Microbial Biomass Carbon Status in Agro-Ecological Sub Regionsof Black Soils in India

Abstract

The present study was undertaken with an objective to study the impact of pedo-edaphic environments, cropping systems, land use, and management practices on the MBC. Soil samples were collected from seventeen benchmark soils representing different agro-ecological subregions of black soil region of India. The pooled comparisons of MBC in different bio-climates indicated significant differences (p \ 0.001) between the bio-climates. Significantly higher (p \ 0.001)MBCwas recorded in sub-humid dry bioclimate (267 lg g-1) followed by sub-humid moist and least in arid bio-climate (97.5 lg g-1). In cropping systems, legume-based system (205 lg g-1) had higher MBC. The lowest MBC was recorded in cotton-based system (128 lg g-1). In soil sub-groups, Halic Haplusterts showed higher MBC (209 lg g-1) followed by Typic Haplusterts (208 lg g-1), while the lowest MBC was observed in Gypsic Haplusterts (98.5 lg g-1). Significantly higher (p \ 0.05) MBC was recorded in high management and irrigated agro-systems as compared with low management and rainfed agro-systems. The MBC content in the soil is significantly and positively correlated with organic carbon %, total culturable microbial population, nitrogen content, and available water content.