Research interests
My research is aimed at elucidating how abiotic factors and biotic interactions influence aquatic and wetland plant growth and production at the population and community levels in order to understand how those interactions affect ecosystem processes. I am interested in understanding the ways in which wetland plants affect the structure and function of wetland ecosystems and what role they play in wetland population, community, and ecosystem dynamics. While I have conducted research in a variety of aquatic and wetland habitats, I am currently focusing my research in coastal wetlands of the northern Gulf of Mexico and a local freshwater wetland in Alabama.Global Change Effects on Coastal Wetlands
The goal of my coastal wetland research is to understand the linkages and feedbacks that control habitat stability in coastal marshes, specifically how marshes maintain surface elevations relative to sea-level and how external forcing factors (elevated CO2, sea-level rise, fire) affect ecosystem stability. This research requires measurement of surface elevation using Surface Elevation Tables (SETs) and vertical accretion using marker horizons (Fig. 1). It also includes examination of porewater physicochemistry, above- and below-ground production, and organic matter accumulation in marshes so that both physical and biological processes are examined. In this project, my collaborators and I are taking a hierarchical approach in which greenhouse experiments and are combined with field experiments to develop a predictive Structural Equation Model (SEM) that will inform adaptive management strategies. The model can be used by natural resource managers who are attempting to conserve and restore marshes along the Gulf and Atlantic coasts. This research is being conducted in collaboration with scientists at the USGS National Wetlands Research Center and Patuxent Wildlife Research Center as part of the USGS Global Change Program.
Population and Community Dynamics in Temperate Freshwater Wetlands
The goal of my freshwater wetland research is to understand how herbivory, competition, and changes in environmental conditions (flooding) affects wetland plant communities. To date, I have focused this research on the white water lily (Nymphaea odorata) investigating how it responds to invertebrate grazing, competition from another water lily species, and water level fluctuations caused by temporary floating island formation. In addition to this line of research, I am also initiating research in a local emergent wetland that was formerly impounded by beaver activity. Since the draining of the former pond in 1996, hazel alder has been colonizing an area formerly dominated by Juncus effusus and Nymphaea odorata. I am most interested in documenting changes in the wetland community and the role alder plays in nutrient dynamics within the wetland.
Undergraduate or graduate students interested in research opportunities in my lab are encouraged to contact me. Additional information is available on my website.
Figure 1. Measurement of surface elevations and vertical accretion in coastal marshes – (A) access platform for measurement of elevation change, (B) Rod Surface Elevation Table (rSET) used to determine elevation change, (C) close-up of pins lowered to marsh surface, and (D) marker horizons of feldspar applied to marsh surface to measure vertical accretion.