Grantee Research Project Results

2004 Progress Report: Effects of Salinity and Bottom Substrate Composition on the Growth and Proliferation of Widgeongrass (Ruppia maritima)

EPA Grant Number: R829584C003
Subproject: this is subproject number 003 , established and managed by the Center Director under grant R829584
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
Center: Louisiana Environmental Research Center (McNeese State)
Center Director: Ford, Mark A.
Title: Effects of Salinity and Bottom Substrate Composition on the Growth and Proliferation of Widgeongrass (Ruppia maritima)
Investigators: Ford, Mark A. , Stacy, Gus
Institution: McNeese State University
EPA Project Officer: Packard, Benjamin H
Project Period: February 1, 2002 through January 31, 2007
Project Period Covered by this Report: February 1, 2003 through January 31, 2004
RFA: Targeted Research Center (2004) Recipients Lists
Research Category: Hazardous Waste/Remediation , Targeted Research

Objective:

This is one of seven subprojects of the Louisiana Environmental Research Center (LERC). For information on the other subprojects conducted by LERC, see the individual reports for R829548C001 through R829548C007.

The growth and proliferation of widgeongrass is affected by various factors such as sunlight, temperature, and salinity. In the sulfur-rich, organic bottom substrate of Gulf of Mexico tidal marshes, widgeongrass growth and proliferation is hindered severely at salinities of 12-15 ppt. In the sandy soils of the coastal bend of Gulf bays, however, widgeongrass thrives at salinities of 25 ppt. This salinity- and bottom substrate-dependent growth has not been characterized fully. The differences in salt-tolerance likely are dependent on the soil reduction-oxidation potential of the two different types of bottom substrate. The objectives of this project are to determine the effects that salinity and bottom substrate composition contribute to widgeongrass growth. Also, we are attempting to conduct genetic analyses using specific genomic markers to determine if genetic drift has occurred between R. maritima stands that grow in different environments and in different states across the Gulf Coast.

Progress Summary:

This is one of seven subprojects of the Louisiana Environmental Research Center (LERC). For information on the other subprojects conducted by LERC, see the individual reports for R829548C001, R829548C002, and R829548C004 through R829548C007.

Our initial results from the widgeongrass genetic project have revealed that inverted terminal repeat sequences (ITRS) genetic markers will be useful tools for the analysis of this plant species. We are in the process of collecting samples from different locations that reflect different salinities. These samples will be used for sequence comparisons of the ITRS regions.

We successfully have grown stock cultures of widgeongrass in subterranean 110-gallon stock tanks. The cultures are healthy and will be used to seed the subcultures for the project on the effects of the salinity and bottom substrate. The subculture buckets have been prepared using the various bottom substrates and are ready to be seeded with widgeongrass. A platform (8’x16’) for this experiment has been built that features a frame to hold the 17 fluorescent light fixtures (34 40-watt, 48” bulbs). This project is expected to begin early in the summer of 2005.

Future Activities:

The preliminary work for these experiments has been conducted, and the data will be collected during the next 6-8 months. We will collect R. maritima samples from different environments along the Gulf Coast and compare the genetic diversity using the ITRS regions mentioned above. In addition, we will begin to collect data to investigate the contribution of salinity and bottom substrate on the growth and proliferation of widgeongrass.

Supplemental Keywords:

wetlands, wetland restoration, wetland remediation, marsh, Louisiana, restored marshes, sedimentation rate, vertical soil accretion, root zone influences,, Scientific Discipline, Ecosystem Protection/Environmental Exposure & Risk, Water, Restoration, Ecological Risk Assessment, Aquatic Ecosystem Restoration, Ecology and Ecosystems, water quality, restoration strategies, wetland plant restoration, remediation, coastal environments, wetland restoration, land use, salt water intrusion, ecological recovery

Relevant Websites:

http://www.mcneese.edu/lerc Exit

Progress and Final Reports:

Original Abstract

2002

2003

2005

Final

Main Center Abstract and Reports:

R829584    Louisiana Environmental Research Center (McNeese State)

Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
R829584C001 Wetland Restoration and Remediation in Southwest Louisiana Marshes: A Study of Soil Elevation, Vertical Accretion, Shallow Subsidence and Root Zone Influences in Marshes Restored Using a Variety of Techniques
R829584C002 Developing Methods for Identifying Suitable Donors for Wetland Plant Restoration Through Transplantation
R829584C003 Effects of Salinity and Bottom Substrate Composition on the Growth and Proliferation of Widgeongrass (Ruppia maritima)
R829584C004 A Comparison of Health Parameters and Parasites in the Marsh Rice Rat Oryzomys palustris From Natural Freshwater, Saltwater, and Restored Marshes in the Sabine National Wildlife Refuge
R829584C005 Comparison of Metal Concentrations in Soils, Sediments, and Selected Species From the Area Around Chevron Texaco No. 2 Bayou Tank Battery in the Sabine National Wildlife Refuge in Southwest Louisiana and Preliminary Determination of Oxidation State
R829584C006 Use of The Prairie Garden and Plant Material Center To Collect, Propagate, and Maintain Breeder Blocks and Garden Specimens of Louisiana Prairie And Wetland Ecotypes
R829584C007 Density of Marsh Periwinkles and Fire Ant Mounds in Natural and Restored Marshes in the Sabine National Wildlife Refuge