Abstract:
Background Preferential flow is the movement of water through specific pathways in soil rather than a more uniform flow through the soil structure. Because of soil heterogeneity, such as fractures, root channels, or wormholes, these preferential flow pathways frequently form. This fractal pattern can make it challenging to understand and describe the behavior of preferred flow routes. For accurate water and solute transport, it is need of hour to comprehend and describe the growth and evolution of preferential flow routes. Improvement in conventional models will be needed to capture preferential flow's complicated and nonlinear behavior.
Methods Four 120 cm×120 cm plots were chosen and a dye tracing experiment was carried out to confirm the solute and water's preferred flow patterns on four plots. Data was analyzed in Origin Lab to create 3D graphs and tables and Sketchup Pro-2021. The 50 litters solution of Brilliant Blue (5 g/L) and water were given to each plot. Each plot contained three vertical soil profiles of 150 cm deep, and the profile walls underwent extensive knife preparation. The Brilliant Blue was left on the surface for 24 h for the penetration in soil surface.
Results The results demonstrate that preferential flow is most prominent in the areas with minimal compaction and a preserved continuity of macro-pores. Conversely, the impact of compaction leads to a decrease in micro-porosity and weaker preferential flow patterns in compacted regions. Brilliant Blue reaches a maximum depth of 15.5 cm in the soil. The movement of flow connectivity patterns (FCP) depends on different factors like roots, pores, cracks, etc. The Brilliant Blue goes maximum depth where the roots are available. In this study, Brilliant Blue movement has been shown in three-dimensional way by using Sketch Pro software for a better understanding of it. Moreover, this study reveals how compaction and subsequent recovery processes influence soil's susceptibility to water flow and surface runoff. By presenting comprehensive 3D representations, this study offers a superior understanding of the creation and evolution of water flow channels.
Conclusions According to the water flow patterns discovered in this study, preferred flow is the strongest at the higher site free of compaction, where macro-pores continuity is preserved. Due to the compaction impact, the micro-porosity decreases, and it grows weaker on the lower side. This study enhances knowledge of preferential flow and its role in nutrient and water cycling within natural and agricultural ecosystems. The insights gained from this study can inform the development of improved management strategies for agricultural lands, facilitating sustainable and efficient water resource management.