Postsettlement eutrophication histories of six British Columbia (Canada) lakes

Paleolimnological analyses of diatoms were used to quantitatively assess eutrophication trends for the last 150 yr in six British Columbia lakes. A transfer function was used to infer past lake-water total phosphorus concentrations from the sedimentary diatom assemblages in ²¹⁰Pb-dated sediment cores: all lakes had relatively high total phosphorus levels (>13 μg/L) prior to European settlement. Three lakes showed significant eutrophication since that time; the others were only mildly affected. Total phosphorus inferences using the transfer function satisfactorily estimated the modern total phosphorus concentrations of the six study lakes. -from Authors