Linkages between submarine groundwater systems and the environment

Submarine groundwater discharge (SGD) has been recognized as an important source of freshwater discharge into the ocean. Different approaches are used to estimate the SGD magnitude. Principal methods include, first, direct measurement using manual or automated seepage meters, second, chemical tracers, and third, hydrogeologic modeling. Submarine groundwater studies reveal that SGD provides important fluxes of nutrients, carbon, and trace metals to coastal waters that have the potential to impact the chemical budget of coastal water. Apart from the amounts of nutrients (N, P, and Si)/carbon entering the coastal ocean through SGD, it is also important to evaluate the potential effect of SGD on the Redfield ratio, because this ratio determines which nutrient is limiting phytoplankton growth. To pursue detailed SGD studies, an independent discipline would facilitate more progress.