Occurrence characteristics of nitrogen and phosphorus in sediments of the"river-lake"system in Chaohu Lake basin
As a large watershed with many tributaries,Chaohu Lake basin was a typical"river-lake"system.Surface sediments were collected from rivers and lakes in Chaohu Lake basin,and various forms of nitrogen and phosphorus were determined.The results showed that the various forms of nitrogen in the sediment of Chaohu Lake basin were as follows:organic and sulfide bound nitrogen(321.2 mg/kg)＞ion-exchange nitrogen(191.2 mg/kg)＞ferromanganese oxidized nitrogen(79.6 mg/kg)＞carbonate bound nitrogen(43.3 mg/kg),with seasonal variations having the most significant effect on ion-exchange nitrogen.And the various forms of phosphorus were iron and aluminum bound phosphorus(331.3 mg/kg)＞calcium bound phosphorus(220.7 mg/kg)＞organic phosphorus(186.5 mg/kg),with seasonal variations having the most significant effect on iron and aluminum bound phosphorus.The comprehensive pollution index evaluation showed that the total nitrogen and total phosphorus pollution levels in the sediment of Chaohu Lake basin were mild and moderate,respectively.
"river-lake"systemChaohu Lake basinnitrogen formphosphorus formrelease risk
NETL
NSTL
万方数据
