Efeito de condicionantes ambientais no incremento diamétrico de Peltogyne gracilipes Ducke (Leguminosae) em área de ecótono no norte de Roraima

Detalhes bibliográficos
Ano de defesa: 2019
Autor(a) principal: Santos, Raylanne de Lima
Orientador(a): Não Informado pela instituição
Banca de defesa: Não Informado pela instituição
Tipo de documento: Dissertação
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Universidade Federal de Roraima
Brasil
PRPPG - Pró-reitoria de Pesquisa e Pós-Graduação
PRONAT - Programa de Pós-Graduação em Recursos Naturais
UFRR
Programa de Pós-Graduação: Não Informado pela instituição
Departamento: Não Informado pela instituição
País: Não Informado pela instituição
Palavras-chave em Português:
Link de acesso: http://repositorio.ufrr.br:8080/jspui/handle/prefix/427
Resumo: The vulnerability of the Amazon rainforest to dry events is becoming increasingly evident, especially in areas with climatic seasonality. Interest in this theme has been increasing due to concerns related to changes in tropical forests, especially regarding climate variations and their effects on carbon accumulation. In order to verify the behavior of tree individuals and to understand the mechanisms that influence carbon accumulation in trees, this study aimed to determine the intra-annual variations in the diameter increment of Peltogyne gracilipes (Leguminosae) along a topographic gradient located in an area of ecotonal forests of northern Roraima. P. gracilipes is a bioindicator species of local vegetation, featuring monodominance in some environments. The abundance of the species is strongly influenced by environmental characteristics and is associated with edaphic factors (soils with high aluminum content) and lower altitude areas (seasonally flooded). We used dendrometers bands to evaluate intra-annual variations in diameter increment and to verify the effect of environmental conditions (canopy illumination index, soil, altitude, abundance and precipitation) in permanent plots of PPBio located at Maracá Ecological Station (Amajarí, RR). Individuals were monitored bimonthly over one year (March/2018 - March/2019). Of the 158 individuals observed, 88% had a mean cumulative diameter growth of 3.4 mm year-1. Intra-annual variation in diameter was observed, with decreased in increment from the beginning of the dry season, reaching an average reduction of 0.71 mm in ~ 81% of individuals in the last measurement (end of dry season). Precipitation explained 68% of the variations in the diameter increment of the species in the model tested It was concluded that rainfall determined intra-annual diameter variations of P. gracilipes in ecotone area in northern Roraima, regardless of altitude, light and soil conditions.