摘 要:本文介绍了土壤重金属镉污染来源及对人体和植物的危害及土壤镉污染修复控制技术的研究槪况,重点概述了国内外城郊蔬菜地土壤、蔬菜重金属镉污染现状及监测评价研究进展。通过对常州市郊的前黄镇、横林镇、漕桥镇、牛塘镇、雪堰镇、魏村和湟里镇土壤及蔬菜的镉污染状况进行取样分析,研究了镉在土壤中的分布规律,以及镉在不同种类蔬菜、不同部位的积累规律,同时采用单因子指数法对检测结果进行评价。研究结果可为常州市郊蔬菜地镉污染的治理提供理论依据。主要研究结果如下:
1.常州市郊各镇土壤平均Cd浓度高低顺序为:前黄镇>湟里镇>横林镇>魏村>牛塘镇>雪堰镇>漕桥镇;土壤Cd浓度与蔬菜Cd浓度间存在一定的相关性,回归方程式为:Y蔬菜=0.2905X土壤-0.0194;R2=0.4277。
2.土壤不同深度Cd浓度的分布为:表层>15~25cm>25~35cm>35~45cm;蔬菜各部位Cd的分布特征为:根>叶>茎>果。
3.叶菜类蔬菜各部位Cd浓度分布规律为:根>叶>茎;根茎类蔬菜各部位Cd浓度分布规律为:叶>根>茎;花果类蔬菜各部位Cd浓度分布规律为:根>叶>茎>果;荚果类蔬菜各部位Cd浓度分布规律为:茎>叶>果>根。
关键词:蔬菜地;镉污染;监测;评价
Abstract:This paper introduced the sources of cadmium pollution, and its hazards to human and plants. The present situation of repair and control technology on cadmium polluted soil was briefly introduced. The present situation of heavy metal pollution in vegetables and soils in urban areas of China and abroad was reviewed, and the progress in the studies of monitor and evaluation was summarized. This article researches the distribution regularities of cadmium in the soil and the accumulation patterns of cadmium in different kinds of vegetables and in different parts of vegetables through the analysis of pollution conditions of cadmium in the soil-vegetable system in outskirts of Changzhou: Qian Huang town, Heng Lin town, Cao Qiao town, Niu Tang town, Xue Yan town, Wei Cun and Huang Li town. We also use single factor index method to evaluate the results of measurement. The results will provide important theoretical basis for the governance of cadmium pollution in vegetables in the suburb of Changzhou.
The main research results are as follows:
1. The average concentrations of Cd in the soil samples of Changzhou suburban towns were in the order:Wei Cun>Huang Li town>Xue Yan town>Cao Qiao town>Qian Huang town>Heng Lin town>Niu Tang town;Cd concentrations in soils correlated with Cd concentrations in vegetables,and the Regression equation was: Yvegetable=0.2905Xsoil-0.0194;R2=0.4277.
2. Cd concentrations in different depth of soils were:surface>15~25cm>
25~30cm>35~45cm;The distribution characteristics of Cd in different parts of vegetables were: root>leaf>stem>fruit.
3. Cd concentrations in the parts of leaf vegetables were:root>leaf>stem;Cd concentrations in the parts of root vegetables were:leaf>root>stem;Cd concentrations in the parts of fruit vegetables were:root>leaf>stem>fruit;Cd concentrations in the parts of pod vegetables were:stem>leaf>fruit>root.
Key words:Vegetable field;Cadmium pollution;Monitoring;Evaluation