Study of the impact of climate change on the fluctuation of water volume and level in the Al-Dalmaj Marsh Basin for the period from (2000-2025) based on modern geographical techniques

Abstract

Water bodies, including marshes, are among the landforms most sensitive to climate change. Variations in their qualitative, quantitative, and topographic characteristics provide clear evidence of climatic impacts observed globally and across different regions of Iraq in recent decades. Hor Al-Dalmaj represents one of the water bodies that has shown significant responses to climate change and environmental conditions during the period 2000–2025. Changes in water levels within Hor Al-Dalmaj Lake were monitored and quantified using remote sensing techniques and Geographic Information Systems through the analysis of Landsat satellite imagery for the years 2000, 2005, 2010, 2015, and 2025. This study aims to analyze the temporal and structural changes of the marsh using the Normalized Difference Water Index (NDWI) to extract water classes, assess change dynamics, and evaluate hydrological behavior under climate change. The results indicate a general trend toward shrinkage of the water surface area, accompanied by fluctuating change rates. Structural transformations were observed, including a decline in deep-water areas and an expansion of shallow water and dry land classes, reflecting hydrological responses to climate change and human pressures.