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Title: Assessment of the performance of the BMWP scoring system against biological targets and the determination of significant change
Author: National Rivers Authority Anglian Region
Document Type: Monograph
Annotation: EA additional title info: national rivers authority anglian region
Biological data is now playing an important role in improving the precision with which the water quality of a stretch of river is determined. It is important that subjective interpretation of the data is reduced so that an assessment of the performance against biological targets and determination of change over time can be carried out with confidence. In an attempt to investigate the most efficient and informative method of interpreting and assessing the data a series of illustrative experiments involving data manipulation were carried out. Ideally the procedure should make full use of all the data available and incorporate a low level of statistical uncertainty. This then sensitises the procedure so smaller changes in the biological quality of sites may be identified. The EMWP Score is a system used for summarising qualitative data and is considered a reliable method of assessing the biological quality of rivers. It is therefore used widely by the NRA on a national scale together with the ASPI. Data from 140 National reporting sites in the Anglian Region has been used in this report. Each of these sites has been sampled over a ten year period and the EMWP and ASPT values calculated. In this report data from 1988, 1989 and 1990 will used for the analyses.
Publisher: National Rivers Authority
Publication Date: 1996
Publication Place: Peterborough
Subject Keywords: Statistical dataData analysisBiological analysisRiversWater qualityRIVPACS
Geographic Keywords: EA Anglian
Extent: 62
Total file downloads: 245

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