Fatemeh Zahra Takin - Department of Environmental Sciences, Faculty of Sciences, University of Zanjan, Iran.
Younes Khosravi - Department of Environmental Sciences, Faculty of Sciences, University of Zanjan, Iran.
Abbasali Zamani - Department of Environmental Sciences, Faculty of Sciences, University of Zanjan, Iran.

Background: This study was conducted to investigate the relationship between land use changes and physicochemical characteristics of groundwater in the Dalaki watershed in Bushehr province, from ۲۰۰۶ to ۲۰۱۶. Methods: In this study, changes in the amounts of chlorine, calcium, sodium, sulfate, and total dissolved solids were investigated. In the first step, the spatial relationships of the aforementioned parameters were evaluated and the optimal models were selected for mapping. Then, using Landsat satellite images, the land use classification was done. Finally, the relationships between land use changes and the physicochemical characteristics of groundwater were surveyed. Results: According to the analysis of the results, the highest concentration of groundwater in the studied years was observed in rainfed agriculture, palm groves and orchards land uses. Conclusion: A significant relationship can be established between agricultural uses and the increase in the concentration of groundwater physicochemical characteristics. In other words, agricultural use caused groundwater resources salinity and reduced their quality. Because of the vastness of land use, a large amount of groundwater is taken to irrigate crops. Moreover, rainfed agriculture increased and decreased the number of quality characteristics, however using planting palm trees only increased them.

Groundwater, Mapping, Dalaki watershed, Classification, Land use