eutrophication
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GC: n

CT: Eutrophication is characterized by excessive plant and algal growth due to the increased availability of one or more limiting growth factors needed for photosynthesis (Schindler 2006), such as sunlight, carbon dioxide, and nutrient fertilizers. Eutrophication occurs naturally over centuries as lakes age and are filled in with sediments (Carpenter 1981). However, human activities have accelerated the rate and extent of eutrophication through both point-source discharges and non-point loadings of limiting nutrients, such as nitrogen and phosphorus, into aquatic ecosystems (i.e., cultural eutrophication), with dramatic consequences for drinking water sources, fisheries, and recreational water bodies (Carpenter et al. 1998). For example, aquaculture scientists and pond managers often intentionally eutrophy water bodies by adding fertilizers to enhance primary productivity and increase the density and biomass of recreationally and economically important fishes (Figure 1) via bottom-up effects on higher trophic levels (Boyd & Tucker 1998). However, during the 1960s and 1970s, scientists linked algal blooms to nutrient enrichment resulting from anthropogenic activities such as agriculture, industry, and sewage disposal (Schindler 1974). The known consequences of cultural eutrophication include blooms of blue-green algae (i.e., cyanobacteria, Figure 2), tainted drinking water supplies, degradation of recreational opportunities, and hypoxia. The estimated cost of damage mediated by eutrophication in the U.S. alone is approximately $2.2 billion annually (Dodds et al. 2009).

S: http://www.nature.com/scitable/knowledge/library/eutrophication-causes-consequences-and-controls-in-aquatic-102364466 (last access: 11 January 2015)

N: 1. Term: eutrophication. Literally meaning: “well-nourished”. Origin: Anc Greek + τροφή/trophe(=food, nourishment ) > δρέπω/drepo(=gather) ευ-/ eu-(=prefix meaning “well”, “good”, “easy”, “right”).
Coined/History: In 1919 Swedish limnologist Einar Christian Leonard Naumann (1891-1934) introduced into limnology the concepts of oligotrophy (nutrient poor) and eutrophy (nutrient rich).
eutrophic (adj), early 18th century (denoting a medicine promoting good nutrition): from Greek eutrophia, from eu ‘well’ + trephein ‘nourish’. The current sense dates from the 1930s.
2. Eutrophication, the gradual increase in the concentration of phosphorus, nitrogen, and other plant nutrients in an aging aquatic ecosystem such as a lake. The productivity or fertility of such an ecosystem increases as the amount of organic material that can be broken down into nutrients increases. This material enters the ecosystem primarily by runoff from land that carries debris and products of the reproduction and death of terrestrial organisms. Blooms, or great concentrations of algae and microscopic organisms, often develop on the surface, preventing the light penetration and oxygen absorption necessary for underwater life.
3. Eutrophication – “Eutrophication is defined as an increase in the rate of supply of organic matter in an ecosystem.” – Nixon, 1995.
4. Eutrophication – “The process by which a body of water acquires a high concentration of nutrients, especially phosphates and nitrates. These typically promote excessive growth of algae. As the algae die and decompose, high levels of organic matter and the decomposing organisms deplete the water of available oxygen, causing the death of other organisms, such as fish. Eutrophication is a natural, slow-aging process for a water body, but human activity greatly speeds up the process.” – Art, 1993.
5. Eutrophication – “The term ‘eutrophic’ means well-nourished; thus, ‘eutrophication’ refers to natural or artificial addition of nutrients to bodies of water and to the effects of the added nutrients….When the effects are undesirable, eutrophication may be considered a form of pollution.” – National Academy of Sciences, 1969.
6. Eutrophication – “The enrichment of bodies of fresh water by inorganic plant nutrients (e.g. nitrate, phosphate). It may occur naturally but can also be the result of human activity (cultural eutrophication from fertilizer runoff and sewage discharge) and is particularly evident in slow-moving rivers and shallow lakes … Increased sediment deposition can eventually raise the level of the lake or river bed, allowing land plants to colonize the edges, and eventually converting the area to dry land.” – Lawrence and Jackson, 1998.
7. Eutrophic – “Waters, soils, or habitats that are high in nutrients; in aquatic systems, associated with wide swings in dissolved oxygen concentrations and frequent algal blooms.” – Committee on Environment and Natural Resources, 2000.
8. eutrophication: term standardized by ISO.

S: 1. http://bioetymology.blogspot.com.es/2012/02/eutrophication.html (last access: 11 January 2015); OD – http://www.oxforddictionaries.com/definition/american_english/eutrophic (last access: 11 January 2015). 2. EncBrit – http://global.britannica.com/EBchecked/topic/196751/eutrophication (last access: 11 January 2015). 3, 4, 5, 6 & 7. USGS – http://toxics.usgs.gov/definitions/eutrophication.html (last access: 11 January 2015). 8. TERMIUMPLUS.

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CR: coal, ecology, environment, natural gas, petroleum.