Variation partitioning of diatom species data matrices: Understanding the influence of multiple factors on benthic diatom communities in tropical streams.
Elucidating the confounding influence of multiple environmental factors on benthic diatom communities is important in developing water quality predictive models for better guidance of stream management efforts. The objective of this study was to explore the relative impact of metal pollution and hydromorphological alterations in, addition to nutrient enrichment and organic pollution, on diatom taxonomic composition with the view to improve stream diatom-based water quality inference models. Samples were collected twice at 20 sampling stations in the tropical Manyame Catchment, Zimbabwe. Diatom, macroinvertebrate communities and environmental factors were sampled and analysed. The variations in diatom community composition explained by different categories of environmental factors were analysed using canonical correspondence analysis using variance partitioning (partial CCA). The following variations were explained by the different predictor matrices: nutrient levels and organic pollution - 10.4%, metal pollution - 8.3% and hydromorphological factors - 7.9%. Thus, factors other than nutrient levels and organic pollution explain additional significant variation in these diatom communities. Development of diatom-based stream water quality inference models that incorporate metal pollution and hydromorphological alterations, where these are key issues, is thus deemed necessary.
Department of Freshwater and Fishery Science, Chinhoyi University of Technology, Chinhoyi, Zimbabwe. Electronic address: tbere2015@gmail.com.
Taurai
T
Bere
Department of Freshwater and Fishery Science, Chinhoyi University of Technology, Chinhoyi, Zimbabwe.
Tinotenda
T
Mangadze
Department of Freshwater and Fishery Science, Chinhoyi University of Technology, Chinhoyi, Zimbabwe.
Tongai
T
Mwedzi
D000818:Animals; D058448:Biota; D017377:Diatoms / Q000145:classification*; D020387:Food Chain; D062070:Hydrology; D007448:Invertebrates / Q000145:classification / Q000502:physiology; D008670:Metals / Q000032:analysis; D045483:Rivers; D014874:Water Pollutants, Chemical / Q000032:analysis; D060753:Water Quality; D015030:Zimbabwe
D008670:Metals; D014874:Water Pollutants, Chemical
Diatoms; Eutrophication; Hydromorphological factors; Metal pollution; Organic pollution