Abstract
The response of key organisms to variations in environmental gradients due to geography and climate, pollution and catchment characteristics was examined in mountain lakes in Scotland. Samples were taken from pelagic (zooplankton, bacteria and chlorophyll a) and littoral (benthic invertebrates and epilithic diatoms) zones.Surface sediment samples were taken for analysis of sub-fossil Cladocera, chironomids, diatoms and pigments.
Concentrations of trace metals, persistent organic pollutants and spheroidal carbonaceous particles were also measured. Multivariate techniques were employed.
Biological assemblages of key organisms groups were found to be driven by environmental gradients, like organic content and acid-base status. Low alkalinity lochs with sparse soil coverage at higher altitudes have distinctly different biological communities compared with lochs with high levels of organic matters and high proportion of peaty soils in the catchments.