Freshwater Ecosystems; Restoration Ecology
The broad objective of Dr. Palmer's research is to understand what controls stream and wetland ecosystem structure and function. She focuses extensively on restoration ecology as well as how land use, hydrology, and geomorphology influence ecosystem dynamics.
If you are interested in the U.S. National River Restoration database created in 2004, see 7) below
Current research in the Palmer Lab is concentrated on:
1) Evaluating wetland and stream ecosystem functions in Coastal Plain lowlands of Maryland;
2) Understanding how hydrologic restoration of depressional wetlands influences their linkage and material fluxes to stream networks; and
3) Understanding the relationship between wetland inundation and carbon fluxes.
If you're interested in graduate school, see 3) below!
Current Research in Palmer Lab:
1) Coastal Plain wetlands and stream networks. Historically, the mid-Atlantic had vast expanses of low-lying forests with extensive freshwater wetlands and streams. Much of this land has been converted to farming over the last several hundred years. Ongoing pressures include continued farming and the growth of suburban developments. In recognition of the need for new approaches to systematically monitor and assess hydrologic conditions, wetland/stream ecosystem functions, and their impact on water quality, Palmer and colleagues have work on-going in the Eastern Shore of Maryland. This includes using remotely sensed data, particularly radar and lidar, and extensive field sampling and experimentation, to quantify a variety of ecological functions in depressional wetlands that connect to stream networks under certain hydrologic conditions.
2) Natural, Restored, Agricultural Wetlands; Intermittent channels. Worldwide, there are many efforts to restore wetlands lost due to agriculture or other forms of land use change. In the U.S. some of these fall into a category called “Geographically Isolated Wetlands (GIWs).” Our work has been focusing on GIWs on the Delmarva peninsula of the east coast U.S. where we are quantifying the patterns of connectivity of restored, natural, and agricultural wetlands to perennial stream networks. Among other differences, these three classes of wetlands vary in the duration and patterns of their connectivity as well as the amount and composition of dissolved organic matter flowing from them.
3) Wetlands, Stream Networks, and Carbon. . Wetlands are among the most threatened ecosystems on earth yet they play extremely valuable roles in global elemental cycling. As transition points in the landscape between the terrestrial and aquatic realms, they are well known as sources of C production and biomass accumulation, as well as sinks of C received from the surrounding terrestrial environments. Despite their potential importance to understanding carbon fluxes they have not been adequately integrated into global scale terrestrial carbon budgets or into inland water carbon budgets. The Palmer lab has teamed with colleagues Michael Gonsior (organic chemist – aquatic systems and DOC; UMCES), Laura Lapham (biogeochemist - methane cycling; UMCES), Greg McCarty (Hydrology & remote sensing; USDA), Kate Tully (soil biogeochemist, UM) and members of Daniel McLaughlin’s lab (hydrology, VT) to understand how wetland inundation and hydrologic connectivity influences carbon fluxes and stores. The Coastal Plain field sites are on the Eastern Shore of Maryland where members of Palmer’s lab have worked for a number of years. Restored and natural wetlands in this predominantly agricultural region appear to be isolated during much of the year but work by past graduate students Owen McDonough, Jake Hosen, and Steve Epting have documented periods of extensive connectivity between wetlands and perennial streams via intermittent channels. Current work is expanding this to quantify the dynamic nature of wetland area above and below ground and how this influences the fluxes and lability of dissolved and gaseous organic carbon.
Recent and past research has included:
1) quantifying the effects of stream restoration on nitrogen removal in Chesapeake Bay tributaries (with collaborator Solange Filoso);
2) evaluating hydrologic and stream community responses to novel forms of stream restoration called regenerative stormwater conveyance systems (with graduate student Rosemary Fanelli and others);
3) the geomorphic effects of sugar cane agriculture on Brazilian streams (with graduate student Maira Bezerra);
4) climate change impacts on rivers and streams; Empirical work and modeling on the interactive effects of land use change and climate change on stream ecosystem services (with multiple collaborators);
5) ecosystem services and stream ecosystems (with Postdocs Catherine Febria and Ben Koch);
6) effects of land use change on stream ecosystems (multiple students and postdocs);
7) synthesizing the scientific status of riverine restoration nationally (NRRSS project; with many collaborators by especially Emily Bernhardt).
More about NRRSS: Through an NSF-NCEAS award and funding from the Packard and C.S. Mott Foundations, Dr. Palmer along with collaborators, Dr. J. D. Allan (University of Michigan) and former postdoc Dr. Emily Bernhardt (now at Duke University) organized the National River Restoration Science Synthesis (NRRSS) project. The goal of the NRRSS project was to provide a national level scientific synthesis that can be used to inform policy at local, regional, and national levels. The methods involved in-depth research at eight geographic regions in the United States. The U.S.G.S. was a partner in developing the database structure and they have helped us make the database publicly available (https://github.com/khondula/nrrss). Results from the national synthesis were published in Science in 2005 and results for the Chesapeake Bay region in Frontiers in Ecology & the Environment in 2005. The second phase of this work involved interviewing a large number of practitioners to gather more detailed information on how projects were implemented, monitored, and their degree of success. The results from this work will appear in a special issue of the journal Restoration Ecology sometime in 2007. The NRRSS team has published an article proposing five criteria for evaluating the ecological success of a river restoration project. Their paper on proposed criteria is the lead article in a special issue of the British Ecological Society's Journal of Applied Ecology have received positive comments from an international group of rivers scientists (Jansson et al. 2005) and from a group of restoration practitioners (Gillilan et al. 2005). All of these articles are in the February issue (volume 42 (1)) of the journal. Finally, Palmer and co-author Dave Allan have just published a paper with recommendations for federal policy changes to enhance the effectiveness of river restoration (Issues in Science and Technology 2006).