Development of the Phosphorus Dynamic Model in Sediment-Water System and Assessment of Eutrophication Control Programs Available to Purchase

The multi-component dynamic model was developed for phosphorus in the sediment-water system in order to obtain quantitative information on the bottom sediment-water interactions of Lake Kasumigaura, a highly eutrophic lake. The ranges of model calculations of phosphorus release fluxes and phosphorus concentrations in the sediment of Lake Kasumigaura were in fair agreement with those of the observed data. The phosphorus dynamics of the upper layers (0-3 cm) of the sediment seemed to regulate the phosphorus transportation from the sediment to the overlying water. The effectiveness of eutrophication control programs in Lake Kasumigaura was assessed using the calibrated model. The reduction of the phosphorus deposition rate to the sediments, artificial aeration, and phosphorus inactivation were more effective than the sediment dredging and bottom sealing for the control of phosphorus release from the sediments.