The importance of considering biological processes when setting total maximum daily loads (TMDL) for phosphorus in shallow lakes and reservoirs

摘要: Total maximum daily loads (TMDL) are required by the US Environmental Protection Agency for pollutants that have impaired designated uses of surface waters in nation. Setting an appropriate TMDL requires quantitative information on both external pollutant inputs and processes affecting dynamics within ecosystem. Here we focus phosphorus (P), a globally important freshwater lakes. We consider how biological (including those related to algae, plants, invertebrates fish) can influence ability lakes assimilate P, turn managers select TMDLs. The primary is shallow eutrophic lakes, with Lake Okeechobee (Florida, USA) serving as case study. paper deals only in-lake they relate setting not subsequent issue load allocation among pollution sources. results indicate lake P substantially reduced when surplus levels occur water column, phytoplankton becomes dominated cyanobacteria, benthic invertebrate community oligochaetes, submerged plant biomass low. If some these changes be reversed rehabilitation program then may able support higher TMDL.