Li Xin-Yan, Li Heng-Peng, Jiang San-Yuan, Ma Pei, Lai Xi-Jun, Deng Jian-Cai, Chen Dong-Qiang, Geng Jian-Wei
Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China.
Schools of Resources and Environmental Engineering, Henan Institute of Engineering, Zhengzhou 451191, China.
Huan Jing Ke Xue. 2020 Sep 8;41(9):4042-4052. doi: 10.13227/j.hjkx.201912201.
Eutrophication of shallow lakes in the middle and lower reaches of the Yangtze River has become an increasingly serious problem. In this study, we investigated the temporal and spatial variations in nutrient loads (nitrogen, N and phosphorus, P) in the Changdang Lake Catchment located to the northwest of Lake Taihu through field sampling and laboratory analysis in 2016-2017. The results show the severity of the N and P pollution in the Changdang Lake catchment. The mean river water concentrations of TN, NO-N, NH-N, TP, Chla, and permanganate index are (3.70±0.76) mg ·L, (1.81±0.42) mg ·L, (1.03±0.61) mg ·L, (0.38±0.31) mg ·L, (25.74±37.00) μg ·L, and (6.35±0.81) mg ·L, respectively. N pollution in the river is more severe in winter and spring than in summer and autumn whereas P pollution in the river is worse in autumn and winter than in spring and summer. Spatially, the magnitude of river N and P pollution follows the order of northern > northwestern > southern > eastern part of the study area. The rivers are in a state of moderate to severe eutrophication. The mean lake water concentrations of TN, NO-N, NH-N, TP, Chla, and permanganate index are (2.25±0.94) mg ·L, (0.98±0.47) mg ·L, (0.19±0.14) mg ·L, (0.11±0.03) mg ·L, (18.71±8.76) μg ·L, and (4.59±1.09) mg ·L, respectively. The water quality in Changdang Lake is categorized as worse than class Ⅲ for TN and TP concentrations, which show decreasing trends from the west to the east to the south of the lake. The lake is in a status of slight to moderate eutrophication. The lake water quality is affected by the combination of sewage discharge and non-point source pollutant losses. The inflow rivers including the Danjinlicao River, Tongji River, and Xuebu River are the dominant pollution sources for Changdang Lake. The Danjinlicao River transports 10-12 times the total N and P loads transported by Tongji and Xuebu rivers. Changes in land use and atmospheric deposition are the driving factors of the deterioration of water quality and eutrophication in the catchment.
长江中下游浅水湖泊的富营养化已成为一个日益严重的问题。在本研究中，我们于2016 - 2017年通过实地采样和实验室分析，调查了位于太湖西北部的长荡湖流域营养负荷（氮、N和磷、P）的时空变化。结果显示了长荡湖流域氮和磷污染的严重程度。河水总氮（TN）、硝态氮（NO₃-N）、氨氮（NH₃-N）、总磷（TP）、叶绿素a（Chla）和高锰酸盐指数的平均浓度分别为（3.70±0.76）mg·L、（1.81±0.42）mg·L、（1.03±0.61）mg·L、（0.38±0.31）mg·L、（25.74±37.00）μg·L和（6.35±0.81）mg·L。河流中的氮污染在冬季和春季比夏季和秋季更严重，而磷污染在秋季和冬季比春季和夏季更严重。在空间上，河流氮和磷污染的程度遵循研究区域北部＞西北部＞南部＞东部的顺序。河流处于中度至重度富营养化状态。湖水TN、NO₃-N、NH₃-N、TP、Chla和高锰酸盐指数的平均浓度分别为（2.25±0.94）mg·L、（0.98±0.47）mg·L、（0.19±0.14）mg·L、（0.11±{此处原文有误，推测应为0.03}）mg·L、（18.71±8.76）μg·L和（4.59±1.09）mg·L。长荡湖的水质因TN和TP浓度而被归类为劣于Ⅲ类，从湖泊西部到东部再到南部呈现下降趋势。湖泊处于轻度至中度富营养化状态。湖泊水质受到污水排放和非点源污染物损失的共同影响。包括丹金溧漕河、通济河和薛埠河在内的入湖河流是长荡湖的主要污染源。丹金溧漕河输送的总氮和总磷负荷是通济河和薛埠河的10 - 12倍。土地利用变化和大气沉降是流域水质恶化和富营养化的驱动因素。
