2026-04-13T18:26:24Zhttps://recercat.cat/oai/request
oai:recercat.cat:10256/271742025-09-05T23:19:04Zcom_2072_452955com_2072_2054col_2072_453077
RECERCAT author Córdoba-Ariza, Paula Gabriela author Batalla, Ramon J. author Gutiérrez Provecho, Carmen author Sabater, Sergi author Mas-Pla, Josep 2025-09-05T23:19:03Z 2025-09-05T23:19:03Z 2025-06-23 http://hdl.handle.net/10256/27174 Climate change, land use, and resource exploitation increasingly threaten river hydrology and water quality, leading to scarcity. Non-perennial or intermittent rivers are vulnerable systems characterised by highly variable flows. While recent research has advanced understanding of their natural variability, integrating the complex effects of multiple human impacts at the basin scale remains challenging. Aiming to improve this understanding and supporting effective management, this study uses end-member mixing analysis (EMMA) to identify streamflow sources in an intermittent Mediterranean river network, based on hydrochemical data from 23 sites over 14 monthly surveys and potentiometric data from six shallow wells. The analysis identifies three main contributors to streamflow: headwater runoff, groundwater baseflow from aquifers and hillslopes and treated wastewater. Their relative contributions varied spatially and seasonally. Upstream of urban areas, headwater runoff dominated (71%), while in the central catchment, groundwater contributed 15%-75%. Downstream of industrial areas, contributions were more balanced: 35% runoff, 27% groundwater and 38% wastewater. Alluvial groundwater was more important in small upstream subbasins in terms of maintaining the connectivity of the streamflow, whereas groundwater contribution from deeper aquifers dominated in lower reaches. EMMA results also highlighted discrepancies with point potentiometric data, emphasising the limitations of local measurements for understanding basin-scale hydrology. Under future climate scenarios, reduced headwater runoff and groundwater storage are expected to lower baseflow, increasing reliance on treated but lower-quality wastewater to sustain streamflow. This highlights the need for long-term monitoring and management, with a focus on protecting baseflow sources and improving wastewater quality to ensure water sustainabilityThis work was supported by the European Union, MCIU/AEI/10.13039/501100011033/EU, European Social Fund, Generalitat de Catalunya, Centres de Recerca de Catalunya and Ministerio de Ciencia, Innovación y UniversidadesOpen Access funding provided thanks to the CRUE-CSIC agreement with Wiley Reconeixement-NoComercial 4.0 Internacional http://creativecommons.org/licenses/by-nc/4.0 info:eu-repo/semantics/openAccess Hidrologia Cursos d'aigua Hydrology Rivers Cabal (Hidrologia) Streamflow Conques hidrogràfiques Watersheds Streamflow Generation Processes and Stream Intermittency in a Mediterranean Basin: Insights From End-Member Mixing Analysis info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion peer-reviewed