Capacidade produtiva em floresta de planalto no Baixo Tapajós, Amazônia Oriental.

Abstract

The classification and mapping of sites, together with all the data present in the management plan are important tools for planning forest management. Having this information it is possible to infer their quality with regard to production capacity and stock related a given product. This study aimed to identify classes of productive capacity of the forest and to valuate commercial forest products occurring in the Zone for management of Non Timber Forest products of the Tapajós National Forest covering an area of 36.925,33 hectares. A total of 94 plots of 30 x 250 m, were randomly placed, which summed up a total sampled area of 70,5 ha. The size classes (CT): CT, - 10 em < DAP <25 cm in subplot 30 m x 50 m; CT, - 25 em < DAP < 50 em subplot of 30 m x 100 m; and CT3 - DAP > 50 cm in the plot of 30 m x 250 m were inventoried in each plot. The Cluster analysis was performed using the software MATLAB. For the valuation of the forest products, with a market value, the 50 most important species as the importance value were considered, by selecting trees with DAP > 50 em (timber) and DAP > 25 cm (non-timber), applying if the criteria of maintenance and felling, in accordance with the standards of environmental agencies, and using two scenarios that the maximum intensity of logging (IMC) of 30 m? ha” and the real potential of forest harvesting. The valuation of forest timber products was based on wood price adjusted by the Forest Service in 2013 for the concession contract and the value of non timber forest products (NTFPs) was obtained in fairs of Santarém-PA and Coomflona (Cooperative mixed of the Tapajos National forest), considering the price paid in the forest. Through cluster analysis identified two forest sites valued, respecting the IMC presented an estimated R $ 216.209,26 for the site IT and R $ 179.468,00 for site II per work unit (UT = 100 ha), and when it was not considered the IMC, the site I also presented higher value, where the difference was R$ 73.482,53. The valuation of forest (timber and non-timber) was estimated at R $ 218.939,26 by UT for the site T and R $ 186.377,00 for site II, considering the value of wood products when estimated based on the IMC, and R $ 290.151,42 and US $ 220.826,19 for UT to sites 1 and II, respectively, regardless of IMC. The forest management zone Non Timber presented low stock of NTFPs and high stock of commercial timber, especially Manilkara huberi, Hymenaea courbaril and Handroanthus impetiginosus. The two sites showed a potential for timber production higher than 30 m? h".