Guias de densidade e índices de sítios para Hovenia dulcis Thunberg na região central do estado do Rio Grande do Sul, Brasil

Abstract

The main objective of this dissertation is to build site index curves relating dominant height and age and to elaborate density management diagram (DMD) for individuals of Hovenia dulcis located in the central area of the state of Rio Grande do Sul, Brazil. To do that, it was used information from 4 stands, aged 25, located at Fundação de Pesquisa Agropecuária (FEPAGRO) and from a population of free trees, with DAPs varying from 5 to 45 cm, located at the campus of Universidade Federal de Santa Maria (UFSM), both in the municipal district of Santa Maria. For the construction of the sites indexes, information from 18 dominant trees was gathered in the 4 stands located at FEPAGRO, observing the methodology for trunk analysis. In places where trees were under competition, data for the elaboration of the density management diagrams were collected in trees of dominant, intermediate and dominated strata, considering the method of the punctual density. In the place where trees were free from competition, census was made. As a result, in the elaboration of the site index curves, the Backman model was selected, being verified the necessity of construction of two groups of index curves, from 5 to 25 years-old, with interval of 2 meters and index of 25. For the Site I-A, 3 index curves were created from 22 to 24 meters and, for the join of the Sites I-B+II+III, 6 index curves from 8 to 18 meters were produced. It was also possible to conclude that the Reineke model adjusted itself to calculate the closing density lines of the dossal and of the self-thinning, with angular coefficients very close to -1.5, for both of them, being demonstrated that the potency law of -3/2 of self-thinning was taken into account and that it was very similar to the hypothesis postulated by Reineke. The population density, for the beginning of the total capacity of the dossal, was of 42.5% of the maximum number of trees that the place allows, and that, with the collected data, it was possible to build diagrams for the density management, from the 5 to the 31 cm of diameter of the tree of medium basal area.