Investigation Of Relevance Between Landslide And Stand Areas On Open Source Web Map (Openlayers): Case Study In Trabzon Region

Abstract

In recent years, the developments in computer technology are as effective in forestry as in many sectors. Open source web map based Geographic Information Systems (GIS) offer a significant advantage in investigating forest structure. When using in open source web maps, the relationships between the data of different features can be evaluated effectively and accurately. In this study, the relationship between online landslide data and online stand data was investigated by coding a web interface with OpenLayers which is one of the common open source web maps. OpenLayers based landslide areas and ArcGIS Web Services based stand areas have been evaluated in the solution process. The parameters of the landslide stands have been evaluated in a case study conducted in Trabzon Regional Directorate of Forestry. Landslide data were obtained from the General Directorate of Mineral Research and Exploration, while stands data were obtained from General Directorate of Forestry. The results indicated that most of the active landslide areas consisted of pure stands (26.71%), mixed stands (20.50%), and agricultural areas (38.51%). It was found that 14.29% of active landslide areas consisted of degraded forest and open areas while 38.51% consisted of agricultural lands. The results also indicated that stands with sparse crown closure covered 32.30% of the active landslide areas, while moderate and dense crown closures covered 12.42 % and 2.48 %, respectively. It was revealed that percentages of landslide areas were high in stands with low crown closure due to effects of heavy rain on the soil. It was also found that mostly tree species with narrow canopy and shallow root formation are subject to landslide incidents. This study suggested that OSWMs can be effectively used to investigate landslide activities in forest areas. It is anticipated that sharing open source data through online databases will provide great opportunity for practitioners and researchers in the field of forestry.