祁连山多年冻土区甲烷通量与甲烷微生物群落组成的关系

全球变暖可能导致多年冻土中的有机碳分解，向大气释放甲烷（CH₄），但多年冻土的甲烷释放通量与微生物群落结构以及功能基因的丰度相关性还不清楚.于2019年6月~2020年1月，选择青藏高原北部祁连山多年冻土区，利用静态箱-气相色谱法对不同海拔地区进行CH₄释放通量测定，并分析土壤理化性质、CH₄功能微生物群落、功能微生物的基因丰度.结果发现，整体上，甲烷通量随着海拔的上升而增加，在4 100 m和3 900 m处表现为源，而其他各海拔地区表现为碳汇.土壤含水率、电导率和mcrA基因丰度与CH₄通量正相关.研究表明祁连山多年冻土区不同海拔CH₄通量受土壤含水率和mcrA基因丰度的影响，而有机碳含量会影响微生物的多样性. 

Methane Fluxes and Their Relationships with Methane-Related Microbes in Permafrost Regions of the Qilian Mountains

Global warming may cause the decomposition of organic carbon in permafrost regions and release methane (CH₄) into the atmosphere, while the correlation between methane fluxes in permafrost regions and the structure of methane-related microbes and the abundance of functional genes remains unclear. In this study, we selected the permafrost region of the Qilian Mountains in the northern Qinghai-Tibet Plateau, and the field work was conducted from June 2019 to January 2020. The CH₄ fluxes were measured at different altitudes using static chamber-gas chromatography. The soil physical and chemical variables and abundances of CH₄ function genes were analyzed. The results show that the methane fluxes largely increased with the altitude. It appeared as a source at 4 100 m and 3 900 m, while other altitude areas appear as carbon sinks. The soil moisture content, conductivity and mcrA gene abundance were positively correlated with CH₄ fluxes. The results showed that CH₄ flux at different altitudes in the permafrost regions of Qilian Mountains were affected by soil moisture content and mcrA gene abundance, while organic carbon content mainly affected microbial diversity.