于桥水库沉积物中碳氮磷的空间分布特征及污染评价OA

In order to reveal the distribution characteristics of pollutants in the sediment of Yuqiao Reservoir,the contents of total organic carbon(TOC),total nitrogen(TN)and total phosphorus(TP)in the sediments at different depths of Yuqiao Reservoir were measured.The pollution degree of sediments was evaluated by comprehensive pollution index method and or-ganic index method.The results showed that:① The average contents of TOC,TN,and TP in the surface sediment of the studied area were 21.5 mg/g,1 331 mg/kg,and 526 mg/kg,respectively.The distribution characteristics of TN and TOC were similar,with high-value areas concentrated in the north and east of the reservoir,while the high-value areas of TP were concentrated in the east and south of the reservoir.② TOC and TN were mainly enriched in sediment at depths of 0-30 cm,and their vertical variation trends were roughly the same.However,the vertical variation trend of TP was not obvious,and the difference in content between adjacent layers was not significant.③ The average value of the comprehensive pollution index of sediment in Yuqiao Reservoir was 1.48,which indicated a mild pollution level.The average value of the organic index and mass percentage of organic nitrogen were 0.30 and 0.130％,respectively,indicating that the sediment was still clean.