Urban Landscape Vegetation and Rainfall Canopy Interception:Through an Eco-Hydrological Lens

Urban eco-hydrology is a critical research field for sustainable urban development. Rapid urbanization has led to a significant expansion of impervious surfaces, profoundly altering urban hydrological processes. Vegetation canopy interception plays a key role in stormwater regulation and microclimate mitigation. Current research relies mainly on direct measurements, which face limitations in spatial scalability and high costs. Although models are widely used in natural ecosystems, like the revised Gash model, but their urban applications—especially in northern cities - remain limited, representing only 5.7% of relevant studies. To address these gaps, this study developed a multi-scale interception model based on the revised Gash model, incorporating planting configuration parameters for typical species in Beijing. The results demonstrate that interception capacity is significantly influenced by species traits, planting configuration, and rainfall intensity. Coniferous species consistently outperformed broadleaved species across all scenarios, with Juniperus chinensis L. exhibiting the highest interception (up to 18.46 mm under high rainfall intensity in 5-plant clusters). Interception increased with planting density, following the order: clump planting (5 plants) > clump planting (4 plants) > opposite planting > solitary planting. In mixed-species configurations, combinations involving high-interception species—such as Cedrus deodara. with Juniperus chinensis L. —achieved the highest interception (17.78 mm), significantly exceeding low-interception combinations such as Prunus persica 'Duplex'. with Prunus triloba. (8.13 mm). Sensitivity analysis revealed that evaporation rate (E) and canopy cover (C) were the most influential parameters under solitary planting, while canopy storage capacity (S) became increasingly important in dense planting configurations.This work enhances understanding of micro-scale hydrology and provides practical strategies for nature-based urban resilience, aiding vegetation optimization in green infrastructure (GI).