Spatial Variation Analysis of Soil Aridity In Al-Madain District Using The NDVI And HDWI Indices

Abstract

This study aimed to detect and analyze soil aridity in the Al-Madain district using remote sensing and geographic information systems (GIS) technologies for the years 2016–2025. The study employed the Normalized Difference Vegetation Index (NDVI) and applied the vegetation cover index equation, analyzing the results spatially using several methodologies relevant to the study's subject matter. The Normalized Difference Water Index (HDWI) was also used. The study aimed to demonstrate changes in soil moisture in the Al-Madain district. To achieve this objective, a descriptive-analytical approach to satellite imagery was used to track and spatially analyze these changes. Specifically, satellite imagery captured by Landsat-8 in 2016 and Landsat-8 in 2025 was analyzed using ArcGIS 10.8 software. The study revealed a clear change in soil moisture during the study period. The results showed a clear change in soil moisture during this period. The vegetation cover was assessed according to the NDVI index. We find an increase in barren lands, as the northern region, represented by Al-Nahrawan and Al-Wahda districts, has large parts of it devoid of vegetation cover due to urban expansion and the increase in built-up areas at the expense of agricultural lands. Meanwhile, we find that the southern and southwestern parts are dense with vegetation cover. The amount of vegetation cover did not increase in 2025 compared to 2016. This reduction in vegetation cover will raise the surface temperature and then decrease soil moisture.