Relationship between soil seed bank and forest restoration techniques on areas around bauxite mining environment

Abstract

The soil seed bank is one of the most important ecological indicators to evaluate and monitor the ecological restoration process of plant communities. We aimed to evaluate the influence of ecological restoration techniques on the plant community diversity and composition and functional group composition of the soil seed bank in two bauxite mining areas under compensatory restoration, Southeast Brazil. 30 soil samples were collected in each area (Area_A – Forest restoration by planting seedlings and nucleation techniques and Area_B – just restoration by planting seedlings). The samples were transported to a shade house and evaluated for six months, where germinated individuals were counted and identified weekly. The results indicated that the soil seed banks of the two areas are floristically similar (with a predominance of pioneer, herbaceous and native origin species), which show a higher natural regeneration potential. However, the higher species richness and abundance of zoochoric individuals in Area_A demonstrate that nucleation techniques, such as topsoil transposition and direct seeding were efficient to increase the recovery potential re-establishment. In the early successional stages, restoration techniques are more determinant in the functional group composition than in the floristic composition of the soil seed bank.