Slope gradient but not slope position affecting microbial community
composition in the cropland of typical black soil region
Abstract
Soil microorganisms are the main driving force in soil ecological and
biogeochemical processes, such as carbon mineralization, humus
formation, and nutrient cycles. Soil erosion may dramatically alter
microbial properties. However, it is still unclear how soil microbial
characteristics affected by soil erosion. In hilly areas, soil erosion
is highly attributed to topographic characteristics such as slope
position and slope gradient. Herein, we compared the soil microbial
characteristics between different slope gradients and positions in the
farmland in the typical black soil area of Northeast China. The relative
abundances of major microbial phyla are illustrated. Proteobacteria,
Acidobacteria, Gemmatimonadetes, Planctomycetes, and Actinobacteria
accounted for 83% of the total bacterial sequences, and Ascomycota,
Basidiomycota, and chytridiomycosis accounted for 78% of total fungal
sequences in the studied area. Microbial alpha-diversity (Bacteria and
Fungi) was similar among the slope gradients or slope positions. The
bacterial and fungal community composition was only affected by slope
gradient, which was significantly lower in the highest slope gradient
level than in others. This study suggests that slope gradient but not
slope gradient affecting microbial community composition in the cropland
of black soil region.