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To reliably estimate water levels and velocities in vegetated rivers and floodplains, flow resistance models based on physical plant properties are advantageous. The purpose of this study is (1) to assess the suitable parameterization of woody riparian vegetation in estimating the drag forces, (2) to address the effect of plant scale on the drag estimates and reconfiguration, and (3) to evaluate the applicability of three recently developed flow resistance models. Experiments on four tree species in a towing tank together with detailed characterization of tree properties were carried out to establish a novel dataset. Despite the variability in the tree height (0.9 m–3.4 m), the stem, leaf and total areas proved to be suitable characteristic dimensions for estimating the flow resistance at different scales. Evaluations with independent data revealed that the tested models produced reasonable results. The performance of the models was controlled by the parameter values used rather than the model structure or the plant scale.

To reliably estimate water levels and velocities in vegetated rivers and floodplains, flow resistance models based on phys-ical plant properties are advantageous. The purpose of this study is (1) to assess the suitable parameterization of woody riparian veg-etation in estimating the drag forces, (2) to address the effect of plant scale on the drag estimates and reconfiguration, and (3) to evaluate the applicability of three recently developed flow resistance models. Experiments on four tree species in a towing tank to-gether with detailed characterization of tree properties were carried out to establish a novel dataset. Despite the variability in the tree height (0.9 m-3.4 m), the stem, leaf and total areas proved to be suitable characteristic dimensions for estimating the flow resistance at different scales. Evaluations with independent data revealed that the tested models produced reasonable results. The performance of the models was controlled by the parameter values used rather than the model structure or the plant scale.

Natural riparian vegetation generally presents a complex hydrodynamic behavior governed by plant morphology and flexibility. By contrast, hydrodynamic processes in partly vegetated channels are conventionally simulated by using simplified model vegetation, such as arrays of rigid cylinders. The aim of this study is to investigate the impacts of embedding natural plant features in the experimental simulation of flow in partly vegetated channels. Unique comparative experiments were carried out with both reconfiguring vegetation made of natural‐like shrubs and grasses, and with rigid cylinders. While the lateral distributions of flow properties presented a high similarity governed by the shear layer differential velocity ratio, the bulk vegetative drag, and the presence of large‐scale vortices, the flexibility‐induced mechanisms of natural‐like vegetation markedly affected the flow at the interface. Differences in plant morphology and spacing, and the dynamic motion of flexible foliated plants induced deeper vortex penetration into the vegetation. The normalized shear penetration was 6–10 times greater than observed for rigid cylinders, resulting in wider zones significantly exchanging momentum with the adjacent open water. The efficiency of lateral momentum transport for flexible foliated vegetation was up to 40% greater than the corresponding rigid cylinder case. Overall, the results indicated that improving the representativeness of model vegetation is a critical step toward the accurate simulation of hydrodynamic and transport processes in natural settings. Dynamically similar shear layers shared analogous lateral distributions of flow velocity and derived quantitiesHigher shear penetration within the vegetation was observed for flexible foliated plants in comparison to rigid cylindersVegetation morphology and flexibility were found to affect key exchange processes across the vegetated interface Dynamically similar shear layers shared analogous lateral distributions of flow velocity and derived quantities Higher shear penetration within the vegetation was observed for flexible foliated plants in comparison to rigid cylinders Vegetation morphology and flexibility were found to affect key exchange processes across the vegetated interface

This is the erratum to the article [JALONEN Johanna, JÄRVELÄ Juha, Journal of Hydrodynamics, 2014, 26(4)]. In pages 610 and 621 the drag coefficients are corrected.

In pages 610 and 621 the draf coefficients should be: