Insights into the Application of Co-composting for Soil Nutrient Stability-A Review

Abstract

The recycling of waste organic materials for energy and nutrient recovery has gained immense attention over all spheres of life especially during the past few years. There is an increasing trend of opting co-composting as a feasible technology for easy conversion of organic wastes into nutrient-rich manure. However, their success on direct field application still suffers from nutrient instability, volatility, pathogenic infection, etc., leading to the unprecedented nutrient loss and environmental contamination. Despite these limitations, co-composting offers a sustainable soil amending system whereby the bio-chemical ecology of the soil and crops can be synergistically preserved with enhanced productivity. In this review, a critical comparison is presented to comprehend the need for changing agricultural practices in view of modified soil nutrient dynamics by analyzing (i) the soil characteristics before sowing and after harvesting, (ii) the role of emerging wastes in composting processes, (iii) the methods of field application, and (iv) the agronomic characteristics of sugarcane crop in a composted soil. The study shows that the co-composting of sludge and agricultural waste resulted in maximum cane yield per hectare (150 to 315 tonnes). The sludge-based co-composting is found to retain soil nutrients for a prolonged duration thus promising nutrient sequestration and minimizing subsurface contamination.