Su Qian-Qian, Li Lian-Fang, Zhu Chang-Xiong, Ye Jing, Liu Xue, Geng Bing, Tian Yun-Long, Huang Xiao-Ya
Key Laboratory of Agro-Environment, Ministry of Agriculture and Rural Affairs, Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Huan Jing Ke Xue. 2022 Mar 8;43(3):1630-1640. doi: 10.13227/j.hjkx.202106028.
Cerium-manganese modified biochar (MBC) combined with earthworms ( can immobilize arsenic (As) in red soils. In this study, high-throughput sequencing technology was used to explore the combined effects of MBC and on bacterial diversity and community structure in As-contaminated red soils. The results showed that the single earthworm treatment had the highest diversity index, whereas the diversity index decreased in the single biochar or MBC treatment, indicating that earthworms can boost the growth of bacteria in the soil, and the addition of biochar/MBC all decreased the bacterial diversity of soils. When biochar/MBC was combined with earthworms, the diversity index increased to some degree. In terms of bacterial community structure, the relative abundance of Proteobacteria and Bacteroidetes increased significantly in each treatment, especially for MBC-earthworm treated soil, in which the relative abundance was increased by 17.08% and 329.47% for Proteobacteria and Bacteroidetes, respectively, compared to that in the control (CK). Otherwise, those abundances were decreased by 19.18% and 48.76%, respectively, for Acidobacteria and Chloroflexi. Correlation analysis results showed that the soil water-soluble As (WSAs) was negatively correlated with the relative abundances of Proteobacteria and Bacteroides (<0.05) but was positively correlated with Acidobacteria and Chloroflexi (<0.05), which indicated that with the decrease in WSAs in soils, the bacteria of Proteobacteria and Bacteroides reproduced rapidly, whereas the Acidobacteria and Chloroflexi were inhibited. Moreover, different treatments induced selective changes in the bacterial community, in which earthworms significantly promoted the proliferation of -Proteobacteria, Flavobacteriales, Aeromonadales, and and earthworms improved the immobilization effect of As by promoting the growth of these bacteria.
铈锰改性生物炭（MBC）与蚯蚓联合使用可固定红壤中的砷（As）。本研究采用高通量测序技术，探讨了MBC与蚯蚓联合作用对As污染红壤细菌多样性和群落结构的影响。结果表明，单一蚯蚓处理的多样性指数最高，而单一生物炭或MBC处理的多样性指数降低，这表明蚯蚓可促进土壤中细菌的生长，而生物炭/MBC的添加均降低了土壤细菌多样性。当生物炭/MBC与蚯蚓联合使用时，多样性指数有一定程度的增加。在细菌群落结构方面，各处理中变形菌门和拟杆菌门的相对丰度显著增加，尤其是MBC-蚯蚓处理的土壤，与对照（CK）相比，变形菌门和拟杆菌门的相对丰度分别增加了17.08%和329.47%。此外，酸杆菌门和绿弯菌门的丰度分别下降了19.18%和48.76%。相关性分析结果表明，土壤水溶性As（WSAs）与变形菌门和拟杆菌门的相对丰度呈负相关（<0.05），但与酸杆菌门和绿弯菌门呈正相关（<0.05），这表明随着土壤中WSAs的减少，变形菌门和拟杆菌门的细菌迅速繁殖，而酸杆菌门和绿弯菌门受到抑制。此外，不同处理诱导了细菌群落的选择性变化，其中蚯蚓显著促进了β-变形菌纲、黄杆菌目、气单胞菌目等的增殖，蚯蚓通过促进这些细菌的生长提高了As的固定效果。
