Management of ecological filters for increasing the native vegetation cover in a mine treated with sewage sludge in the Cerrado Biome

Abstract

The dominance of invasive species and the compaction of mine surfaces are ecological filters that usually restrict the establishment and growth of native plant species. The understanding of ecological filter mechanisms aiming to overcome their effects on the ecological succession is crucial for the ecological restoration of ecosystems. In order to evaluate the effects of reducing the intensity of the surface compaction and the grass dominance on the plant recruitment, we set up 24 experimental plots at six repetitions in a mine dominated by Urochloa brizantha. Treatments consisted in control (T1), herbicide application on U. brizantha (T2), mechanized plowing to ameliorate surface compaction (T3), and the combination of T2 and T3 (T4). Results showed that the chemical attenuation of U. brizantha dominance and surface decompaction allowed the recruitment of 29 plant species, 66% of which are invasive species, exotic to the Cerrado biome. However, the treatments T2, T3, and T4 resulted in the formation of richer and more diverse plant communities in comparison to the plots used as control (T1). U. brizantha cover redeveloped after both surface unpacking and herbicide application, but the plant species that recruited on U. brizantha cover in the meantime improved the ecological condition in experimental plots.

Keywords:
Glyphosate; Soil compaction; Ecological restoration; Urochloa brizantha