We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
An assessment of iron and calcium amendments for managing phosphorus release from impacted Everglades soils.
- Authors
Dierberg, Forrest; DeBusk, Thomas; Jackson, Scott; Kharbanda, Michelle; Galloway, Stacey; Owens, Patrick; Ivanoff, Delia
- Abstract
The recent implementation of agricultural best management practices (BMPs) and treatment wetlands called stormwater treatment areas (STAs) have reduced phosphorus (P) concentrations and loadings to the Everglades Protection Area (EPA) in Florida (USA). There is a concern that despite reductions in external P loadings, internal loading from the legacy P enrichment of the EPA wetland soils will continue to elevate water column P concentrations, and may impede restoration outcomes. In an effort to explore ways to reduce soil P efflux, we retrieved intact, vegetated (cattail, Typha domingensis) soil monoliths from two P-enriched areas of the EPA and deployed them at a location where they received pre-treated (low P) surface water as ex situ flow-through mesocosms for 21 months with a mid-study 7-week dry down to mimic natural hydroperiod conditions. Two treatments were tested for soils from both sites, using triplicate mesocosms for each treatment. After applying a herbicide (glyphosate) to eliminate the cattail vegetation, iron (Fe as liquid FeCl) amendments provided no P retention benefits in the organic soils from the two sites, and did not yield significantly (P > 0.05; n = 43) lower flux rates (6.1 and 3.5 mg Pm d) than the herbicide/no soil amendment control (3.9 and 2.1 mg Pm d), as was expected. A combination of low oxidation-reduction potential, heightened organic matter P mineralization, high pH, and sulfide production acted interactively to enhance Fe and P mobilization in the Fe-amended mesocosms. The herbicide/limerock (CaCO)-amended soils exhibited significantly lower (P ≤ 0.05; n = 43) P flux (1.3 and 1.1 mg Pm d) than the herbicide/no soil amendment control soils, but it remains unknown whether the observed reduction in P efflux (ranging from 48 to 67%) would justify the expense and potential environmental impacts of applying a surficial limerock amendment to large regions of the P-enriched wetlands.
- Subjects
EVERGLADES (Fla.); IRON; CALCIUM; PHOSPHORUS; WATER purification
- Publication
Wetlands Ecology & Management, 2017, Vol 25, Issue 6, p649
- ISSN
0923-4861
- Publication type
Article
- DOI
10.1007/s11273-017-9542-2