Estrutura populacional de Colophospermum mopane em resposta a sua exploração pelas comunidades no Parque Nacional de Banhine

Abstract

The population structure of a plant community is typically influenced by exploitation man-made forest. Despite being a factor causing changes in standards structures of vegetation, little is known about the influence of the distance between the forest and human settlements in the population structure of a plant community. In this study the objective was to analyze the population structure of C. mopane in relation to the exploration distance by communities within and buffer zone of Banhine National Park. To this end, they were two selected communities: Tchai-Tchai (buffer zone) and Tchove (inside the park) where A total of 36 squares measuring 20 x 20m were outlined following an imaginary transect made at basis of a disturbance gradient taking into account the fixed distance of 500 meters from the human settlements inside the forest. In each area corresponding to a distance, a survey of regenerating individuals (seedlings and juveniles) and adults was carried out, where measuring diameters using a suta and visual estimation of heights. With individuals sampled, structure distribution models were constructed, growth in diameter and height and the regeneration capacity of the species. The results demonstrated that the distribution of the diameter structure of the C. mopane population in the Tchai-Tchai community it follows the distribution pattern that fits the inverted J model, however, in the community of Tchove it was found that no area presents a model that fits to the inverted-J model. For growth analysis, the Tchai-Tchai community demonstrated that diametric structure and height of C. mopane individuals was greater in very dense forest areas distant from the community and smaller individuals were noticeable in areas located away from the area closest to human settlements, statistical analyzes (ANOVA) demonstrated that there are significant differences in the diameters and height of C. mopane individuals between areas with different exploration distances of resources with (F=8.92; p<0.001) and (F=11.22; p<0.001) respectively. In the community of Tchove, nearby and distant areas have individuals with smaller diameters and heights, statistical analyzes (ANOVA) demonstrate that there is no significant differences in the diameters and height of individuals between areas of different exploration distances (F=0.68; P> 0.05). In the regeneration of individuals, in the community of Tchai-Tchai, there was a higher density of juveniles and seedlings in areas close to human settlements and in Tchove the density of juveniles and seedlings does not vary exponentially depending on the distance between human settlements and the forest, thus the distance between human settlements and the forest is a determining factor for the structure population of C. Mopane.