中文摘要：

准确评价铜的有效性对预测长期施用有机肥土壤中铜的生态风险及其环境质量标准的修订具有十分重要意义．根据稳定性^65Cu稀释原理，利用黑麦草和蚯蚓为供试生物，对长期施用有机肥土壤中铜的同位素可交换性（E-值）、生物有效性（L-值）及pH变化对E-值、L-值的影响进行了研究．试验结果表明，以黑麦草测定的铜的L-值与铜的E-值基本相等，二者间有很高的正相关关系（R^2=0．98），不同pH处理土壤中铜的L-值占土壤全铜含量变化为15．9％-21．6％，土壤中铜的L-值、E-值随pH的上升而显著下降；而利用蚯蚓测定铜的L-值小于土壤中铜的E-值和蚯蚓肠溶物中铜的E-值；蚯蚓的活动明显增加了土壤中铜的迁移、转化特性，调节土壤pH状况可以有效控制土壤中铜的生物有效性从而降低其向食物链的迁移转化．

英文摘要：

The accurate assessment of bioavailability for copper in biosolids after its long-term application in soil is one of the key questions regarding its eco-environmental risk assessment and modifying of current soil environmental quality threshold. A procedure for determining L and E-values of Cu using ^65Cu isotopic dilution technology has been successfully developed and applied using rye grass and earthworms, the effect of pH on the L and E-values of Cu in the soils was also investigated in this study. The results indicated that the L-values determined with rye grass were nearly equal to E-values measured in soils and a good convergence of L- and E-values was observed （regression R^2=0.98）, the percentage of L-values determined with ryegrass plants of different pH treatments ranged from 15.9% to 21.6% and the measured L and E-values of Cu increased with the decreasing pH in soils; however, the L-values determined with earthworms were gen- erally less than the E-values measured in the soils and the earthworms＇ gut which indicating that the activities of worms increase the exchangeable pool of Cu in soil. The strong influence of soil pH on Cu bioavail- ability and toxicity found in this study indicated that control of soil pH is a critical factor in minimising the environmental risk of Cu from soil to food chain and ecosystem health.