Parameterizing an aeolian erosion model for rangelands

Authors: EDWARDS, BRANDON - New Mexico State University; WEBB, NICHOLAS - New Mexico State University; Van Zee, Justin; Courtright, Ericha; COOPER, BRADLEY - New Mexico State University; METZ, LORI - Natural Resources Conservation Service (NRCS, USDA); Herrick, Jeffrey - Jeff; OKIN, GREGORY - University Of California (UCLA); DUNIWAY, MICHEAL - Us Geological Survey (USGS); Tatarko, John; TEDELA, NEGUSSIE - Bureau Of Land Management; Newingham, Beth; Pierson Jr, Frederick; Toledo, David; Van Pelt, Robert - Scott

Submitted to: Aeolian Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/27/2021
Publication Date: 12/13/2021
Citation: Edwards, B.L., Webb, N.P., Van Zee, J.W., Courtright, E.M., Cooper, B.F., Metz, L., Herrick, J.E., Okin, G., Duniway, M.C., Tatarko, J., Tedela, N., Newingham, B.A., Pierson Jr, F.B., Toledo, D.N., Van Pelt, R.S. 2021. Parameterizing an aeolian erosion model for rangelands. Aeolian Research. 54.Article 100769. https://doi.org/10.1016/j.aeolia.2021.100769.
DOI: https://doi.org/10.1016/j.aeolia.2021.100769

Interpretive Summary: Researchers with the USDA-ARS Jornada Experimental Range and Long-Term Agroecosystem Research Network (LTAR) along with other colleagues have developed a new wind erosion and dust emission model. The model was calibrated for rangelands using 2015–2019 data from the National Wind Erosion Research Network (NWERN). This paper presents the Aeolian EROsion (AERO) wind erosion and dust emission model and results of the calibration for rangelands. Results show a one-to-one relationship between sediment transport predictions and observations, which indicates that environmental indicators used to condition the model were appropriate and that the model adequately represents windblown sediment transport processes. Model estimates provide value for land management and assessment of conservation practices by encapsulating spatial, intra- and inter-annual variability in windblown sand and dust potential. AERO provides robust assessments suitable for assessing land health, air quality, and the effectiveness of conservation practices.

Technical Abstract: Aeolian processes are fundamental to arid and semi-arid ecosystems, but modeling approaches are poorly developed for assessing impacts of management and environmental change on sediment transport rates over relevant spatial and temporal scales. For model estimates to provide value in this context, estimates of sediment flux that encapsulate spatial, intra- and inter-annual variability are needed. It is important to quantify and communicate transparent estimates of model uncertainty to users. Here, we present the Aeolian EROsion (AERO) wind erosion and dust emission model for rangelands and parameterization using a Generalized Likelihood Uncertainty Estimation framework (GLUE). Modeled horizontal sediment flux was calibrated using data from five grassland and shrubland sites from the National Wind Erosion Research Network. Observations of wind speed, vegetation height, canopy gap length, and bare soil cover were used to condition simulations for 10,000 independently sampled parameter sets. Results were compared to observations from 44 sediment transport observation periods to produce likelihood distributions of the simulations. Selected rejection criteria resulted in 453 acceptable parameter sets and uncertainty was estimated for 90% prediction bounds using quantiles of ranked estimates from acceptable models. Results show good agreement for individual sampling periods across sites, with few observations falling outside of the 90% prediction bounds and a one-to-one relationship between median predictions and observations. Further, combined distributions of flux estimates from all sample periods for a given site closely approximate the probability of observing a given flux at that site, suggesting AERO effectively represents spatiotemporal variability in aeolian transport rates and provides robust assessments suitable for assessing land health, air quality, and the effectiveness of conservation practices.