Location: Water Management and Systems ResearchTitle: Would it help? Distributed Measurements in a Small Agricultural Catchment Support Spatial Complexity of Soil Hydrologic Modeling
|Erskine, Robert - Rob|
|KIPKA, HOLM - Colorado State University|
|DAVID, OLAF - Colorado State University|
|BARNARD, DAVID - US Department Of Agriculture (USDA)|
Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 8/8/2019
Publication Date: 11/9/2019
Citation: Green, T.R., Erskine, R.H., Kipka, H., Lighthart, N.P., Nezat, C.J., Edmunds, D.A., David, O., Barnard, D., Douglas-Mankin, K.R. 2019. Would it help? Distributed Measurements in a Small Agricultural Catchment Support Spatial Complexity of Soil Hydrologic Modeling. ASA-CSSA-SSSA Annual Meeting Abstracts.
Technical Abstract: Soil hydraulic properties that control water storage and flow rates can vary dramatically in space, and surface layers vary temporally due to management events, reconsolidation and biological activity. We explore the model spatial resolution and calibration detail needed to estimate available data using three different spatial resolutions in the Agricultural Ecosystems Services (AgES) model, each with five levels of spatial complexity in calibrated soil parameters from homogeneous to fully three-dimensional. At our dryland cropped field site in northern Colorado, space-time measurements across rolling terrain of soil moisture and surface runoff are essential to inform more complex model calibration and spatial scaling of soil moisture. Complex calibrations across higher-resolution simulations provide better moisture dynamics at different landscape positions, but all levels of spatial complexity scale up to capture similar field-scale dynamics of soil moisture. A model component of temporal changes in soil porosity and saturated hydraulic conductivity is used to simulate effects of tillage and soil consolidation related to rainfall. Interactions between spatial and temporal parameters and processes will be discussed. Finally, we highlight the value of long-term measurements of high-resolution soil moisture and catchment runoff to support complex simulations of surface hydrology and soil moisture dynamics.