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Environmental Protection Agency

(Encyclopedia)Environmental Protection Agency (EPA), independent agency of the U.S. government, with headquarters in Washington, D.C. It was established in 1970 to reduce and control air and water pollution, noise ...

toxic waste

(Encyclopedia)toxic waste is waste material, often in chemical form, that can cause death or injury to living creatures. It usually is the product of industry or commerce, but comes also from residential use, agric...

biosphere

(Encyclopedia)biosphere, irregularly shaped envelope of the earth's air, water, and land encompassing the heights and depths at which living things exist. The biosphere is a closed and self-regulating system (see e...

hydrology

(Encyclopedia)hydrology, study of water and its properties, including its distribution and movement in and through the land areas of the earth. The hydrologic cycle consists of the passage of water from the oceans ...

aquaculture

(Encyclopedia)aquaculture, the raising and harvesting of fresh- and saltwater plants and animals. The most economically important form of aquaculture is fish farming, an industry that accounts for an ever increasin...

Carson Sink

(Encyclopedia)Carson Sink, swampy area, c.100 sq mi (260 sq km), W Nev.; a remnant of ancient Lake Lahontan. Fallon National Wildlife Refuge is located there. The Carson River (c.125 mi/200 km long), fed by melted ...

United Nations Conference on Environment and Development

(Encyclopedia)United Nations Conference on Environment and Development (UNCED) or Earth Summit, an 11-day meeting held in June, 1992, in Rio de Janeiro, Brazil, to discuss the global conflict between economic devel...

Jamaica Bay

(Encyclopedia)Jamaica Bay, c.20 sq mi (50 sq km), SW Long Island, SE N.Y., separated from the Atlantic Ocean by Rockaway Peninsula; the Rockaway Inlet links it to the sea. The shallow bay has many islands, and its ...

acid rain

(Encyclopedia)acid rain or acid deposition, form of precipitation (rain, snow, sleet, or hail) containing high levels of sulfuric or nitric acids (pH below 5.5–5.6). Produced when sulfur dioxide and various nitro...

Chicago, river, United States

(Encyclopedia)Chicago, river, formed in Chicago by the junction of its North Branch (24 mi/39 km long) and South Branch (10 mi/16 km long), and flowing southeast via a canal into the Des Plaines River at Lockport, ...