produced in one
country often ends up in another.
Many polluted areas rainfall in the world can fall as low as 3.5 on the pH scale, which is
between the acid content of apple juice and lemon juice(Ehrlich and Ehrlich, 1990, p.182). Most fish die
at pH levels below five. Thus, many lakes and streams around heavily polluted areas are left without
fish. Even at 3.5, which is the OECD norm, we are accepting rain that is a hundred more times acidic
than it should be(Brown, 1994, p.182). Not only fish and lakes and rivers are dying, but forests as
The IPCC estimated that if emissions of greenhouse gases continues to grow as currently
projected, global mean temperatures will increase at the rate of about 0.3 degrees Celsius each decade
over the next century, which is a rate of increase greater than that ever seen over the past ten thousand
years(Ramphal, 1992, p. 77). These predicted changes seem small, but are actually of great magnitude. A
rise 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, the
availability of food, and
health(Ramphal, 1992, p. 77). What nature has tried to bring about over millennia may be achieved in
four 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 sudden
for ecosystems to cope.
The increase of greenhouse gases into our atmosphere could also accelerate the end of life on
earth. The depletion of the ozone harms virtually all aspects of life. The forests are the only factor
keeping this under some degree of control, and they are being destroyed. The ozone layer has shown
recent signs of recuperation, and it is absolutely necessary.
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 so
dynamic, and all the types of impacts made on the environment, including those not directly mentioned in
this paper, are interrelated, blame cannot truly be laid on any one section of the world. Not on the
underdeveloped countries with the majority of the population and fastest growth, nor the developed
countries whose affluence highly exceeds that of those in the underdeveloped countries. A concerted
effort will be required by all nations to minimize their impacts.
The primary goal for most developing countries should be to reduce their fertility rates. This
will require a great deal of birth control and family planning. Medical needs and technologies will also
be required to improve conditions so that families do not feel the need to have as many children. There
is a minor fear that if conditions are improved too greatly, that these people will seek and obtain the
affluence of those in the developed countries, and potentially become even more destructive towards the
Developed countries must seek to reduce both their affluence and (environmentally bad)
technology. Government regulations must become stricter regarding the impacts made on the environment
by all sectors of the economy (industrial, residential, etc.).
Economics is closely associated with population related environmental degradation. With the
increased population comes an increase in demand for absolutely everything. Industries compete to get
their products and services out at the lowest possible cost, often without much regard towards the
Overpopulation of our planet could prove to be cataclysmic. The next few generations may live in
a world that is far, far worse off than we currently are. If society
is 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 these
impacts will not suffice other. The biosphere is woven in a very complicated manner. We are unraveling
it quickly, and it must be stopped to preserve Earth in all its beauty.
1. 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 Wiley
and 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: Wilt
Freeman and Co., 1970.
6. Hardaway, Robert. Population, Law, and Environment. Westport, CT: Praeger, 1994.
7. Lindahl-Kiessling, Kerstin. Population, Economy, Development and Environment. Oxford: Oxford
University Press, 1994.
8. Lutz, Wolfgang. The Future Population of the World. London: Earthscan Publications Ltd.,
9. Ramphal, Shridath. Our Country, The Planet. London: Lime Tree, 1992.
10. Schlaepfer, Rudolph. Long Term Implications of Climate Change and Air Pollution on Forest
Ecosystems. Vienna: IUFRO, 1994.
11. Stanford, Quentin H. Canadian Oxford World Atlas. Toronto: Oxford University Press, 1993.
TABLE OF CONTENTS
Our Population 1
Our Forests 3
Our Oceans 6
Our Atmosphere 8
LIST OF FIGURES
Figure 1 13
Toatal Projected Population 1990 – 2100 According to Scenario
Figure 2 16
Time Series of Fuelwood and Charcoal Production
Figure 3 17
World Fish Catch, 1950 -1992
Map 1 18
Map 2 19
LIST OF TABLES
Table 1 14
Effects of Global Warming
Table 2 15
Certainty of Climatic Change and It’s Direct Effects on Vegetation
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