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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, ...

eutrophication

(Encyclopedia)eutrophication yo͞otrōˌfĭkāˈshən [key], aging of a lake by biological enrichment of its water. In a young lake the water is cold and clear, supporting little life. With time, streams draining i...

Delaware, river, United States

(Encyclopedia)Delaware dĕlˈəwâr, –wər [key], river, c.280 mi (450 km) long, rising in the Catskill Mts., SE N.Y., in east and west branches, which meet at Hancock. It flows SE along the New York–Pennsylvan...

cryptosporidium

(Encyclopedia)cryptosporidium krĭpˌtōspərĭdˈēəm [key], genus of protozoans having at least four species; they are waterborne parasites that cause the disease cryptosporidiosis. One of the species appears to...

speleology

(Encyclopedia)speleology spēlēŏlˈəjē [key], systematic exploration of caves, popularly called spelunking. It includes the measuring and mapping of caves and reporting on the flora and fauna found in them. One...

sanitary science

(Encyclopedia)sanitary science, principles of health preservation, embracing hygiene, on an individual level, and public health, on a communal level. Those who specialize in sanitary science are sanitary engineers....

environmentalism

(Encyclopedia)environmentalism, movement to protect the quality and continuity of life through conservation of natural resources, prevention of pollution, and control of land use. The philosophical foundations for ...