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Title: Assessing water quality : General Quality Assessment (GQA) scheme for biology (Bilingual Welsh)
Author: Environment Agency
Document Type: Monograph
This brief Environment Agency leaflet describes the General Quality Assessment schem for biolgy. The biological scheme is based on groups of macroinvertebrates (small animals including mayfly nymphs, snails, shrimps and worms) that are found on the river bed. For biological assessment, macroinvertebrates are grouped into 83 taxa. As different taxa respond differently to pollution, they are given scores of 1 (pollution-tolerant taxa) to 10 (pollution-sensitive taxa). The presence of taxa sensitive to pollution suggests better water quality than for sites where only pollution-tolerant taxa are found.
Publisher: Environment Agency
Publication Date: 1996
Publication Place: Bristol
Subject Keywords: RiversWater quality surveysBiological analysisMacroinvertebrates
Geographic Keywords: EnglandWales
Extent: n.p. [4]
Total file downloads: 39

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