太湖沉积物中营养盐特征及其来源解析

he concentrations of TN, TP, and TOC in the sediment increased twofold, threefold, and twofold, respectively, from 1949 to 2010. The trophic state of Meiliang Bay presents a continuous increasing trend. The impact of LUCCs on environmental changes is significant. Most farmland was converted to urbanized land. The changes in demographic structure induced by LUCCs led to large discharges of TN, TP, and TOC into the water. The intense human activities in the area are likely the main source of TN, TP, and TOC, and the amount of TN, TP, and TOC originating from natural sources (e.g., the decomposition of phytoplankton, terrestrial organic matter and benthic invertebrates) was relatively smaller after 1975. TN, TP, and TOC originate from both natural sources and human activities, but natural sources may be more dominant than human activities in the future.