An evaluation of different diameter diversity indices based on criteria related to forest management planning

More attention has been given to tree size diversity in boreal forests over the past few years, mainly because of increased focus on uneven-aged forest management, biodiversity and social values. Objective measures of tree size diversity are needed in order to develop management plans that are sustainable with respect to ecological and economical values. The objective of the present study was to evaluate different indices describing diameter diversity based on criteria related to applications in forest management planning. Eight previously described indices were evaluated based on 16 simulated and 174 empirical diameter distributions. The Gini coefficient was found superior with respect to discriminant ability, capability of providing logical ranking of different distributions and sensitivity to variation in sample size. There is a wide range of possible applications of the Gini coefficient in forest management planning, e.g. to compare tree size diversity in different stands, to assess changes in tree size diversity over time, to quantify the influence of different silvicultural treatments on tree size diversity and to assess areas suitable for certain silvicultural treatments. The coefficient can also be used as an integrated part of growth simulators in order to control the silvicultural treatments in projections. (c) 2005 Elsevier B.V. All rights reserved.