南汇咀～嵊泗海域水体重金属元素分布及其污染评价

该文根据１９９５年１０月水质调查资料，阐明了南汇咀～嵊泗海域重金属元素［］西高东低、底高表低的分布势态，其分布势态取决于径流、湾水、流场、污染源、输沙量和锋面的综合作用。对泥沙在水中的理化性质分析揭示：细颗粒（ｄ＜６３μ）悬沙的吸附和解吸特性是重金属元素和悬沙间具有正相关的内在原因，置换吸附是重金属元素间具有互相关的重要因素之一。通过模糊理论水质综合评价得：该水域上层属Ⅰ级海水，中层属Ⅰ级或Ⅱ级海水，均未受重金属元素污染；底层除二个站受轻度和中度污染外，大致可划分为东、中、西三个水域，东部为Ⅰ级海水，中部为Ⅱ级海水，西部已受重金元素微污染、为Ⅲ级海水。

Distribution and Pollution-evaluation of Heavy-metal Element in the Water Field from the Nanhui Spit to the Chensi Island

Based on the water quality survey October, 1995, the paper revealed that the content of heavy mental elements in the studied field was higher in the west than in the east and higher on the bottom than on the surface. This distribution law depends on the comprehension of river discharge, tidal current field, the source of pollution, sediment transportation and estuarine front. The analysis of physical and chemical characteristics of sediments in the water showed: the process of absorption and desorption of the suspended fine sediments (d<63u) was the basic cause of the positive correlation among heavy metal elements. Comprehenive evaluation through fuzzy theory showed: (a) The upper water belonged to lst grade while the middle water belonged to lst or 2nd grade, both were not polluted by heavy metals. (b) The bottom water belonged to the lst grade in the east, 2nd grade in the center and 3nd grade in the west(polluter for a little by heavy metals).