Tree Volume Prediction Model of Cupressus lusitanica Species: in North-Western Highlands of Ethiopia

A significant basis of raw materials for the forest products industry is provided by Cupressus lusitanica, one of the commercial timber tree species found in the forest. Accurate tree and stand volume development models are necessary for intensive forest management to yield timber. The goal of this study was to develop and validate volume equations for Cupressus lusitanica tree species in North-western highlands, Ethiopia. Four tree volume estimation models were developed and validated for Cupressus lusitanica plantation forest at Tsarikan. Tsarikan plantation forest was selected purposively, and systematic sampling technique was employed to select four square plots having an area of 100 m² each. A total number of 46 trees were observed and diameter at breast height and tree height were measured. Among the computed estimation models, an equation that used both tree Diameter at Breast Height (DBH) and height as independent predictors (V = -5.6*10-17+1.25*10-5(DBH2*h)) was selected to be the best fit and suitable model for individual tree volume prediction of Cupressus lusitanica monoculture forest depending on the respective standard error of estimation and coefficient of determination values. This volume estimation model can be used by forest growers and managers for sustainable production and utilization of Cupressus lusitanica plantation forest at North-Western highlands of Ethiopia, as well as other areas of the country having similar agro ecology. The use of species and site-specific models are strongly recommended for the countries having a varied range of topographical and biophysical situations like Ethiopia.