Agrobiodiversidade, produção de serrapilheira e cobertura do solo em sistemas agroflorestais de região semiárida

Abstract

Conventional agriculture has been questioned due to the negative environmental impacts, which result in loss of biodiversity and reduction of soil quality. Agroforestry systems (AFS's) are one alternative for sustainable agricultural production. The present study evaluated four AFS's conducted in different management systems and in different successional stages, having a regenerating forest as a control treatment. The systems were implemented with the support of CETRA – Center for Labor Studies and Assistance to Workers, in an agro-ecosystem in the community of Serrotinho, in the municipality of Tururu-CE. The evaluation of agrobiodiversity was made from the floristic survey in the entire area and calculation of the Shannon index. The litter sampling was carried out using a frame of 0.25x0.25 m with 10 replicates per area. The ground cover was evaluated with 5 replicates by a 3.4 m long rope with 10 cm equidistant marks, resulting in 33 marks. The presence or absence of cover in the projection of each mark was observed. The AFS showed a greater diversity of species according to the Shannon index compared to the forest regeneration area. Litter production was higher in areas with the introduction of fast-growing species with great biomass production potential. Soil cover was similar in all areas, except for SAF IV, which had little vegetation cover, due to recent implantation and the absence of biomass producing species in a short period of time. Agrobiodiversity was important for greater biomass production and, consequently, greater land cover in the SAF areas.