Best Management Practices for Post-construction Restoration of Rights-of-way in Saltwater Marshes, Estuaries, and Other Tidally Influenced Areas

Saltwater marshes or salt marshes are capable of providing to fauna and flora a biologically desirable environment while operating as a sink for sequestering large amounts of heavy metals. Salt marshes have the highest value of net primary productivity among terrestrial and wetland ecosystems and are adversely impacted and threatened by land-use change. Preservation and restoration practices for salt marshes require well-established databases characterizing these coastal areas based on vegetation, soil, and water. This study uses field-based experiments to characterize the native halophytic species and pore-water properties found along the Georgia coast. In addition, laboratory-based experiments were carried out to identify texture, bulk density, carbon to nitrogen (C/N) ratio, trace elements, and the mineralogy of the hydric soils of eight salt marshes located along Georgia’s shoreline. A greenhouse experiment was conducted to evaluate the growth of four predominant salt marsh vegetation types (Spartina alterniflora, Juncus roemerianus, Schoenoplectus tabernaemontani, and Borrichia frutescens) in eight engineered soil mixtures that approximate the physical and chemical properties of salt marsh soils, along with two controls providing baselines for growth in potting soil, as well as growth in the material specified in the current GDOT construction specifications for restoration of disturbed salt marshes. The results demonstrate that growth rates of halophytes depend on salinity of pore-water and soil constituents and properties such as texture, bulk density, organic matter, and mineralogy. Further, resulting statistical analyses reveal a correlation among salt marsh–predominant vegetation types and pore water redox potential. Also, percent organic matter and fine content of salt marsh soils are statistically significant drivers of soil bulk density.

• Record URL:
  http://g92018.eos-intl.net/eLibSQL14_G92018_Documents/RP%2017-11%20Final_6.17.2020%20-%20clean%20copy.pdf
• 
• Record URL:
  https://rosap.ntl.bts.gov/view/dot/53930
• Corporate Authors:

  University of Georgia, Athens

  College of Engineering
  Driftmier Engineering Center
  Athens, Georgia  United States  30602

  Georgia Department of Transportation

  Office of Performance-based Management and Research
  600 West Peachtree St. NW
  Atlanta, GA  United States  30308

  U.S. Department of Transportation

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Christian, Jason
  • Kim, Sonny
  • Durham, Stephan A
  • Sutter, Lori
  • Hikouei, Iman Salehi
  • House, Katelyn
• Publication Date: 2020-6

Language

• English

Media Info

• Media Type: Digital/other
• Edition: Final Report
• Features: Appendices; Figures; Maps; Photos; References; Tables;
• Pagination: 186p

Subject/Index Terms

• TRT Terms: Bulk density; Coastal zone management; Estuaries; Marshes; Restoration ecology; Saline soils; Salinity; Salt water areas
• Geographic Terms: Georgia
• Subject Areas: Environment; Geotechnology; Highways; Hydraulics and Hydrology;

Filing Info

• Accession Number: 01745917
• Record Type: Publication
• Report/Paper Numbers: FHWA-GA-20-1711, 17-11, GEORGIA DOT RESEARCH PROJECT 17-11
• Contract Numbers: PI# 0015709
• Files: NTL, TRIS, ATRI, USDOT, STATEDOT
• Created Date: Jul 22 2020 3:49PM