ABSTRACT

Studies were conducted at Enugu, South East Nigeria, on the effects of four levels of biosolids (0.0, 10, 20, and 30 ton ha 1) on three degraded soil samples collected from Amaiyi — Obilaohia, Oruruala in lsuikwuato LGA and Ugwu Rubber Erosion sites near lgbere in Bende LGA of Abia State,-Nigeria. The ameliorating effects of biosolids on the degraded soils were carried out in a 4 x 3 factorial experiment laid out in a randomized complete block design (RCBD) and replicated three times. The objective was to use processed biosolid as a cheap source of organic matter and soil conditioner to improve some physical properties and restore productivity of degraded soils. Soil samples were taken from the three sites and analysed, for physical and chemical properties. Sewage sludge samples were collected from the Enugu State Environmental Protection Agency Sewage Dumpsite at Ugwuaji Nike, Enugu State, analysed for nutrichemistry, pathogen densities and composted, using an improvised aerated static pile system. Treatment effects of biosolid on bulk density, total porosity, total N, total organic matter and biomass production were statistically analysed. Results showed that composting effects of biosolid reduced pathogen density, odour and conserved the essential nutrients. Biosolids treatment effect significantly reduced the bulk densities and increased total porosity, total N, total organic matter and biomass production (P<0.05) of the three degraded soils. However, there were no significant differences between 20 ton ha 1 and 30 ton ha 1. Total porosity did not significantly correlate with bulk density for the main effects of biosolid application rates (r= -0.56). Yields of both fresh and dry biomass in the plots treated with 30-ton ha 1 were about three times those obtained from the controi. Further studies on the feasibility of employing the microbial population in biosolids for biodegradation of polyethylene films are recommended. >