Title
Ecogeomorphic feedbacks and flood loss of riparian tree seedlings in meandering channel experiments
Document Type
Article
Publication Title
Water Resources Research
Publisher
American Geophysical Union Publications
Publication Date
10-23-2014
Volume
50
Disciplines
Earth Sciences
Abstract
During floods, fluvial forces interact with riparian plants to influence evolution of river morphology and floodplain plant community development. Understanding of these interactions, however, is constrained by insufficient precision and control of drivers in field settings, and insufficient realism in laboratory studies. We completed a novel set of flume experiments using woody seedlings planted on a sandbar within an outdoor meandering stream channel. We quantified effects on local sedimentation and seedling loss to scour and burial across realistic ranges of woody plant morphologies (Populus versus Tamarix species), densities (240 plants m-2 versus 24 m-2), and sediment supply (equilibrium versus deficit). Sedimentation was higher within Tamarix patches than Populus patches, reflecting Tamarix’s greater crown frontal area and lower maximum crown density. Plant dislodgement occurred rarely (1% of plants) and was induced in plants with shorter roots. Complete burial was most frequent for small Tamarix that occurred at high densities. Burial risk decreased 3% for Populus and 13% for Tamarix for every centimeter increment in stem height, and was very low for plants >50 cm tall. These results suggest that Tamarix are proportionally more vulnerable than Populus when small (<20 cm tall), but that larger plants of both species are resistant to both burial and scour. Thus, plant morphological traits and development windows must be considered in addition to physical drivers when designing process-based restoration efforts on regulated rivers such as flow releases to benefit native tree species.
Keywords
riparian vegetation, seedling mortality, burial, scour, Tamarix, Populus, flume
DOI
10.1002/2014WR015719
Rights
© 2014. American Geophysical Union. All Rights Reserved.
Recommended Citation
Kui, L., J. C. Stella, A. Lightbody, and A. C. Wilcox (2014), Ecogeomorphic feedbacks and flood loss of riparian tree seedlings in meandering channel experiments, Water Resour. Res., 50, doi:10.1002/2014WR015719.
Comments
An edited version of this paper was published by AGU. Copyright (2014) American Geophysical Union.