Study on total phosphorus pollution load estimation and prevention and control countermeasures in Dongting Lake

In order to fight the battle for reducing total phosphorus (TP) in Dongting Lake and continuously improve the water ecological environment of the Yangtze River, this study accounts for the TP pollution load in Dongting Lake. To this end, the sources of the pollutants are analyzed and corresponding prevention and control measures are proposed by comprehensive use of field research and historical data analysis. The obtained results reveal that the annual TP input to the Dongting Lake was 23287 t in 2017, among which the input from four rivers and three lake entrances represent the main source with an annual TP input of 14033 t (including 3681 t from sediment input), accounting for 60.26%. Agricultural pollution is the second largest source of TP input, accounting for 32.69%, while domestic pollution only accounts for 5.93%. Additionally, the contributions of atmospheric deposition and industrial pollution in order are 0.69% and 0.4%. The TP input from moving sources such as birds and waterway shipping is very small, only accounting for 0.03%. Based on the achieved results, this study aims to propose corresponding prevention and control measures in four aspects: interception of river and lake pollution, control of agricultural pollution sources, enhancement of sewage treatment and industrial pollution prevention. (c) 2023 Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).