title: Bacterial, archaeal and fungal succession in the forefield of a receding glacier.
abstract: 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.
authors.affiliation: Forest Soils and Biogeochemistry, Swiss Federal Research Institute WSL, Zürcherstrasse 111, 8903, Birmensdorf, Switzerland.
authors.forename: Anita
authors.initials: A
authors.lastname: Zumsteg
authors.forename: Jörg
authors.initials: J
authors.lastname: Luster
authors.forename: Hans
authors.initials: H
authors.lastname: Göransson
authors.forename: Rienk H
authors.initials: RH
authors.lastname: Smittenberg
authors.forename: Ivano
authors.initials: I
authors.lastname: Brunner
authors.forename: Stefano M
authors.initials: SM
authors.lastname: Bernasconi
authors.forename: Josef
authors.initials: J
authors.lastname: Zeyer
authors.forename: Beat
authors.initials: B
authors.lastname: Frey
mesh_terms: D001105:Archaea / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D017753:Ecosystem; D005658:Fungi / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D046448:Ice Cover / Q000737:chemistry / Q000382:microbiology*; D008969:Molecular Sequence Data; D010802:Phylogeny; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology; D013557:Switzerland
chemical_list: D012987:Soil