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Title: Distribution of Azolla in the Great Ouse catchment
Author: National Rivers Authority Anglian Region
Document Type: Monograph
Following the Central Area Fisheries September a request was made to investigate the distribution of the Water Fern (Azolla Filiculoides) in the Middle Level system. Fish mortalities in the Forty Foot Drain and in the Twenty Foot River were suspected to have been associated with its occurrence. Advisory Committee meeting on the 26 Accordingly surveys of the main drains in the Middle Level system were carried out on 30 September 1991 and 1 October 1991. Approximately 60 sites were inspected and the occurrence and abundance of Azolla noted. In addition Central Area staff were requested to supply information on sightings in other parts of the Great Ouse catchment. This report summarises the findings of those surveys and gives information on the biology and on the control of Azolla. A brief account of the occurrence and distribution of Azolla in the Middle Level system since 1988 is also given, based on information provided by Geoff Cave, of the Middle Level IDB.
Publisher: National Rivers Authority
Publication Date: [1992]
Publication Place: Peterborough
Subject Keywords: Aquatic plantsRiver fisheriesWater qualityRiversPlant ecologyGeographical distribution
Geographic Keywords: Great OuseIvelCam
Extent: n.p. [11]
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