Impact on short term changes in soil microbial biomass, carbon and nitrogen dynamics due to irrigation with distillery effluent in rice-wheat cropping system

Utilization of anaerobically digested distillery effluent (DE) in agriculture represents a means to convert wastes to value added resource as it contains appreciable amount of N, K and other macro and micronutrients required for crop growth and does not posses any toxic elements. We studied the impact of its irrigation in conjunction with irrigation water in Rice-Wheat cropping system on short term changes in soil microbial biomass carbon and nitrogen dynamics, which is an indicator of long-term sustainability of any agricultural land. Application of DE at the rate of 60 m³ ha⁻¹ in four split doses in conjunction with irrigation water increased soil microbial biomass carbon (C_mic) and nitrogen (N_mic), without causing any major shift in bacterial community structure. Although variation in soil organic carbon (C_org) due to DE application was non significant but significant increase in soil C_mic to C_org ratio shows that the high carbon content of DE degraded rapidly in soil and got org incorporated in soil microbial biomass without affecting soil health. Application of DE at the rate of 60 m³ ha⁻¹ seems to be promising as it increased soil microbial biomass and also improved the C_mic:C_org ratio by getting degraded without affecting org soil health.