Ding Yang, Huang Huan-Fang, Li Hui, Luo Jie, Zheng Huang, Sun Yan, Yang Dan, Zhang Yuan, Qi Shi-Hua
State Key Laboratory of Biogeology and Environmental Geology, School of Environmental Studies, China University of Geosciences, Wuhan 430074, China.
Guangdong Hydrogeology Battalion, Guangzhou 510510, China.
Huan Jing Ke Xue. 2017 Apr 8;38(4):1431-1441. doi: 10.13227/j.hjkx.201609019.
Mangrove wetland plays an important role in coastal environment. A total of 10 surface water samples and 7 surface sediments samples were collected in March, 2015 from Nansha mangrove wetland, and 8 compounds of organochlorine pesticides (OCPs) were determined by GC-ECD to investigate residues level, source, and ecological risk of these compounds in the study region. The result showed concentrations of OCPs in water ranged from 1.89 to 90.19 ng·L (mean 30.16 ng·L), and concentrations of OCPs in sediments varied from 3.10 to 16.02 ng·g (average 8.58 ng·g). Compared with other estuaries and harbors around the world, concentrations of OCPs in this study stayed at a median pollution level. The mean values of distribution coefficient of HCHs and DDTs between water and sediments were 857 and 368, respectively. Sediments in some parts of the area, whose distribution coefficient was relatively high, may bring water the secondary pollution. Source analysis indicated that HCHs mainly originated from the application of Lindane, and DDTs originated from mixed sources of dicofol and technical DDT. Compared with OCPs in water, OCPs in sediments might contain more historical residual components. OCPs in water had light ecological risk, but OCPs in sediments posed a potential high risk to mangrove ecosystem.
红树林湿地在海岸环境中发挥着重要作用。2015年3月，从南沙红树林湿地采集了10个地表水样本和7个表层沉积物样本，采用气相色谱 - 电子捕获检测器测定了8种有机氯农药（OCPs），以研究该研究区域内这些化合物的残留水平、来源及生态风险。结果表明，水中OCPs浓度范围为1.89至90.19 ng·L（平均30.16 ng·L），沉积物中OCPs浓度在3.10至16.02 ng·g之间（平均8.58 ng·g）。与世界其他河口和港口相比，本研究中OCPs浓度处于中等污染水平。六六六（HCHs）和滴滴涕（DDTs）在水和沉积物之间的分配系数平均值分别为857和368。该区域部分地区的沉积物分配系数相对较高，可能会给水体带来二次污染。来源分析表明，HCHs主要来源于林丹的使用，DDTs来源于三氯杀螨醇和工业用DDT的混合源。与水中的OCPs相比，沉积物中的OCPs可能含有更多的历史残留成分。水中的OCPs具有较轻的生态风险，但沉积物中的OCPs对红树林生态系统构成潜在的高风险。
