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In order to contribute to the monitoring and assessment of the water quality of pond aquaculture in Chongqing,China,we conducted a monthly water quality monitoring from 10 ponds and 7 rivers at 6 sampling points（Liangping west fishing village,Liangping Xinsheng village,changshou Dai Jia xia wan,Changshou Zhang jiaqiao wan,Bishan qi long xue,and Bishan qing yun village）belonging to three districts of high agriculture production in Chongqing（i.e.Liangping,Changshou,and Bishan）,from June 2020 to April 2021.A total of 11 water quality indicators,which are required by the Fisheries administration of Chongqing city as indicators of farming strategy and aquaculture ponds tail water discharge,have been analyzed.Those parameters are water temperature,dissolved oxygen,p H,sulfide,total nitrogen,total phosphorus,ammonia nitrogen,suspended solids,COD,permanganate index and BOD.Through continuous monitoring and analysis of pond aquaculture water in 3 districts,we found that the COD peaks in ponds appear in August and September,and the valleys appear in October;the BOD valleys in ponds appear in January,February and March,July showed an upward trend,which was related to the growth of aquatic organisms in the pond,the stocking and fishing of fish,etc.;the content of TN and TP in the pond tended to be stable,and the peak time in different ponds was different,the highest value 16.58 mg/L（at pond2 of Liangping chuan west fishing）,this is related to the pollution of the water body at the time of sampling;the peak of sulfide content in the pond appears in summer,which is related to more rain in summer.According to the "Freshwater Pond Aquaculture Water Discharge Requirements",the firstlevel standard is the yellow line,and the second-level standard is the red line.The water temperature,dissolved oxygen,ammonia nitrogen,and permanganate index are not measured.The sulfide and BOD in each aquaculture pond are within the second standard;20% of the ponds with total nitrogen exceed the yellow line and 70% of the ponds exceed the red line;30% of the ponds with total phosphorus exceed the yellow line;20% of COD ponds exceed the yellow line.A comparative analysis of the ponds at 6 sampling points and the river water discharged from pond culture tail water revealed that the main water quality indicators such as TN,TP,PI,COD,BOD,and ammonia nitrogen in the ponds are all higher than those of the river.For example,in Liangping chuan West Fishing Village,the average TN content in aquaculture ponds is 8.34,which is 4.2 times that of 1.99 in the river;in Liangping Xinsheng Village,the COD in the pond is 14.36,which is 1.5 times the COD value of 9.49 in the river;in Changshou Daijiaxiawan,the TP content in the pond is 0.40,which is 2.4 times the TP content of 0.17 in the river.According to the "2018 Chongqing Environmental Statistics Annual Report",the city’s chemical oxygen demand pollution emissions were 247,800 tons.In 2018,the city’s ammonia nitrogen pollution emissions were 34,700 tons;the Chongqing Ministry of Agriculture and Rural Affairs reported that Chongqing’s intensive ponds were 400,000 mu.By calculating the average concentration according to the COD and ammonia nitrogen content of each location,CCOD=13.251mg/l,C ammonia nitrogen=1.708mg/l,and the pollution rate was evaluated.The uncorrected COD pollution rate was 3.43%,and the ammonia nitrogen pollution rate was 3.17%;the COD pollution rate was 1.92% and the ammonia nitrogen pollution rate was 1.79% after correction factor one and two;after correction factor three,i)the pollution rate of the aquaculture ponds in the city is 1.29% according to the 80% drainage volume of the pond area,and the pollution rate of ammonia nitrogen is 1.18%;ii)the pollution rate of the COD according to the 50% drainage volume of the pond area is 1.19% and the pollution rate of ammonia nitrogen is 0.75%.