Author(s): Finna Fitriana; Virginia Stovin; Ian Guymer
Linked Author(s): Ian Guymer
Keywords: No Keywords
Abstract: Vegetation significantly affects solute transport and mixing within open-channel flows. However, most studies simplify vegetation into uniform cylinder arrays, overlooking the hydrodynamic complexity introduced by realistic plant forms. This study quantifies the influence of foliated branches on longitudinal dispersion and flow resistance through controlled laboratory experiments. Tracer studies were conducted in a 12.5 m long, 0.30 m wide flume using artificial foliated emergent vegetation and a cylinder control. Longitudinal dispersion coefficients (Dx) and Manning’s roughness (n) were derived from tracer curve fitting and hydraulic measurements, respectively. Results show that Dx increases linearly with mean velocity and is significantly higher in branched vegetation than in the single-stem and cylinder configurations, while n decreases with velocity but remains larger in denser setups. These findings highlight the strong coupling between vegetation morphology, resistance, and mixing, supporting improved representation of vegetation effects in one-dimensional water quality models.
Year: 2026