The soil carbon/nitrogen ratio and moisture affect microbial community structures in alkaline permafrost-affected soils with different vegetation types on the Tibetan plateau.
In the Tibetan permafrost region, vegetation types and soil properties have been affected by permafrost degradation, but little is known about the corresponding patterns of their soil microbial communities. Thus, we analyzed the effects of vegetation types and their covariant soil properties on bacterial and fungal community structure and membership and bacterial community-level physiological patterns. Pyrosequencing and Biolog EcoPlates were used to analyze 19 permafrost-affected soil samples from four principal vegetation types: swamp meadow (SM), meadow (M), steppe (S) and desert steppe (DS). Proteobacteria, Acidobacteria, Bacteroidetes and Actinobacteria dominated bacterial communities and the main fungal phyla were Ascomycota, Basidiomycota and Mucoromycotina. The ratios of Proteobacteria/Acidobacteria decreased in the order: SM>M>S>DS, whereas the Ascomycota/Basidiomycota ratios increased. The distributions of carbon and nitrogen cycling bacterial genera detected were related to soil properties. The bacterial communities in SM/M soils degraded amines/amino acids very rapidly, while polymers were degraded rapidly by S/DS communities. UniFrac analysis of bacterial communities detected differences among vegetation types. The fungal UniFrac community patterns of SM differed from the others. Redundancy analysis showed that the carbon/nitrogen ratio had the main effect on bacteria community structures and their diversity in alkaline soil, whereas soil moisture was mainly responsible for structuring fungal communities. Thus, microbial communities and their functioning are probably affected by soil environmental change in response to permafrost degradation.
MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu 730000, China; Cryosphere Research Station on the Qinghai-Tibet Plateau, State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineer Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China.
Xinfang
X
Zhang
MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu 730000, China. Electronic address: Zhangxinfang@lzu.edu.cn.
Shijian
S
Xu
MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu 730000, China.
Changming
C
Li
Cryosphere Research Station on the Qinghai-Tibet Plateau, State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineer Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China.
Lin
L
Zhao
MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu 730000, China.
Huyuan
H
Feng
Cryosphere Research Station on the Qinghai-Tibet Plateau, State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineer Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China.
Guangyang
G
Yue
MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu 730000, China.
Zhengwei
Z
Ren
Cryosphere Research Station on the Qinghai-Tibet Plateau, State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineer Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China.
Guogdong
G
Cheng
D001419:Bacteria / Q000145:classification / Q000302:isolation & purification*; D058448:Biota; D002244:Carbon / Q000032:analysis*; D005658:Fungi / Q000145:classification / Q000302:isolation & purification*; D009584:Nitrogen / Q000032:analysis*; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology; D018609:Tibet
D012987:Soil; D002244:Carbon; D009584:Nitrogen
Alkaline permafrost-affected soil; Microbial community; Soil variables; Tibetan plateau