中文摘要：

南渡江流域新坡河塘疏浚底泥的利用方向规划为农田土地整治工程中耕作层的替代土,用来发展蔬菜种植业.为了探清该流域河塘疏浚底泥的养分水平及重金属污染状况,综合考虑河塘的形态、水域面积、断面特征、流速、底泥沉积量采取典型断面布设和网格法布点,将所调查的河塘分为上游和下游,共采集0~40 cm 深的底泥样品78个.通过室内底泥样品成分检测、养分灰色关联度评价、内梅罗综合污染评价、GIS 空间分析等方法,分析和评价了河塘底泥的养分特征、肥力水平、重金属的含量、污染程度及空间格局分布特征,掌握了该流域底泥的养分条件、底泥重金属污染状况及底泥农业利用的风险.结果表明：1）底泥的全氮、全磷、全钾及有机质含量呈现空间异质性,下游的全氮、全磷均值含量较上游分别高出32.45%、11.88%,而下游的全钾、有机质均值含量较上游分别低14.64%、14.62%,上游段底泥养分数据的变异系数普遍高于下游段,底泥养分异质性是由河流流速、周边的自然环境及人为耕作活动造成.底泥中的全氮、全磷、有机质等养分指标达到1级（丰）水平,统计分析全钾含量为5级（缺）水平;整个河塘底泥养分要高于对照点,为底泥的农业土地利用提供了有利条件.2）底泥重金属污染物主要为 Cd 和 Cu,其次为和 Cr 和 Ni,Cd、Cu、Cr、Ni 样品单因素污染超标率分别为76.92%、47.44%、56.41%、23.07%,且超标幅度分别为58.45%、104.58%、6.06%、68.48%;底泥重金属污染是因基性火山岩为成土母质,背景值偏高,土壤重金属被酸雨淋溶出,并随地表径流汇集在河塘中,造成了底泥的重金属超标.内梅罗综合污染指数评价可知河塘底泥是以轻微污染和中度污染为主,分别占样品数的46.15%、28.21%;底泥污染状况具有明显的空间异质性,轻微污染水平（3级）和中度污染水平（4级）的区域面积?

英文摘要：

Sediment, the major reservoir of contaminants in a lake, contains not only hazardous matter, but also nutrients like nitrogen, phosphorus, and organic matter. So the detoxification, recycling and reuse of sediment has been widely studied. Agricultural land use of sediment is a potentially feasible approach for contaminated site remediation and can achieve good economic and environmental benefits. The key concept is to control the pollutant content and soil burden according to the related environmental standards. Heavy metals reserved in agricultural soil would greatly affect the grain yield and quality, as well as food safety, and are one of the major environmental pollution sources threatening human health. In this article, the sediment content in Xinpo Pond of the Nandu River Valley was planned to be used as the substitute soil of plough horizon in farmland remediation engineering to develop vegetable farming. To investigate the nutrient content and the degree of heavy metal contamination of the pond sediment, the shape and dimension of the pond, characteristics of the cross-section, flow rate, and the amount of sediment were comprehensively explored. Typical cross-section and grid sampling methods were chosen to collect samples within the 0~40 cm depth of the sediment. Based on （a） farmland environmental quality evaluation standards for edible agricultural products as the heavy metals evaluation criteria and （b） the second national soil survey classification criteria as the nutrient evaluation criteria, adopting sample testing, statistical analysis, nutrients gray correlation analysis, Nemerow pollution index assessment and GIS spatial analysis, the nutrient characteristics, soil fertility, heavy metal content, pollution degree and spatial distribution of the pond sediment were analyzed. The results showed： 1） Total nitrogen, total phosphorus, total potassium and organic matter content of the sediment presented spatial heterogeneity. Sediment total nitrogen content was in the range of 0.1300 ~ 6.76