Alternative silvicultural stand densitymanagement options for Chilimo dry afro-montane mixed natural uneven-aged forest using species proportion in Central Highlands, Ethiopia

Abstract

Chilimo forest is one of the few remnants of dry afro-montane mixed uneven aged natural forest located in Central Highlands of Ethiopia. Also it has been during the last century one of the most exploited and disturbed forest in the country. Stand density management diagram (SDMD) is a stand-level model that graphically illustrates the relationships between wood yield, density and mortality throughout all stages of stand development. SDMD is a useful tool for designing, displaying and evaluating alternative density management regimes for both even-aged and uneven-aged forest stands. However, information in this regard and other silvicultural management operations are lacking for most Ethiopian forests in general and Chilimo dry afro-montane forest in particular. The purpose of the study is to develop a SDMD model for the existing mixed natural forest using appropriate species proportion for Juniperus procera and Podocarpus falcatus. Two linear equations were simultaneously fitted to relate quadratic mean diameter with stand density and dominant height and relate it to total stand volume with quadratic mean diameter, stand density and dominant height. Moreover, dominant height and quadratic mean diameter were found to be the best endogenous variables for SDMD for Chilimo forest. The relationship between stand density, dominant height, quadratic mean diameter and stand volume are represented in the SDMD graph. Formulating SDMD using species proportion is better than treating each species independently. This SDMD is the first diagram model developed for mixed-forest in Africa and it canbe servingfor sustainable management of Chilimo dry afro-montane forest in particular and other dry afro-montane forests in general.