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lake, body of water

(Encyclopedia)lake, inland body of standing water occupying a hollow in the earth's surface. The study of lakes and other freshwater basins is known as limnology. Lakes are of particular importance since they act a...

salinity of ocean water

(Encyclopedia)salinity of ocean water: see ocean. ...

water on the brain

(Encyclopedia)water on the brain: see hydrocephalus. ...

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 ...

Ontario, Lake

(Encyclopedia)Ontario, Lake, 7,540 sq mi (19,529 sq km), 193 mi (311 km) long and 53 mi (85 km) at its greatest width, between SE Ont., Canada, and NW N.Y.; smallest and lowest of the Great Lakes. It has a surface ...