Fitossociologia de uma área de preservação permanente na Fazenda Rio Capim, Paragominas, PA.

Abstract

This work presents the phytosociology of an area of 84ha of primary forest in the Rio Capim farm in the municipality of Paragominas, Pará state, and investigates plants from 30cm in height and above, The data were collected from 12 plots of lha, subdivided into 100 subplots of 10 x lOm. Ten of these subplots were randomly selected, within which the small trees (5.0cm < dbh < 20cm) were identified and measured. Within these 10 selected subplots 10 smaller plots were selected (5m x 5m), where saplings (2.5cm < dbh < 5.0cm) were identified and measured. Within these plots of 5m x 5m, triangles of 6.25m2 were randomly selected, where the seedhngs (with height greater or equal to 30cm and DBH < 2.5cm) were identified and measured. 4926 individuais were found in total, in 185 species and 47 botanical families distnbuted in the following size classes; Trees' contained 2326 individuais, distributed in 163 species, 109 genera and 45 families; 'small trees' contained 1093 individuais, distributed in 115 species, 83 genera and 40 families; 'saplings' contained 383 individuais, distributed in 73 species, 58 genera and 34 families; and 'seedlings' contained 1124 individuais, distributed in 87 species, 69 genera and 37 families. The most important families were Leguminosae and Lecythidaceae on the florist composition and forest structure, The fírst family had more species than the second. However Lecythidaceae had more individuais than Leguminosae. Considering basal area and relative frequency ofthese species it is necessary to priorize these families in silvicultural systems on the areas with the same characteristics of the study area. The species richness in the study area is similar to the most of Amazonian dry forests as shows the diversity index of Shannon-Weaner. Shadow profitable species were more important but species with great commercial values were expressive too. Most of the more important ecological species in the area was presented in the four size class (tree, small tree, sapling and seedling) then, if the forest continue preserved, these species probably will be existing for a long time, Neighbor forests with similar structure to this studied could be exploited on a sustainable yield, with the mmimal alteration on their ecology considering their natural consistency. Some species as Pouteria sp., Eschweilera amazônica, Eschweilera hlanchetiana, Protium apiculaíum, Guatteria poeppigiana, Stercuha pilòsa, Duguetia echinophora, Rinorea flavescens, Eperna bijuga, Inga brevialata and Licania heíeromorpha could be used for restoration in the altered or degraded areas in riparian forests or in the margins of water courses in grassland areas in the Rio Capim farm and neighborhood, based on the ecological importance of these species on the studies conservation area. However, before any change action it must take secure informations about siviculture ofthese species.