TY - JOUR
T1 - Flow interaction with dynamic vegetation patches: Implications for biogeomorphic evolution of a tidal landscape
AU - Vandenbruwaene, W.
AU - Temmerman, S.
AU - Bouma, T.J.
AU - Klaassen, P.C.
AU - De Vries, M.B.
AU - Callaghan, D.P.
AU - van Steeg, P.
AU - Dekker, F.
AU - Van Duren, L.A.
AU - Martini, E.
AU - Balke, T.
AU - Biermans, G.
AU - Schoelynck, J.
AU - Meire, P.
N1 - Reporting year: 2011
Metis note: 5016; CEME; RE
PY - 2011
Y1 - 2011
N2 - [1] Feedback between vegetation growth, water flow, and landform is important for the
biogeomorphic evolution of many landscapes, such as tidal marshes, alluvial rivers, and
hillslopes. While experimental studies often focus on flow reduction within static
homogeneous vegetation, we concentrate on flow acceleration around and between
dynamically growing vegetation patches that colonize an initially bare landscape, with
specific application to Spartina anglica, a pioneer of intertidal flats. Spartina patches were
placed in a large-scale flow facility of 16 × 26 m, simulating the growth of two vegetation
patches by increasing the patch diameter (D = 1–3 m) and decreasing the interpatch
distance (d = 2.3–0 m). We quantified that the amount of flow acceleration next to
vegetation patches, and the distance from the patch where maximum flow acceleration
occurs, increases with increasing patch size. In between the patches, the accelerated flow
pattern started to interact as soon as D/d ≥ 0.43–0.67. As the patches grew further, the
flow acceleration increased until D/d ≥ 6.67–10, from which the flow acceleration
between the patches was suppressed, and the two patches started to act as one. These
findings are in accordance with theory on flow around and between nonpermeable
structures; however, the threshold D/d values found here for permeable vegetation patches
are higher than those for nonpermeable structures. The reported flow interactions with
dynamic vegetation patches will be essential to further understanding of the larger-scale
biogeomorphic evolution of landscapes formed by flowing water, such as tidal flats,
floodplain rivers, and hillslopes.
AB - [1] Feedback between vegetation growth, water flow, and landform is important for the
biogeomorphic evolution of many landscapes, such as tidal marshes, alluvial rivers, and
hillslopes. While experimental studies often focus on flow reduction within static
homogeneous vegetation, we concentrate on flow acceleration around and between
dynamically growing vegetation patches that colonize an initially bare landscape, with
specific application to Spartina anglica, a pioneer of intertidal flats. Spartina patches were
placed in a large-scale flow facility of 16 × 26 m, simulating the growth of two vegetation
patches by increasing the patch diameter (D = 1–3 m) and decreasing the interpatch
distance (d = 2.3–0 m). We quantified that the amount of flow acceleration next to
vegetation patches, and the distance from the patch where maximum flow acceleration
occurs, increases with increasing patch size. In between the patches, the accelerated flow
pattern started to interact as soon as D/d ≥ 0.43–0.67. As the patches grew further, the
flow acceleration increased until D/d ≥ 6.67–10, from which the flow acceleration
between the patches was suppressed, and the two patches started to act as one. These
findings are in accordance with theory on flow around and between nonpermeable
structures; however, the threshold D/d values found here for permeable vegetation patches
are higher than those for nonpermeable structures. The reported flow interactions with
dynamic vegetation patches will be essential to further understanding of the larger-scale
biogeomorphic evolution of landscapes formed by flowing water, such as tidal flats,
floodplain rivers, and hillslopes.
U2 - 10.1029/2010JF001788
DO - 10.1029/2010JF001788
M3 - Article
VL - 116
JO - Journal of Geophysical Research
JF - Journal of Geophysical Research
SN - 0148-0227
M1 - F01008
ER -