土壤整体质量的生态毒性评价

土壤样品采自沈阳西部污灌区 .进行了污染物 (重金属和矿物油 )含量分析和生态毒性试验 .重金属采用原子吸收分光光度仪测定 ,矿物油采用紫外分光光度计测定 .生态毒性试验分别参照国际标准组织 (ISO)和OECD指南 ,进行了植物毒性试验、蚯蚓毒性试验和蚕豆根尖微核试验 .植物试验以小麦种子发芽根伸长抑制率为试验终点 ,试验周期50h ,蚯蚓毒性试验以蚯蚓死亡率、体重增长抑制率为试验终点 ,试验周期28d .土壤中矿物油含量在145mg/kg～1121mg/kg ,重金属Cd为0.34mg/kg～1.81mg/kg .土壤对植物和蚯蚓显示不同程度的毒性效应 ,土壤的蚕豆根尖微核率明显高于对照 .种子发芽根伸长抑制率为2.0%至-35.1% ,蚯蚓死亡率为0%～40%.体重增长抑制率由14d的-2.3%～-19.4%在28d增加到-2.1%～10.7% ,蚕豆根尖微核率最高达6.62/100.研究表明 ,土壤中的污染物积累较低 ,但具有明显的生态毒性 .

Evaluation of Eco-Toxicity of Integral Quality of Soils

Soil samples are collected from several sites along the wastewater irrigation channel, western Shenyang. The concentration of heavy metal(Cd)and mineral oil is analyzed. The eco-toxicity of soil is evaluated. Heavy metal (Cd) isdetermined by atom adsorption spectrometer(AAS), mineral oil is measured by UV spectrometer. The eco-toxicity of soil is based on the method of international standardization of organization (ISO) and OECD guideline with some modification. With inhibition rates of root elongation of wheat as endpoint seed germination test was performed and the duration period was 50h. With lethal and sub-lethal effects as endpoint earthworms test was conducted and the experimental period was 28d. And micronuclear( MCN) test was conducted. Results show the mineral oil in soils were 145 mg/kg - 1 121mg/kg, Cd was 0.34mg/kg - 1.81mg/kg. The inhibition rate of root elongation based on germination test was 2.0% - 35.1%, MCN in soil was significant higher than that in the control. The mortality rates of earworms were 0% - 40%. The inhibition rates of body weight growth were -2.3 % to -19.4% from 14d to -2.1% - 10.7% in 28d. The maximum value of MCN in soils was 6.62/100. The study indicates a lower accumulation of pollutants in soils but enhanced ecotoxicity.