Florística e estrutura espacial: 15 hectares de parcelas permanentes na Floresta Densa de Terra Firme na Amazônia Central

• Ano de defesa: 2010
• Autor(a) principal: Silva, Kátia Emídio da
• Orientador(a): Martins, Sebastião Venâncio
• Banca de defesa: Azevedo, Celso Paulo de , Gleriani, José Marinaldo
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Ciência Florestal
• Departamento: Manejo Florestal; Meio Ambiente e Conservação da Natureza; Silvicultura; Tecnologia e Utilização de
• País: BR
• Palavras-chave em Português: Amazônia Central; Distribuição espacial; Análise de gradientes
• Palavras-chave em Inglês: Central Amazonia; Spatial distribution; Gradient analysis
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::RECURSOS FLORESTAIS E ENGENHARIA FLORESTAL::CONSERVACAO DA NATUREZA
• Link de acesso: http://locus.ufv.br/handle/123456789/544

In order to understand the mechanisms responsible for maintaining the high biological diversity in the tropics, resulting from the interactions between the species and the natural environment and among each other, it is essential to minimize the shortage of information in the forestry sector, and to contribute to the restoration, conservation, and sustainable multiple use of the forests. This thesis aimed to describe and analyze the floristic composition and structure of 15 hectares of a dense terra firme forest, located in the experimental site of Embrapa Western Amazonia, Manaus, Amazonas, Brazil. Two main topics were developed: i. Floristic composition and similarity compared to nine other areas inventoried in the state of Amazonas; ii. Horizontal structure, including explicit spatial analyses of the tree community, using the Ripley K function, and neighbor analyses of four tree species of commercial interest in the state of Amazonas. A total of 8771 individuals were identified, representing 264 species and 53 families. The families with the highest species richness were: Fabaceae-Faboideae (22 species), Fabaceae-Mimosoideae (22), Sapotaceae (22), and Lecythidaceae (15). The family Burseraceae, with the lowest species diversity (7), had the highest number of individuals. The ten most abundant species, which comprised 40% of the number of individuals identified, were Protium hebetatum (1037 individuals), Eschweilera coriacea (471), Licania oblongifolia (310), Pouteria minima (293), Ocotea cernua (258), Scleronema micranthum (197), Eschweilera collina (176), Licania apelata (172), Naucleopsis caloneura (170), and Psidium araca (152). There was a high incidence of rare species in the area, with approximately 36% having only 1 individual per hectare; as well as of species with low abundance and occurrence that were limited to some parcels, especially those occurring in the smallest Importance Value Index- IVI classes. The structure of trunk diameters is similar to that found in other studies, with the distribution of diameters having an inverted-J-shaped profile, and 80% of the individuals concentrated in the 10-30 cm DBH classes. The floristic similarity was high (> 60%) among the parcels of the study area, and in general, considering all the plots analyzed, the greater the geographical distance, the lower was the floristic similarity among them. The variables of soil (fertility, moisture, and texture) and topography exerted a strong influence on the spatial arrangement of the tree community, and a spatial dependence was observed between the species and the environmental variables. However, the spatial patterns were only perceived in parcels with a minimum size of 10,000 m2, and were most evident at parcel sizes above 14,000 m2, suggesting that environmental heterogeneity and minimum size of the study area should be taken into account in studies of the dynamics of the terra firme forest in Amazonia. The results of the analysis of the neighbor relationships of the four tree species of commercial interest in the state of Amazonas, Brosimum spp., Eschweilera coriacea, Ocotea cernua, and Protium hebetatum, demonstrated a high occurrence of conspecific neighbors of the focal species, principally at short distances, showing that the focal species are more subject to intraspecific interactions, showing a taxonomic pattern associated with the focal species. The spatial structure, more than the abundance of the focal species Brosimum spp. and Ocotea cernua, contributed to the encounters of conspecifics of the two species, evidencing the importance of spatial structure for ecological interactions. Rare species occurred associated with the focal species, principally with Protium hebetatum, once more emphasizing the importance of defining management strategies to prevent local extinctions of rare species. This thesis contributed to knowledge of the floristic composition and spatial structure of the tree species of the terra firme dense forest in Amazonia, thus supporting actions for the management, conservation, and restoration of tropical forests.