We collected quantitative data on macrophyte abundance and water quality in 319 mostly shallow, polymictic,
Florida lakes to look for relationships between trophic state indicators and the biomasses of plankton algae,
periphyton, and macrophytes. The lakes ranged from oligotrophic to hypereutrophic with total algal chlorophylls
ranging from 1 to 241 mg m−3. There were strong positive correlations between planktonic chlorophylls and
total phosphorus and total nitrogen, but there were weak inverse relationships between the densities of periphyton
and the trophic state indicators total phosphorus, total nitrogen and algal chlorophyll and a positive relationship
with Secchi depth. There was no predictable relationship between the abundance of emergent, floating-leaved,
and submersed aquatic vegetation and the trophic state indicators. It was only at the highest levels of nutrient
concentrations that submersed macrophytes were predictably absent and the lakes were algal dominated. Below
these levels, macrophyte abundance could be high or low. The phosphorus–chlorophyll and phosphorus–Secchi
depth relationships were not influenced by the amounts of aquatic vegetation present indicating that the role of
macrophytes in clearing lakes may be primarily to reduce nutrient concentrations for a given level of loading.
Rather than nutrient concentrations controlling macrophyte abundance, it seems that macrophytes acted to modify
nutrient concentrations. (Emphasis mine - RJS)
PDF on research gate.
Also by Bachman: "Factors determining the distributions of total phosphorus, total nitrogen, and chlorophyll a in Florida lakes"