Effect of municipal solid waste leachate on soil enzymes

Abstract

The paper aims to investigate the enzyme activity of soils exposed to Municipal Solid Waste (MSW) leachate. Soil enzymes are useful indicators for soil quality management as they respond to changes that occur in soil quality. To determine the effects of MSW leachate, three sites, i.e. Leachate Exposed Site (LES), Partially Leachate Exposed Site (PES) and Control Soil (CS) were considered located in and around Kapuluppada dumpsite which falls under Visakhapatnam city limits. The LES soil receives more leachate washings due to its proximity to waste heaps compared to PES soil. The third site, i.e. CS is located a little away from the MSW heaps and is free from any contamination. The samples were estimated for enzymes like dehydrogenase, invertase, alkaline phosphatase, protease, amylase and cellulase activity using standard assay methods. The following trend was observed: protease>amylase>invertase>alkaline phosphatase>dehydrogenase>cellulase. Our results indicate that the enzymes showed higher activity with MSW leachate washings due to enhanced soil aeration and soil porosity. However, MSW leachate washings had not shown any significant inhibitive effect on organic carbon content, microbial biomass and enzymatic activities.