A Study On Measuring An Objective Aspect Score In Forestry Analysis: Example Of Forest Roads And Landslide Areas

Abstract

In forestry, measurements are made to understand the state of natural ecosystems, their changes, and human impacts. These measurements are accepted as criteria in studies and used in evaluations and comparisons. Although the studies using these criteria vary, they are of great importance in studies on forest roads and landslide areas. While forest road construction activities affect ecological, economic and social factors in forestry, landslides negatively affect the environment and people. In this study, it is aimed to objectively and accurately measure the aspects of landslides and forest roads. The aspect value has been associated with exposure to sunlight, precipitation and winds that absorb soil moisture in the literature, and it has been concluded that it is an important criterion. The measurement and scoring of the aspect is generally done by visual and subjective methods in the literature. Therefore, a method which measures the aspect score more sensitive and universal is required. In the study, thirty forest roads and thirty landslide areas were selected from the Maçka Forestry Enterprise. These road and landslide areas were scored according to previous studies in the literature. The comparisons have shown that studies on aspect scoring are subjective methods that contradict each other in many ways. In order to eliminate this confusion, in this study, a pixel-based method that can be used for both accurate measurement of the aspect and objective aspect scoring is proposed. Since the hemisphere, the local winds and the precipitation are effective in scoring the aspect, the proposed method is suggested as a parametric model so that users can adapt it to their own work as they wish. The results showed that the proposed method is accurate and effective in measuring and scoring the aspect. In addition, the proposed method is shared as an open source ArcMap Toolbox to be delivered to the end-user.