MICROBIAL SOIL RESPIRATION AND IT'S DEPENDENCY ON SOIL MICROBIAL COMMUNITIES, ORGANIC CARBON & MOISTURE IN DIFFERENT DRY TROPICAL ECOSYSTEMS

Abstract

The relationship between environmental changes and microbial respiration is critical for projecting changes in soil carbon fluxes. The variation in OC, microbial-C and moisture among different soil profiles of Jharkhand, India were analyzed. The OC, microbial-C and moisture varied from (0.174-2.469)%, (55.586–646.703) mg/g soil and (6.643–11.329)% respectively. The OC was positively correlated with microbial-C (r=0.985; p<0.01) and moisture (r=0.979; p<0.01). The MB-C:OC ratio ranged from (2.6-3.9) %, and BSR:OC from (1.271-0.382)%. The basal soil respiration and microbial metabolic quotients ranged from (0.348-0.945) mg CO₂-C/g soil/hr and (6.2605-1.4612)x10^-3 mg CO₂-C/g microbial-C/hr respectively. Microbial populations across the sites were estimated. Stepwise multiple regression analysis determines the degree of influence contributed by microbial community, OC, microbial-C and moisture on microbial soil respiration. Principal component analysis was able to discriminate different soil profiles, which correlated well with land degradation, and thus can serve as a biomarker of soil fertility.