Study on Site Preparation and Restoration Techniques for Forest Restoration in Mining Tailings of Mariana, Brazil

Abstract

Ecological restoration in forest ecosystem is a priority in Mariana, Brazil. Thus, we evaluated the effects of passive and active restoration methods through different site preparation techniques by manipulating physical-chemical properties of substrates on tree community coverage in Mariana, Brazil. A total of 48 plots (12 × 12 m each) were established in two areas along the flood plains with accumulation of tailings. The following treatments were established: (1) planting of native tree seedlings with fertilization (PSf) and (2) without fertilization (PS); (3) direct seeding of native trees with fertilization (SDf) and (4) without fertilization (SD); (5) natural regeneration with fertilization (NRf) and (6) without fertilization (NR). Differences in substrate properties and tree community coverage were evaluated between treatments, the substrate properties and tree community coverage relationship, and main effects of substrate fertility and texture on tree community coverage. There were marked differences in substrate and plant coverage between treatments. On average, the highest plant coverage was found in treatment with fertilization, such as NRf (59,5%) and SDf (48%). However, the treatment with seedling planting (PSf and PS) and NR did not show differences (~37%), while the lowest values were observed in SD (23%). There is a strong relationship between substrate fertility and plant community coverage, with significant positive effects. We observed that the passive and active restoration methods can be complementary in the soil and plant community coverage recovery.