Understanding Surface Water Loss in the Zayandeh-Rud Basin, Iran: an interdisciplinary analysis of anthropogenic and climatic factors

In this study of the Zayandeh-Rud basin in Iran, we examined the interplay of anthropogenic and climatic factors on surface water resources from 1984 to 2021. Using remote sensing data, local data, and GIS analyses, we identified two anthropogenic drivers which are population and irrigated land, and two climatic drivers which are precipitation and temperature potentially affecting surface water extent. The QGIS software facilitated the masking of surface water and the analysis of key factors, offering comprehensive insights into the characteristics of the study area. By identifying linear trends and normalizing the data, we compared the Zayandeh-Rud basin with Iran and other adjacent basins to have a better judgment of potential factors that affected changes in surface water extent. Our findings reveal the emergence of meteorological droughts, challenging the notion that climate alone dictates water loss. The Koppen-Geiger climate classification underscores the substantial influence of human activities, particularly population growth and agricultural practices, on surface water dynamics. Our study underscores the need for more effective water management policies to address the complex challenges arising from both climatic and anthropogenic influences in the Zayandeh-Rud basin.