Co-composting Versus Direct Ponding of Sewage Sludge on Soil Nutrients Redistribution

Depriving soil fertility serves as one major cause for reduced crop growth rate and production, which in turn affects the food productivity. Various soil conservation measures to sequester the soil nutrients are adopted in developing countries locally and conventionally. In another scenario, present day sewage treatment plants (STP) across the nation are struggling to treat the receiving water quantity effectively. The fluctuations in receiving quantity of waste water resulted in untreated excess sludge dumping in nearby places. In order to synergize the excess sludge dumping in a feasible way by land management practices, the present study aims to compare two methods of sludge incorporating into soil, namely co-composting and direct ponding. Samples were collected from two different plots receiving sludge for different duration (fresh and old) at different depths (12 cm, 24 cm and 36 cm) and analyzed for various physicochemical parameters. The study also highlights the co-composting of sewage sludge with other community wastes to contribute a better analogy on nutrient redistribution. The obtained results of 17.34 mg/l total organic carbon and 1.392 mg/l total nitrogen at 36cm depth in old sludge ponding sites reveals the improved capability of sludge leachate against the soil nutrient attenuation. It finds application in agricultural practice to promote crop growth under controlled conditions of sewage sludge amendment as ponding and co-composting.