Effect of MSW Compost on Microbiological and Biochemical Soil Quality Indicators

This laboratory incubation study was conducted to evaluate the effect of municipal solid waste compost (MSWC) as a soil amendment on soil quality indicators, such as microbial biomass, and their activities. The MSWC was compared against cow dung manure (CDM), a traditional organic supplement. The comparative study was carried out in water regimes of 60% water holding capacity (WH) of soil and under waterlogged (WL) condition. MSWC was applied to an alluvial soil (Typic Fluvaquent) at the rates of 0, 2.5, 10, 20 and 40 and CDM at 0, 20 and 40 t/ha. Microbial biomass-C (MBC), glucose induced soil respiration (SR), urease and acid phosphatase activities in soil were analyzed following 15, 30, 45, 60, 90 and 120 days of incubation. The parameters studied were significantly higher in CDM-treated than in MSWC-treated soils. Increase in graded doses of MSWC from 2.5 to 40 t/ha substantially increased the MBC, SR, urease and phosphatase activities in the soil. In 60% WH regime, MBC and SR increased for the first 30 days of incubation and then declined. Under the WL regime, the MBC declined while SR increased from 15 days till 120 days of incubation. Urease and phosphatase activities of soil increased for up to 60 days during incubation in 60% WH regime and then decreased. Activities of both the enzymes under WL regime decreased progressively during incubation. There were no negative impacts on the soil quality indicators from high application rates of MSWC.