Forest Soils and Biogeochemistry, Swiss Federal Research Institute WSL, Zürcherstrasse 111, 8903, Birmensdorf, Switzerland.
Microb Ecol. 2012 Apr;63(3):552-64. doi: 10.1007/s00248-011-9991-8. Epub 2011 Dec 13.
Glacier forefield chronosequences, initially composed of barren substrate after glacier retreat, are ideal locations to study primary microbial colonization and succession in a natural environment. We characterized the structure and composition of bacterial, archaeal and fungal communities in exposed rock substrates along the Damma glacier forefield in central Switzerland. Soil samples were taken along the forefield from sites ranging from fine granite sand devoid of vegetation near the glacier terminus to well-developed soils covered with vegetation. The microbial communities were studied with genetic profiling (T-RFLP) and sequencing of clone libraries. According to the T-RFLP profiles, bacteria showed a high Shannon diversity index (H) (ranging from 2.3 to 3.4) with no trend along the forefield. The major bacterial lineages were Proteobacteria, Actinobacteria, Acidobacteria, Firmicutes and Cyanobacteria. An interesting finding was that Euryarchaeota were predominantly colonizing young soils and Crenarchaeota mainly mature soils. Fungi shifted from an Ascomycota-dominated community in young soils to a more Basidiomycota-dominated community in old soils. Redundancy analysis indicated that base saturation, pH, soil C and N contents and plant coverage, all related to soil age, correlated with the microbial succession along the forefield.
冰川前缘年代序列最初由冰川后退后的贫瘠基质组成，是研究自然环境中微生物初始定殖和演替的理想场所。我们对瑞士中部 Damma 冰川前缘暴露岩石基质中的细菌、古菌和真菌群落的结构和组成进行了描述。在没有植被的细花岗岩砂等靠近冰川末端的地方到植被覆盖良好的成熟土壤等前缘各个站点采集了土壤样本。利用基因指纹图谱（T-RFLP）和克隆文库测序研究了微生物群落。根据 T-RFLP 图谱，细菌的 Shannon 多样性指数（H）较高（范围为 2.3 至 3.4），没有沿前缘的趋势。主要的细菌类群为变形菌门、放线菌门、酸杆菌门、厚壁菌门和蓝细菌门。一个有趣的发现是，广古菌门主要定植于年轻土壤，而泉古菌门主要定植于成熟土壤。真菌从年轻土壤中以子囊菌门为主的群落转变为成熟土壤中以担子菌门为主的群落。冗余分析表明，与土壤年龄相关的碱饱和度、pH 值、土壤 C 和 N 含量以及植物覆盖率与前缘的微生物演替相关。
