Abstract

SANTIAGO-GARCIA, Wenceslao et al. Prediction of Pinus patula Schl. et Cham. timber yield through diameter distribution models. Agrociencia [online]. 2014, vol.48, n.1, pp.87-101. ISSN 2521-9766.

The region of Zacualtipán, Hidalgo, Mexico, is characterized by the presence of even-aged stands of Pinus patula Schl. et Cham., a fast-growing timber species with high economic and ecological value. Having forestry tools to predict its growth and yield is a fundamental requisite to plan its sustainable management. The objective of this study was to present two prediction systems for timber yield of P. patula stands with the diameter distribution models approach. In their construction, dasometric data from 126 diameter distributions were used, which were obtained from 42 permanent sampling plots of 400 m², located in the Ejido La Mojonera, municipality of Zacualtipán, Hidalgo. Stand diameter distribution was estimated through Weibull's probability density function (pdf) (1951) with percentile prediction and the free distribution method based on percentiles. The means comparison with Tukey test (p≤0.05), for total volume predictions obtained with the two diameter distribution systems, shows that there are no significant statistical differences between the total volume predicted by both systems. However, the system based on Weibull's probability density function is easier to use because its parameters are dependent on the stand's minimum diameter and quadratic mean diameter, and it requires the prediction of only two percentiles. The diameter distribution models presented allow estimating the diameter structure of a stand as it changes with stand age. Therefore, their use is recommended as a support tool for management plans of P. patula stands.

Keywords : diameter distribution; Weibull distribution; percentiles; implicit prediction.