汞污染对土壤有机碳稳定性和固碳功能微生物群落的影响  

Effects of Mercury Pollution on Soil Organic Carbon Stability and Carbon-fixing Microbial Communities

作　　者：张语馨 孙约兵 张仁甫 王超[1,2] 贾宏涛 ZHANG Yu-xin;SUN Yue-bing;ZHANG Ren-fu;WANG Chao;JIA Hong-tao(Xinjiang Key Laboratory of Soil and Plant Ecological Processes,College of Resources and Environment,Xinjiang Agricultural University,Urumqi 830052,China;Key Laboratory of Agro-Environmental Pollution Prevention and Control,Ministry of Agriculture and Rural Affairs,Tianjin Key Laboratory of Agro-environment and Agro-product Safety,Agro-Environmental Protection Institute,Ministry of Agriculture and Rural Affairs,Tianjin 300191,China)

机构地区：[1]新疆农业大学资源与环境学院,新疆土壤与植物生态过程重点实验室,乌鲁木齐830052 [2]农业农村部环境保护科研监测所,农业农村部产地环境污染防控重点实验室,天津市农业环境与农产品安全重点实验室,天津300191

出　　处：《环境科学》2024年第12期7358-7367,共10页Environmental Science

基　　金：中国农业科学院科技创新工程项目(CAAS-CSGLCA-202302)。

摘　　要：为阐明Hg污染对土壤有机碳稳定性及自养微生物碳同化的影响机制,采用室内培养试验与分子生物学技术,研究了Hg污染29 d前后土壤CO_(2)排放速率、有机碳组分和cbbL、cbbM功能微生物的变化特征.结果表明,不同水平Hg污染对土壤CO_(2)排放速率的影响存在差异,高水平Hg(S2、S3和S5)抑制了土壤CO_(2)累计排放量,而低水平Hg(S1、S4和S6)促进了土壤碳排放.Hg污染影响了土壤有机碳组分比例,不同处理间SOC和MBC含量变化规律基本一致,均存在显著差异(P <0.05),EOC和DOC随Hg含量的增加而降低.与第1 d相比,培养结束各处理qCO_(2)均显著降低(P <0.05).不同水平Hg污染对cbbL和cbbM功能微生物群落的影响存在明显差异,变形菌门、放线菌门和酸杆菌门是两种功能微生物共有的优势菌门.土壤CO_(2)累计排放量和SOC是影响cbbL群落变化的主要因素,土壤有效Hg是影响cbbM群落变化的主要因素.综上所述,研究结果可为Hg污染区域生态系统的碳循环及积累提供理论依据.To elucidate the effects of Hg pollution on soil organic carbon stability and autotrophic microbial carbon assimilation,the characteristics of soil CO_(2) emission rate,organic carbon components,and cbbL and cbbM functional microorganisms before and after 29 d of Hg pollution were studied using indoor culture experiments and molecular biology techniques.The results showed that the effects of different levels of Hg pollution on soil CO_(2) emission rates were different.High levels of Hg(S2,S3,and S5)inhibited soil CO_(2) cumulative emissions,whereas low levels of Hg(S1,S4,and S6)promoted soil carbon emissions.Hg pollution affected the proportion of soil organic carbon components.The changes in SOC and MBC contents in different treatments were basically the same,with significant differences(P<0.05).EOC and DOC decreased with the increase in Hg content.Compared with that at 1 d,the qCO_(2) of each treatment was significantly decreased at the end of culture(P<0.05).The effects of different levels of Hg pollution on the functional microbial communities of cbbL and cbbM were significantly different.Proteobacteria,Actinobacteria,and Acidobacteria were the dominant phyla shared by the two functional microorganisms.Cumulative soil CO_(2) emissions and SOC were the main factors affecting the change in the cbbL community,and soil available Hg was the main factor affecting the change in the cbbM community.In summary,the results of this study can provide a theoretical basis for the carbon cycle and accumulation of Hg-contaminated regional ecosystems.

关 键 词：汞污染 CO_(2)排放特征 有机碳组分 cbbL cbbM 

分 类 号：X172[环境科学与工程—环境科学] X53