RAPID: Collaborative Research: Carbon and nutrient responses in an estuarine-coastal complex impacted by floodwaters from Hurricane Matthew

This project constitutes a rapid-response effort to investigate the effects of the extreme flooding event of Hurricane Matthew on coastal cycling of carbon and nutrient elements. The investigators aim to improve our understanding of how estuaries and coastal systems respond to extreme events by measuring carbon, nitrogen, and phosphorus loading into the Neuse River Estuary-Pamlico Sound (NRE-PS) coastal ecosystem. The NRE-PS is the urgent study site to examine resulting effects of Hurricane Matthew on coastal environments because it is downstream of the most intense flooding that occurred, and it is located on the North Atlantic 'hurricane track', likely to be impacted by future extreme events. Furthermore, it is the focus of a long-term monitoring program in that system, the Neuse River Estuary Modeling and Monitoring Program (ModMon), which was initiated in 1993. That date is significant because it preceded a recent rise in Atlantic tropical cyclone activity and has been able to capture the biogeochemical and ecological effects of major storms that have impacted the NC coast, including Hurricanes Fran (1996), Floyd (1999), Isabel (2003), and Irene (2011). Incorporating intensive sampling of the Hurricane Matthew flooding in the context of these ongoing observations will enable a comparison of the material fluxes into this coastal environment resulting from a major tropical storm and provide a comparison with other coastal environments. Outcomes of this work will be communicated widely via existing outreach efforts of each investigator's research programs to local and regional resource managers, regulators, and other stakeholders. Nutrient loading will be critical information for stakeholders because the Neuse Estuary is an EPA 303(d) listed waterway impaired for nitrogen. Project results can aid in understanding the effects of extreme weather events on ecosystem disturbances and inform coastal carbon flux estimates.

Specific questions to be addressed in the context of this project include: 1) How do coastal carbon and nitrogen budgets respond to floodwaters from tropical storms and hurricanes? 2) What is the biological and photochemical reactivity of this material? The first question can be answered via a relatively short, yet intense, period of observations, such as is proposed here. The second question, which has potential teleconnections to climate in terms of carbon fluxes, food web responses, and other ecosystems processes, requires a longer duration study. However, Question 2 could be answered by further study of samples collected during a short and intense period of sampling proposed to answer Question 1. Work proposed in this project will result in estimates of fluxes and reservoirs of key constituents such as dissolved inorganic carbon (DIC), dissolved and particulate organic carbon and nitrogen (DOC, POC, DON, PON), and N and P nutrients, as well as chlorophyll biomass and pigment analyses.