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Key research themes
1. How do fluvial sedimentary patterns and instabilities govern the morphodynamics of river channels at multiple spatial scales?
This research area focuses on understanding the formation and evolution of sedimentary patterns and bedform instabilities in fluvial environments, encompassing micro- to macro-scale structures. These patterns control sediment transport dynamics, channel morphology, and habitat complexity, which are essential for interpreting river response to environmental forcing and for predicting river behavior under changing climatic and anthropogenic influences.
Key finding: This paper differentiates fluvial patterns into free patterns arising from boundary instabilities (such as bed forms and channel planforms) and forced patterns driven by hydrological factors (erosional/depositional zones). It... Read more
Key finding: Offering a comprehensive review, this paper categorizes fluvial instabilities into micro-scale (e.g., ripples, dunes), meso-scale (bars), and macro-scale (meandering channels) based on physical scales and mechanisms. It... Read more
Key finding: Utilizing two-dimensional hydrodynamic modeling, this study delineates eight distinct morphological units (MUs) in a gravel–cobble bed river, demonstrating that pool-riffle units are part of a more complex mosaic of landforms... Read more
2. How does vegetation influence fluvial hydraulics and habitat complexity in river channels?
This theme investigates the hydrodynamic effects of submerged and emergent vegetation on flow characteristics, sediment transport, and instream habitat complexity. Vegetation is a critical biotic factor affecting flow resistance, turbulence, and patterns of sediment retention. Understanding these interactions is vital for river restoration, management of aquatic ecosystems, and conservation of biodiversity in fluvial environments.
Key finding: Through laboratory experiments and numerical simulations, this research quantifies how submerged and emergent vegetation patches alter velocity profiles, Reynolds stresses, and turbulence intensities in channels. Key findings... Read more
Key finding: This experimental study shows that the addition of boulders significantly increases hydraulic habitat complexity metrics, such as kinetic energy gradients and recirculation metrics, which are indicative of biologically... Read more
Key finding: Using flume experiments, this study disentangles the effects of vegetation structural properties—such as density, height, structural diversity, and leaf pubescence—on sediment retention on plant surfaces and sediment... Read more
3. What controls fluoride concentration distributions in alluvial and phreatic aquifers in semiarid to arid fluvial environments?
Elevated fluoride levels in groundwater of alluvial aquifers pose significant health risks such as dental and skeletal fluorosis. This research theme focuses on delineating geochemical, hydrological, and lithological factors influencing fluoride concentrations, including well depth, aquifer matrix composition, groundwater chemistry (pH, alkalinity), and residence time. Understanding these controls informs risk assessment and groundwater management in fluvial settings with fluoride contamination.
Key finding: Analyzing 18 wells in the Meoqui-Delicias aquifer, this study found a significant negative correlation (r = -0.52, p < 0.05) between fluoride concentration and well depth, indicating higher fluoride levels in shallow wells.... Read more
Key finding: This paper identifies a geochemical environment characterized by high pH, alkaline water, and low calcium concentrations as controlling factors for fluoride mobility and accumulation in an unconfined aquifer. Multivariate... Read more