Detection of Climate Change Based on Warm Temperature Indices in Zagros Forest Ecosystem; Chaharmahal and Bakhtiari Province

Although one of the most important factors affecting the decline and drying of Zagros forests is the occurrence of climate change, especially during the last two decades, the degradation and decline of Zagros forests can intensify the trend of climate change in this ecosystem. In order to detect the occurrence of climate change in the Zagros oak (Quecus brantii) forests of Chaharmahal and Bakhtiari province, daily data of minimum temperature, maximum temperature and precipitation parameters were used. Data were analyzed for quality and homogeneity and prepared to enter into the climate model that reveals the occurrence of climate change. Warm temperature indicators for climate change detection were calculated, using ClimPACT software in R 2.10 programming environment for the  period of 1992-1999. Trend change, trend slope error and significance of changes were extracted at p = 0.05. The results showed that at all monitoring sites, hot temperature indices, including 2TX2TN SU35, SU30, SU25, TN90p, TX90p, TX50p, WSDI6, WSDI2, had a significantly increasing trend. Changes in the slope of the trend of these indicators coincided with the beginning of the decline phenomenon and have been more intense in the last two decades. Due to the increasing trend of temperature, this increasing trend of indicators will continue in the coming years and the forests of the region will face more drought stress. Awareness of the severity of the changes that have occurred and their continuation in the future can help managers and planners of the Zagros forest ecosystem in operational solutions in adapting to climate change to preserve and rehabilitate forests.