Grant: Research Tools and Instruments - Category 1 (<$150,000)

Decades of airflow and sand transport studies on coastal and desert sand dunes have provided high-quality empirical data on how different dune morphologies are created, develop their form and maintain mobility. Despite these advances, little is known about airflow and sand transport patterns on supply-limited, inland dune morphologies, particularly on parabolic dunes and blowouts. This is problematic because active inland dunes are critically important to biodiversity, yet little baseline information currently exists to help conserve and manage these valued ecosystem components. Specifically, the interactions between dune topography, vegetation, near-surface airflow and sand transport on supply-limited inland dunes are not well understood. Such interactions are known to exert major controls on dune mobility in coastal and desert environments via flow-form interactions and resulting secondary flow effects. However, no detailed investigation has been previously undertaken on supply-limited inland dunes to document these interactions. Results from my recent field studies in the Northern Great Plains (Hugenholtz & Wolfe, 2006; Hugenholtz et al., 2007) indicate clearly that high-resolution airflow and sand transport measurements would clarify flow-form interactions and secondary flow effects that control the development and mobility of supply-limited inland dunes. Resolving these characteristics will aid in the development of more comprehensive numerical and process-response models of inland dune dynamics. To this end, NSERC RTI funds are requested to purchase an innovative Wind Erosion Measurement System that will enable high-resolution, synchronized measurements of airflow and sand flux across active and partially stabilized parabolic dunes and blowouts. This system will be used as part of a corresponding NSERC Discovery Grant proposal to investigate relations between aeolian processes and dune mobility in the semi-arid portion of the Northern Great Plains.REFERENCES: Hugenholtz CH & SA Wolfe, 2006. Earth Surface Processes & Landforms 31: 1540-1557; Hugenholtz CH, Wolfe SA, Walker IJ & BJ Moorman, 2007. Geomorphology (in press).