Espécies exóticas invasoras em unidades de conservação da Cidade do Rio de Janeiro, RJ - Estudo da população de jaqueiras (Artocarpus heterophyllus L.) no Parque Natural Municipal do Mendanha, RJ

Abstract

Amongst the allien species invading the units of conservation of the city of Rio de Janeiro, the jackfruit (Artocarpus heterophyllus L.) detaches for presenting a great frequency. It is observed in diverse forest fragments, with individuals in the different phases of growth. Its control passed to be considered of great importance. However, so that this control can give through measures effective, it must be known the characteristics of the current population, its horizontal and vertical structure. This study Rio de Janeiro, was carried through in the Municipal Natural Park of the Mendanha, in the period of September of 2006 the January of 2007. The area of studies was divided in area of more intense and less intensive use, and the general objective of this study was to carry through a survey of areas invaded for Artocarpus heterophyllus L. to base methods of handling and population control of invading species in units of conservation. The methodology used for accomplishment of the present study was to the allocation in the Field of four parcels, two in the area and less intensive use and two in the area of more intense use, these parcels were divided in ten sub-parcels of 10 size x 10 meters, having totalized 4000m ² in the two areas. The individuals had been evaluated according to its frequency, density, dominância, value of importance and value of covering, had been used the indices of diversity of Shannon, equabilidade of Pielou and index of similarity of Sorënsen for comparison with other studies carried through in the Atlantic Forest. They had been found a total of 280 individuals divided in 43 species and 22 families in the two areas. The showed parcels had presented a great similarity between itself, not only for the great number of individuals of the Artocarpus heterophylus L. species, but also for the numerous other common species. The index of diversity of Shannon was considered low if compared with other studies in Atlantic forest. The species that had presented greater index of value of importance and covering had been Artocarpus heterophyllus L.and Guarea guidonia, both the species had presented these values due to the high value of basal area of each one of them. In the two areas the Artocarpus heterophyllus L. presented high values of density, frequency and dominance