摘要
总结了几种具有重金属耐性的微生物及耐性机制,并分析了微生物群落在重金属污染土壤修复过程中的作用。微生物主要以2种方式强化植物对重金属污染土壤的修复效果:一是微生物对重金属具有吸附作用,减轻土壤中重金属对植物的毒害;二是分泌有机酸及植物生长所需的营养物质促进超富集植物对重金属的吸收。耐受重金属的微生物主要以细菌居多,可能是因为细菌对环境具有更强的适应能力,在极端环境胁迫下具有更完善的抗性机制。微生物对重金属具有耐性是因为微生物可以分泌螯合剂与重金属生成螯合物,或通过铁载体络合作用等途径降低重金属的生物毒性,减轻重金属对微生物的危害。微生物对重金属污染土壤的修复具有显著影响,所以在修复过程中可以强化微生物功能。要重点研究根际微生物、根系和介质载体三者之间复合功能,结合污染土壤类型与植物群落配置的特点筛选耐受或吸附重金属的菌种和菌群。
Several heavy metal-tolerant microorganisms and their tolerant mechanisms were summarized,and the role of microbial communities in the process of heavy metal contaminated soil remediation was analyzed.The repairing effects of plants on heavy metal contaminated soils was mainly strengthened by microorganisms in two ways.In one way,microorganisms could absorb heavy metals and relieve the toxicity of heavy metals in soil to plants.In the other way,microorganisms could secrete organic acids and nutrients needed in plants growth to promote the absorption of heavy metals by hyperaccumulators.Most of the heavy metal-tolerant microorganisms were bacteria,the reason may be that bacteria have stronger adaptability to the environment and have more perfect resistant mechanism under extreme environmental stresses.Microorganisms were resistant to heavy metals because they can secrete chelating agents to form chelates with heavy metals,or reduce the biotoxicity of heavy metals by means of iron carrier complexation,and reduce the harm of heavy metals to microorganisms.Microorganisms had a significant impact on the repair of heavy metal contaminated soils,so the function of microorganisms could be enhanced during the process of repair.The composite functions between rhizosphere microorganisms,roots and media carriers should be studied with focus,and the microbial strains and floras that can tolerate or adsorb heavy metals can be screened by comprehensive consideration of the contaminated soil types with the allocation features of plant communities.
作者
杨雍康
药栋
李博
李明锐
湛方栋
祖艳群
李元
YANG Yong-kang;YAO Dong;LI Bo;LI Ming-rui;ZHAN Fang-dong;ZU Yan-qun;LI Yuan(College of Resources and Environment,Yunnan Agricultural University,Kunming 650201,China)
出处
《江苏农业学报》
CSCD
北大核心
2020年第5期1322-1331,共10页
Jiangsu Journal of Agricultural Sciences
基金
云南省重点研发计划项目(2018BB017)
云南省重点研发计划课题(2019BC001-04)
云南省农田无公害生产创新团队项目(2017HC015)。
关键词
土壤
重金属污染
微生物
重金属耐性
soil
heavy metal contamination
microorganism
heavy metal tolerance
