为探究巯基坡缕石对镉（Cd）–砷（As）复合污染土壤的修复效果及其对土壤生态功能的影响，以Cd-As复合污染水稻土为研究对象，探究了1%、2%巯基坡缕石添加对土壤理化性质、Cd和As有效态的影响，并采用高通量测序技术分析了不同处理对土壤微生物群落结构的影响。结果表明：巯基坡缕石添加显著降低了土壤pH，其中2%处理下pH降低更明显。与对照相比，1%和2%巯基坡缕石处理下，土壤有机质含量分别增加了30.2%、60.9%，Cd的有效态含量与毒性特性浸出量分别降低了97.7%~98.3%、77.1%~92.7%，而As的有效性未发生显著变化。巯基坡缕石添加对土壤微生物多样性及丰度无显著影响，但属水平下Pseudanabaena_NgrPSln22和Pseudomonas的相对丰度显著降低了85.4%~98.1%、75.3%~78.9%。巯基坡缕石处理下土壤微生物群落结构显著改变，其中pH和Cd的有效性是显著影响因素。总之，巯基坡缕石不仅能显著降低Cd有效性，提高土壤有机质含量，还会影响细菌群落结构，增加土壤抗病菌丰度和减少固氮菌丰度。

To explore the remediation effects of mercaptopalygorskite on cadmium (Cd)-arsenic (As) co-contaminated soil and its microbial community, in this study, 1% and 2% mercaptopalygorskite were applied to Cd-As co-contaminated paddy soil to explore their effects on soil properties, the availabilities of Cd and As. High-throughput sequencing technology was also used to explore the effect of mercaptopalygorskite on microbial community. The results showed that the addition of mercaptopalygorskite significantly reduced soil pH, and the effect was more obvious under 2% mercaptopalygorskite treatment. Compared with the control, soil organic matter contents increased significantly by 30.2% and 60.9% under 1% and 2% mercaptopalygorskite treatments, respectively, the concentration of available Cd and toxicity characteristic leaching procedure (TCLP) of Cd reduced by 97.7%-98.3% and 77.1%-92.7% under 1% and 2% mercaptopalygorskite treatments, respectively. Whereas the concentration of available As changed insignificantly. Furthermore, the addition of mercaptopalygorskite had no significant effect on soil microbial diversity and richness, however, the relative abundance of Pseudanabaena_NgrPSln22 and Pseudomonas genuses decreased by 85.4%-98.1% and 75.3%-78.9%, respectively. Mercaptopalygorskite addition significantly altered soil microbial community structure, with pH and Cd availability being the main factors affecting microbial community structure. In conclusion, mercaptopalygorskite can not only significantly reduce the availability of Cd and promote soil organic matter content, but also impact soil microbial community structure and increase the abundance of disease-resistant bacteria and reduce the abundance of azotobacter.

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国家自然科学基金项目（42107017）和成都市科技项目（2020-YF09-00023-SN和2020-YF09-00012-SN）资助。