Feedbacks between riparian vegetation and hydrogeomorphic processes in sand-bed rivers

Riparian vegetation communities co-evolve with hydrogeomorphic processes in dynamic river systems. Feedbacks between plants and channel morphology vary spatially and temporally but are especially strong when plants are small enough to be scoured or buried during floods but large enough to influence flow hydraulics and sediment transport within channels and on bars. This NSF-funded project (EAR-1024820) coupled laboratory flume experiments at the St. Anthony Falls Laboratory at the University of Minnesota and UC Berkeley with field investigations on the Bill Williams River (AZ) in the Colorado Basin to quantify the effect of native (willow, cottonwood) versus non-native (Tamarisk) plants on flow and sediment transport, as well as the reciprocal ecological effects on plant removal via scour and burial. Through this work, we can better understand feedbacks at scales ranging from individual plants to channel reaches, with the goal of improving management of arid-land river systems.

Collaborators:

• Andrew Wilcox (Univ. of Montana)
• Anne Lightbody (Univ. of New Hampshire)
• Pat Shafroth (USGS)
• Leonard Sklar (California State University, San Francisco)

Related publications and presentations: (* indicates student contributors)

Kui, L.*, J.C. Stella, P.B. Shafroth, P.K. House, A.C. Wilcox. 2017. The long-term legacy of geomorphic and riparian vegetation feedbacks on the dammed Bill Williams River, Arizona, USA. Ecohydrology DOI: 10.1002/eco.1839

Diehl, R.M., A.C. Wilcox, J.C. Stella, L. Kui*, L. Sklar, A. Lightbody. 2016. Fluvial sediment supply and pioneer woody seedlings as a control on bar-surface topography. Earth Surface Processes and Landforms DOI: 10.1002/esp.4017

Kui, L.* and J.C. Stella. 2016. Fluvial sediment burial increases mortality of riparian tree seedlings but induces compensatory growth response in survivors. Forest Ecology and Management, 366. DOI: 10.1016/j.foreco.2016.02.001

Bywater-Reyes, S.*, A.C. Wilcox, J.C. Stella, and A.F. Lightbody. 2015. Flow and scour constraints on uprooting of pioneer woody seedlings, Water Resources Research, 51. DOI:10.1002/2014WR016641

Manners, R., A.C. Wilcox, L. Kui*, A. Lightbody, J.C. Stella, L. Sklar. 2015. When do plants modify fluvial processes? Plant-hydraulic interactions under variable flow and sediment supply rates. Journal of Geophysical Research – Earth Surface. DOI:10.1002/2014JF003265

Kui, L.*, J.C. Stella, A. Lightbody, A.C. Wilcox. 2014. Ecogeomorphic feedbacks and flood loss of riparian tree seedlings in meandering channel experiments. Water Resources Research. 50, DOI: 10.1002/2014WR015719

Bendix, J., and J.C. Stella. 2013. Riparian Vegetation and the Fluvial Environment: A Biogeographic Perspective. In Treatise on Geomorphology 12: Ecogeomorphology (D. Butler and C. Hupp, Eds.). Elsevier, San Diego. DOI: 10.1016/B978-0-12-374739-6.00322-5 [pdf]