广西北部湾经济区重点海湾水污染物特征分析

Analysis on Water Pollutant Characteristics of Key Bays in Guangxi Beibu Gulf Economic Zone

陆源污染是海洋环境污染的最主要来源。海湾汇水区水污染物排放研究对海湾绿色发展意义重大。通过环境污染综合评价、聚类分析研究了广西北部湾经济区重点海湾汇水区水污染物的排放现状、结构特征、分布规律。结果表明生活源和农业源是重点海湾汇水区水污染物最主要来源。廉州湾和茅尾海的水污染物排放量占整个研究区总排放量近七成,钦州湾工业源排放占比较高。各海湾的水污染物排放强度特征呈现明显分层现象。城镇化、工业化相对发达的海湾区域的主要污染物排放强度明显低于城镇化、工业化较低、农业占比较大的湾区。在推进海湾地区绿色发展的过程中,需加强畜禽养殖污染、水产养殖污染和农村污水污染治理,注重工业产业结构和产品结构升级和绿色转型,合理规划控制城镇扩张,科学推进深海排放,提升环境承载力以缓解环境压力。

Land-based pollution is the main source of marine environmental pollution.Research on the water pollutant emissions in catchment area of a gulf is crucial for the green development of the gulf.This paper studied the current status,structural characteristics,and spatial distribution of water pollutant emissions in the catchment areas of key bays in Guangxi Beibu Gulf Economic Zone through comprehensive assessment and clustering analysis on water pollutant emissions.The results showed that the agricultural and domestic discharges were the main sources of water pollutants in the catchment areas of the Gulf.The water pollutant emissions of Lianzhou Bay and Maowei Sea accounted for nearly 70%of the total emissions of the entire research area,and the industrial emissions of the Qizhou Bay accounted for a higher proportion.The water pollutant emission intensity of each bay showed obvious stratification.The emission intensity of main pollutants in the bay area with higher urbanization rate and more developed industry was significantly lower than that in the bay area with lower urbanization rate and larger agricultural proportion.Therefore,except for strengthening the governance of livestock and poultry breeding pollution,aquaculture pollution and rural sewage,we should also pay attention to upgrade the industrial structure,product structure and green transformation,reasonably plan and control urban expansion,scientifically promote deep-sea discharge,and enhance the environmental carrying capacity to alleviate environmental pressure.