Wave dissipation by flexible vegetation

被引:51
作者
Riffe, Kassi C. [1 ]
Henderson, Stephen M. [1 ]
Mullarney, Julia C. [2 ]
机构
[1] Washington State Univ, Sch Earth & Environm Sci, Vancouver, WA 98686 USA
[2] Univ Waikato, Dept Earth & Ocean Sci, Hamilton 3240, New Zealand
关键词
WIND-WAVES; FLOW; EMERGENT; MARSH;
D O I
10.1029/2011GL048773
中图分类号
P [天文学、地球科学];
学科分类号
07 ;
摘要
Dissipation of waves propagating through natural salt marsh vegetation was about half the dissipation expected for rigid vegetation. This low dissipation was predicted by a theoretical model that accounts for bending of vegetation motions. A transect of 3 pulse-coherent Acoustic Doppler Profilers recorded water velocity and pressure (at 8 Hz) within the dense (650 stems/m(2)) canopy of semi-flexible single-stem vegetation (Schoenoplectus americanus). Most wave energy (56-81%) was dissipated within 19 m of the marsh edge. Two dissipation models, the first assuming rigid vegetation, and the second simulating wave-forced vegetation motion using the theory for bending of linearly-elastic beams, were tested. After choosing optimal drag coefficients, both models yielded a good fit to the observed dissipation (skill score = 0.96-0.99). However, fitted drag coefficients for the rigid model (0.58-0.78) were below the range (0.98-2.2) expected for the observed Reynolds numbers (13-450) and canopy densities (accounting for interactions between stem wakes), whereas drag coefficients for the flexible model (0.97-1.6) were nearer the expected range, indicating that prediction of wave dissipation was improved by simulating vegetation motion. Citation: Riffe, K. C., S. M. Henderson, and J. C. Mullarney (2011), Wave dissipation by flexible vegetation, Geophys. Res. Lett., 38, L18607, doi:10.1029/2011GL048773.
引用
收藏
页数:5
相关论文
共 27 条
[21]   The effects of vegetation on longitudinal dispersion [J].
Nepf, HM ;
Mugnier, CG ;
Zavistoski, RA .
ESTUARINE COASTAL AND SHELF SCIENCE, 1997, 44 (06) :675-684
[23]  
TOLMAN HL, 1994, J PHYS OCEANOGR, V24, P994, DOI 10.1175/1520-0485(1994)024<0994:WWAMBB>2.0.CO
[24]  
2
[25]  
Zedler JB, 2001, BIOSCIENCE, V51, P1005, DOI 10.1641/0006-3568(2001)051[1005:DBWSMA]2.0.CO
[26]  
2
[27]   A numerical study of cylinders in waves and currents [J].
Zhou, CY ;
Graham, JMR .
JOURNAL OF FLUIDS AND STRUCTURES, 2000, 14 (03) :403-428