Primary production — For other uses, see Primary production (economics). Global oceanic and terrestrial photoautotroph abundance, from September 1997 to August 2000. As an estimate of autotroph biomass, it is only a rough indicator of primary production potential,… … Wikipedia
Primary sector of the economy — The primary sector of the economy generally involves changing natural resources into primary products. Most products from this sector are considered raw materials for other industries. Major businesses in this sector include agriculture,… … Wikipedia
Asia — /ay zheuh, ay sheuh/, n. a continent bounded by Europe and the Arctic, Pacific, and Indian oceans. 2,896,700,000; ab. 16,000,000 sq. mi. (41,440,000 sq. km). * * * I Largest continent on Earth. It is bounded by the Arctic Ocean, the Pacific Ocean … Universalium
Trophic level — First trophic level The plants in this image, and the algae and phytoplankton in the lake, are primary producers. They take nutrients from the soil or the water, and manufacture their own food by photosynthesis, using energy from the sun. The… … Wikipedia
marine ecosystem — Introduction complex of living organisms in the ocean environment. Marine waters cover two thirds of the surface of the Earth. In some places the ocean is deeper than Mount Everest is high; for example, the Mariana Trench and the… … Universalium
Food web — A freshwater aquatic and terrestrial food web. A food web (or food cycle) depicts feeding connections (what eats what) in an ecological community. Ecologists can broadly lump all life forms into one of two categories called trophic levels: 1) the … Wikipedia
Trophic dynamics — In ecology, trophic dynamics is the system of trophic levels (Greek trophē , food), which describe the position that an organism occupies in a food chain what it eats, and what eats it. Energy economy Ecologists study the energy economies of… … Wikipedia
Glossary of environmental science — This is a glossary of environmental science.Environmental science is the study of interactions among physical, chemical, and biological components of the environment. Environmental science provides an integrated, quantitative, and… … Wikipedia
Australia — /aw strayl yeuh/, n. 1. a continent SE of Asia, between the Indian and the Pacific oceans. 18,438,824; 2,948,366 sq. mi. (7,636,270 sq. km). 2. Commonwealth of, a member of the Commonwealth of Nations, consisting of the federated states and… … Universalium
Lentic ecosystems — are the ecosystems of lakes, ponds and swamps. Included in these environments are the biotic interactions (amongst plants, animals and micro organisms) together with the abiotic interactions (physical and chemical).cite book | last = Brown first … Wikipedia
