Photo Credit: Baxter Miller
Photo Credit: Baxter Miller
Land-use change, runoff pollution and a vibrant shellfish industry render North Carolina among the most socioeconomically vulnerable states to future acidification impacts. An understanding of these factors can lead to the development of the tools necessary for coastal industries and ecosystems to mitigate and adapt to these changes.
Research and Partnerships Around North Carolina
Impacts to Organisms
SHELL GROWTH: There are only a few examples of research on Eastern Oysters stocks from the U.S. Southeast. Studies in other regions have found significant vulnerabilities in larval and juvenile shell mineralogy as well as some effects on metabolic rates
REPRODUCTION: Though oyster reproduction appeared to be resilient to open ocean projections of pH change, “severe” treatments (pH 7.1) showed significant effects on reproduction with female reproduction particularly vulnerable. These conditions may sound extreme, but they are not uncommon in coastal marsh habitats in the summer. If the results of these experiments are reflected in oysters' natural habitats, there could be seasonal bottlenecks in oyster populations- males can reproduce but if females can't, we'll have fewer oysters.
PLANKTON: Plankton are the small organisms that drift in seawater and include a rich diversity of bacteria, fungi, phytoplankton (small plants) and zooplankton. Many studies show that acidification can shift community structure of plankton; plankton are at the base of the food web, so this could have implications for many other organisms.
FISH: Species, such as the red drum, which are important in NC waters, appear to be resilient but there may be effects of acidification on early life stages of some species (e.g. summer flounder). It is almost important to consider the indirect consequences of acidification on fish habitat and the organisms, such as plankton, that fish eat.
CORAL: Deep-sea corals offshore of the NC coast serve as important habitat and nursery grounds for a diversity of fishes. Like their shallow-water counterparts, deep-sea coral are likely to experience reduced calcification and changes to their ability to form reef-framework. Learn more about North Carolina's deep reefs here.
PICO: The Pivers Island Coastal Observatory, or PICO, is operated by the Dr. Zackary Johnson laboratory at Duke University. This monitoring site began in 2010 and includes both a coastal station at Pivers Island as well as offshore sampling. Learn more.
MODMON: The Neuse River Estuary Modeling and Monitoring Project (MODMON) is a collaborative effort between the University of North Carolina and the North Carolina Department of Environmental and Natural Resources (NC-DENR). The effort extensively monitors and assesses coastal water, including pH.
ECOA: The East Coast Ocean Acidification (ECOA) research cruise passes by once every 3 to 4 years with multiple transects off the North Carolina coast. The research cruise is supported by the National Oceanic and Atmospheric Ocean Acidification Program. Learn more about their monitoring efforts here.
THE INDUSTRY: The oyster industry currently generated $7.5 million in economic activity but has the potential to expand to over $100 million by 2030. North Carolina's Strategic Plan for Shellfish Mariculture cites maintaining and improving water quality as a key recommendation, noting that in 2017, 19% of growing areas were closed due to poor water quality and 14% closed because of lack of funding to monitor water quality.
SENSITIVITY: Research has shown North Carolina is within the top 20% of most economically sensitive states for acidification impacts on shellfisheries. This high sensitivity was driven by the landed value of shellfish, the proportion of shellfish to all fish harvested and the number of jobs in the industry. Explore the map here.
ADAPTATION CAPACITY: North Carolina, and most of U.S. Southeast, is considered to have low adaptive capacity to the effects of acidification on shellfisheries. This conclusion was based off metrics that included the amount of funding to Sea Grants, status of climate adaptation plans, and existence of state policy on acidification. Explore the map here.
Impacts from Hurricanes
North Carolina is no stranger to storms and these passing events can really mix things up in our coastal waters. Huge amounts of fresh water from rain can make it harder for seawater to buffer against changes in pH, meaning that we can see big drops in pH during and after big storms. Furthermore, storms can bring organic debris, like marsh grass, into the water where it's broken down by bacteria that release CO2 (just like we breathe out CO2). Much of this CO2 will actually go back into the atmosphere! Scientists are working to understand storms' role in this exchange.