Abstract
Water resources are precious in arid and semi-arid areas such as the Wadis of Iran. To sustainably manage these limited water resources, the residents of the Iranian Wadis have been traditionally using several water use systems (WUSs) which affect natural hydrological processes. In this study, WUSs and soil and water conservation measures (SWCMs) were integrated in a hydrological model of the Halilrood Basin in Iran. The Soil and Water Assessment Tool (SWAT) model was used to simulate the hydrological processes between 1993 and 2009 at daily time scale. To assess the importance of WUSs and SWCMs, we compared a model setup without WUSs and SWCMs (Default model) with a model setup with WUSs and SWCMs (WUS-SWCM model). When compared to the observed daily stream flow, the number of acceptable calibration runs as defined by the performance thresholds (Nash-Sutcliffe efficiency (NSE)≥0.68, −25%≤percent bias (PBIAS)≤25% and ratio of standard deviation (RSR)≤0.56) is 177 for the Default model and 1945 for the WUS-SWCM model. Also, the average Kling-Gupta efficiency (KGE) of acceptable calibration runs for the WUS-SWCM model is higher in both calibration and validation periods. When WUSs and SWCMs are implemented, surface runoff (between 30% and 99%) and water yield (between 0 and 18%) decreased in all sub-basins. Moreover, SWCMs lead to a higher contribution of groundwater flow to the channel and compensate for the extracted water by WUSs from the shallow aquifer. In summary, implementing WUSs and SWCMs in the SWAT model enhances model plausibility significantly.
Highlights
Over-exploitation of water resources and water scarcity have become a worldwide and prevalent problem in most arid and semi-arid regions such as the Wadis in Iran (Voss et al, 2013)
water use systems (WUSs) and soil and water conservation measures (SWCMs) were successfully implemented into a hydrological model in the Halilrood Basin
Our results clearly show that there are differences in both model setups (Default model and WUS-SWCM model), which can be related to the implementation of the different measures
Summary
Over-exploitation of water resources and water scarcity have become a worldwide and prevalent problem in most arid and semi-arid regions such as the Wadis in Iran (Voss et al, 2013). Over the past centuries, traditional water use systems (WUSs) such as qanats (a slightly sloping tunnel constructed to accumulate and transfer water from the groundwater to the land surface), wells, springs and dams have been used by native residents to manage limited water resources (Motiee et al, 2006; Ouessar et al, 2009; Nasiri and Mafakheri, 2015). In a Wadi catchment, the amount of water which is extracted by these traditional water supply systems can significantly affect river runoff (Ouessar et al, 2009)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
