Karen McKee is a Scientist Emeritus at the USGS Wetland and Aquatic Research Center.
Karen L. McKee is a Scientist Emeritus (retired) with the U.S. Geological Survey. She received both a master’s degree and doctorate in botany and conducted research in the field of wetland plant ecology for forty years. Research topics have included adaptations of plants to stressful environments and effects of elevated CO2, climate change, sea-level rise, and hurricanes on wetlands. Her scientific work has been published in over 100 peer-reviewed journal articles and books; she has also produced several peer-reviewed videos. McKee has been active in promoting science communication by scientists and has worked to encourage more scientists and science students to acquire better multimedia skills.
Science and Products
Soil elevation change in mangrove forests and marshes of the Greater Everglades: a regional synthesis of surface elevation table-marker horizon (SET-MH) data
Above- and belowground biomass production, decomposition, and wetland elevation change in transitional coastal wetland communities exposed to elevated CO2 and sediment deposition: a mesocosm study from 2012 to 2014
Hurricane sedimentation in a subtropical salt marsh-mangrove community in the Mississippi River Delta Complex unaffected by vegetation type
Will fluctuations in salt marsh - mangrove dominance alter vulnerability of a subtropical wetland to sea-level rise?
Assessing coastal wetland vulnerability to sea-level rise along the northern Gulf of Mexico coast: gaps and opportunities for developing a coordinated regional sampling network

Rapidly changing range limits in a warming world: Critical data limitations and knowledge gaps for advancing understanding of mangrove range dynamics in the southeastern USA
Soil elevation change in mangrove forests and marshes of the greater Everglades: A regional synthesis of surface elevation table-marker horizon (SET-MH) data
Presence of the herbaceous marsh species Schoenoplectus americanus enhances surface elevation gain in transitional coastal wetland communities exposed to elevated CO2 and sediment deposition events
The history of surface-elevation paradigms in mangrove biogeomorphology
Does geomorphology determine vulnerability of mangrove coasts to sea-level rise?
How plants influence resilience of salt marsh and mangrove wetlands to sea-level rise
The field trip that changed the course of my career
Hurricane sedimentation in a subtropical salt marsh-mangrove community is unaffected by vegetation type
The shifting saltmarsh-mangrove ecotone in Australasia and the Americas
Will fluctuations in salt marsh–mangrove dominance alter vulnerability of a subtropical wetland to sea‐level rise?
Assessing coastal wetland vulnerability to sea-level rise along the northern Gulf of Mexico coast: Gaps and opportunities for developing a coordinated regional sampling network
Species and tissue type regulate long-term decomposition of brackish marsh plants grown under elevated CO2 conditions
Science and Products
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Soil elevation change in mangrove forests and marshes of the Greater Everglades: a regional synthesis of surface elevation table-marker horizon (SET-MH) data
The surface elevation table (SET)-marker horizon (MH) approach (SET-MH, together) is a method for quantifying surface elevation change through measurements of surface and subsurface processes that control wetland soil elevation. This dataset combines SET-MH data from five different U.S. Geological Survey efforts to monitor surface elevation change in the coastal wetlands of the Greater EvergladesAbove- and belowground biomass production, decomposition, and wetland elevation change in transitional coastal wetland communities exposed to elevated CO2 and sediment deposition: a mesocosm study from 2012 to 2014
This data release includes belowground primary productivity, decomposition, and surface elevation change data from a two-year mesocosm experiment from 2012 to 2014. We conducted experimental greenhouse manipulations of atmospheric CO2 (double ambient CO2) and sediment deposition to simulate a land-falling hurricane under future climate conditions. Experimental greenhouse conditions mimicked a landHurricane sedimentation in a subtropical salt marsh-mangrove community in the Mississippi River Delta Complex unaffected by vegetation type
Hurricanes periodically deliver sediment to coastal wetlands, such as those in the Mississippi River Delta Complex (MRDC), slowing elevation loss and improving resilience to sea-level rise. However, the amount of hurricane sediment deposited and retained in a wetland may vary depending on the dominant vegetation. In the subtropical climate of the MRDC, the black mangrove (Avicennia germinans (L.)Will fluctuations in salt marsh - mangrove dominance alter vulnerability of a subtropical wetland to sea-level rise?
