English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/21357
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:


An assessment of karstic submarine groundwater and associated nutrient discharge to a Mediterranean coastal area (Balearic Islands, Spain) using radium isotopes

AuthorsGarcía-Solsona, Ester; García-Orellana, Jordi; Masqué, Pere; Garcés, Esther ; Radakovitch, O.; Mayer, A.; Estradé, S.; Basterretxea, Gotzon
KeywordsGroundwater discharge
Inorganic nutrients
Karstic springs phytoplankton proliferations
Radium isotopes
Issue DateMar-2010
CitationBiogeochemistry 97(2-3): 211-229 (2010)
AbstractShort and long-lived radium isotopes (223Ra, 224Ra, 226Ra, 228Ra) were used to quantify submarine groundwater discharge (SGD) and its associated input of inorganic nitrogen (NO3 −), phosphorus (PO4 3−) and silica (SiO4 4−) into the karstic Alcalfar Cove, a coastal region of Minorca Island (Western Mediterranean Sea). Cove water, seawater and groundwater (wells and karstic springs) samples were collected in May 2005 and February 2006 for radium isotopes and in November 2007 for dissolved inorganic nutrients. Salinity profiles in cove waters suggested that SGD is derived from shallow brackish springs that formed a buoyant surface fresh layer of only 0.3 m depth. A binary mixing model that considers the distribution of radium activities was used to determine the cove water composition. Results showed that cove waters contained 20% brackish groundwater; of which 6% was recirculated seawater and 14% corresponded to freshwater discharge. Using a radium-derived residence time of 2.4 days, a total SGD flux of 150,000 m3 year−1 was calculated, consisting of 45,000 m3 year−1 recirculated seawater and 105,000 m3 year−1 fresh groundwater. Fresh SGD fluxes of NO3 −, SiO4 4− and PO4 3− were estimated to be on the order of 18,000, 1,140 and 4 μmol m−2 day−1, respectively, and presumably sustain the high phytoplankton biomass observed in the cove during summer. The total amount of NO3 − and SiO4 4− supplied by SGD was higher than the measured inventories in the cove, while the reverse was true for PO4 3−. These discrepancies are likely due to non-conservative biogeochemical processes that occur within the subterranean estuary and Alcalfar Cove waters
Description19 pages, 6 figures, 3 tables
Publisher version (URL)http://dx.doi.org/10.1007/s10533-009-9368-y
Appears in Collections:(ICM) Artículos
(IMEDEA) Artículos
Files in This Item:
There are no files associated with this item.
Show full item record
Review this work

Related articles:

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.