Articles | Volume 20, issue 8
Research article
01 Aug 2016
Research article |  | 01 Aug 2016

Assessing land–ocean connectivity via submarine groundwater discharge (SGD) in the Ria Formosa Lagoon (Portugal): combining radon measurements and stable isotope hydrology

Carlos Rocha, Cristina Veiga-Pires, Jan Scholten, Kay Knoeller, Darren R. Gröcke, Liliana Carvalho, Jaime Anibal, and Jean Wilson

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Cited articles

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Short summary
We combine radon and stable isotopes in water to determine total submarine groundwater discharge (SGD) in the Ria Formosa and discriminate its component modes. We show that tidal action filters the entire water volume in the lagoon through local beaches 3.5 times a year, driving an estimated 350Ton nitrogen/year into the system. Conversely, fresh groundwater is discharged into the lagoon only occasionally, adding ~ 61 Ton nitrogen/year, but is capable of driving new production in the system.