Status: this discussion paper is a preprint. It has been under review for the journal Biogeosciences (BG). The manuscript was not accepted for further review after discussion.
Influence of microorganisms on initial soil formation along a
glacier forefield on King George Island, maritime Antarctica
Patryk Krauze,Dirk Wagner,Diogo Noses Spinola,and Peter Kühn
Abstract. Compared to the 1970s, the edge of the Ecology Glacier on King George Island, maritime Antarctica, is positioned more than 500 m inwards, exposing a large area of new terrain to soil-forming processes and periglacial climate for more than 40 years. To gain information on the state of soil formation and its interplay with microbial activity, three hyperskeletic Cryosols (vegetation cover of 0–80 %) in the recently (< 50 years) deglaciated foreland of the Ecology Glacier and a Cambic Cryosol (vegetation cover of 100 %) behind a lateral moraine deglaciated more than 100 years ago were investigated by combining soil chemical and microbiological methods. All soils are formed in the same substrate and have a similar topographic position. In the upper part of all soils, a decrease in soil pH was observed, but only the Cambic Cryosol showed a clear direction of pedogenic and weathering processes. Differences in the development of these initial soils could be related to different microbial community composition and vegetation coverage, despite the short distance among them. We observed – decreasing with depth – the highest bacterial abundances and microbial diversity at vegetated sites. All soils were dominated by bacterial phyla such as Proteobacteria, Actinobacteria, Bacteroidetes, Acidobacteria, Verrucomicrobia, and Chloroflexi. Multiple clusters of abundant OTUs were found depending on the site-specific characteristics as well as a distinct shift in the microbial community structure towards more similar communities at soil depths > 10 cm. In the foreland of the Ecology Glacier, the main soil-forming processes on a decadal timescale are acidification and accumulation of soil organic carbon and nitrogen, accompanied by changes in microbial abundances, microbial community compositions, and plant coverage, whereas quantifiable silicate weathering and the formation of pedogenic oxides occur on a centennial to a millennial timescale after deglaciation.
Received: 03 Jun 2020 – Discussion started: 31 Jul 2020
Publisher's note: Copernicus Publications remains neutral with regard to jurisdictional claims made in the text, published maps, institutional affiliations, or any other geographical representation in this preprint. The responsibility to include appropriate place names lies with the authors.
Department of Geosciences, Research Area Geography, Laboratory of Soil Science and Geoecology, Eberhard Karls University Tübingen, 72070 Tübingen, Germany
present address: Department of Chemistry and Biochemistry, University of Alaska Fairbanks, 99775-6160 Fairbanks, USA
Department of Geosciences, Research Area Geography, Laboratory of Soil Science and Geoecology, Eberhard Karls University Tübingen, 72070 Tübingen, Germany
Soils from the recently deglaciated foreland of the Ecology Glacier, King George Island, were analyzed using soil chemical and microbiological methods to gain insight into the state of soil formation and its interplay with microbial activity. In the foreland of the Ecology Glacier, acidification, soil carbon/nitrogen accumulation, and changes in microbial communities and vegetation were observable on a decadal timescale, whereas weathering processes occur centuries/millenia after deglaciation.
Soils from the recently deglaciated foreland of the Ecology Glacier, King George Island, were...
- Printer-friendly version
- Supplement
