Coastal Groundwater Flow and Associated Nutrient Transport into the Sea
نویسنده
چکیده
A numerical model is developed to examine coastal groundwater processes in a sandy beach, including the effects of tidal fluctuations, saltwater intrusion into an aquifer, and dynamics in unsaturated layers. The simulation results indicate: 1) ‘Local circulation’ is clearly formed in the aquifer near the shoreline owing mainly to tidal oscillations. 2) The circulation induces a landward bending profile of salinity, wherein saline seawater is present. 3) As land-derived freshwater discharge increases, the circulation cell decreases in size and finally almost disappears. Subsequently, the model is linked with the nutrient data sampled in the aquifer of the sandy beach, Hasaki, Japan, for estimating nutrient transport into the sea. The nutrient flux via groundwater seepage is considered to have a minor component of marine nutrient budget in the surf zone; river discharge dominates at this beach.
منابع مشابه
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