Columbia Encyclopedia

Search results

500 results found

nitrogen cycle

(Encyclopedia)CE5 Nitrogen cycle nitrogen cycle, the continuous flow of nitrogen through the biosphere by the processes of nitrogen fixation, ammonification (decay), nitrification, and denitrification. Nitrogen...

soil

(Encyclopedia)soil, surface layer of the earth, composed of fine rock material disintegrated by geological processes; and humus, the organic remains of decomposed vegetation. In agriculture, soil is the medium that...

Oakville

(Encyclopedia)Oakville, town (1991 pop. 114,670), Ont., Canada, on Lake Ontario, between Toronto and Hamilton. A major component of the local economy is the Ford Motor Co plant, one of the largest auto plants in Ca...

loganberry

(Encyclopedia)loganberry, blackberrylike plant of the genus Rubus of the family Rosaceae (rose family). See bramble. ...

Parker Dam

(Encyclopedia)Parker Dam, at the Ariz.–Calif. line, on the Colorado River; completed 1938. It is 320 ft (98 m) high and 856 ft (261 m) long. The dam impounds water for Los Angeles and other coastal cities, has a ...

butterwort

(Encyclopedia)butterwort, common name for several species of the plant genus Pinguicula of the north temperate zone and the mountains of tropical America. It is a member of the family Lentibulariaceae (bladderwort ...

Bernburg

(Encyclopedia)Bernburg bĕrnˈbo͝ork [key], city, Saxony-Anhalt, E Germany, on the Saale River. It has imp...

Polypodiophyta

(Encyclopedia)Polypodiophyta pŏlˌēpōˌdēŏfˈətə [key], division of the plant kingdom consisting of the plants commonly called ferns. The ferns are vascular plants with stems, roots, and leaves. The small an...

botany

(Encyclopedia)botany, science devoted to the study of plants. Botany, microbiology, and zoology together compose the science of biology. Humanity's earliest concern with plants was with their practical uses, i.e., ...

North Dakota State University

(Encyclopedia)North Dakota State University, at Fargo; land-grant and state supported; coeducational; chartered and opened 1890 as North Dakota Agricultural College, achieved university status in 1960. The agricult...