Regeneração natural de espécies arbóreas de interesse comercial em área submetida ao manejo florestal em pequena escala no Médio Amazonas

Abstract

Small-scale forest management is practiced by small landowners, but the lack of information on the forest's ability to regenerate prevents a better understanding of the true impacts caused on the structure and dynamics of the forest. In this study, we evaluated the natural regeneration of commercial tree species in an area subjected to small-scale, low-impact forest management. For this, a study was carried out in an area of terra firme forest that suffered exploitation in 2020, located in the municipality of Silves, Amazonas, in the middle Amazon region. Twenty gaps were selected, which were characterized according to size, canopy opening and edge forest height. Natural regeneration was diagnosed in all gaps from the identification of saplings (height > 1.3 m) of commercial tree species in nine plots of 2 x 2 m. Canopy opening was associated with gap size, but not associated with forest height at the gap edge. A total of 205 individuals were found belong to 42 species and 11 botanical families. The three species that were most repeated in this study were Protium apiculatum, Protium decandrum and Goupia glabra with 47, 30 and 10 individuals respectively. Each gap had an average of 10.25 individuals, and an average of 1.14 individuals per plot. Regarding the species, each gap presented an average of 2.1, and an average of 0.23 species per plot. Canopy opening was positively associated with species abundance and species richness. On the other hand, no association between canopy opening and the composition of species regenerating in gaps was observed. Therefore, the availability of light, represented by the canopy openness, positively affects the number of seedlings and species of natural regeneration in logging gaps in a small-scale, low-impact forest management area. However, the disproportion in the distribution of species among the seedlings – most seedlings were of a few species – suggests the need for enrichment plantations to improve the composition of commercial species in the gaps.