Predicting the Land Degradation Changes in the Dust Center Under the Influence of Climate Change Phenomenon (Case study: Southeast Dust Center of Ahvaz)

The Climate Change is a complex atmospheric-oceanic phenomenon on a global scale. This phenomenon leads to improper distribution of climatic factors, reducing the quality of water and soil resources, and ultimately erosion and land degradation. The aim of this study was to predict the effects of climate change on land degradation and the development of dust in the dust center of southeastern Khuzestan. Therefore, one of the three-dimensional paired oceanic-atmospheric models of AOGCM called HadCM3, to simulate climatic variables of temperature, wind, precipitation and evaporation and transpiration; Used under diffusion scenarios B2 and A2. In order to downscalling daily climatic data, the SDSM model was used and also to simulate the land degradation process, the Modified MEDALUS model was used. The results of studying different climate change scenarios showed that the amount of precipitation in the next period compared to the base period under scenario A2 will increase by 6.4% and under scenario B2 will increase by 4.8%. Both scenarios jointly predicted an upward trend in regional temperature for both periods. But the slope of this increase under scenario A2 was greater than B2. The results showed that due to changes in precipitation and temperature, the amount of evapotranspiration in the next period compared to the base period under scenario A2 will increase by 14.3 % and under scenario B2 will increase by 9.1%. The highest correlation between the modeled and observed values was obtained in precipitation and temperature parameters (between 86% to 98% in all models). Finally, the research showed that in the land units of the southeastern dust center of Ahvaz, the average land degradation in the future period compared to the base period under scenario B2 will increase by 1.6-2.63% and under scenario A2 will also increase by 2.34-2.94. Therefore, the rate of land degradation in this region is partly affected by changing climate change scenarios. Therefore, despite the confirmation of the existence of climate change in the southeastern part of Ahvaz, it seems that other factors such as managerial and human factors such as land use change, intensification of human activities in the study area have played a more prominent role than climate change.