Deforestation is the "permanent removal of standing forests," as the U.S. Environmental Protection Agency defines it. Although suburban sprawl, industry and agriculture still pose major threats, U.S. deforestation has somewhat stabilized, in part due to a wave of forest management and environmental protection laws enacted in the later decades of the 20th century. In many other countries, however, particularly those with large areas of rain forest and boreal forest, deforestation is rampant (see References 2), and the global effects are serious.
Deforestation, current and past, is a serious problem around the world, particularly in tropical areas. Countries with significant deforestation include Thailand, Brazil, the Congo and Indonesia, as well as parts of Eastern Europe, according to GRID-Arendal, a UN Environment Programme collaborating center. (See References 4)
Deforestation affects the earth's physical environment by causing soil erosion, poor water quality, reduced food security and impaired flood protection, according to a report from the World Resources Institute. Because forests are the source of employment and food for many people, their destruction can cause mass migration to cities. With the influence that tropical forests have on weather, particularly rain, deforestation can cause altered weather patterns. (See References 3)
When massive swaths of forest are destroyed, species loss follows. Tropical areas, like Brazil's rain forests, have the world's highest concentrations of biologically diverse species. When the habitat for plants and animals is cut down or burned, species that may not be present anywhere else on Earth disappear. In addition, deforestation of tropical forests leaves many species of migrating birds without a winter home. (See References 3)
Deforestation is a main cause of the higher concentrations of greenhouse gases in the atmosphere. In particular, deforestation causes high levels of carbon dioxide: it is released when forests are burned or when they decompose, and when trees that used to take in this carbon dioxide are cut down, levels rise. Greenhouse gases are trapped in the atmosphere and act as a barrier for heat that would normally be released into space; as a result, temperatures across the globe rise and change rainfall patterns, ice cover and sea levels. (See References 1 and 2)
- U.S. Environmental Protection Agency; Climate Change; April 2011
- U.S. Environmental Protection Agency; Human-Related Sources and Sinks of Carbon Dioxide; April 2011
- U.S. Environmental Protection Agency; Biological Diversity; Lauretta M. Burke and Ross A. Kiester; December 1989
- UNEP GRID-Arendal; Areas Affected by Deforestation; 2002
- NPR; The Amazon Road: Paving Paradise For Progress?; Lourdes Garcia-Navarro; September 2009
Elizabeth Smith has been a scientific and engineering writer since 2004. Her work has appeared in numerous journals, newspapers and corporate publications. A frequent traveler, she also has penned articles as a travel writer. Smith has a Bachelor of Arts in communications and writing from Michigan State University.
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