SOIL ORGANIC MATTER AND NUTRIENT CYCLING TO SUSTAIN AGRICULTURE IN THE SOUTHEASTERN USA
Location: Athens, Georgia
Title: Response of soil microbial communities during changes in land management
Submitted to: The ISME Journal: Multidisciplinary Journal of Microbial Ecology
Publication Type: Abstract Only
Publication Acceptance Date: August 23, 2010
Publication Date: August 23, 2010
Citation: Jangid, K., Williams, M.A., Franzluebbers, A.J., Schmidt, T.M., Coleman, D.C., Whitman, W.B. 2010. Response of soil microbial communities during changes in land management. The ISME Journal: Multidisciplinary Journal of Microbial Ecology. No Page Numbers.
The response of soil microbial communities to restoration following disturbances is poorly understood. We studied the soil microbial communities in a forest disturbance-restoration series comprising a native deciduous forest (DF), conventionally tilled cropland (CT) and mid-succession forest (SF) restored in 1964 at the W. K. Kellogg Biological Station, Michigan. In addition, the effect of vegetation and historical management was also investigated. Within the disturbance-restoration series, the total microbial phospholipid fatty acids (PLFA) and soil microbial biomass C decreased with disturbance from DF'CT and then increased upon restoration from CT'SF. While there was no change in the bacterial diversity, the microbial communities were significantly different. 16S rRNA gene based taxa-specific comparisons revealed significant changes in the composition of four of the eight phyla compared. In addition, four phyla also showed significant changes in the relative abundance. The specific association of some most abundant operational taxonomic units with these soils further illustrated the changes in community structure. With different vegetation, the conifer forest (CF) soils had significantly different community composition and lower pH, C and N content, soil microbial biomass, PLFA and 16S rRNA gene diversity than DF soils. Comparison of mowed grassland (MG), which was derived from forest, and an annually burned early-succession (ES) grassland, which was derived from cropland in 1989, revealed significant differences in the composition of microbial communities, soil C, and microbial biomass. In contrast, the bacterial diversity did not change significantly. This suggests that the management history is more important determinant of the current bacterial community than land use. In conclusion, disturbance, vegetation and historical management play significant roles in shaping the composition of soil microbial communities.