How Are Humans Hurting the Environment?

Humans are by far the biggest contributors to environmental degradation. It is predicted that the next mass extinction to occur will be human induced. Humans live unsustainably, depleting the earth's resources faster than they are replenished and producing enormous amounts of waste that pollutes the environment and destroys the habitats of many plant and animal species.

Resource Depletion

• One of the earth's primary resource is its rainforests, of which approximately 13 million hectares are cleared annually. In the Amazon alone, close to 70 percent of forest area is already gone. Deforestation occurs for human activities such as animal farming, biofuel crops and road construction. This contributes to a multitude of problems including habitat destruction, greenhouse gas emissions, decreases in soil fertility and erosion.

Pollution

• Most waste produced from human activities such as farming, energy production and basic everyday living is improperly disposed of and contains an extensive range of contaminants that pollute air, land and water sources. A few include pharmaceuticals, microorganisms and toxic chemicals. For example, nitrogen-based chemical fertilizers seep into groundwater causing eutrophication, which impacts on both the survival of aquatic wildlife and on drinking-water quality.

Global Warming

• The human contribution to global warming is substantial and according to the greenhouse theory is the leading cause of climate change. Greenhouse gases are said to trap radiation and produce a warming effect on the earth. In addition to carbon dioxide, humans add large quantities of potent greenhouse gases to the atmosphere, such as methane, chlorofluorocarbons, nitrous oxide and acid rain-inducing ammonia. These gases originate mainly from the energy and agricultural sectors.

Biodiversity Loss

• All of these environmental factors directly contribute to species extinction. According to the Millennium Ecosystem Assessment, extinction threatens one-third of all amphibians, one-eighth of all birds and one-fifth of all mammals -- a prediction that does not include undiscovered species. This abuse of other species inevitably leads to the loss of vital ecosystem services needed by humans such as seed dispersal, pollination, air and water purification and nutrient recycling.