污染场地中有机氯农药对土壤原生动物群的影响

有机氯农药污染土壤对生态环境具有潜在的风险。采集某废弃农药厂污染场地的土壤样品,测定了土壤的理化性质,以及典型有机氯农药滴滴涕(DDTs)和六六六(HCHs)的残留浓度,并对土壤中原生动物的组成和数量进行了分析。结果显示,农药厂区域的土壤中原生动物的组成结构为:鞭毛虫和肉足虫为优势类群,纤毛虫为稀有类群。土壤理化性质与原生动物数量的相关性分析表明,总氮含量与鞭毛虫、纤毛虫数量和原生动物总数量呈显著正相关,总磷含量与肉足虫数量呈显著正相关。同时,农药厂区域土壤中的原生动物数量较对照区显著减少,污染场地中长期残留的有机氯农药对原生动物有明显抑制作用。

Effects of Organic Chlorine Pesticide in Contaminated Sites on Soil Protozoa Community

The organic chlorine pesticide contaminated soil has potential risks to ecologic environment. It is necessary to study ecological effects of the protozoa caused by the organic chlorine pesticide. The basic physical and chemical properties of the collected soils from an abandoned pesticide plant were measured. Meanwhile, the residue concentrations of DDTs and HCHs were assessed. The community structure and abundance of the protozoa in the soil samples were analyzed. The experiments revealed that the dominant species of the three groups of the protozoa was flagellate, while ciliate was the rare species. The correlation analysis between the basic physical and chemical properties of the soils and the abundance of soil protozoa indicated that total nitrogen was significantly positive correlated with the abundance of flagellate, ciliate and soil protozoa. Total phosphorus only significantly affected the abundance of sarcodina. The abundance of soil protozoa in the contaminated soil samples was significantly lower than those in the control soils, suggesting that the long-term residue of organic chlorine pesticides in soils decreased the abundance of the soil protozoa.