Linking topography, soil variability, and early successional vegetation in abandoned gold mines in the tropical rainforest of Colombia's Chocó Biogeographic region

Abstract

Soil fertility heterogeneity is one of the main factors affecting early recovery and plant succession toward a target plant community. This study examined the influence of topography on the diversity and composition of plant communities established in areas degraded by opencast mining in Chocó, Colombia. Soil fertility and plant community were characterized in the four topographic formations identified in the abandoned mines: plains (PL), slopes (SLP), floodplains (FP), and sand and gravel mounds (SGM). Topographic formations did not result in significant differences in soil properties. However, a gradient of fertility and vegetation cover was observed: from the SGM, with less fertile soils and little vegetation, to the PL, SLP, and FP, with the most fertile soils and greater vegetation cover and density. The species composition found in PL, SLP, and FP was similar but differed from that of SGM. These results suggest that the SGM does not promote early revegetation in the mines. However, experimental studies are necessary to determine how topographic formations and soil conditions resulting from mining should be managed to facilitate the early recovery of vegetation and the ecological restoration of areas affected by mining.