By definition, overpopulation is the condition where the number of organisms exceeds the carrying capacity of their habitat. We are facing the effects of overpopulation in our daily lives. Overpopulation has impacted the life of common man and has proved to be one of the gravest difficulties that have to be fought. Overpopulation implies scarcity of resources and economic inflation; these are the monsters which can make life miserable. Living through the negative effects of overpopulation have made us realize serious problems associated with it. It is high time we wake up and find the causes of overpopulation and work on them.
Causes of Overpopulation
Decline in the Death Rate: The fall in death rates that is decline in mortality rate is one fundamental causes of overpopulation. Owing to the advancements in medicine, man has found cures to the previously fatal diseases. The new inventions in medicine have brought in treatments for most of the dreadful diseases. This has resulted in an increase in the life expectancy of individuals. Mortality rate has declined leading to an increase in population.
Owing to modern medications and improved treatments to various illnesses, the overall death rate has gone down. The brighter side of it is that we have been able to fight many diseases and prevent deaths. On the other hand, the medical boon has brought with it, the curse of overpopulation.
Rise in the Birth Rate: Thanks to the new discoveries in nutritional science, we have been able to bring in increase in the fertility rates of human beings. Medicines of today can boost the reproductive rate in human beings. There are medicines and treatments, which can help in conception. Thus, science has led to an increase in birth rate. This is certainly a reason to be proud and happy but advances in medicine have also become a cause of overpopulation.
Migration: Immigration is a problem in some parts of the world. If the inhabitants of various countries migrate to a particular part of the world and settle over there, the area is bound to suffer from the ill effects of overpopulation. If the rates of emigration from a certain nation do not match the rates of immigration to that country, overpopulation makes its way. The country becomes overly populated. Crowding of immigrants in certain parts of the world,
results in an imbalance in the density of population.
Lack of Education: Illiteracy is another important cause of overpopulation. Those lacking education fail to understand the need to prevent excessive growth of population. They are unable to understand the harmful effects that overpopulation has. They are unaware of the ways to control population. Lack of family planning is commonly seen in the illiterate lot of the world. This is one of the major factors leading to overpopulation. Due to ignorance, they do not take to family planning measures, thus contributing to a rise in population.
Effects of Overpopulation:
Water and Air Pollution
- Water Pollution
America’s Troubled Waters, a report by US Public Interest Research Groups (U.S. PRIG), cites the following statistics regarding the state of America’s waterways:
- Approximately 39% of our rivers, 46% of our lakes, and 51% of our estuaries are still too polluted for
- Pollution caused nearly 20,000 beach closings in 2004, the highest level in 15 years.
- In 2004, 31 states had statewide fish consumption advisories in place because of toxic pollution.
to be in poor condition.
- According to American Rivers and the website healthy rivers.org: Eighty percent of streams contain insecticides, drugs, or other chemicals.
- During 2002 and 2003, in just Wisconsin, Iowa, Minnesota and Missouri, pollution in rivers and streams
- killed 3.5 million fish. The number of miles of rivers containing fish that may be harmful to your health due to pollution,
- increased from 2% to 14% from 1993 to 2001.Waterborne germs and parasites cause an estimated 7.1 million mild-to-moderate cases of infectious
- disease in the U.S. annually. Every year more than 1.2 trillion gallons of untreated sewage, storm water and industrial waste are
- discharged into U.S. waters. The EPA warns that sewage levels in our rivers could be back to 1970s levels by the year 2016.
- Air Pollution
The Environmental Defense Fund reports that 80% of the cancer risks from air pollutants nationwide is from mobile transportation sources. As our cities and suburbs continue to grow at record pace, pollution emitted by
commuters will only grow worse.About 70 percent of the heavy construction equipment used in California in 2005 was old enough not to have to
face any emission control regulations, according to the Union of Concerned Scientists.
According to the air pollution program of Clear the Air, a collective of grassroots and environmental organizations dedicated to combating global warming:
Electricity generation is our nation’s largest source of air pollution and greenhouse gas emissions.
- The Clean Air Act and other environmental measures have not succeeded in lowering power plant pollution.
- … EPA and other studies have shown that far greater reductions are needed to meaningfully reduce the public health and environmental damage caused by SO2 emissions from power plants.
- Fine particle pollution results in the premature deaths of more than 45,000 people in the U.S. each year.
- While our air quality has improved in the U.S. since the inception of the Clean Air Act of 1970, more than 88 million Americans still live in areas with unsafe levels of fine particle pollution.
- In 2004, fine particle pollution exceeded the annual and/or daily national health standard at air quality monitors in 55 small, mid-sized, and large metropolitan areas located in 21 states and home to 96 million people.
Carrying capacity
There is wide variability both in the definition and in the proposed size of the Earth's carrying capacity, with estimates ranging from less than 1 to 1000 billion humans (1 trillion). A 2001 UN report said that two-thirds of the estimates fall in the range of 4 billion to 16 billion (with unspecified standard errors), with a median of about 10 billion. More recent estimates are much lower, particularly if resource depletion and increased world affluence are considered.
In a study titled Food, Land, Population and the U.S. Economy, David Pimentel, professor of ecology and agriculture at Cornell University, and Mario Giampietro, senior researcher at the US National Research Institute on Food and Nutrition (INRAN), estimate the maximum U.S population for a sustainable economy at 200 million. And in order to achieve a sustainable economy and avert disaster, the United States would have to reduce its population by at least one-third, and world population would have to be reduced by two-thirds.
Some groups (for example, the World Wide Fund for Nature and Global Footprint Network ) have stated that the carrying capacity for the human population has been exceeded as measured using the Ecological Footprint. In 2006, WWF's"Living Planet Report" stated that in order for all humans to live with the current consumption patterns of Europeans, we would be spending three times more than what the planet can renew. Humanity as a whole was using, by 2006, 40 percent more than what Earth can regenerate.
But critics question the simplifications and statistical methods used in calculating Ecological Footprints. Therefore Global Footprint Network and its partner organizations have engaged with national governments and international agencies to test the results – reviews have been produced by France, Germany, the European Commission, Switzerland, Luxembourg, Japan and the United Arab Emirates. Some point out that a more refined method of assessing Ecological Footprint is to designate sustainable versus non-sustainable categories of consumption.However, if yield estimates were adjusted for sustainable levels of production, the yield figures would be lower, and hence the overshot estimated by the Ecological Footprint method even higher.
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