Submarine groundwater discharge

Submarine groundwater discharge (SGD) is a hydrological process which commonly occurs in coastal areas. It is described as submarine inflow of fresh-, and brackish groundwater from land into the sea. Submarine groundwater discharge is controlled by several forcing mechanisms, which cause a hydraulic gradient between land and sea.[1] Considering the different regional settings the discharge occurs either as (1) a focused flow along fractures in karst and rocky areas, (2) a dispersed flow in soft sediments, or (3) a recirculation of seawater within marine sediments. Submarine groundwater discharge plays an important role in coastal biogeochemical processes and hydrological cycles such as the formation of offshore plankton blooms, hydrological cycles, and the release of nutrients, trace elements and gases.[2][3][4][5] It affects coastal ecosystems and has been used as a freshwater resource by some local communities for millennia.[6]

  1. ^ William C.Burnett, Bokuniewicz, Henry, Huettel, Markus, Moore, Willard S., Taniguchi, Makoto. "Groundwater and pore water inputs to the coastal zone", Biogeochemistry, Volume 66, 2003, Page 3–33.
  2. ^ Claudette Spiteri, Caroline P. Slomp, Matthew A. Charette, Kagan Tuncay, Christof Meile. "Flow and nutrient dynamics in a subterranean estuary (Waquoit Bay, MA, USA): Field data and reactive transport modeling", Geochimica et Cosmochimica Acta, Volume 72, Issue 14, 15 July 2008, Pages 3398–3412.
  3. ^ Caroline P. Slomp, Philippe Van Cappellen. "Nutrient inputs to the coastal ocean through submarine groundwater discharge: controls and potential impact", Journal of Hydrology, Volume 295, Issues 1–4, 10 August 2004, Pages 64–86.
  4. ^ Moore, Willard S. (1996). "Large groundwater inputs to coastal waters revealed by 226Ra enrichments". Nature. 380 (6575): 612–614. doi:10.1038/380612a0. S2CID 4249682.
  5. ^ Matthew A. Charette, Edward R. Sholkovitz. "Trace element cycling in a subterranean estuary: Part 2. Geochemistry of the pore water", Geochimica et Cosmochimica Acta, Volume 70, Issue 4, 15 February 2006, Pages 811–826.
  6. ^ Moosdorf, N.; Oehler, T. (2017-08-01). "Societal use of fresh submarine groundwater discharge: An overlooked water resource". Earth-Science Reviews. 171: 338–348. Bibcode:2017ESRv..171..338M. doi:10.1016/j.earscirev.2017.06.006. ISSN 0012-8252.