东江流域突发水污染风险分区研究

东江流域突发水污染事故频发,对区域人群健康和生态安全造成严峻挑战。环境风险分区是环境风险管理的基础和有效工具。以2015年为基准年,基于环境统计数据、DEM数据、水质监测断面数据和基础地理数据,引入地理信息系统空间分析法、区域生长法,综合考虑了水系流向、水系级别及水质等因素,以1 km×1 km的网格为基本单元,对东江流域开展突发水污染风险分区。结果表明:(1)高风险区面积为696.7 km~2,占评估区总面积的1.99%;较高风险区面积为1458.4 km~2,占比4.17%;中风险区面积为2762.0 km~2,占比7.90%;低风险区面积为30031.7 km~2,占比85.93%;(2)从各子流域平均风险值来看,石马河流域风险最高,其次为淡水河流域、公庄水流域;(3)从沿东江干流两岸分布来看,高风险区面积沿东江上游至下游呈逐渐增加趋势,主要集中分布在龙川县、博罗县、东莞市、深圳市等地;从沿东江主要支流两岸分布来看,高风险区主要分布在惠州市、深圳市等地。研究结果可为东江流域生态环境管理提供理论支撑。

Risk zoning of sudden water pollution in Dongjiang River basin

The frequent occurrence of sudden water pollution accidents in the Dongjiang River basin poses severe challenges to the human health and ecological security of the regional population. Environmental Risk Zoning is a fundamental and effective tool for environmental risk management. Based on the Annual Environmental Statistics Yearbook, DEM, National Water Quality Monitoring Data and basic geographical data, and by adopting the spatial analysis method of Geographic Information System and Regional Growth Method, the paper zoned and classified the risk of water environment at a grid map of Dongjiang River basin with the resolution of 1 km×1 km. The results show that (1) the high-risk area is 696.7 km², accounting for 1.99% of the total assessed area. The relatively high-risk area is 1458.4 km², accounting for 4.17%. The middle-risk area is 2762.0 km², accounting for 7.90%. The low-risk area is 30031.7 km², accounting for 85.93%. (2) According to average risk value, the Shima river basin has the highest risk, followed by Tamsui river basin and Gongzhuang river basin. (3) From the mainstream distributional perspective, the area of high risk areas increases gradually from the upstream to the downstream of the Dongjiang River, mainly distributed in Longchuan county, Boluo county, Dongguan city, Shenzhen and other places. From the tributaries distributional perspective, the high risk areas are mainly distributed in Huizhou, Shenzhen and other places. The research results can provide theoretical and technical support for ecological and environmental management of Dongjiang River basin.