摘要
填埋场覆土中的甲烷氧化菌可削弱填埋场的温室气体释放,其中Ⅰ型甲烷氧化菌对环境条件的改变反应灵敏.实验采用16SrDNA特异性聚合酶链式反应(polymerase chain reaction,PCR)结合变性梯度凝胶电泳(denaturing gradient gel electrophoresis,DGGE)基因指纹技术研究不同填埋操作方式,包括高密度聚乙烯膜(high-density polyethylene liner,HDPE)隔离、渗滤液亚表面灌溉和植被种植,对城市生活垃圾填埋场表层覆土中Ⅰ型甲烷氧化菌的群落结构和多样性的影响.16S rDNA序列的系统发育分析结果表明,供试土壤中的Ⅰ型甲烷氧化菌均属于甲基杆菌属(Methylobacter).从香农-威纳多样性指数(Shannon-Wiener diversity index)和主成分分析的结果可以归纳得到:渗滤液亚表面灌溉和植被种植比HDPE膜隔离对表层覆土中Ⅰ型甲烷氧化菌群落结构的影响更大,它们会降低Ⅰ型甲烷氧化菌的多样性,并且推测渗滤液亚表面灌溉会抑制Methylobacter的生长.无HDPE膜隔离的土壤中,即有填埋气体侵入的土壤中,随填埋气体作用于土壤时间的延长,Ⅰ型甲烷氧化菌的群落结构会发生变化;覆土时间分别为3周、1.5a和5a的土壤中,Ⅰ型甲烷氧化菌的香农-威纳多样性指数在覆土1.5a时达到最大值.
Type Ⅰ methanotroph is crucial for methane oxidization and it responses fast to the changes in environment. In this study, 16S rDNA-based denaturing gradient gel electrophoresis （DGGE） gene fingerprint technology was applied to investigate the effect of operational modes, i.e. high-density polyethylene liner （HDPE） isolation or subsurface irrigation of landfill leachate and vegetation, on community structure and diversity of type Ⅰ methanotroph in soils covering municipal solid waste landfill. 16S rDNA based phylogenetic analysis reveals type Ⅰ methanotroph in all tested soils belongs to Methylobacter. According to Shannon-Wiener diversity index and principal component analysis, landfill leachate subsurface irrigation and vegetation have more impact on type I methanotroph community structure and diversity than HDPE liner isolation does, and they reduce type Ⅰ methanotroph diversity. Leachate irrigation is supposed to inhibit the growth of Methylobacter population. Community structure of type Ⅰ methanotroph in landfill cover soil isolated by HDPE, i.e. invaded by landfill gas, shifts during long term gas interference. When cover age is 1.5 years old, Shannon-Wiener diversity index of type Ⅰ methanotroph reaches its maximum.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2008年第10期2987-2992,共6页
Environmental Science
基金
国家自然科学基金重点项目(50538080)
国家高技术研究发展计划(863)项目(2003AA644020)
国家科技支撑计划项目(2006BAC06B05)
