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Title: Classification options for trophic status
Author: W. Parr
Author: S.C. Nixon
Author: S. Ashley
Author: D. Woodrow
Document Type: Monograph
Annotation: EA additional title info: Draft Final Report; R and D Project 423
The overall objective as described in the project investment appraisal is: "To review the options for including a reliable and practical assessment of trophic status in terms of algal productivity in a general classification scheme for estuaries and coastal waters in England and Wales". The Water Act 1989, now consolidated into the Water Resources Act 1991, requires that all controlled waters may be subject to a system of classification and that Statutory Water Quality Objectives (SWQOs) may be set in relation to such waters by the Secretary of State. After lengthy consultations the NRA has proposed that there would be different Use Classifications (UCs) for setting targets relating to the actual or potential use of the water, on a statutory basis i.e. Statutory Water Quality Objectives, plus a General Quality Assessment (GQA) scheme, for assessing general overall progress on a periodic basis. The GQA scheme would periodically examine the general state of the waters using different criteria - basic chemical, biological, aesthetic and nutrient status. It was also recognised by the NRA that such a GQA scheme for estuaries and coastal waters might be improved if a direct assessment of trophic status could be included with an assessment of nutrient levels.
Publisher: National Rivers Authority
Publication Date: 1993
Publication Place: Bristol
Subject Keywords: Trophic levelsWater analysisAlgaeCoastal watersEstuaries
Extent: 87
Total file downloads: 33

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