Modeling Rainfall Changes and Their Effects on Soil Moisture Stress and Vegetation Cover in Sulaymaniyah Governorate Using GIS and Remote Sensing

Abstract

Recent studies have proven that climate elements, especially rain, are beginning to record general trends toward decrease in many countries as one of the important and clear indicators of climate change, which has become a reality that cannot be ignored, as many global, regional, and local studies have proven that, and this is what appeared clearly in the study area through analysis. The general trend of four stations within the study area, as it showed that there is a clear trend towards a decrease in the amount of rain there, which resulted in a change in its quantity during the selected study period from (1991-2020), as the amount of change ranged from (-36.2) mm at Dokan station to ( 8.1-mm at Halabja station

 It was also demonstrated through the use of remote sensing techniques and geographic information systems to analyze Landsat (5, 7, 8) satellite data, represented by visuals captured in selected years representing rain change models and captured in the spring season coinciding with the peak of vegetative growth of plant covers in the study area, and to extract the results of the treatments. Its numbers, represented by the moisture stress index (NDMI) and the vegetation index (NDVI), showed that there was a correlation between the levels of soil moisture stress in the selected years and the amount of rain. It was an inverse relationship with high and medium moisture stress (-0.222, -0.787), respectively, while it was a direct relationship with The two categories of moderately humid and very humid lands (0.595, 0.636), as well as between the amount of rain and the types and areas of vegetation in the study area, as the correlation values ​​were inverse with the weak and very weak vegetation cover (-0.732, -0.461), respectively, while they were direct with the dense and very dense types. (0.555, 0.848), which indicates the clear impact of rain change and fluctuation on the environment in general in the study area