Grantee Research Project Results
The Effect of Genotypic Variation in Spartina alterniflora on the Ecosystem Services Provided by Coastal MarshesEPA Grant Number: FP917305
Title: The Effect of Genotypic Variation in Spartina alterniflora on the Ecosystem Services Provided by Coastal Marshes
Investigators: Bernik, Brittany Marie
Institution: Tulane University of Louisiana
EPA Project Officer: Cobbs-Green, Gladys M.
Project Period: August 1, 2011 through July 31, 2014
Project Amount: $126,000
RFA: STAR Graduate Fellowships (2011)
Research Category: Academic Fellowships , Fellowship - Ecosystem Services: Terrestrial Systems Soil and Plant Ecology
This project seeks to examine variation in ecosystem services arising due to the genetic identity of foundational marsh plants used for restoration—particularly between cultivated and wildtype clones. To this end, the study will meet the following objectives: (1) quantify phenotypic variation across genotypes; (2) quantify differences in marsh accretion across genotypes; and (3) quantify differences in agricultural pollutant amelioration across genotypes.Approach:
Greenhouse experiments will be used to assess variation in plant functional traits between genotypes. Traits expected to influence the provisioning of ecosystem services will be measured, including above and belowground biomass, root and rhizome distribution, canopy height and stem density. Transplantation field experiments will compare sediment and vegetative accretion across cultivated and wildtype clones using radiometric dating and by quantifying soil organics. Separate greenhouse trials will administer nutrient loading treatments, and water nitrate levels will be monitored across genotypes to evaluate differences in excess nutrient removal.Expected Results:
Genotypes will differ significantly from one another, with cultivars showing the strongest differences in plant functional traits, both from each other and from wildtype plants. Genotypes with denser root mats and a higher proportion of belowground biomass will survive and accrete more organics, while genotypes exposing more shoot surface area will have higher accretion of mineral sediments. Nutrient uptake also will differ between genotypes, with some clones showing greater potential for water treatment.
Potential to Further Environmental/ Human Health Protection
Marsh restoration increasingly relies on cultivars developed for ease of propagation. This project will provide information on how using these genotypes affects marsh accretion and nutrient uptake—services that provide flood protection and storm buffering, as well as water treatment that ameliorates the hypoxic “dead zone” in the Gulf of Mexico.Supplemental Keywords:
community genetics, ecosystem engineering, ecosystem services, marsh restoration, Spartina alterniflora