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Title: Development of the Acid Water Indicator Community (AWIC) Macroinvertebrate Family and Species Level
Author: J Davy-Bowker
Author: M T Furse
Author: J F Murphy
Author: R T Clarke
Author: R Wiggers
Author: H M Vincent
Author: Environment Agency
Document Type: Monograph
Annotation: Environment Agency Project ID:EAPRJOUT_1057, Representation ID: 319, Object ID: 2330
The forthcoming EU Water Framework Directive will place new statutory requirements on the Environment Agency to assess and remediate pressures on surface water bodies including the acidification of streams and rivers. Biomonitoring will play a key role because target quality will be set using ecological criteria. It is therefore of great importance that a suitable index of acidification stress is developed in readiness for the implementation of the Directive. This report reviews one of the most commonly used macroinvertebrate acidification metrics (the University of Wales system) and presents two new scoring systems developed by CEH during this R and D contract 'AWIC(fam)' and 'AWIC(sp)' (the Acid Waters Indicator Community, family and Species scoring systems). In developing the new family level AWIC(fam) scoring system, it was important that the scoring system would be applicable across the whole of England and Wales and that the level of invertebrate identification was the same as the BMWP scoring system (developed principally to assess the impact of organic pollution). Regression analysis of the AWIC(fam)-ASPT versus mean pH gave rise to a predictive equation enabling mean pH (within defined confidence limits) to be calculated from the AWIC(fam)-ASPT at a test site. These predictions compared favourably with the observed mean pH in a substantial partially independent data set. A species level scoring system, AWIC(sp), has also been developed. Because of the difficulty in obtaining a large independent species level data set (with pH) for testing, an equation predicting the mean pH from AWIC(sp)-ASPT scores has not yet been developed. However, the AWIC(sp) looks very promising and a testing exercise will be carried out. CEH recommend that the AWIC(fam)-ASPT scoring system is included in statutory monitoring programmes carried out by the Environment Agency. CEH also recommend that permissive monitoring programmes carried out in areas of England and Wales that are susceptible to acidification, should make use of AWIC(fam)-ASPT to assess acidity. In future, both the AWIC(fam)-ASPT and AWIC(sp)-ASPT should be included in special investigations of acidification so that the effectiveness of both indices can be evaluated as a precursor to possible use in the Water Framework Directive reporting of acidic stress in England and Wales. In order to make the AWIC scoring systems available to Environment Agency biologists, it is recommended that both scoring systems should be incorporated into the Environment Agency Biology for Windows database. CEH also intend to include the AWIC scoring systems in the next version of the RIVPACS software.
Publisher: Environment Agency
Subject Keywords: Water qualityAcidificationMacroinvertebratesRiversLakesIndicator speciesInvertebratesZoobenthosMonitoring
Extent: 53
Total file downloads: 231

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