Bedrock Groundwater Catchment Area Unveils Rainfall‐Runoff Processes in Headwater Basins

Bedrock groundwater (BGW) has a contribution area that differs from of the surface watershed. To date, there been no analysis using BGW observations to determine what extent catchment influences runoff characteristics. This study determined water table, densely nested boring wells (61 in bedrock and three soil layer) drilled granitic basin (2.3 ha). Streamflow was also measured concurrently across entire watershed (F0) subwatersheds (F1 F6). The F3 accounted for 191% derived topography, reducing adjacent watersheds through cross-watershed flow. annual precipitation input baseflow volume highly correlated, indicating reflected actual effect layer more accurately than area. degree weathering showed table distributed along boundary CL–CM classes. estimated permeability CM class based on deep percolation rate suggests depth near is hydrological basement surface; this defines demonstrates concept provides an accurate prediction streamflow mountainous headwater basins are heavily governed by processes bedrock.