To avoid submergence during sea-level rise, coastal wetlands build soil surfaces vertically through accumulation of inorganic sediment and organic matter. At climatic boundaries where mangroves are expanding and replacing salt marsh, wetland capacity to respond to sea-level rise may change. To compare how well mangroves and salt marshes accommodate sea-level rise, we conducted a manipulative fieldAssessing coastal wetland vulnerability to sea-level rise along the northern Gulf of Mexico coast: gaps and opportunities for developing a coordinated regional sampling network
The study area included the coasts of all five U.S. states along the northern Gulf of Mexico (i.e., Florida, Alabama, Mississippi, Louisiana, and Texas). We contacted federal, state, and university-affiliated scientists working with SET-MH data within this area to obtain the geographic coordinates and the installation year for each SET-MH station. Please note that while our inventory is extensive - Multimedia
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What Lies Beneath: Using Mangrove Peat to Study Ancient Coastal Environments and Sea-Level Rise - Publications
Filter Total Items: 70
Rapidly changing range limits in a warming world: Critical data limitations and knowledge gaps for advancing understanding of mangrove range dynamics in the southeastern USA
Climate change is altering species’ range limits and transforming ecosystems. For example, warming temperatures are leading to the range expansion of tropical, cold-sensitive species at the expense of their cold-tolerant counterparts. In some temperate and subtropical coastal wetlands, warming winters are enabling mangrove forest encroachment into salt marsh, which is a major regime shift that hasAuthorsRémi Bardou, Michael Osland, Steven B. Scyphers, Christine C. Shepard, Karen E. Aerni, Jahson B. Alemu, Robert Crimian, Richard Day, Nicholas Enwright, Laura Feher, Sarah L. Gibbs, Kiera O'Donnell, Savannah H. Swinea, Kalaina Thorne, Sarit Truskey, Anna R. Armitage, Ronald J. Baker, Joshua L. Breithaupt, Kyle C. Cavanaugh, Just Cebrian, Karen Cummins, Donna J. Devlin, Jacob Doty, William L. Ellis, Ilka C. Feller, Christopher A. Gabler, Yiyang Kang, David A. Kaplan, John Paul Kennedy, Ken Krauss, Margaret Lamont, Kam-biu Liu, Melinda Martinez, Ashley M. Matheny, Giovanna M. McClenachan, Karen L. McKee, Irving A. Mendelssohn, Thomas C. Michot, Christopher J. Miller, Jena A. Moon, Ryan P. Moyer, James A. Nelson, Richard O'Connor, James W. Pahl, Jonathan L. Pitchford, C. Edward Proffitt, Tracy Quirk, Kara R. Radabaugh, Whitney A. Scheffel, Delbert L. Smee, Caitlin M. Snyder, Eric Sparks, Kathleen M. Swanson, William C. Vervaeke, Carolyn A. Weaver, Jonathan A Willis, Erik S. Yando, Qiang Yao, A. Randall HughesSoil elevation change in mangrove forests and marshes of the greater Everglades: A regional synthesis of surface elevation table-marker horizon (SET-MH) data
Coastal wetlands adapt to rising seas via feedbacks that build soil elevation, which lead to wetland stability. However, accelerated rates of sea-level rise can exceed soil elevation gain, leading to wetland instability and loss. Thus, there is a pressing need to better understand regional and landscape variability in rates of wetland soil elevation change. Here, we conducted a regional synthesisAuthorsLaura Feher, Michael Osland, Karen L. McKee, Kevin R.T. Whelan, Carlos A. Coronado-Molina, Fred H. Sklar, Ken Krauss, Rebecca Howard, Donald Cahoon, James C. Lynch, Lukas Lamb-Wotton, Tiffany G. Troxler, Jeremy R. Conrad, Gordon Anderson, William C. Vervaeke, Thomas J. Smith III, Nicole Cormier, Andrew From, Larry AllainPresence of the herbaceous marsh species Schoenoplectus americanus enhances surface elevation gain in transitional coastal wetland communities exposed to elevated CO2 and sediment deposition events
Coastal wetlands are dynamic ecosystems that exist along a landscape continuum that can range from freshwater forested wetlands to tidal marsh to mudflat communities. Climate-driven stressors, such as sea-level rise, can cause shifts among these communities, resulting in changes to ecological functions and services. While a growing body of research has characterized the landscape-scale impacts ofAuthorsCamille Stagg, Claudia Laurenzano, William C. Vervaeke, Ken Krauss, Karen L. McKeeThe history of surface-elevation paradigms in mangrove biogeomorphology
Positioned in the intertidal zone, mangrove forests are a key model ecosystem with which to observe and test biogeomorphological concepts. Understanding how mangroves interact with their intertidal environment, particularly tidal inundation, is important if we are to assess their vulnerability or resilience to accelerated sea-level rise. While various biogeomorphological processes are now well stuAuthorsDaniel A. Friess, Karen L. McKeeDoes geomorphology determine vulnerability of mangrove coasts to sea-level rise?
