Show simple item record

dc.contributor.authorPovinec, Pavel P.  Concept link
dc.contributor.authorBurnett, William C.  Concept link
dc.contributor.authorBeck, A.  Concept link
dc.contributor.authorBokuniewicz, Henry J.  Concept link
dc.contributor.authorCharette, Matthew A.  Concept link
dc.contributor.authorGonneea, Meagan E.  Concept link
dc.contributor.authorGroening, M.  Concept link
dc.contributor.authorIshitobi, T.  Concept link
dc.contributor.authorKontar, E.  Concept link
dc.contributor.authorKwong, L. Liong Wee  Concept link
dc.contributor.authorMarie, D. E. P.  Concept link
dc.contributor.authorMoore, Willard S.  Concept link
dc.contributor.authorOberdorfer, J. A.  Concept link
dc.contributor.authorPeterson, R.  Concept link
dc.contributor.authorRamessur, R.  Concept link
dc.contributor.authorRapaglia, J.  Concept link
dc.contributor.authorStieglitz, T.  Concept link
dc.contributor.authorTop, Zafer  Concept link
dc.date.accessioned2011-12-12T20:45:56Z
dc.date.available2011-12-12T20:45:56Z
dc.date.issued2011-09
dc.identifier.urihttps://hdl.handle.net/1912/4926
dc.descriptionAuthor Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Journal of Environmental Radioactivity 104 (2012): 24-45, doi:10.1016/j.jenvrad.2011.09.009.en_US
dc.description.abstractSubmarine groundwater discharge (SGD) into a shallow lagoon on the west coast of Mauritius Island (Flic-en-Flac) was investigated using radioactive (3H, 222Rn, 223Ra, 224Ra, 226Ra, 228Ra) and stable (2H, 18O) isotopes and nutrients. SGD intercomparison exercises were carried out to validate the various approaches used to measure SGD including radium and radon measurements, seepage-rate measurements using manual and automated meters, sediment bulk conductivity and salinity surveys. SGD measurements using benthic chambers placed on the floor of the Flic-en-Flac Lagoon showed discharge rates up to 500 cm/day. Large variability in SGD was observed over distances of a few meters, which were attributed to different geomorphological features. Deployments of automated seepage meters captured the spatial and temporal variability of SGD with a mean seepage rate of 10 cm/day. The stable isotopic composition of submarine waters was characterized by significant variability and heavy isotope enrichment and was used to predict the contribution of fresh terrestrially derived groundwater to SGD (range from a few % to almost 100 %). The integrated SGD flux, estimated from seepage meters placed parallel to the shoreline, was 35 m3/m day, which was in a reasonable agreement with results obtained from hydrologic water balance calculation (26 m3/m day). SGD calculated from the radon inventory method using in situ radon measurements were between 5 and 56 m3/m per day. Low concentrations of radium isotopes observed in the lagoon water reflected the low abundance of U and Th in the basalt that makes up the island. High SGD rates contribute to high nutrients loading to the lagoon, potentially leading to eutrophication. Each of the applied methods yielded unique information about the character and magnitude of SGD. The results of the intercomparison studies have resulted a better understanding of groundwater-seawater interactions in coastal regions. Such information is an important pre-requisite for the protection management of coastal freshwater resources.en_US
dc.description.sponsorshipThe financial support provided by the IOC and IHP of UNESCO for travel arrangements, and by the IAEA’s Marine Environment Laboratories for logistics is highly acknowledged. MAC and MEG were supported in part by the US National Science Foundation (OCE-0425061 and OCE-0751525). PPP acknowledges a support provided by the EU Research & Development Operational Program funded by the ERDF (project No. 26240220004), and the Slovak Scientific Agency VEGA (grant No. 1/108/08). The International Atomic Energy Agency is grateful to the Government of the Principality of Monaco for support provided to its Marine Environment Laboratories.en_US
dc.format.mimetypeapplication/pdf
dc.language.isoen_USen_US
dc.relation.urihttps://doi.org/10.1016/j.jenvrad.2011.09.009
dc.subjectSubmarine groundwater dischargeen_US
dc.subjectGroundwateren_US
dc.subjectSeawateren_US
dc.subjectSeepage metersen_US
dc.subjectStable isotopesen_US
dc.subjectδDen_US
dc.subjectδ18Oen_US
dc.subjectTritiumen_US
dc.subjectRadium isotopesen_US
dc.subjectRadonen_US
dc.subjectNutrientsen_US
dc.subjectCoastal zoneen_US
dc.subjectVolcanic islanden_US
dc.subjectMauritius Islanden_US
dc.titleIsotopic, geophysical and biogeochemical investigation of submarine groundwater discharge : IAEA-UNESCO intercomparison exercise at Mauritius Islanden_US
dc.typePreprinten_US


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record