آشکارسازی پیامدهای خشک شدن زایند هرود و تغییرات پوشش گیاهی بر دمای سطح زمین درکلا نشهر اصفها ن

Water stress is a major environmental issue and has a significant impact on the sustainability of urban areas worldwide. This study examines the changes in land surface temperature (LST) and their relationship with variations in vegetation cover during wet and dry periods in Zayandeh Rood. To accomplish this, Landsat TM, ETM, and OLI satellite images from three dry years (2001, 2009, and 2018) and three wet years (2005, 2006, and 2020) were used. The research findings indicate that, in 2006, when water was flowing in the river bed, vegetation cover decreased from 36% (201 km2) to 23% (km2) in 2018, when the river bed had no water. Over the last two decades, the Earth's surface temperature has increased. The highest average temperature was observed in 2018, at 40/4 degrees Celsius, and the maximum temperature in the dry years of 2001, 2009, and 2018 was higher than in the wet years of 2005, 2006, and 2020. The highest density of heat islands was observed in regions 2, 4, 5, 6, 7, 14, and east of region 15, which is concentrated on barren lands and then on urban areas. In the dry year of 2009, the total area of temperature classes 42-49 increased by approximately 12% compared to the dry year of 2001 and also increased by about 25% in 2018. In contrast, it was zero in the wet years of 2005 and 2006, and in 2020, it decreased by around 34% compared to 2018. Furthermore, urban development, which has grown by 7/3% over the past two decades, has contributed to the reduction of vegetation and intensified the urban heat island effect. Examining the average temperature changes at different distances from the Zayande Rood indicated that the temperature increased by about 1 degree Celsius with the distance from the river. [ABSTRACT FROM AUTHOR]