The researchers studied different forms of phosphorus in sediments from Hongze Lake using a new method. They found that most of the phosphorus in the sediment is inorganic, with a smaller amount being organic. The highest concentrations were in a town near a river and human activities. The main form of inorganic phosphorus was De-P, followed by Fe-P. The levels of Ca-P, Al-P, and Ex-P were low, and Oc-P was the lowest. The distribution of phosphorus forms varied in sediments from different parts of the lake.