Karen L McKee

Research Ecologist

Short Biography

Dr. Karen McKee is an ecologist at the National Wetlands Research Center in Lafayette, LA. Her general research area is in the field of wetland plant ecology, particularly salt marsh and mangrove ecosystems. She has studied various aspects of wetlands, most recently focusing on the biophysical processes controlling adjustment of wetlands to changing sea level. Her research program includes field, greenhouse, and laboratory experiments designed to understand cause and effect relationships--information that is necessary to guide conservation, management, and restoration of wetland ecosystems.

Publications

Brix, H. B. Lorenzen, I. A. Mendelssohn, K.L. McKee, S.L. Miao. 2010. Can differences in phosphorus uptake kinetics explain the distribution of cattail and sawgrass in the Florida Everglades? BMC Plant Biology 10: 23-37. [Link]

Feller, I.C., C.E. Lovelock, U. Berger, K.L. McKee, S.B. Joye, and M.C. Ball. 2010. Biocomplexity in mangrove ecosystems. Annual Review of Marine Science 2: 395-417. [Link]

McKee, K.L. 2010. Fieldwork in New Zealand will facilitate comparison between Northern and Southern hemisphere wetlands. Soundwaves (Aug-Sep Issue): 7-9. [Link]

Li, S., J. Lissner, I.A. Mendelssohn, H. Brix, B. Lorenzen, K.L. McKee, and S.L. Miao. 2009. Nutrient and growth responses of cattail (Typha domingensis) to redox intensity and phosphate availability. Annals of Botany 105 (1): 175-184. [Link]

McKee, K.L. 2009. Belize fieldwork shows how oceanic mangrove islands kept up with sea-level rise for 8,000 years. Soundwaves 121: 11-13. [Link]

McKee, K.L. 2009. The SWS Research Brief: A new publication for non-technical audiences. Wetland Science and Practice: 26(2): 12-15. [Link]

McKee, K.L. 2009. Elevated CO2 may help coastal wetlands keep pace with sea-level rise. Soundwaves 115: 1-3. [Link]

McKee, K.L., B.A. Middleton, C.E. Proffitt, and D.J. Devlin. 2009. Perspectives on mosquito impoundments in eastern Florida: Reply to Rey et al. (2009). Marine Ecology Progress Series 389: 301-306. [Link]

McKee, K.L. and W. C. Vervaeke. 2009. Impacts of human disturbance on soil erosion and habitat stability of mangrove-dominated islands in the Pelican Cays and Twin Cays Ranges, Belize. Smithsonian Institution Marine Science Network Proceedings 33: 415-428. [Link]

Langley, J.A., K.L. McKee, D.R. Cahoon, J.A. Cherry, and J.P. Megonigal. 2009. Elevated CO2 stimulates marsh elevation gain, counterbalancing sea-level rise. Proceedings National Academy of Sciences 106(15): 6081-6086. [Link]

McKee, K.L. and J.A. Cherry. 2009. Hurricane Katrina sediment slowed elevation loss in subsiding brackish marshes of the Mississippi River delta. Wetlands 29: 2-15. [Link]

Cherry, J.A., K.L. McKee, and J.B. Grace. 2009. Elevated CO2 enhances biological contributions to elevation change in coastal wetlands by offsetting stressors associated with sea-level rise. Journal of Ecology 97: 67-77. [Link]

Middleton, B.A., D. Devlin, C.E. Proffitt, K.L. McKee, and K. Foster-Cretini. 2008. Characteristics of mangrove swamps managed for mosquito control in eastern Florida. Marine Ecology Progress Series 317: 117-129. [Link]

Krauss, K.W., C. M. Lovelock, K. L. McKee, L. López-Hoffman, S. M.L. Ewe, W.P. Sousa. 2008. Environmental drivers in mangrove establishment and early development. Aquatic Botany 89 (2) Special Issue: 105-127. [Link]

