The current world population growth is slightly above 1 percent per year. Considering that there are, as of 2011, nearly seven billion people on Earth, that figure, though small, is significant. Analysis of the world's ecosystems, such as coastal, forest, grassland, freshwater and agricultural ecosystems, indicates that increased population is stressing many of these ecosystems and results in a environmental decline.
While the issue of global warming is still being debated, scientific evidence points to the fact that heavy industrialization and pollution have contributed and continue to contribute to rising temperatures. The increase in human population -- from a little over 1.5 billion people at the turn of the twentieth century to close to 7 billion people by 2011 -- combined with the advent of the automobile, industry and especially the burning of fossil fuels, along with the destruction of the rainforest and increased agriculturalization, combine to add to the development of a heat-trapping blanket in the earth's atmosphere. This results in a worldwide rise in temperature. Overpopulation is a contributing factor in the phenomenon of global warming.
Destruction of Habitat
Increased population leads to the destruction of habitats by putting pressure on inhabitants for limited resources. Forests are denuded and animals are killed for food as a result of competition for resources. In developed countries, an increase in human population leads to the development of once pristine areas. As more affluent city dwellers move to the suburbs, suburban sprawl leads to the sale of farmland and forests for housing developments. This affects the environment as well as the aesthetic appeal of formerly undeveloped areas.
Endangerment to Species
The stress that population growth places on an ecosystem can result in endangerment to species of animals. Some animals survive only in highly specialized ecosystems. If environmental stress is too great, or if waste disposal or treatment is underutilized, pollution and destruction of habitat can cause some species to become in danger of extinction.
Overpopulation's Effect on Coral Reefs in Coastal Areas
Biodiversity is an important factor in the health of coral reefs. Camilo Mora, researcher at Dalhousie University, concluded in a study on the effects of human population growth on coral reefs that there is a direct connection between unsustainable human population growth and a decline in biodiversity in coral reefs. This is significant because over 80 percent of countries with coral reefs are expected to double their population within 50 to 100 years. This puts into question the survival of many of these coral reefs without serious attention to safeguarding these fragile ecosystems.