In order to explore the spatial distribution characteristics and pollution status of surface sediment nutrients in Dongting Lake, sediment samples at nine representative sampling stations were collected in February of 2012 and April of 2013, and contents of organic matter(OM), total nitrogen(TN) and total phosphorus(TP) in the sediments of each station were measured. The results show that the contents of OM are 1.48%-4.22% with the average value of 2.06%, the contents of TN are 382-2 217 mg/kg with the average value of 1 340 mg/kg, and the contents of TP are 142-716 mg/kg with the average value of 294 mg/kg. Compare with other lakes or reservoirs in China, the contents of OM and TN in Dongting Lake are in the middle level, its endogenous load should not be ignored. The spatial distribution of OM content is similar to that of TN, generally in the order of South Dongting Lake >East Dongting Lake> West Dongting Lake, while TP content is generally in the order of East Dongting Lake > West Dongting Lake > South Dongting Lake. The C/N ratios are 6.1-14.8 with the average value of 10.2. From the point of biological deposition, the OM in surface sediments of Dongting Lake predominantly originates from zooplankton and phytoplankton. Organic index and organic nitrogen assessment results show that Dongting Lake sediment environment is relatively good, overall in clean to just clean category.
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