Future changes in the Dominant Source Layer of riparian lateral water fluxes in a subhumid Mediterranean catchment

JOURNAL OF HYDROLOGY

卷:595

Article

Ledesma, Jose L. J.^1,2,3  Ruiz-Perez, Guiomar⁴  Lupon, Anna²  Poblador, Silvia^5,6  Futter, Martyn N.³  Sabater, Francesc⁵  Bernal, Susana² 

[1] Karlsruhe Inst Technol KIT, Inst Geog & Geoecol, Reinhard Baumeister Pl 1, D-76131 Karlsruhe, Germany

[2] Spanish Natl Res Council CEAB CSIC, Ctr Adv Studies Blanes, Integrat Freshwater Ecol Grp, Acces Cala St Francesc 14, Blanes 17300, Spain

[3] Swedish Univ Agr Sci SLU, Dept Aquat Sci & Assessment, POB 7050, S-75007 Uppsala, Sweden

[4] Swedish Univ Agr Sci SLU, Dept Crop Prod Ecol, POB 7044, S-75007 Uppsala, Sweden

[5] Univ Barcelona, Dept Biol Evolut Ecol & Ciencies Ambientals, Av Diagonal 643, Barcelona 08028, Spain

[6] Univ Antwerp, Dept Biol, Res Grp Plants & Ecosyst, Univ Pl 1, B-2610 Antwerp, Belgium

关键词: Terrestrial-aquatic interface;    Hydrological connectivity;    Hydrological modelling;    Catchment biogeochemistry;    Mediterranean climate;    Environmental change;   

DOI  :  10.1016/j.jhydrol.2021.126014

来源: Elsevier

【 摘 要 】

The 'Dominant Source Layer' (DSL) is defined as the riparian zone (RZ) depth stratum that contributes the most to water and solute fluxes to streams. The concept can be used to explain timing and amount of matter transferred from RZs to streams in forest headwaters. Here, we investigated the potential impact of future climate changes on the long-term position of the DSL in a subhumid Mediterranean headwater catchment. We used the rainfall-runoff model PERSiST to simulate reference (1981-2000) and future (2081-2100) stream runoff. The latter were simulated using synthetic temperature, precipitation, and inter-event length scenarios in order to simulate possible effects of changes in temperature, rainfall amount, and rainfall event frequency and intensity. Simulated stream runoff was then used to estimate RZ groundwater tables and the proportion of lateral water flux at every depth in the riparian profile; and hence the DSL. Our simulations indicated that future changes in temperature and precipitation will have a similar impact on the long-term DSL position. Nearly all scenarios projected that, together with reductions in stream runoff and water exports, the DSL will move down in the future, by as much as ca. 30 cm. Shallow organic-rich layers in the RZ will only be hydrologically activated during sporadic, large rainfall episodes predicted for the most extreme inter-event length scenarios. Consequently, terrestrial organic matter inputs to streams will decrease, likely reducing catchment organic matter exports and stream dissolved organic carbon concentrations. This study highlights the importance of identifying vertical, hydrologically active layers in the RZ for a better understanding of the potential impact of future climate on lateral water transfer and their relationship with surface water quality and carbon cycling.

【 授权许可】

Free