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Title: Modelling phytoplankton development in the proposed Cardiff Bay Barrage
Author: Wallace Evans
Document Type: Monograph
This report is intended to supplement, rather than to replace, the final report submitted by the Freshwater Biological Association, entitled "Algal growth in the proposed Cardiff Bay Barrage" in November, 1987. The latter provided an assessment of the limnological conditions likely to obtain in the proposed freshwater lake and the way these would impact upon the dynamics and potential biomass of aquatic algae and higher plants. Its essential conclusions were that the lake was liable to be dominated by phytoplankton, the extent of which would be regulated primarily by the continued fluvial discharge through the lake: at winter flows, most algae would be removed from the lake at a faster rate than could be recouped through growth in situ and, as a result, biomass would remain far below the carrying capacity determined by temperature, light and especially the undoubtedly high nutrient loads emanating from the inflowing rivers. In the summer months, however, when potential growth rates of algae are elevated and fluvial discharges typically decline, net increase was shown to be probable and in a very dry summer, biomass might achieve very high proportions. In the light of more detailed data on nutrient loads, provided by Welsh Water, the original projection that nutrients would become limiting had to be revised in favour of a worst-case in which the population would become self-shaded by its own biomass, at a level approaching 500-600 mg chlorophyll by cubic metre.
Publisher: Freshwater Biological Association
Publication Date: 1988
Publication Place: Ambleside
Subject Keywords: PhytoplanktonDynamicsBiomassAlgal bloomsNutrientsTemperatureLightRespirationModellingGreen algaeCyanophyceaeChlorophyll a
Geographic Keywords: WalesCardiff
Extent: 65
Total file downloads: 26

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