The greatest climate-based threat to coastlines worldwide is sea-level rise. We tested the hypothesis that tropical coasts fringed by mangroves and receiving high inputs of terrigenous sediment are less vulnerable to sea-level rise than biogenic systems dependent upon peat formation for vertical land development. An analysis of published data spanning a range of geomorphic settings showed that minAuthorsKaren L. McKee, Ken Krauss, Donald CahoonHow plants influence resilience of salt marsh and mangrove wetlands to sea-level rise
This review evaluates the importance of plants and associated biological processes in determining the vulnerability of coastal wetlands to sea-level rise. Coastal wetlands occur across a broad sedimentary continuum from minerogenic to biogenic, providing an opportunity to examine the relative importance of biological processes in wetland resilience to sea-level rise. We explore how plants influencAuthorsDonald R. Cahoon, Karen L. McKee, James MorrisThe field trip that changed the course of my career
After gobbling down a breakfast of sliced papaya, scrambled eggs, refried beans, and soft flour tacos, we gathered our gear and loaded it into the red zodiac that the station manager had assigned to us. My colleagues and I were headed to a pair of islands off the coast of Belize called Twin Cays, occupied by a unique group of tropical plants and animals adapted to a wet and saline habitat. Our rAuthorsKaren L. McKeeHurricane sedimentation in a subtropical salt marsh-mangrove community is unaffected by vegetation type
Hurricanes periodically deliver sediment to coastal wetlands, such as those in the Mississippi River Delta Complex (MRDC), slowing elevation loss and improving resilience to sea-level rise. However, the amount of hurricane sediment deposited and retained in a wetland may vary depending on the dominant vegetation. In the subtropical climate of the MRDC, the black mangrove (Avicennia germinans) hasAuthorsKaren L. McKee, Irving A. Mendelssohn, Mark W. HesterThe shifting saltmarsh-mangrove ecotone in Australasia and the Americas
Mangroves and saltmarshes coexist in the intertidal wetlands of many temperate and subtropical coastlines. In these settings, mangroves may be close to physiological limits of tolerance in relation to a range of environmental variables, including temperature, salinity, aridity, and inundation frequency. Changes in the distribution of mangrove and saltmarsh might thereby provide insights into the eAuthorsNeil Saintilan, Kerrylee Rogers, Karen L. McKeeWill fluctuations in salt marsh–mangrove dominance alter vulnerability of a subtropical wetland to sea‐level rise?
To avoid submergence during sea-level rise, coastal wetlands build soil surfaces vertically through accumulation of inorganic sediment and organic matter. At climatic boundaries where mangroves are expanding and replacing salt marsh, wetland capacity to respond to sea-level rise may change. To compare how well mangroves and salt marshes accommodate sea-level rise, we conducted a manipulative fieldAuthorsKaren L. McKee, William VervaekeAssessing coastal wetland vulnerability to sea-level rise along the northern Gulf of Mexico coast: Gaps and opportunities for developing a coordinated regional sampling network
Coastal wetland responses to sea-level rise are greatly influenced by biogeomorphic processes that affect wetland surface elevation. Small changes in elevation relative to sea level can lead to comparatively large changes in ecosystem structure, function, and stability. The surface elevation table-marker horizon (SET-MH) approach is being used globally to quantify the relative contributions of proAuthorsMichael J. Osland, Kereen T. Griffith, Jack C. Larriviere, Laura C. Feher, Donald R. Cahoon, Nicholas M. Enwright, David A. Oster, John M. Tirpak, Mark S. Woodrey, Renee C. Collini, Joseph J. Baustian, Joshua L. Breithaupt, Julia A Cherry, Jeremy R. Conrad, Nicole Cormier, Carlos A. Coronado-Molina, Joseph F. Donoghue, Sean A. Graham, Jennifer W. Harper, Mark W. Hester, Rebecca J. Howard, Ken W. Krauss, Daniel Kroes, Robert R. Lane, Karen L. McKee, Irving A. Mendelssohn, Beth A. Middleton, Jena A. Moon, Sarai Piazza, Nicole M. Rankin, Fred H. Sklar, Gregory D. Steyer, Kathleen M. Swanson, Christopher M. Swarzenski, William Vervaeke, Jonathan M Willis, K. Van WilsonSpecies and tissue type regulate long-term decomposition of brackish marsh plants grown under elevated CO2 conditions
Organic matter accumulation, the net effect of plant production and decomposition, contributes to vertical soil accretion in coastal wetlands, thereby playing a key role in whether they keep pace with sea-level rise. Any factor that affects decomposition may affect wetland accretion, including atmospheric CO2 concentrations. Higher CO2 can influence decomposition rates by altering plant tissue cheAuthorsJoshua A Jones, Julia A Cherry, Karen L. McKee