以武汉东湖为研究对象,分析并比较了3个采样点柱状沉积物中各种形态氮、磷的垂向分布,并结合pH进行了研究.结果表明:东湖沉积物pH小于上覆水中pH并随沉积物深度增加呈下降趋势.总氮与总磷均为处于湖湾区的1号点最高,2号点湖心最低,3号点居中.氨氮和硝酸盐氮也表现为1号点远远大于2号点和3号点.随着近年治污力度的加大,1号点的氮磷水平呈下降趋势,但是3号点受面源污染影响,氮、磷水平上升很快,甚至在表层已经和1号点持平,磷虽然仍然是东湖最主要的限制性营养元素,但受硝化与反硝化作用及聚磷菌的影响,近20a来,东湖沉积物总氮含量下降很大,氯磷比仅为3左右。
Vertical distributions of species of nitrogen and phosphorus in the sediments of three sampling sites in Lake Donghu were examined and analyzed, pH was combined to be studied at the same time. The results showed that the pH values in sediments were lower than those in overlying water and decreased with depth. The highest concentration of TN and TP occurred in Station 1, where suffered from heavy domestic sewerage. The lowest concentration of TP and TN presented to Station 2, which is located at the center of Lake Donghu. The concentrations of dissolved ammoniac nitrogen (DAN) and dissolved nitrate nitrogen (DNN) of station 1 were higher than the other stations. In recent years, along with the pollution treatment measures, the concentration of TN and TP in station 1 presented a trend of decline. However, the concentration of TN and TP ascends very fast in station 3 and it has been as high as station 1 on the surface sediments. Although phosphorus is the most restricting nutritious element all the same, the concentration of TN descended greatly in the last two decades because of the combined effect of nitrification, denitrification and phosphorus removing bacteria. As a result, the N/P ratio is only about 3.