Fauna edáfica e sua relação com os atributos químicos e físicos de um solo construído, após 14,6 anos de revegetação

Abstract

Opencast coal mining generates large-scale impacts on the environment, with soil physical, chemical and biological modifications, making it difficult for the newly soil to return to its pre-mining state of organization in the short term. In this sense, soil fauna can be used to assess the recovery status of a degraded area, as there is a direct relationship between soil organisms and its environmental quality, especially the mobilization of nutrients and the improvement of soil structure. Therefore, the objective of this work was to evaluate the biological, chemical and physical attributes of a minesoil after 14.6 years of revegetation with perennial grasses. The study was carried out in the experimental area of UFPel inside the Candiota coal mine. The minesoil was constructed in 2003 and in September/October 2007 the following perennial grasses were implanted: Hermartria altissima Cynodon dactylon, Panicum maximum, Urochloa humidicola and Urochloa brizantha. In 2022, soil samples were collected in the 0-10 cm layer of the minesoil to determine the fauna abundance and diversity, microbial biomass carbon, basal respiration, soil organic carbon content and its chemical fractions, soil density and porosity. The effect of perennial grasses on the minesoil attributes recovery was compared with a control soil. After 14,6 years of revegetation with perennial grasses, the minesoil physical attributes are well established. On the other hand, the positive relationship between fauna, microbial biomass and soil organic carbon content is still in an initial process, possibly due to the relatively short recovery time of the mined area.