A forest management planning tool to create highly diverse uneven-aged stands

Abstract

A new model for computing the allowable cut for uneven-aged stands is described. The model is focused on the Gini index against basal area and the target structure of stand volume on diameter classes, assumed to be achieved by the end of transformation period from even-aged to the uneven-aged structure. The real structure of the stand is characterized by a given Gini index while the target structure is characterized by a benchmark Gini index. In order to determine the benchmark Gini index, the model allows the establishment of target structure of the stand based on a new idea: target structure of trees number in diameter classes for a particular stand corresponds to a certain target distribution of volumes on diameter classes. According to the difference between the two mentioned Gini indices, a certain period for directing the real structure to the target structure is further chosen while the computation of the allowable cut is based on the assumption of Gaussian distribution of volume against diameter classes. Eventually, the computation of allowable cut takes into account the stand growth, the differences between the real and the target growing stock, the adopted transformation period and the management goals. © Institute of Chartered Foresters, 2011. All rights reserved.