تحقیقات جنگل و صنوبر ایران (Sep 2010)
Evaluation of felling productivity in Shafarood forest (Guilan province)
Abstract
Felling as the initiation of harvesting chain-work is the first step for preparing trees to market consumption which has severe effect on the subsequent work stages. The aim of this research is to assess the productivity of manual felling and costs of felling team as well as recognizing their effective factors. In this evaluation after identifying work elements of one felling turn, 72 felling turns were time studied. Furthermore independent variables such as tree diameter at cutting stump height, distance between trees, longitudinal and latitudinal slopes were time studied in each turn. Felling time regression model is a function of independent variables such as tree diameter and distance between trees. Amount of production including delay time and without delay time were 63.48 and 83.19 m3 per hour, respectively. The cost determination model which recommended by Forests, Rangelands and Watershed Organization project work agenda was used to determine felling costs. Therefore, felling costs with delay time and without delay time were 4017 Rials per m3 (26872 Rials per tree) and 3065 Rials per m3 (20516 Rial per tree), respectively. The under cut and back cut time and technical delays formed the greatest felling element time of chain saw felling. Examination of the variation effect of the variables on time due to the variation of felling cost showed that increasing in each of the variables causes an increase in time and therefore increases felling costs.