Distinct Rainfall Interception Profiles among Four Common Pacific Northwest Tree Species

Forest tree canopies have a critical influence on water cycles through the interception of precipitation. Nevertheless, radial patterns canopy may vary interspecifically. We analyzed using catchments along transects underneath four common forest species (Acer macrophyllum, Alnus rubra, Pseudotsuga menziesii, and Thuja plicata) in Pacific Northwest over two years. Near center leaf-off season, was 51.6%–67.2% conifer only 20.1%–40.1% broadleaf species, declined to 19.9–29.9 for all near edge canopy. One deciduous (A. rubra) showed spatially uniform during period (19.9%–20.96%), while another varied from 23.1%–40.1%. Patterns were more pronounced leaf-on (under high vapor pressure deficit conditions), where conifers intercepted 36.5%–95.9% precipitation, depending position under Deciduous similarly 42.1%–67.7% rainfall, position. Total throughfall curvilinearly related amount rainfall centers trees but less so trees. Soil moisture predictably across within species. These data highlight interspecific differences patterns, with consequences soil moisture, hydrologic processes, ecosystem function.