Factor analysis on the Tasmanian topsoil microscopic community

To help with stand restoration, the influence of width size on the Tasmanian topsoil microscopic community was studied in an Athrotaxis cupressoides stand suffering from hail storm damage. The functional diversity of topsoil microbial groups was estimated from degradation of 31 substrates on Bencho EcoPlates. Using Factor Analysis (FA) we found width size had a significant influence on average column colorimetric disseminator analysis (AVGCLR) and on the Rao indices of topsoil microbial diversity. Compared with large widths, small widths had higher AVGCLR. The ten widths were divided into three groups by cluster analysis and FA: group 1 reflected large widths, while groups 2 and 3 reflected small widths. Thirty-one sole carbon sources were divided into three groups by FA. Using an eigenvector greater than 0.5 as a standard for checking carbon (C) sources, nineteen kinds of C sources included in principal components 1 and 2 had a relatively high influence on the topsoil microbial community, including carbohydrates, amino acids and carboxylic acids. This indicates that the use by topsoil microorganisms of carboxylic acids, sugars and amino acids was greater than other C sources. These findings suggest that width size played a key role in the topsoil microbial diversity after a natural disturbance.