Relação hipsométrica em um fragmento de floresta Peri urbana na fazenda experimental de Igarapé Açu, Pará

Abstract

The hypsometric relationship (RH) is of fundamental use in forest inventories because it reduces data collection time and costs. Although it is widely studied in forest plantations, the hypsometric relationship still lacks studies in native forests of the Amazon, mainly on how to build it. Therefore, the present work aimed to test and select models to adjust the hypsometric relationship in a secondary forest in the Amazon. Data were obtained from a fragment of native peri-urban forest located in the municipality of Igarapé Açu, northeast of Pará, with an area of ​​44 hectares, included in the Forest Management Project of the Laboratory of Forest Measurement of UFRA-Belém. Ten models were tested, including Simple Linear, Assmann, Trorey, Incomplete Parabola, Polynomial, Exponential-Curtis, Henricksen, Potencia-Stofells, and Hyperbolic models. Statistical parameters such as the adjusted coefficient of determination (R²aj.), the standard error of the estimate (Syx%). The best statistics were for the Exponential-Curtis, Power Stofell and the hyperbolic equation, they obtained the best adjustments, a fact observed by the standard error value of the estimate, which was in the range of 18.37% to 18.79%, being very high compared to the values ​​that can be found in the literature.