Preferential and non-uniform flows are widespread features of natural and engineered porous media and may arise from biotic factors, such as roots and soil fauna, abiotic processes including wetting-drying and freeze-thaw cycles, lithological and structural heterogeneity, as well as anthropogenic activities such as tillage, cultivation practices and landforms construction. Preferential and non-uniform flows can strongly affect water redistribution and the transport of solutes, nutrients and contaminants. Preferential flow pathways may develop and interact over a wide range of spatial scales from the pore scale to soil profiles and entire catchments, while their occurrence and relevance may vary over time, from individual hydrological events to seasonal and interannual dynamics.
This session welcomes experimental, theoretical and modeling studies aimed to improving the understanding, characterization and quantification of preferential and non-uniform flows in porous media across scales. Contributions are welcome on:
• Understanding the geometry, connectivity, formation and temporal dynamics of flow in fissures, fractures, macropores and other preferential flow pathways;
• Understanding the role of physical, biological and geochemical processes in the dynamics of macropores and fracture networks;
• Experimental methods for characterizing heterogeneous pore structures and hydraulic properties, including tracer, imaging, and infiltration-based approaches;
• Conceptual, analytical and numerical approaches for modelling preferential water flow from pore and pedon scales to hillslopes, catchments, and landscapes;
• Approaches linking measurements and models and addressing spatial heterogeneity, temporal variability, and scale transitions in preferential flow processes.
• Development of non-invasive and geophysical techniques, including electrical resistivity tomography and ground penetrating radar for identifying and monitoring preferential flow pathways in porous media.