Phytoplankton Water Quality Relationships in U. S. Lakes. Part VII: Comparison of Some New and Old Indices and Measurements of Trophic State

摘要

Thirty-eight indices and measurements of trophic state were compared to evaluate their relative abilities to trophically rank a test set of 44 eastern and southeastern U.S. lakes, representing 17 states. Lake rankings based upon total phosphorus and chlorophyll a levels served as standards for evaluation of the indices by Spearman Rank Correlation procedures. The new phytoplankton community-based indices turned in 4 of the top 5 performances against the chlorophyll a standard, while Secchi disk transparency, phosphorus loading models, multivariate analyses, and total Kjeldahl nitrogen provided strong rank correlations with total phosphorus.