title: A GIS typology to locate sites of submarine groundwater discharge.
abstract: Although many researchers agree on the importance of submarine groundwater discharge (SGD), it remains difficult to locate and quantify this process. A groundwater typology was developed based on local digital elevation models and compared to concurrent radon mapping indicative of SGD in the Niantic River, CT USA. Areas of high radon activity were located near areas of high flow accumulation lending evidence to the utility of this approach to locate SGD. The benefits of this approach are three-fold: fresh terrestrial SGD may be quickly located through widely-available digital elevation models at little or no cost to the investigator; fresh SGD may also be quantified through the GIS approach by multiplying pixelated flow accumulation with the expected annual recharge; and, as these data necessarily quantify only fresh SGD, a comparison of these data with SGD as calculated by Rn activity may allow for the separation of the fresh and circulated fractions of SGD. This exercise was completed for the Niantic River where SGD as calculated by the GIS model is 1.2 m(3)/s, SGD as calculated by Rn activity is 0.73-5.5 m(3)/s, and SGD as calculated via a theoretical approach is 1.8-4.3 m(3)/s. Therefore fresh, terrestrial SGD accounts for 22-100% of total SGD in the Niantic River.
authors: Department of Biology, Sacred Heart University, 5151 Park Avenue, Fairfield, CT 06825, USA. Electronic address: rapagliaj@sacredheart.edu.
authors: John
authors: J
authors: Rapaglia
authors: Department of Biology, Sacred Heart University, 5151 Park Avenue, Fairfield, CT 06825, USA. Electronic address: carleymeryl@gmail.com.
authors: Carley
authors: C
authors: Grant
authors: School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY 11794, USA. Electronic address: hbokuniewicz@notes.cc.sunysb.edu.
authors: Henry
authors: H
authors: Bokuniewicz
authors: School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY 11794, USA. Electronic address: tpick@stonybrook.edu.
authors: Tsvi
authors: T
authors: Pick
authors: Institute of Geosciences, Christian Albrechts University of Kiel, Otto-Hahn Platz 1, 24098 Kiel, Germany. Electronic address: jan.scholten@gpi.uni-kiel.de.
authors: Jan
authors: J
authors: Scholten
mesh_terms: D003237:Connecticut; D004784:Environmental Monitoring; D040362:Geographic Information Systems; D060587:Groundwater / Q000032:analysis*; D011834:Radiation Monitoring / Q000379:methods*; D011886:Radon / Q000032:analysis*; D045483:Rivers / Q000737:chemistry*
chemical_list: D011886:Radon
keywords: Digital elevation models; Geographic information systems; Radon mapping; Submarine groundwater discharge