Groundwater flow rates and nitrate removal capacity from an introduced solution were examined for five marsh restoration designs and unvegetated plots shortly after planting and 1 year post-planting. The restoration site was a sandy beach with a wave-dampening fence 10 m offshore. Simulated groundwater flow into the marsh was introduced at a rate to mimic intense rainfall events. Restoration designs varied in initial planting density and corresponded to 25%, 50%, 75% and 100% of the plot area planted. In general, groundwater flow was slower with increasing planting density and decreased from year 0 to year 1 across all treatments. Nevertheless, removal of nitrate from the introduced solution was similar and low for all restoration designs (3–7%) and similar to the unvegetated plots. We suggest that the low NO3− removal was due to sandy sediments allowing rapid flow of groundwater through the marsh rhizosphere, thereby decreasing the contact time of the NO3− with the marsh biota. Our findings demonstrate that knowledge of the groundwater flow regime for restoration projects is essential when nutrient filtration is a target goal of the project.
Dauphin Island Sea Lab, Dauphin Island, Alabama, United States of America;Marine Sciences, University of South Alabama, Mobile, Alabama, United States of America;Dauphin Island Sea Lab, Dauphin Island, Alabama, United States of America;Marine Sciences, University of South Alabama, Mobile, Alabama, United States of America;Dauphin Island Sea Lab, Dauphin Island, Alabama, United States of America
Recommended Citation:
Eric L. Sparks,Just Cebrian,Sara M. Smith. Removal of Fast Flowing Nitrogen from Marshes Restored in Sandy Soils[J]. PLOS ONE,2014-01-01,9(10)