Diatoms as indicators of water quality in some English urban lakes

Abstract

1. The paper describes diatom communities from a series of linked urban lakes in relation to water chemistry and uses mullivariate statistical techniques to show how indicator groups can be defined.2. Diatoms are classified into ecological groups using two-way species indicator analysis (TWINSPAN). Each ecological group is assiciated with a specific range of water-quality conditions. The headwater stream environments are differentiated from the lake habitats at level 1. Al level 2 of TWINSPAN, the sampling sites are grouped into five ecological groups. according to their water chemistry and irrespective of the time of year.3. Detrended correspondence analysis (DCA) and principal components analysis (PCA) provide two statistically independent methods of assessing the environmental gradients along which the ecological groups are distributed. The most important physico-chemical parameters are total hardness, specific conductance and pH, followed by phosphates and nitrates.4. Ecological groups I-V correspond to an environmental gradient ranging from the forested headwaters, which are acidic, of low specific conductance, total hardness and nutrient content, through the urban lakes, which are alkaline and of relatively high total hardness, specific conductance and nutrient content.5. Twelve site groups are identified at level 3 of TWINSPAN. each of which corresponds to a narrower range of water-quality conditions within the ecological groupings. A specific diatom assemblage is associated with each site group.6. Benthic diatoms form an intregral part of the diatom assemblages found in the water column and this is identified as a topic for further study.

Comparative Environmental Assessment in the Studies of Benthic Diatom, Macroinvertebrate, and Fish Communities

“…Algal assemblages have been documented to have a high degree of specificity to multiple environmental variables. This has allowed useful TWINSPAN classifications associated with narrow range of water quality conditions (GUZKOWSKA and GASSE, 1990;LELAND, 1995). The diatom TWINSPAN grouping in this study was best discriminated while fish grouping was least discriminated by environmental and spatial variables, suggesting a progressive dissipation of information about the environment along the trophic chain.…”

The Effects of Substrate Type on Diatom-Based Multivariate Water Quality Assessment in a Tropical River (Monjolinho), São Carlos, SP, Brazil

“…This has also been described as an indicator of high organic pollution, low concentrations of DO and eutrophication (Van Dam et al 1994;Lobo et al 2002). G. augur has been considered as an indicator of eutrophic environments (Guzkowska and Gasse 1990), but according to Lobo et al (2002), this species is sensitive to organic pollution.…”

Using Epilithic Diatom Communities to Assess Ecological Condition of Xiangxi River System

“…For example, DAI is sensitive to organic pollution, and TDI is used to infer eutrophication of waters. As most rivers are usually experiencing several kinds of disturbances simultaneously, the accuracy of these indices will decrease owing to interactions among disturbances (Guzkowska and Gasse, 1990). As for community indices, the relationships between anthropogenic influences and respondence of indices are often nonlinear (Boyle et al, 1990;Vannote et al, 1980), so these indices are usually unfit for assessment.…”