An evaluation of potential Oak decline Forest of the Zagros using GIS, RS, FAHP methods

Destruction of oak forests in Zagros and its impacts on the economy of Iran have motivated experts of natural resources to study its affecting factors. Researchers have found the most important of destruction is climate changes. Because of the importance of the subject, a proper method for data analyzing, decision making and recognition of potentials of the oak forest decline is needed. In this study, to map the respective susceptible zones, RS/GIS and hierarchical-fuzzy analysis techniques were applied. For this purpose, the slope, aspect, elevation classes, temperature, rainfall, dust and soil were considered as governing factors. Hence, physiographic and climatic maps were initially prepared. Due to the different impact of each factor, they were valued based on the expert judgements and and FAHP. The fuzzy maps were developed using the linear ascending and descending fuzzy and Gaussian distribution functions. Also, through the overlaying of various layers, the areas exposed to drying were mapped and classified. This research suggests that the map prepared by the fuzzy gamma distribution with a precision of 70% has the highest correlation with field data . Furthermore, southern and western areas are most susceptible to severe forest drying.