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甲烷是仅次于CO_2的第二大温室气体.森林表层土壤中甲烷好氧氧化作用是大气甲烷重要的汇,在碳循环和减缓全球变暖方面起着重要作用.研究不同植被类型土壤中甲烷氧化菌的群落结构及多样性,有助于更好地理解植被演替、人为干扰和不同土地利用背景下甲烷氧化菌群落组成和多样性变化与地上植被之间的相互关系.本研究在贡嘎山东坡海拔梯度上的4种不同植被类型中采集了92个土壤样品,利用Miseq测序技术和生物信息学方法评估了甲烷氧化菌群落组成及多样性在4种不同植被类型间的变化,并探讨了其变异的潜在原因.结果表明:常绿阔叶林和针阔叶混交林土壤中甲烷氧化菌的群落结构较为相似,暗针叶林和灌丛草甸土壤甲烷氧化菌的群落结构较为相似.4种不同植被生态系统中,针阔叶混交林土壤中的甲烷氧化菌α多样性显著高于其他3种植被生态系统(P<0.001),且暗针叶林和灌丛草甸土壤中甲烷氧化菌β多样性显著高于常绿阔叶林和针阔叶混交林(P<0.001).Spearman相关分析表明,不同类型甲烷氧化菌的相对丰度对环境变化的响应模式不同.造成α多样性差异的主要因子可能是土壤总氮、电导率和土壤温度.偏Mantel检验分析和冗余分析(RDA)表明,常绿阔叶林和针阔叶混交林土壤甲烷氧化菌多样性受环境因子的影响较大,而暗针叶林和灌丛草甸土壤中甲烷氧化细菌多样性变化可能存在其他潜在的影响因素或者机制.降水可能是造成低海拔常绿阔叶林和针阔叶混交林与高海拔暗针叶林和灌丛草甸土壤甲烷氧化细菌群落结构差异的主要原因.贡嘎山海拔梯度上不同植被类型土壤中甲烷氧化菌的群落结构和多样性变化可能主要是由于土壤理化性质和气候变化综合作用的结果.
Methane is the second largest greenhouse gas next to CO 2. The aerobic oxidation of methane in the forest surface soil is an important sink of atmospheric methane and plays an important role in the carbon cycle and mitigation of global warming. The community structure and diversity of the oxidative bacteria help to better understand the relationship between the composition and diversity of methanotrophs and the vegetation on the basis of vegetation succession, anthropogenic disturbance and different land use. Ninety-four soil samples were collected from four different vegetation types on the eastern slope of Mt. Gaoshan, and the changes of composition and diversity of methanotrophs in four different vegetation types were evaluated using Miseq sequencing and bioinformatics methods. The possible causes of variation were discussed.The results showed that the community structure of methanotrophs was similar in the evergreen broad-leaved forest and the coniferous and broad-leaved mixed forest, and the community structure of methanotrophs in the dark coniferous forest and shrub meadow was more (P <0.001), the α diversity of methanotrophs in the soils of coniferous and broad-leaved mixed forests was significantly higher than that of the other three vegetation ecosystems The β diversity of methanotrophs in dark coniferous forest and shrub meadow soil was significantly higher than that in evergreen broadleaved forest and coniferous broadleaved mixed forest (P <0.001) .Spearman correlation analysis showed that the relative abundance of different types of methanotrophs The main factors influencing the diversity of α may be soil total nitrogen, conductivity and soil temperature.The partial Mantel test and the analysis of the redundancy (RDA) showed that the evergreen broad-leaved forest and the needle width The diversity of methanotrophs in mixed soil is affected by environmental factors, but there may be other potential influencing factors or mechanisms in the changes of methanotrophs in the soil of dark coniferous forest and shrub meadow. Precipitation may be the cause of low The Main Reason for the Difference of Metabolism of Methane Oxidation Bacteria among Different Vegetation Types in the Altitude Gradient of Elevation of Gongga Mountain and Dark-coniferous and Mixed Forest in High Altitude Changes in community structure and diversity may be mainly due to the combined effect of soil physical and chemical properties and climate change.