Lee, R.Y., W.P. Porubsky, I.C. Feller, K.L. McKee, and S.B. Joye. 2008. Porewater biogeochemistry and soil metabolism in dwarf red mangrove habitats (Twin Cays, Belize). Biogeochemistry 87: 181-198. [Link]

McKee, K.L and J.E. Rooth. 2008. Where temperate meets tropical: multifactorial effects of elevated CO2, nitrogen enrichment, and competition on a mangrove-salt marsh community. Global Change Biology 14 (5): 971-984. [Link]

McKee, K.L., J.E. Rooth, and I.C. Feller. 2007. Mangrove recruitment after forest disturbance is facilitated by herbaceous species common to the Caribbean Region. Ecological Applications 17(6): 1678-1693. [Link]

McKee, K.L., D.R. Cahoon, and I.C. Feller. 2007. Caribbean mangroves adjust to rising sea-level through biotic controls on change in soil elevation. Global Ecology and Biogeography 16: 545-556. [Link]

Feller, I.C., C.E. Lovelock, and K.L. McKee. 2007. Nutrient addition differentially affects ecological processes of Avicennia germinans in nitrogen vs. phosphorus limited mangrove ecosystems. Ecosystems 10: 347-359. [Link]

McKee, Karen L.; Mendelssohn, Irving A.; Materne, Michael D., 2006. Salt marsh dieback in coastal Louisiana: survey of plant and soil conditions in Barataria and Terrebonne basins, June 2000-September 2001. Open-File Report 2006-1167, x, 71 p. [Link]

Guntenspergen, G.; McKee, K.; Cahoon, D.; Grace, J.; Megonigal,P, 2006. Predicting the persistence of coastal wetlands to global change stressors. Australian Marine Sciences Association and Society of Wetland Scientists , Australian Marine Sciences Association and Society of Wetland Scientists

McKee, Karen, 2006. Potential Effects of Elevated Atmospheric Carbon Dioxide (CO2) on Coastal Wetlands. Geological Survey (U.S.) Fact Sheet 2006-3074, 3 p. [Link]

Feller, I.C., C.E. Lovelock, K.L. McKee, and R. Thompson. 2005. Variation in mangrove forest structure in Bocas del Toro, Republic of Panamá. J. of Caribbean Science 41 (3): 456-464. [Link]

Middleton, B.A. and K.L. McKee. 2005. Primary production in an impounded baldcypress swamp (Taxodium distichum) at the northern limit of the range. Wetland Ecology and Management 13: 15-24. [Link]

McKee, Karen L., 2004. Belowground Dynamics in Mangrove Ecosystems. Geological Survey (U.S.) Fact Sheet 2004-3126, 4 p. [Link]

McKee, Karen L., 2004. Global Change Impacts on Mangrove Ecosystems. Geological Survey (U.S.) Fact Sheet 2004-3125, 3 p. [Link]

Middleton, Beth A.; McKee, Karen, 2004. Latitudinal Variation in Carbon Storage Can Help Predict Changes in Swamps Affected by Global Warming. Geological Survey (U.S.) Fact Sheet 2004-3019, 4 p. [Link]

McKee, Karen L., 2004. Nutrient Controls on Biocomplexity of Mangrove Ecosystems. Geological Survey (U.S.) Fact Sheet 2004-3124, 3 p. [Link]

Middleton, B.A. and K.L. McKee. 2004. Use of a latitudinal gradient in bald cypress (Taxodium distichum) production to examine physiological controls on biotic boundaries and potential responses to environmental change. Global Ecology and Biogeography 13(3): 247-258. [Link]

Lovelock, C.E., I.C. Feller, K.L. McKee, B.M.J. Engelbrecht, and M.C. Ball. 2004. The effect of nutrient limitation on growth, photosynthesis, and hydraulic conductance of dwarf mangroves in Panama. Functional Ecology 18: 25-33. [Link]

McKee, K.L., I.A. Mendelssohn, and M.D. Materne. 2004. Acute salt marsh dieback in the Mississippi River deltaic plain: a drought-induced phenomenon? Global Ecology and Biogeography 13(1): 65-73. [Link]

McKee, Karen L.; McGinnis, Thomas E., II, 2003. Hurricane Mitch: effects on mangrove soil characteristics and root contributions to soil stabilization. Open-File Report 2003-178, 58 p.

