NSF Award
2406523
Alkalinity is a measure of the buffering capacity of water. Compounds such as bicarbonate and carbonate contribute to alkalinity and prevent waters from becoming more acidic. This study focuses on understanding the processes that produce alkalinity in salt marshes. In addition, the project will quantify how much of the alkalinity produced in marshes is transported to the ocean. It is widely known that alkalinity is produced in salt marshes and wetlands. However, it is not yet known how this alkalinity contributes to regional carbon budgets, ocean acidification, and blue carbon. This study will develop a mathematical model that combines estuarine physics, hydrological drivers such as tidal and groundwater flow, and biogeochemistry. The scientists will use this model to estimate how much alkalinity is delivered to the ocean. As part of the project, the lead investigator will participate in outreach activities that promote awareness and understanding across a range of audiences. These activities include: (a) mentoring graduate and undergraduate students, (b) developing blogs and videos and providing reports to stakeholders, and (c) ensuring transparent and open-source data sharing.<br/><br/>This study aims to provide a better understanding of the factors influencing alkalinity fluxes from tidal wetlands and the carbon cycle in the coastal ocean under the effect of climate change. This project will address the following research questions: 1) How do tidal dynamics and saltwater intrusion influence the export of alkalinity during tidal, spring-neap, seasonal, and inter-annual cycles? 2) What are the impacts of sea-level rise (SLR) on the export of alkalinity from tidal marshes and what is the influence of marsh evolution on the carbon cycle in the coastal ocean? To answer these questions, numerical modeling will be primarily utilized, complemented by data analysis and remote sensing techniques. The project will develop and utilize the state-of-the-art SCHISM-ICM-CC-SF-Marsh model along the US East Coast, with Plum Island Estuary serving as a primary study site due to its extensive tidal marsh coverage and rich dataset. Furthermore, future scenarios of SLR and marsh evolution will be simulated to estimate potential changes in alkalinity exports. By integrating interdisciplinary elements, this project will improve understanding of coastal carbon cycling, and advance methodological approaches within this field. Additionally, this project will contribute to the broader exploration of ocean alkalinity enhancement (OAE) as a potential method for carbon dioxide removal (CDR) to mitigate the challenges posed by climate change.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
