中国近海入境船舶压舱水输入特征与风险分析

Input characteristics and risk analysis of ballast water in entry ships at China's offshore sea area

远洋船舶压舱水在我国港口海域的大量排放是造成地理性隔离水体间外来海洋有害生物传播和近岸海域环境日益恶化、赤潮灾害频发的重要因素之一。基于中国港口入境船舶压舱水输入总量估算模型,通过调查国家交通运输部和国家海关总署公开发布的外贸航运及商品进出口信息,在确立中国港口入境船舶压舱水输入总量和中国五大港口群体压舱水输入比值的基础上,分析了2007年至2012年中国近海入境船舶压舱水的输入特征和环境生态风险。结果表明:我国五大港口群体入境船舶压舱水的输入总量极不平衡,经济最发达的长江三角洲区域输入的境外压舱水总量最多,2012年输入量为10 368万t,其次是环渤海地区,为7 371万t,珠江三角洲地区排第三位,为6 729万t,东南沿海地区和西南沿海地区输入的压舱水总量较少,仅有1 659万t和571万t。入境船舶压舱水的大量排放对我国尤其是经济发达区域的港口海域生态环境构成了巨大的威胁。

A great volume of ballast water discharge from ocean ships in the sea area of Chinese ports is one of the important factors which cause the spread of aquatic nonindigenous harmful species isolated geographically by waters, the environmental deterioration of the nearshore water area and the frequent outbreaks of red tides. In this paper, the total amount of the ballast water input estimation model for entry ships in Chinese ports was established. The information of foreign trade shipping and the import and export goods released publicly by the State Department of Transportation and the State General Administration of Customs were investigated. And then, the input features and its ecological environment risk of ballast water in entry ships at China＇s offshore sea areafrom 2007 to 2012 were analyzed based on the established total input amount of ballast water from entry ships to Chinese sea ports together with the ballast water input ratio of the five major portgroups in China. The results show that the total ballast water input amounts from entry ships of the five major port-groups in China are extremely unbalanced. The most developed Yangtze River Delta has the biggest ballast water input amount,103.61 million tons in 2012. The second is the Circum-Bohai sea area（73.66 million tons） and the third is the Pearl River Delta（67.24 million tons）. The total ballast water input amounts of the northwest and the southwest coastal areas are less,only 16.57 and 5.71 million tons respectively. The large amount of ballast water discharge from entry ships has been an enormous threat to the ecological environment of sea areas in China, especially to the economically developed regions.