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Title: The impact of land use on salmonids (Report 30) : a study of the River Torridge catchment
Author: I. Naismith
Author: R. Wyatt
Author: J. Gulson
Author: C.P. Mainstone
Document Type: Monograph
The study was established with the overall objective of identifying the factors responsible for the observed deterioration in both salmonid populations and river quality in the River Torridge. This project was initiated to investigate the circumstantial evidence linking changes in agricultural land use to deterioration in both river water quality and salmonid populations. The Torridge Catchment was chosen for the study because a significant decrease in salmonid rod catches has been reported in recent decades along with a general deterioration in river quality. A multidisciplinary environmental investigation undertaken in the mid-1980s by South West Water Authority (SWWA, 1986) concluded that, on the available evidence, there appeared to have been significant environmental deterioration within the river. Major causes were considered to be changes in agricultural land use and practices, reduced flows and the polluting load from sewage treatment works. Surveys of juvenile salmon and trout populations had shown significant decreases in distribution and abundance, whilst an apparent decline in salmon rod catches was considered to be steeper than the national trend.
Publisher: National Rivers Authority
Publication Date: 1996
Publication Place: Bristol
Subject Keywords: Salmon fisheriesWater qualityPopulation dynamicsBiological surveysEnvironmental degradation
Geographic Keywords: Torridge
Taxonomic Keywords: Salmonidae
Extent: 47
Total file downloads: 266

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