佛山市郊菜地土壤理化性质与重金属含量及其相关性

Study on Physical-chemical Properties and Contents of Heavy Metals and Their Correlation in Vegetable Fields of Foshan

对佛山市郊主要菜地土壤理化性质与重金属污染状况及其之间的相关性进行分析。结果表明:菜地土壤呈酸性,有机质含量偏低,而碱解氮、速效磷和速效钾含量普遍较高。Cd平均含量超出国家土壤环境质量二级标准,但Cu、Zn、Ni、Pb、Cr平均含量都在国家二级标准内,Cd是主要污染因子。pH与速效磷、碱解氮、速效钾存在极显著或显著负相关关系;碱解氮、速效磷和速效钾三者之间均存在极显著正相关关系;Cu、Zn、Ni、Pb和Cr之间存在极显著或显著正相关关系,它们具有同源关系,并呈现复合污染的趋势;pH与Cu、Zn、Ni、Cr、Cd呈正相关;有机质与Cu、Zn、Pb、Cr表现出中等正相关;碱解氮、速效磷、速效钾与所有重金属都呈负相关,但相关性不显著。

This paper analyzed the physical - chemical properties and pollution of heavy metal in soils of main vegetable fields in the suburb of Foshan, as well as their correlations. The results showed that the soils of vegetable fields were acid and the con- tents of organic matter were low, while those of alkali dispelled nitrogen, and available phosphorus and available potassium were high generally. The average contents of Cd exceeded the National Secondary Standard for soil environment quality, but those of Cu, Zn, Ni, Pb and Cr were within the National Secondary Standard. Cd was the main pollution factor. Very remarkable or re- markable negative correlated relation was found between pH and alkali dispelled nitrogen, available phosphorus, available potassi- um; very remarkable positive correlated relation among alkali dispelled nitrogen, available phosphorus and available potassium; very remarkable or remarkable positive correlated relation among Cu, Zn, Ni, Pb and Cr which came from the same source and tended to pollute; positive correlation between pH and Cu, Zn, Ni, Cr, Cd and middle positive correlation between organic matter and Cu, Zn, Pb, Cr; negative correlation among alkali dispelled nitrogen, available phosphorus, available potassium and all the heavy metals, but the correlation was not remarkable.