Effects of bedrock permeability on hillslope and riparian groundwater dynamics in a weathered granite catchment

Abstract

To investigate the effects of bedrock permeability on the linkage between hillslope and riparian groundwater in a weathered granite headwater catchment, the groundwater dynamics were studied using intensive hydrometric and tracer observations. Water flow from the hillslope, through the hillslope/riparian interface, and into the riparian zone consists of two components: saturated through flow on the soil‐bedrock interface during storms and groundwater flow within the permeable bedrock occurring year‐round, except during the driest season. Most of the water, which will contribute to the stream, infiltrates the largest part of the catchment and the hillslope area and recharges the deeper groundwater body. Therefore bedrock permeability is an important factor in determining the hillslope‐riparian linkage.