| dc.identifier.uri | http://hdl.handle.net/11401/77394 | |
| dc.description.sponsorship | This work is sponsored by the Stony Brook University Graduate School in compliance with the requirements for completion of degree. | en_US |
| dc.format | Monograph | |
| dc.format.medium | Electronic Resource | en_US |
| dc.language.iso | en_US | |
| dc.publisher | The Graduate School, Stony Brook University: Stony Brook, NY. | |
| dc.type | Dissertation | |
| dcterms.abstract | Understanding how changes in ecological communities affect ecosystem function, including the provisioning of ecosystem services, is a critical challenge in the field of ecology. I apply a trait-based approach to link the characteristics of plant communities to their effects on denitrification and nitrogen-removal ecosystem services. My work has addressed this challenge at multiple scales using literature syntheses, field surveys, field manipulations, and greenhouse experiments. In a meta-analysis of 419 published measurements of denitrification, I estimated that vegetation on average increases the ability of marshes to remove nitrogen by 55% and that this effect differs among species. My study was the first to quantify the general effect of wetland vegetation on this globally important term of the nitrogen cycle. I pursued two field projects to explain variation among species by investigating interactions among plant traits and sediment properties and processes. In the first, I determined that removing an invasive marsh grass, <i>Phragmites australis</i>, increased sediment nitrogen concentrations and decreased denitrification relative to marshes containing invasive <i>Phragmites</i> or native cattail species. These results suggest a trade-off between removing invasive species to conserve biodiversity and managing wetlands to promote nitrogen removal. The second field project addressed interactions between traits of dominant salt marsh grass <i>Spartina alterniflora</i> and ecosystem properties and processes along a land-use gradient on Long Island, NY. Root growth of <i>S. alterniflora</i> responded positively to salinity and negatively to nitrogen availability, suggesting that eutrophication and sea-level rise may have opposing effects on root mass, and therefore marsh stability, in the future. Results from greenhouse experiments, which employed a novel combination of oxygen-sensitive planar optodes and microbial process measurements, suggested that <i>S. alterniflora</i> roots influence nitrification and denitrification rates by introducing oxygen to sediments. Field measurements from Long Island marshes confirmed that plant traits are useful predictors of denitrification potential among wetland sites, offering superior estimates relative to those obtained from abiotic predictors. Results also suggest that the influence of plant communities on denitrification scales positively with aboveground biomass. Together my results support the utility of trait-based approaches in understanding the role of plant communities in promoting nitrogen-removal services in wetland ecosystems. | |
| dcterms.available | 2017-09-20T16:52:37Z | |
| dcterms.contributor | Padilla, Dianna | en_US |
| dcterms.contributor | Baines, Stephen B. | en_US |
| dcterms.contributor | Gurevitch, Jessica | en_US |
| dcterms.contributor | Rogers, Alistair | en_US |
| dcterms.contributor | Findlay, Stuart. | en_US |
| dcterms.creator | Alldred, Mary Katherine | |
| dcterms.dateAccepted | 2017-09-20T16:52:37Z | |
| dcterms.dateSubmitted | 2017-09-20T16:52:37Z | |
| dcterms.description | Department of Ecology and Evolution. | en_US |
| dcterms.extent | 241 pg. | en_US |
| dcterms.format | Application/PDF | en_US |
| dcterms.format | Monograph | |
| dcterms.identifier | http://hdl.handle.net/11401/77394 | |
| dcterms.issued | 2015-12-01 | |
| dcterms.language | en_US | |
| dcterms.provenance | Made available in DSpace on 2017-09-20T16:52:37Z (GMT). No. of bitstreams: 1
Alldred_grad.sunysb_0771E_12449.pdf: 5250350 bytes, checksum: baab7b960408cc5c90e98cd0c0a6eaa2 (MD5)
Previous issue date: 1 | en |
| dcterms.publisher | The Graduate School, Stony Brook University: Stony Brook, NY. | |
| dcterms.subject | Ecology | |
| dcterms.subject | community structure, ecosystem services, functional traits, global change, nitrogen cycling | |
| dcterms.title | Using Plant Traits to Predict Denitrification in Wetland Ecosystems | |
| dcterms.type | Dissertation | |
