We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Direct Observation of Hillslope Scale StorAge Selection Functions in Experimental Hydrologic Systems: Geomorphologic Structure and Preferential Discharge of Old Water.
- Authors
Kim, Minseok; Volkmann, Till H. M.; Wang, Yadi; Meira Neto, Antonio A.; Matos, Katarena; Harman, Ciaran J.; Troch, Peter A.
- Abstract
Spatially integrated water transport dynamics at the hillslope scale have rarely been observed directly, and underlying physical mechanisms of those dynamics are poorly understood. We present time‐variable transit time distributions and StorAge Selection (SAS) functions for a 28 days tracer experiment conducted at the Landscape Evolution Observatory, Biosphere 2, the University of Arizona, AZ, USA. The observed form of the SAS functions is concave, meaning that older water in the hillslope was preferentially discharged than younger water. The concavity is, in part, explained by the relative importance of advective and diffusive water dynamics and by the geomorphologic structure of the hillslopes. A simple numerical examination illustrates that, for straight plan‐shaped hillslopes, the saturated zone SAS function is concave when the hillslope Péclet (Pe) number is large (and thus when the advective water dynamics are more pronounced). We also investigated the effect of hillslope planform geometry on the saturated zone SAS function using a model and found that the more convergent the plan shape is, the more concave the SAS function is. A numerical examination indicates that the unsaturated zone SAS function is concave for straight and convergent hillslopes when the soil thickness is uniform. The concavity of those subcomponent SAS functions signifies that the hillslope scale SAS function is concave for straight or convergent plan shape hillslopes when the hillslope Pe number is high. Key Points: We present the StorAge Selection (SAS) functions observed in hillslope scale experimental systemsThe observed SAS functions are concave, meaning that water leaving the systems is mainly older stored waterPredominance of advective water dynamics and the geomorphologic structure of the hillslopes explain the concavity of the SAS functions
- Subjects
UNIVERSITY of Arizona; GEOMORPHOLOGY; CONCAVE functions; SOIL depth; STORAGE; BIOSPHERE
- Publication
Water Resources Research, 2022, Vol 58, Issue 3, p1
- ISSN
0043-1397
- Publication type
Article
- DOI
10.1029/2020WR028959