U.S. Army Corps of Engineers U.S. Department of Agriculture
Natural Resources Conservation Service
U.S. Department of the Interior
Bureau of Indian Affairs Bureau of Land Management Bureau of Reclamation
Fish and Wildlife Service Minerals Management Service National Park Service Office of Surface Mining U.S. Geological Survey
U.S. Environmental Protection Agency
Grants permits for dredging and filling in certain waterways, including many wetlands.
Manages more than 190 million acres of public lands in national forests and grasslands. Helps private land owners/managers conserve their natural resources. Participation is voluntary.
Manages 55.7 million acres of land held in trust for American Indians, Indian tribes, and Alaska Natives. Manages 262 million acres of public lands (mostly in the West) and 300 acres of subsurface mineral resources. Provides water and energy to more than 30 million people via hundreds of dams, reservoirs, canals, and power plants it has constructed in 17 western states. Conserves, protects and enhances fish, wildlife, plants and their habitats for the benefit of the public. Manages the nation's natural gas, oil and other mineral resources on the outer continental shelf. Preserves the resources of more than 80 million acres comprising the national park system. Oversees surface mining on federal lands and some tribal and state lands. Provides data related to Earth sciences, natural disasters, and management of natural resources.
Develops and enforces regulations that implement environmental laws enacted by Congress.
*Date of founding of predecessor agency that evolved into current agency. source: Created by Kim Masters Evans for Thomson Gale, 2005
caused by farmers, ranchers, logging and mining companies, and fuel wood collectors. Governments have often encouraged the settlement of land through cheap credit, land grants, and the building of roads and infrastructure. Much of these activities led to the destruction of forests, causing some governments to reverse their policies.
Forests play a particularly crucial role in the global cycling of carbon. When trees are cleared the carbon they contain is oxidized and released into the air, adding to the atmospheric store of carbon dioxide. Many scientists believe that carbon dioxide contributes to global warming. This release happens slowly if the trees are used to manufacture lumber or are allowed to decay naturally. If they are burned as fuel, however, or in order to clear forestland for farming, almost all of their carbon is released rapidly. The clearing for agriculture in North America and Europe has largely stopped, but the burning of tropical forests has taken over the role of producing the bulk of carbon dioxide added to the atmosphere by land use changes.
In 2001 a study published in the journal Science estimated that the forests of the coterminous United States (i.e., excluding Alaska and Hawaii) absorbed 0.14-0.30 petagrams of carbon per year for the period 1980-89 (S. W. Pacala et al, ''Consistent Land- and Atmosphere-Based U.S. Carbon Sink Estimates,'' June 22, 2001). A petagram is 1015 grams. The researchers note that the large carbon ''sink'' supplied by forests is due to ongoing regrowth of trees in large areas of forest that were cleared during the late 1800s and early 1900s for timber and agricultural purposes. They predict that the ''sink'' effect of the forests will gradually diminish as these areas become completely re-vegetated.
The Natural Resources Defense Council (NRDC), a private organization that supports environmental health, reports that nearly half of the forests on the planet have been decimated and every year more than thirty million acres of tropical forests and woodlands are destroyed for agriculture or logging. Exacerbating this problem, global wood consumption is set to double over the next thirty years, according to the NRDC, further stressing the survival of global forests (http://www.nrdc.org).
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