Environment of the United States
From Wikipedia, the free encyclopedia
The environment of the United States comprises diverse biotas, climates, and geologies. Environmental regulations and the environmental movement have aimed to respond to environmental threats.
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[edit] Biota
With habitats ranging from tropical to Arctic, U.S. plant life is very diverse. The country has more than 17,000 identified native species of flora, including 5,000 in California (home to the tallest, the most massive, and the oldest trees in the world).[1] More than 400 mammal, 700 bird, 500 reptile and amphibian, and 90,000 insect species have been documented.[2] Wetlands such as the Florida Everglades are the base for much of this diversity. The country's ecosystems include thousands of nonnative exotic species that often harm indigenous plant and animal communities.
Many plant and animal species became extinct soon after first human settlement, including the North American megafauna; others have become nearly extinct since European settlement, among them the American Bison and California Condor.[3]
[edit] Climate
The U.S. climate is temperate in most areas, tropical in Hawaii and southern Florida, polar in Alaska, semiarid in the Great Plains west of the 100th meridian, Mediterranean in coastal California and arid in the Great Basin. Its comparatively generous climate contributed (in part) to the country's rise as a world power, with infrequent severe drought in the major agricultural regions, a general lack of widespread flooding, and a mainly temperate climate that receives adequate precipitation.
Following World War II, the West's cities experienced an economic and population boom. The population growth, mostly in the Southwest, has strained water and power resources, with water diverted from agricultural uses to major population centers, such as Las Vegas and Los Angeles. According to the California Department of Water Resources, if more supplies are not found by 2020, residents will face a water shortfall nearly as great as the amount consumed today.[4]
[edit] Geology
The lower 48 states can be divided into roughly five physiographic provinces: the American cordillera, the Canadian Shield, the stable platform, the coastal plain, and the Appalachian orogenic belt.
[edit] Environmental law and conservation
The Endangered Species Act of 1973 protects threatened and endangered species and their habitats, which are monitored by the U.S. Fish and Wildlife Service.
In 1872, the world's first national park was established at Yellowstone. Another fifty-seven national parks and hundreds of other federally managed parks and forests have since been formed.[5] Wilderness areas have been established around the country to ensure long-term protection of pristine habitats. Altogether, the U.S. government regulates 1,020,779 square miles (2,643,807 km²) , 28.8% of the country's total land area.[6] Protected parks and forestland constitute most of this. As of March 2004, approximately 16% of public land under Bureau of Land Management administration was being leased for commercial oil and natural gas drilling;[7] public land is also leased for mining and cattle ranching.
The United States is the second largest emitter, after China, of carbon dioxide from the burning of fossil fuels.[8] The energy policy of the United States is widely debated; many call on the country to take a leading role in fighting global warming.[9]
[edit] Environmental movement
In the United States today, the organized environmental movement is represented by a wide range of organizations sometimes called non-governmental organizations or NGOs. These organizations exist on local national and international scales. Environmental NGOs vary widely in political views and in the amount they seek to influence the government. The environmental movement today consists of both large national groups and also many smaller local groups with local concerns. Some resemble the old U.S. conservation movement - whose modern expression is the Nature Conservancy, Audubon Society and National Geographic Society - American organizations with a worldwide influence.
[edit] See also
[edit] References
- ^ Morse, Larry E., et al.. Native Vascular Plants. Our Living Resources. U.S. Dept. of the Interior, National Biological Service. Retrieved on 2006-06-14.[broken citation]
- ^ Our Living Resources. U.S. Dept. of the Interior, National Biological Service. Retrieved on 2006-06-14.[broken citation]
- ^ Pleistocene Megafauna Extinctions
- ^ A World Without Water -Global Policy Forum- NGOs
- ^ National Park Service Announces Addition of Two New Units. National Park Service (2006-02-28). Retrieved on 2006-06-13.
- ^ Federal Land and Buildings Ownership. Republican Study Committee (2005-05-19). Retrieved on 2006-06-13.
- ^ Abuse of Trust: A Brief History of the Bush Administration’s Disastrous Oil and Gas Development Policies in the Rocky Mountain West. Wilderness Society (2007-05-28). Retrieved on 2007-06-11.
- ^ Vidal, John, and David Adam (2007-06-19). China Overtakes US as World's Biggest CO2 Emitter. Guardian. Retrieved on 2007-06-27.
- ^ U.S. Faces International Pressure on Climate Change Policy. Online NewsHour. PBS (2005-07-05). Retrieved on 2007-05-05.
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