ANALYSIS OF THE CHARACTERISTICS OF NITROGEN,PHOSPHORUS,AND ORGANIC MATTER IN SEDIMENTS OF THE NANSI LAKE AFTER THE SOUTH-TO-NORTH WATER DIVERSION PROJECT
This paper analyzed water quality indicators,total nitrogen(TN),total phosphorus(TP),and organic matter(OM)content in sediments and their correlations by collecting water samples and columnar sediments from the typical waters of the Nansi Lake after the completion of the East Route of the South-to-North Water Diversion Project.The results showed that the TN content in the sediments of the Nansi Lake ranged from 750 to 6290 mg/kg with an average of 3402 mg/kg;The TP content ranged from 873 to 1289 mg/kg with an average of 1127 mg/kg,showing significant homogenization;The content of OM in sediments ranged from 3.20%to 13.85%with an average of 9.37%.Attention should be paid to the harm of excessive OM to benthic organisms.The results showed that the water quality of the Nansi Lake was at a moderate eutrophication level,and the contents of TN,TP,and OM in the sediment were rich and slowly increasing.Correlation analysis showed that the correlation between water quality and sediments were not significant,while the correlation between sediment TN and OM was significant(P<0.01).The C/N ratio in the sediment ranges from 12.95 to 21.37 with an average value of 16.72±1.44,which indicates that the organic matter source of the Nansi Lake is mainly terrestrial input.Therefore,continuous attention should be paid to the ecological and environmental governance issues of the Nansi Lake.
sedimentwater qualitycorrelationthe Nansi Lakethe South-to-North Water Diversion Project