National Science Foundation
08/2013 – 07/2017
Martin, Jonathan Bowman
Ogram, Andrew V
Goals and Objectives
This project seeks to address integrative questions related to the impacts of rising sea level and changing coastal demographics on water quality and quantity in coastal aquifers. Sea level is projected to rise by 1 m or more by 2100. Although rising sea level will increase storm-driven inundation of coastal zones, another subtle, but potentially more critical impact will be changes to water resources provided by coastal aquifers. These impacts will be exacerbated by burgeoning coastal populations and associated land use changes and increased groundwater withdrawals. Impacts will include salinization of potable water resources and alterations to coastal ecosystems that rely on discharge of fresh water. Flow through coastal aquifers varies between end-member systems including diffusely discharging water, mostly from granular siliciclastic sediments, to point discharge from springs in carbonate platforms. In addition to changes in salinity as sea level rises, microbial communities within the aquifers, and their functions, may be altered as a result of changing salinity, and associated changes in redox conditions should alter the quality of the ground water, particularly in its nitrogen and redox-sensitive metal compositions.
The project seeks to answer 5 questions: (1) how will changing coastal demographics and sea level rise impact the sustainability of coastal water resources, (2) what are the relative magnitudes of salinization in coastal aquifers from diffuse to point discharge, (3) how does salinization affect resilience of aquifer microbial communities, (4) will these changes in microbial communities affect the quality of water in coastal aquifers and hence the cost of water supplies, and (5) what strategies can be proposed to improve the sustainability of these water resources?
Field sites include 2 locations. The Puerto Morelos Lagoon on the east coast of the Yucatan peninsula, which is characterized by numerous spring discharges. Indian River Lagoon on the east coast of Florida, which is characterized by diffuse flow from siliciclastic sediments.