This study investigated the passivation of multiple heavy metals (Cd, Cr, Cu, Zn, and Pb) in river sediments by composting with rice straw. The correlation between the selected environmental factors and the distribution of heavy metal fractions was assessed by multivariate analysis. The results suggested that the composting could reduce the bioavailability of Cu, Cd, Cr, and Pb. The influences of composting on the passivation of these five heavy metals are different. The greatest passivation of heavy metals is for Cd, which its bioavailability decreased 17.72%. The bioavailability of Cu, Pb, and Cr also partly decreased. However, there was almost no effect on the bioavailability of Zn. The results of multivariate analysis revealed that the predominant parameters affecting the variation of the bioavailability of different heavy metals were different in a complex composting system with multiple heavy metal pollution. While the variation partitioning analysis indicated that water-soluble carbon (WSC) was the statistically main factor affecting the bioavailability of Cd, Cr, Cu, Zn, and Pb. It provides a theoretical reference for optimizing the co-composting process in remediation of different heavy metal contamination in sediments.

本研究通过稻草堆肥研究了河流沉积物中多种重金属（Cd，Cr，Cu，Zn和Pb）的钝化。通过多变量分析评估所选环境因素与重金属组分分布之间的相关性。结果表明，堆肥会降低铜，镉，铬和铅的生物利用度。堆肥对这五种重金属钝化的影响是不同的。重金属的最大钝化作用是镉，其生物利​​用度下降了17.72％。Cu，Pb和Cr的生物利用度也部分降低。但是，对锌的生物利用度几乎没有影响。多元分析结果表明，在具有多种重金属污染的复杂堆肥系统中，影响不同重金属生物利用度变化的主要参数是不同的。虽然变异划分分析表明水溶性碳（WSC）是影响Cd，Cr，Cu，Zn和Pb生物利用度的统计学主要因素。它为优化共沉淀过程在沉积物中不同重金属污染的修复提供了理论参考。