Efeito da inundação no recrutamento e na dinâmica populacional de Vochysia divergens Pohl (Cambará), Pantanal, MT, Brasil

Abstract

The present study objective to verify the process of recruiting Vochysia divergens Poh lthrough dynamic flooding in wetland. We tested the hypothesis of competition between cohorts, and this negatively affect the density of young individuals. We also tested the hypothesis that growth of this species, which sought to clarify whether the growth of this species was higher during the dry season, because this species is a light demanding. Our sampling was performed in seven permanent plots in the grid Pirizal and supplemented with three plots around the grid. For the sampling of seedlings and young, we used a range of 4 meters, two meters either side of the centerline of the plot (250 m). For the identification of these individuals in the field, use a tape labeler (9mm x 2m), where all individuals were tagged, seedling height was measured with a ruler. For the sampling of adult and juvenile trees use wide range of 20 meters, and 10 meters either side of the centerline of the plot, juveniles with DBH ≥ 3 cm and trees with DBH ≥ 5 cm were sampled. To remove the data in circumference, use a tape measure and the height was estimated. To collect data in circumference, use a tape measure and the height was estimated. For the identification of tree within the plots, we use aluminum plates properly numbered. We used linear regression models for adults and Poisson regression for the young and juveniles, to determine whether the water depth influenced the density of individuals. Among the 10 plots surveyed in this study, 3978 individuals were sampled Vochysia divergens Pohl, with 2694 trees, 1202 young and 82 juveniles. The effect of the flood was dependent on the age group of individuals, where the young and juveniles were more sensitive to the effects of flooding. Regarding the effect of adults on young, we note that under low density of adults, there may be a low level of recruitment as a high level recruitment. We conclude that the flood changes the density of young and juveniles, but in relation to adults this effect is not noticed.The density of adults affects youth development resource by restricting competition and shading. The growth of the species Vochysia divergens Pohl was higher during the dry season, because this species has a high capacity for photosynthesis, favoring their development quickly.