Seleção e avaliação de espécies arbóreas para enriquecimento de florestas secundárias, no município de Bragança, Pa.

Abstract

Secondary forests, known regionally as capoeiras, are now of great socioeconomic and environmental importance, as the number of areas abandoned by migratory agriculture and extensive cattle ranching increases. This type of vegetation has been growing at a fast pace, replacing primary forests in tropical regions. Secondary forests, in addition to environmental services, can offer various products for human use, such as fruits, medicinal plants, melliferous, ornamental, building materials and wood of high commercial value. Scientific studies that subsidize management actions and a better use of the products and services that can offer the "capoeira" are still scarce in our region. The project aims to develop scientific research, validation and technology transfer to small producers in the northeast of Pará. The part of the present study is directed to select tree species from secondary forests with potential use, for germination test, and later to be used in management, in the municipality of Bragança, PA. The selection of the species, Simarouba amara Aubl., Tapirira guianensis Aubl., Agonandra brasiliensis Miers ex Benth., Diplotropis guianensis Benth. and Dipteryx adorata Aubl. was made through information from farmers in the area and the project database. The seeds were collected from selected matrices in a secondary forest area and transported to the seedling nursery of the Museu Paraense Emílio Goeldi, where the experiment was carried out. Sowing was done in treatments using as substrates: black soil, vermiculite, coconut fiber and sand for the species Diplotropis guianensis, black soil and vermiculite for the species Agonandra brasiliensis; coconut fiber and vermiculite for the species Tapirira guianensis; coconut fiber, vermiculite and black soil for the species Simarouba amara and, finally, sand, vermiculite and black soil for the species Dipteryx odorata. From the data collected, it was found that the germination process was slow and with marked unevenness among the selected species.