Details zur Publikation

Kategorie Textpublikation
Referenztyp Zeitschriften
DOI 10.1029/2020WR029094
Lizenz creative commons licence
Titel (primär) Catchment functioning under prolonged drought stress: tracer‐aided ecohydrological modelling in an intensively managed agricultural catchment
Autor Yang, X.; Tetzlaff, D.; Soulsby, C.; Smith, A.; Borchardt, D.
Quelle Water Resources Research
Erscheinungsjahr 2021
Department ASAM
Band/Volume 57
Heft 3
Seite von e2020WR029094
Sprache englisch
Topic T5 Future Landscapes
Keywords Ecohydrological functioning; drought stress; tile drainage; Tracer‐aided modelling; stable isotopes of water and water ages; multi‐criteria calibration
Abstract High spatial heterogeneity of catchment properties enhances the variability of ecohydrological responses to changing natural and anthropogenic conditions, like the European‐wide droughts in 2018‐2019. Based on new adaptations of a tracer‐aided, process‐based ecohydrological model (EcH2O‐iso), we investigated drought‐induced nonstationary ecohydrological behaviour in a small agricultural headwater catchment (1.44 km2) in central Germany. Multiple environmental time‐series helped inform various aspects of catchment functioning that have been impacted by agricultural activity and changing climate conditions, and helped to further constrain model calibration. Multi‐criteria calibration showed that data collected during drought years were highly informative in reproducing the changes in stream water dynamics. Further, inclusion of urn:x-wiley:00431397:media:wrcr25185:wrcr25185-math-00012H and urn:x-wiley:00431397:media:wrcr25185:wrcr25185-math-000218O data were valuable for reducing model uncertainty and increasing confidence in simulations of green‐ and blue‐water flux partitioning and storage‐flux‐age interactions. Using the best‐performing calibrations, we further analyzed the high spatiotemporal variability of internal ecohydrological processes and the varying responses of fluxes and associated water ages to prolonged drought stress. Under drought conditions, modelled stream runoff contributed from deeper, older storages increased significantly after a particularly wet season, resulting in a sharp increase in stream water age. Unlike relatively minor changes in soil evaporation, seasonally typical transpiration fluxes were initially maintained in April‐June but dramatically decreased as the drought further developed in July‐September. Importantly, the tracer‐based transpired water age was much older after April, providing a potential indicator of drought impacts and the need for precautionary management responses. Our findings are important for similar agricultural headwater ecosystems in other drought‐sensitive regions.
dauerhafte UFZ-Verlinkung
Yang, X., Tetzlaff, D., Soulsby, C., Smith, A., Borchardt, D. (2021):
Catchment functioning under prolonged drought stress: tracer‐aided ecohydrological modelling in an intensively managed agricultural catchment
Water Resour. Res. 57 (3), e2020WR029094 10.1029/2020WR029094