Use of compost for the restoration of mine wastes and mine soils (Utilización de materiales compostados en la rehabilitación potencial de espacios afectados por residuos mineros y suelos de mina)
Résumé
One of the main limitations for the successful restoration of the environmental damages produced by quarrying and mining activities is that mine waste and mine soils are largely devoid of organic matter. For this reason, amelioration with organic materials such as sewage sludge, manure or compost is gaining attention as a desirable strategy that may render good results in restoration. In this paper, recent experiences on the use of composted materials for the amelioration of mine wastes and mine soils are reviewed. The benefits obtained from the use of compost in restoration studies include improvement of the unfavourable physical, chemical and biological properties of mine waste and mine soils. The increase in the organic matter concentrations produces an improvement of the structure which leads to reduced bulk density and increased porosity, thus decreasing the risks of compaction, sealing and erosion. Correction of extreme pH is usually observed. N and P, two elements that are usually lacking in mine waste, are also added with compost in plant-available forms. The introduction of microbial populations leads to the reactivation of biogeochemical cycles which are essential for the long-term fertility and sustainability of new ecosystems.