Role of revegetation in restoring fertility of degraded mined soils in Ghana: A review
The topsoil gets seriously damaged during mineral extraction. The consequences of physical disturbance to the topsoil during stripping, stockpiling and reinstatement results in soil degradation through loss of soil structure, accelerated soil erosion, excessive leaching, compaction, reduced soil pH, accumulation of heavy metals in soils, depletion of organic matter, decreased plant available nutrients, reduced cation exchange capacity, decreased microbial activity and consequent reduction in soil fertility. Management of topsoil is important for reclamation plan to reduce nutrient losses and eventually restore the fertility. Revegetation constitutes the most widely accepted and useful way to improve the fertility of degraded mined lands. A review was conducted to assess the contribution of revegetation to improvement of soil fertility of mined lands. The results obtained in this study indicate that revegetation through forest vegetation is one of the efficient means of restoring soil fertility through improvement in soil organic matter content, available nutrients, cation exchange capacity, increased biological activities as well as improvement in physical conditions of the soil. However, it will require longer periods to restore the fertility as closely as possible to the original level. The efforts to rehabilitate mined lands have focused on N-fixing species of legumes, grasses, herbs and trees. Some of the promising tree species that can be used for revegetation are Acacia, Leucaena and other legume trees that are acid-tolerant and can add substantial amount of organic matter to the soil. Long term revegetation using legume species of high metal accumulation and are acid tolerant should therefore be considered in mining areas. .