Utilizing urban refuse wastes as soil amendment in sub-Saharan Africa: Prospects and challenges in the Nigerian context

Abstract

The challenge of effectively managing the huge wastes generated in most Nigerian cities raises serious environmental concerns with environmental pollution and ecological deterioration being the most serious concerns. Most municipal authorities responsible for evacuation of town refuse wastes lack the capacity to effectively manage the huge volumes of wastes generated on daily basis due to a number of reasons prominent of which include population explosion, urbanization, industrialization and economic growth. Application of urban refuse wastes (URW) to crop fields offers means of correcting many of the problems associated with collection and disposal of URW in Nigeria. Utilizing organic solid wastes on agricultural fields is an important way of effectively increasing soil organic carbon sequestration and supplying nutrients for crop plants. Proper sorting and composting of the URW has been shown to not only improve the quality of the wastes as organic amendment, but also help in correcting many of the health and environment related challenges associated with its direct application to agricultural lands. This review presents the results of research findings on utilization of URW as organic amendment and also highlights the constraints, prospects and the sustainability for utilizing URW as bio-fertilizer. It reveals that the average solid wastes generated in most Nigerian cities have a large fraction of organic materials that could easily be utilized as bio-fertilizer. Suggestions on ways to reduce some of the problems associated with land application of URW are proffered. Possible ways for improving the quality of URW intended for use as organic amendment are also suggested.