Community level physiological profile response to plant residue additions in Antarctic soils

Changes in microbial community-level physiological profiles (CLPP) were investigated during decomposition of plant materials in maritime Antarctic soils from Alexander Island and Signy Island. For each soil, a series of microcosms were established and half of them amended with Deschampsia antarctica residues and the other half left unamended (controls). Microcosms were destructively sampled at regular intervals and a soil suspension from each microcosm was used to inoculate BIOLOG EcoPlates. The results showed differences between samples due to the treatment (amendment) but no systematic changes due to incubation period. Microbial response in terms of the overall BIOLOG activity in FB soils was greater than in JC and increased in the former during plant decomposition whilst the overall activity of the JC soils remained relatively unchanged. The differences in the microbial community response to plant amendment between FB and JC may be related to the C:N ratio of these soils and to differences in the way in which the different microbial communities respond to sporadic resource inputs.