Evaluation of Harvest Priority for Sugi Plantations using GIS

Abstract

The most important work in planning harvest schedules is to allocate spatially feasible and economically operable forest stands into harvest blocks. Stands that are more feasible and operable should have a higher priority for harvest than ones that are less feasible and operable. The main objective of this study is to analyze stand conditions and geographic factors to estimate the feasibility and operability of stands in harvest operations with a score evaluation method, and then to apply the grid-cell-based GIS method for classifying harvest priorities of stands. Estimating the feasibility and operability of stands is difficult because it involves complex natural factors such as resource structures, geography, geology, and transportation networks. Among these factors, we selected four simple factors, i.e. stand age, site class, skidding distance and slope angle, which directly affect harvest operations, to analyze harvest priorities for sugi plantations. By using the score evaluation method with four factors, we assigned each stand a value representing its feasibility, locality, and operability, and calculated the total score for the stand. By classifying the total scores into four harvest groups, we evaluated the harvest priority for each stand in the study area. A GIS grid-cell-based model was applied as an efficient means of accomplishing this work.