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Title: Mesotrophic rivers in Anglian region : phase 1 June 1994
Author: D.M. Harper
Document Type: Monograph
Annotation: EA additional title info: mesotrophic rivers in anglian region phase 1
This document records the results of a preliminary review of the trophic status of rivers within Anglian Region and recommends further research and policy objectives for those of low nutrient status. Mesotrophic rivers are those moderately low in nutrients, in a range where eutrophic are those high in nutrients, and oligotrophic low. In the lowlands of Britain, there are no naturally oligotrophic rivers, because a measurable nutrient load derives from the natural geologies of the catchments. There is far less knowledge available about the trophic status of rivers than there is of lakes, which have been extensively classified by their nutrient, especially phosphorus, input. It is generally recognised however, that in aquatic systems, the limiting nutrient is phosphorus rather than nitrogen. This preliminary review examined the levels of phosphorus in Anglian rivers from routine monitoring data collected in 1992 and classified rivers on a 5 class system from 1, high, to 5, low. The major impact of nutrient enrichment is observed upon plant communities, and we examined the available information for selected Anglian rivers from past published records and from the REDS database built up from River Corridor Surveys. We conclude that, at present, the most effective measure of oligotrophic status is low phosphate concentrations measured in the routine water quality monitoring process. Many small streams do not have monitoring stations on them however, so a surrogate for this is low effluent input.
Publisher: National Rivers Authority
Publication Date: 1994
Publication Place: Peterborough
Subject Keywords: EutrophicationPhosphorusNitratesRiversTrophic levelsEffluentsDischarge (hydrology)
Geographic Keywords: EA AnglianNarNorth West Norfolk catchmentNorfolk
Extent: 34
Total file downloads: 257

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