Evaluating the hazardous potential of the dieback of the Zagros Oak forests using the multi-criteria decision-making methods

Oak dieback and mortality, as a multifactorial phenomenon, have occurred in many forests of the world including Zagros forests in Iran. This phenomenon happens due to the complex interaction of the environmental stresses, pests, and socioeconomic issues. Given the importance of this issue, it is necessary to use an appropriate approach to find the areas with potential for dieback in order to guide the analyses regarding the decisions on forest conservation. Therefore, in the present study, geographic information system (GIS) was used to interfere with the analytic network process (ANP), multi-criteria decision making (MCDM), and fuzzy methods for zoning the susceptible areas of Oak forests in Kohgiluyeh and Boyer-Ahmad province in southwest of Iran. Criteria were selected as effective factors for dieback including slope, aspect, elevation, mean annual temperature and precipitation, pest, and distance from the farmlands. After preparing the initial maps of criteria, the weight of each criterion was calculated according to the experts and ANP and the fuzzy criteria maps were prepared using the membership functions, and the final maps of the areas with potential of dieback were produced by overlapping the criteria layers. The results showed that 45.32% of the Oak forests in the province have high and very high potential for dieback in the central and western parts. As a result, these areas have a higher priority for preventive and protective operation. Among the criteria, pests, temperature, and distance from the farmlands had the highest scores. Overall, the results obtained from the MCDM methods were satisfactory and efficient regarding studying the Oak dieback.