Author(s): Clemens Weissteiner; Johann Peter Rauch; Johanna Jalonen; Juha Jarvela
Linked Author(s): Juha Järvelä
Keywords: Vegetative hydraulics; Ecological engineering; Woody riparian vegetation; Tree structure; Plant model; Parameterization; Projected area; Porosity
Abstract: Reliable determination of resistance exerted by trees on flow calls for physically based characterization of complex plant structure. This paper investigates the structural composition of four common riparian species (Alnusglutinosa, Betulapendula, Betulapubescens, Salixcaprea). For this purpose, 3D tree models were constructed by digitising twenty 0. 9-3. 3 m tall specimens on branch level in leafless condition. Three porosity definitions were explored to derive further information on the physical configuration of the trees. Branches contributed on average 55-60% to the total projected area. It was shown that the basal diameter could be used to predict the total projected area. However, a non-linear vertical distribution of the total projected area was found for taller (>~2m), branch dominated specimens of Alnusglutinosa and Salix caprea. Finally, it was concluded that detailed spatial-structural analyses of complex riparian trees provide valuable information for improving the estimation of vegetative flow resistance.
Year: 2013