Estimating balanced structure areas in multi-species forests on the Sierra Madre Occidental, Mexico

Abstract

This study presents a method for estimating the minimum area which exhibits a balanced diameter distribution, and the corresponding number of trees, for different tree species and forest types in the Santiago Papasquiaro region in the State of Durango, Mexico. The balanced structure area is defined as the minimum contiguous area that is required for sustainable management of a multi-sized selection forest. A multi-sized forest represents a balanced structure unit if the relationship between harvest and growth can be maintained, using a defined target diameter distribution and disregarding major natural disturbances. The study is based on 17,577 sample plots in uneven-aged forests, which are selectively harvested by local communities. The minimum structure areas that provide a balanced diameter distribution in the diameter at breast height (DBH) interval of 12 to 57 cm vary from 0.4 to 122 ha, depending on the particular tree species. This study has shown that it is possible to identify silvicultural treatments that are conducive to sustainable use. Future management monitoring in the unique forests of Durango will reveal unsustainable harvesting practices more effectively and in a more comprehensive way than before, using the methods presented in this study.