FITOSSOCIOLOGIA E POTENCIAL MADEIREIRO NO SUDESTE DA FLORESTA NACIONAL DO TAPAJÓS, ESTADO DO PARÁ

The objective of this study was to evaluate the phytosociology and timber potential in the southeast of Flona Tapajós, state of Pará. The cluster sampling process was adopted with 36 primary units systematically distributed. These units were composed of four secondary units measuring 20 x 250 m. All trees with DBH > 10 cm were measured, but different size classes and subsamplings were considered. The phytosociological parameters were calculated and the monetary valuation of the forest was carried out following the normative instructions of environmental agencies. The cubic meter of the log placed in the yard was valued considering the price of R$ 380.0 m3. However, 60% was deducted from this amount referring to operating costs, producing a net price of R$ 152.00 m3. The most important species was Pouteria cladantha, but Apuleia leiocarpa, Virola melinonii, Protium paraense, Alexa grandiflora and Manilkara huberi also stood out, mainly due to their tree stock, excellent use in the timber industry and good commercialization. The area presented 126 m3 ha-1 and 13.61 m2 ha-1, of which 54.8 and 41.8%, respectively, were above the minimum harvest diameter. The estimated net profit was R$ 4,047.27 ha-1, demonstrating that the area is suitable for timber forest management.O objetivo desse estudo foi avaliar a fitossociologia e o potencial madeireiro no sudeste da Flona Tapajós, estado do Pará. Adotou-se o processo de amostragem em conglomerado com 36 unidades primárias distribuídas sistematicamente. Essas unidades foram compostas por quatro unidades secundárias de 20 x 250 m. Todas as árvores com DAP ≥ 10 cm foram medidas, considerando diferentes classes de tamanho e subamostragens. Foram calculados os parâmetros fitossociológicos e realizada a valoração monetária da floresta, acatando as instruções normativas dos órgãos ambientais. O metro cúbico da tora posta no pátio foi valorado tendo em vista o preço de R$ 380,0 m3, sendo descontados desse valor 60% referente aos custos de operação, produzindo um preço líquido de R$ 152,00 m3. A espécie mais importante foi Pouteria cladantha, mas Apuleia leiocarpa, Virola melinonii, Protium paraense, Alexa grandiflora e Manilkara huberi também se destacaram, principalmente pelo estoque de árvores, ótimo aproveitamento na indústria madeireira e boa comercialização. A área apresentou 126 m3 ha-1 e 13,61 m2 ha-1, dos quais 54,8 e 41,8%, respectivamente, situaram-se acima do diâmetro mínimo de colheita. O lucro líquido estimado foi de R$ 4.047,27 ha-1, demonstrando que a área apresenta aptidão para o manejo florestal madeireiro. Palavras-chave: Amazônia; valoração de florestas; manejo florestal madeireiro. Phytosociology and timber potential in the Southeast of the Tapajós National Forest, Pará state ABSTRACT: The objective of this study was to evaluate the phytosociology and timber potential in the southeast of Flona Tapajós, state of Pará. The cluster sampling process was adopted with 36 primary units systematically distributed. These units were composed of four secondary units measuring 20 x 250 m. All trees with DBH ≥ 10 cm were measured, considering different size classes and subsamplings. The phytosociological parameters were calculated and the monetary valuation of the forest was carried out, following the normative instructions of Organs environmental agencies. The cubic meter of the log placed in the yard was valued considering the price of R$ 380.0 m3, with 60% being deducted from this value referring to operating costs, producing a net price of R$ 152.00 m3. The most important species was Pouteria cladantha, but Apuleia leiocarpa, Virola melinonii, Protium paraense, Alexa grandiflora and Manilkara huberi also stood out, mainly due to their tree stock, excellent use in the timber industry and good commercialization. The area presented 126 m3 ha-1 and 13.61 m2 ha-1, of which 54.8 and 41.8%, respectively, were above the minimum harvest diameter. The estimated net profit was R$ 4,047.27 ha-1, demonstrating that the area is suitable for timber forest management. Keywords: Amazon; forest valuation; timber forest management