Análise comparativa de planos de manejo florestal em pequena escala no município de Boa Vista do Ramos, Amazonas

Abstract

In order to obey th legal requirements in the state of Amazonas, a category of forest management was instituted called Small Scale Forest Management, this category aims to assist small producers of the state interior with lands up to 500 hectares. Through the Instituto de Desenvolvimento Agropecuário e Florestal Sustentável do Estado do Amazonas (IDAM), technical assistance was provided to small producers wishing to carry out small-scale management on their properties. The survey of the species of commercial interest for these producers is important to evaluate the potential of each area. In this context, the objective of this work was to analyze the phytosociological differences of Small Scale Forest Management in the municipality of Boa Vista do Ramos - AM. A total of 30 Forestry Management Plans were analyzed in 03 (three) different areas, with 10 (ten) management plans per area, with a total number of 300 ha, and 10 ha in each management plan. These areas are: Curuçá, Monte Horebe and São Tomé.Phytosociological parameters were used to analyse the horizontal structure of the vegetation, as well as the Shannon diversity index (H '), the Simpson dominance index (C) and the Pielou equability index (J'). The forest inventory showed 1,130 individuals represented by 76 species in the Curuçá area, 1,108 individuals distributed in 75 species in the São Tomé area and 1,082 individuals represented by 85 species in the Monte Horebe area. The dendrometric parameters studied in the three areas have a total number of trees (NT) of 3,320 individuals; abundance (AB) of 33.20 trees / ha; total volume of 12,665.23 m³; volume per hectare of 126.65 m³; total basal area of 1,165.82 m²; and, basal area per hectare of 11.69 m². The Importance Species Index (IND) of the three areas showed that all species have good potential for forest management. The analysis of distribution by diameter class for the three areas of study showed unanimity in the behavior of this distribution, with distribution in "Reverse J" for all areas. When comparing the results phytosociological descriptors for the three areas, it can be seen that the species, Manilkara huberi (Ducke) Chevalier of Sapotaceae Family, Hymenaea courbaril Linn. of family Leg. Caesalpinioideae, Goupia glabra Aubl. of family Celastraceae, Lecthis pisonis Cambess. of family Lecythidaceae, Nectandra discolor (H.B.K) Ness of family Lauraceae, are present with a total 1,076 individuals distributed in the three areas, the other 2,244 individuals, are distributed in the other families. The diversity of species, estimated by the Shannon diversity index among the three areas, did not change, presenting an average value of H '3.84, which represents a relative high value of floristic diversity. The Pielou equability index (J) of the three areas showed no difference, averaging 0.86, which means that there is no dominance of one or a small group of species in the areas, indicating high floristic heterogeneity.