Stand structure analysis in pure and mixed beech and silver fir woods in Mediterranean environment

Abstract

Stand structure analysis of forest systems, in addition to ecological and dendroauxometric factors, has to consider also dimensional, spatial and chronological aspects of the single subjects. In Mediterranean environment, in the past, forest resources management was founded on strong intensity interventions, followed by pretty long periods of abandonment, or on empirical treatment types linked to local uses and traditions. Different forest stand conditions allow to analyze the consequences of these interventions on the stands structure. In this study, structural characteristics of some systems, among the most significant of the Calabrian Apennine, are studied, with particular reference to pure and mixed beech and silver fir woods, previously subjected to differenttreatment modalities. Four structure typologies have been examined: a) monoplane beechwood; b) pluristratified beechwood; c) pluri-stratified mixed beech-silver fir high forest; d) pluri-stratifiedsilver fir wood. Several indexes, based on the neighborhood relationships, have been utilized to characterize their structure heterogeneity. The analysis pointed out that the application of treatment types referable to the shelterwood method produced simplified stands. The incomplete application of this treatment in all its phases, after the nonexecution of the last removal cutting, instead, determines processes that lead to complexstructures. Furthermore management based on selection cutting allowed, on one side themaintenance of the mixed beech - silver fir woods, and on the other side the conservation of high structural complexity.