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Title: Toxic blue-green algae : a report by the National Rivers Authority
Author: National Rivers Authority
Document Type: Monograph
Blue green algae are organisms with some properties characteristic of both bacteria and algae. They are capable of photosynthesis and the pigment required for this process often gives them a blue green colour. Many species of blue green algae have the ability to fit gaseous nitrogen. Under suitable physical and chemical conditions, particularly in still waters, populations may grow to extremely high densities and, under certain circumstances, a scum of algae will form on the surface which can accumulate downwind. These algae are also known to produce chemicals which can be toxic to mammals, including man. The development of a bloom of blue green algae at Rutland Water in the summer of 1989 resulted in the production of substantial quantities of scum containing toxins, and this led to the deaths of several sheep and dogs which had ingested the scum. An assessment was subsequently made by the NRA of the extent of the potential problem throughout England and Wales. Blooms of blue green algae were found to be widespread, and 60 to 70 per cent of those tested were found to be producing toxins. The results from this 1989 survey, and a description of how the events were managed, are presented in this report. In order for the events of 1989 to be seen in perspective, summaries are given of the present knowledge of the occurrence of blue green algal blooms, their recognised toxins, and the factors affecting the production of both blooms and toxins. Proposals are made for a uniform approach to the problem in the future, and for research to be carried out to improve our understanding and management of waters affected.
Publisher: National Rivers Authority
Publication Date: 1990
Publication Place: London
Subject Keywords: CyanophyceaeAlgal bloomsWater qualityWater reservoirs
Geographic Keywords: Rutland
Extent: 127
Total file downloads: 27

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