Challenges and opportunities for sustaining coastal wetlands and oyster reefs in the southeastern United States

Tricia Kyzar; Ilgar Safak; Just Cebrian; Mark W Clark; Nicole Dix; Kaitlyn Dietz; Rachel K Gittman; John Jaeger; Kara R Radabaugh; Annie Roddenberry; Carter S Smith; Eric L Sparks; Benjamin Stone; Gary Sundin; Michelle Taubler; Christine Angelini

doi:10.1016/j.jenvman.2021.113178

Challenges and opportunities for sustaining coastal wetlands and oyster reefs in the southeastern United States

J Environ Manage. 2021 Oct 15:296:113178. doi: 10.1016/j.jenvman.2021.113178. Epub 2021 Jul 2.

Authors

Tricia Kyzar¹, Ilgar Safak², Just Cebrian³, Mark W Clark⁴, Nicole Dix⁵, Kaitlyn Dietz⁵, Rachel K Gittman⁶, John Jaeger⁷, Kara R Radabaugh⁸, Annie Roddenberry⁹, Carter S Smith¹⁰, Eric L Sparks¹¹, Benjamin Stone¹², Gary Sundin¹², Michelle Taubler¹³, Christine Angelini¹⁴

Affiliations

¹ Department of Urban and Regional Planning, University of Florida, Gainesville, FL, USA. Electronic address: tkyzar@ufl.edu.
² Department of Civil and Coastal Engineering, Engineering School of Sustainable Infrastructure and Environment, University of Florida, Gainesville, FL, USA; Department of Civil Engineering, Faculty of Engineering and Natural Sciences, Istanbul Bilgi University, Eski Silahtaraga Elektrik Santrali, 34060, Eyupsultan, Istanbul, Turkey.
³ Northern Gulf Institute, Mississippi State University, Stennis Space Center, MS, USA.
⁴ Department of Soil and Water Sciences, University of Florida, Gainesville, FL, USA.
⁵ Guana Tolomato Matanzas National Estuarine Research Reserve, Ponte Vedra, FL, USA.
⁶ Department of Biology and Coastal Studies Institute, Eastern Carolina University, Greenville, NC, USA.
⁷ Department of Geological Sciences, University of Florida, Gainesville, FL, USA.
⁸ Florida Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute, St. Petersburg, FL, USA.
⁹ Florida Fish and Wildlife Conservation Commission, New Smyrna Beach, FL, USA.
¹⁰ Nicholas School of the Environment, Duke University Marine Lab, Beaufort, NC, USA.
¹¹ Coastal Research and Extension Center, Mississippi State University, Biloxi, MS, USA; Mississippi-Alabama Sea Grant Consortium, Ocean Springs, MS, USA.
¹² South Carolina Department of Natural Resources, Marine Resources Division, Charleston, SC, USA.
¹³ Department of Environmental Engineering Sciences, Engineering School of Sustainable Infrastructure and Environment, University of Florida, Gainesville, FL, USA.
¹⁴ Department of Civil and Coastal Engineering, Engineering School of Sustainable Infrastructure and Environment, University of Florida, Gainesville, FL, USA; Department of Environmental Engineering Sciences, Engineering School of Sustainable Infrastructure and Environment, University of Florida, Gainesville, FL, USA.

PMID: 34225043
DOI: 10.1016/j.jenvman.2021.113178

Abstract

Formed at the confluence of marine and fresh waters, estuaries experience both the seaside pressures of rising sea levels and increasing storm severity, and watershed and precipitation changes that are shifting the quality and quantity of freshwater and sediments delivered from upstream sources. Boating, shoreline hardening, harvesting pressure, and other signatures of human activity are also increasing as populations swell in coastal regions. Given this shifting landscape of pressures, the factors most threatening to estuary health and stability are often uncertain. To identify the greatest contemporary threats to coastal wetlands and oyster reefs across the southeastern United States (Mississippi to North Carolina), we summarized recent population growth and land-cover change and surveyed estuarine management and science experts. From 1996 to 2019, human population growth in the region varied from a 17% decrease to a 171% increase (mean = +43%) with only 5 of the 72 SE US counties losing population, and nearly half growing by more than 40%. Individual counties experienced between 999 and 19,253 km² of new development (mean: 5725 km²), with 1-5% (mean: 2.6%) of undeveloped lands undergoing development over this period across the region. Correspondingly, our survey of 169 coastal experts highlighted development, shoreline hardening, and upstream modifications to freshwater flow as the most important local threats facing coastal wetlands. Similarly, experts identified development, upstream modifications to freshwater flow, and overharvesting as the most important local threats to oyster reefs. With regards to global threats, experts categorized sea level rise as the most pressing to wetlands, and acidification and precipitation changes as the most pressing to oyster reefs. Survey respondents further identified that more research, driven by collaboration among scientists, engineers, industry professionals, and managers, is needed to assess how precipitation changes, shoreline hardening, and sea level rise are affecting coastal ecosystem stability and function. Due to the profound role of humans in shaping estuarine health, this work highlights that engaging property owners, recreators, and municipalities to implement strategies to improve estuarine health will be vital for sustaining coastal systems in the face of global change.

Keywords: Coastal ecosystems; Development; Mangrove; Oyster reef; Population growth; Salt marsh.

MeSH terms

Animals
Ecosystem
Estuaries
Humans
North Carolina
Ostreidae*
Wetlands*