针对土壤重金属修复需求，选取最重要土著微生物SRBs，以阴离子形式存在具有类似性质不同转化要求Cr(VI)和As(III)复合污染土壤为研究对象，采用土壤化学、微生物学、生物化学与分子生物学、化学计量学、数学分析方法围绕土壤中SRBs转化重金属途径及机理这一科学问题，重点研究以下内容：（1）调查典型污染土壤SRBs的时空分布规律，厘清土壤中参与Cr和As转化的主要功能SRBs物种组成规律及与土壤各因子的相关性；（2）建立不同电子供体-Cr和As复合污染土壤-优势SRBs微宇宙模拟实验体系研究电子供体及其他关键限制因子对SRBs转化Cr(VI )和As(III)途径的影响机制；（3）探讨SRBs对Cr(VI)的还原与As(III)氧化的协同转化的可能性。预期结果对于明确土壤SRBs优势功能菌的转化重金属的驱动和调控机制，为强化土著SRBs原位修复复合重金属污染土壤的治理提供理论和技术支持。

In order to meet the needs of remediation of heavy metals in soil, the most important indigenous microorganism, SRBs, will be selected..Cr (VI) and As (III) in the contaminated soil are studied in the form of anions with similar properties for different transformational requirements. Scientific Issues on the Pathway and Mechanism of Heavy Metals Transformation by SRBs in Soil using Soil Chemistry, Microbiology, Biochemistry and Molecular Biology, Stoichiometry and Mathematical Analysis Methods.The main research contents are as follows:.(1).To investigate the spatio-temporal distribution of SRBs in typical polluted soil, and to clarify the species composition of SRBs which are involved in the transformation of Cr and As, and the correlation between SRBs and soil factors;.(2). The effects of electron donors and other key limiting factors on the Cr (VI) and As (III) pathway are studied by establishing the micro-cosmological simulation experiment system of different electron donors-Cr and As compound polluted soil-dominant SRBs;.(3).The possibility of synergistic transformation of reduction of Cr (VI) and oxidation of As (III) was discussed. The results are expected to clarify the driving and regulating mechanism of heavy metals transformation in SRBs-dominant bacteria, and to provide theoretical and technical support for the in-situ remediation of heavy metals-contaminated soil by indigenous SRBs.