Temporal variability in chemical cycling of the subterranean estuary and associated chemical loading to the coastal ocean
Thesis: Ph. D., Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2014.
| Main Author: | |
|---|---|
| Other Authors: | |
| Format: | Thesis |
| Language: | eng |
| Published: |
Massachusetts Institute of Technology
2014
|
| Subjects: | |
| Online Access: | http://hdl.handle.net/1721.1/87514 |
| _version_ | 1811083255240196096 |
|---|---|
| author | Gonneea, Meagan Joan Eagle |
| author2 | Matthew A. Charette. |
| author_facet | Matthew A. Charette. Gonneea, Meagan Joan Eagle |
| author_sort | Gonneea, Meagan Joan Eagle |
| collection | MIT |
| description | Thesis: Ph. D., Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2014. |
| first_indexed | 2024-09-23T12:30:14Z |
| format | Thesis |
| id | mit-1721.1/87514 |
| institution | Massachusetts Institute of Technology |
| language | eng |
| last_indexed | 2024-09-23T12:30:14Z |
| publishDate | 2014 |
| publisher | Massachusetts Institute of Technology |
| record_format | dspace |
| spelling | mit-1721.1/875142022-01-14T18:42:23Z Temporal variability in chemical cycling of the subterranean estuary and associated chemical loading to the coastal ocean Gonneea, Meagan Joan Eagle Matthew A. Charette. Woods Hole Oceanographic Institution. Joint Program in Oceanography/Applied Ocean Science and Engineering Woods Hole Oceanographic Institution Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Joint Program in Oceanography/Applied Ocean Science and Engineering. Earth, Atmospheric, and Planetary Sciences. Woods Hole Oceanographic Institution. Thesis: Ph. D., Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2014. Cataloged from PDF version of thesis. Includes bibliographical references. At the land-ocean interface, terrestrial groundwater interacts with seawater to form a subterranean estuary, which can play host to dynamic biogeochemical cycling of nutrients, trace metals and radionuclides. This chemically altered groundwater enters the ocean through submarine groundwater discharge (SGD), a process that is driven by a number of physical processes acting on aquifers and the coastal ocean. In this thesis, seasonal variability in chemical cycling and associated loading to the coastal ocean was observed in a monthly time series within the Waquoit Bay (MA, USA) subterranean estuary. The position of the aquifer mixing zone moved seaward with an increase in hydraulic gradient, resulting in low salinity conditions and reduced mixing, while a decrease in gradient led to landward movement, high salinity groundwater and enhanced mixing. At this location, seasonal variability in sea level, not groundwater level, was the dominant variable driving the hydraulic gradient and therefore SGD. Fluxes of sediment bound cations to the ocean increased coincidently with sea level rise due to desorption. There was enhanced nitrogen attenuation during winter, potentially due to longer groundwater residence times, with greater nutrient delivery to coastal waters during the spring and summer bloom. Interannual climate fluctuations that control sea level and precipitation may ultimately control the timing and magnitude of chemical and water flux via SGD. In addition to temporal variability, aquifer lithology influences chemical export. This thesis also demonstrates that SGD from karst subterranean estuaries may play a role in local and global element budgets. The potential for the chemical signature of SGD to be recorded in the coral record was tested through a combination of coral culture experiments and field and modeling studies in the Yucatan Peninsula. Coral barium was well correlated with precipitation for a twelve-year record, with coral geochemistry reflecting the passage of a hurricane in 2002. While additional complexities in deciphering coral records remain, this proxy offers the potential to extend SGD records into the past. by Meagan Joan Eagle Gonneea. Ph. D. 2014-05-23T19:40:24Z 2014-05-23T19:40:24Z 2014 2014 Thesis http://hdl.handle.net/1721.1/87514 879674293 eng M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 331 pages application/pdf Massachusetts Institute of Technology |
| spellingShingle | Joint Program in Oceanography/Applied Ocean Science and Engineering. Earth, Atmospheric, and Planetary Sciences. Woods Hole Oceanographic Institution. Gonneea, Meagan Joan Eagle Temporal variability in chemical cycling of the subterranean estuary and associated chemical loading to the coastal ocean |
| title | Temporal variability in chemical cycling of the subterranean estuary and associated chemical loading to the coastal ocean |
| title_full | Temporal variability in chemical cycling of the subterranean estuary and associated chemical loading to the coastal ocean |
| title_fullStr | Temporal variability in chemical cycling of the subterranean estuary and associated chemical loading to the coastal ocean |
| title_full_unstemmed | Temporal variability in chemical cycling of the subterranean estuary and associated chemical loading to the coastal ocean |
| title_short | Temporal variability in chemical cycling of the subterranean estuary and associated chemical loading to the coastal ocean |
| title_sort | temporal variability in chemical cycling of the subterranean estuary and associated chemical loading to the coastal ocean |
| topic | Joint Program in Oceanography/Applied Ocean Science and Engineering. Earth, Atmospheric, and Planetary Sciences. Woods Hole Oceanographic Institution. |
| url | http://hdl.handle.net/1721.1/87514 |
| work_keys_str_mv | AT gonneeameaganjoaneagle temporalvariabilityinchemicalcyclingofthesubterraneanestuaryandassociatedchemicalloadingtothecoastalocean |