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Title: Instream Flow Requirements of the River Wissey, Norfolk, Annex C - April 1993
Author: National Rivers Authority Anglian Region
Document Type: Monograph
Annotation: EA additional title info: Loughborough Unversity of Technology - dept of geography - freshwater environments research group - linking hydrology an ecology
This document is one of a series of Annexes which accompany the report The River Wissey: the link between hydrology and ecology' prepared for the National Rivers Authority by the Freshwater Environments Group at Loughborough University. This study describes the use of the Physical Habitat Simulation System (PHABSIM) for prescribing instream flow requirements of the River Wissey, Norfolk. Essentially, PHABSIM is used to relate changes in discharge or channel structure to changes in physical habitat availability for a chosen species. Seven sites were selected along the river. Water depth, velocity and substrate were recorded across seven transects and at three calibration discharges (low, medium and high) at each site. PHABSIM was then used to simulate the hydraulic characteristics of each reach over the full range of flows normally experienced. This information was then combined with habitat suitability criteria for seven species of fish (brown trout, dace, chub, roach, bream, pike and perch) and for four life stages for each (spawning, fry, juvenile and adult) and for four species of aquatic invertebrate ( Leuctra fusca, Rhyacophila dorsalis, Polycentropus flavomaculatus and Sphaerium comeuni). Relationships between discharge and the availability of usable habitat were then defined using PHABSIM and analysed to make recommendations concerning the instream flow requirements of the selected species.
Publisher: National Rivers Authority
Publication Date: 1993
Publication Place: Loughborough
Subject Keywords: RiversChalk streamsHydrologyEcologyWater levelsFlow rateHabitat assessmentFishes
Geographic Keywords: EA AnglianNorfolkWisseyCam and Ely Ouse catchment
Taxonomic Keywords: Salmo truttaLeuciscus leuciscusSqualius cephalusRutilus rutilusAbramis bramaEsox luciusPerca fluviatilis
Extent: 44
Total file downloads: 262

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