Author(s): Jochen Aberle; Juha Jarvela; Thomas Schoneboom; Andreas Dittrich
Keywords: No Keywords
Abstract: Most studies into the estimation of flow resistance of emergent vegetation have been carried out under idealised conditions using cylindrical roughness elements, regular element spacing, etc. However, natural vegetation differs substantially from these artificial arrangements and adequate assessment of flow resistance requires the consideration of various plant specific parameters. Although this fact has been acknowledged, there exists only a limited number of approaches in which plant specific properties are directly considered. This paper discusses parameters and methods for the estimation of flow resistance due to emergent vegetation. Selected approaches were tested using data previously published in the literature and data obtained from experiments carried out by the authors. Plant types included artificial rigid cylindrical elements and artificial flexible vegetation. Recommendations were provided on potential further developments that take into account important plant characteristic features such as foliation and parameters derived from plant allometry.