McKee, K.L. 2003. Mangrove Ecology, Silviculture and Conservation. Book Review. Quarterly Review of Biology 78: 501-502.

Cahoon, D.R., P. Hensel, J. Rybczyk, K.L. McKee, C.E. Proffitt, and B. Perez. 2003. Mass tree mortality leads to mangrove peat collapse at Bay Islands, Honduras after Hurricane Mitch. J. Ecology 91: 1093-1105. [Link]

Lissner J, Mendelssohn IA, Lorenzen B, Brix H, McKee KL, Miao SL. 2003. Interactive effects of redox intensity and phosphate availability on growth and nutrient relations of Cladium jamaicense (Cyperaceae). Amer. J. Bot. 90 (5): 736-748 [Link]

Feller, I.C., D.F. Whigham, K.L. McKee and C.E. Lovelock. 2003. Nitrogen limitation of growth and nutrient dynamics in a disturbed mangrove forest, Indian River Lagoon, Florida. Oecologia 134: 405-414. [Link]

Feller, I.C., K.L. McKee,D. F. Whigham,.and J. P. O’Neill. 2003. Nitrogen vs phosphorus limitation across an ecotonal gradient in a mangrove forest. Biogeochemistry 62: 145-175. [Link]

Kuhn N.L., I.A. Mendelssohn, K.L. McKee, B. Lorenzen, H. Brix, and S. Miao. 2002. Root phosphatase activity in Cladium jamaicense and Typha domingensis grown under ambient and elevated phosphorus levels. Wetlands 22: 794-800. [Link]

McKee, K.L., I.C. Feller, M. Popp, and W. Wanek. 2002. Mangrove isotopic fractionation (d15N and d13C) across a nitrogen versus phosphorus limitation gradient. Ecology 83(4): 1065-1075. [Link]

McKee, K.L. 2001. Root proliferation in decaying roots and old root channels: a nutrient conservation mechanism in oligotrophic mangrove forests? J. Ecology 89(5): 876-887. [Link]

Middleton, B.A. and K.L. McKee. 2001. Degradation of mangrove tissues and implications for peat formation in Belizean island forests. J. Ecology 89(5): 818-828. [Link]

Lorenzen, B., H. Brix, I.A. Mendelssohn, K.L. McKee, and S.L. Miao. 2001. Growth, biomass allocation and nutrient use efficiency in Cladium jamaicense and Typha domingensis as affected by phosphorus and oxygen availability. Aquatic Bot. 70: 117-133. [Link]

Mendelssohn IA, McKee KL, Kong T. 2001. A comparison of physiological indicators of sublethal cadmium stress in wetland plants. Environmental and Experimental Botany 46 (3): 263-275. [Link]

Hester M.W., I.A. Mendelssohn, and K.L McKee. 2001. Species and population variation to salinity stress in Panicum hemitomon, Spartina patens, and Spartina alterniflora: morphological and physiological constraints. Environmental and Experimental Botany 46 (3): 277-297. [Link]

Chabbi, A.; McKee, K.L.; Mendelssohn, I.A., 2000. Fate of oxygen losses from Typha domingensis (Typhaceae) and Cladium jamaicense (Cyperaceae) and consequences for root metabolism. , p. 1081-1090 [Link]

Sorrell, B.K, I. A. Mendelssohn, K.L. McKee, and R.A. Woods. 2000. Ecophysiology of wetland plant roots: Modelling of aeration in relation to distribution. Annals of Botany 86(3): 675-685. [Link]

Mendelssohn, I. A. and McKee, K. L.  2000.  Saltmarshes and mangroves. pp.501-536  In M. Barbour and W. D. Billings (eds.), North American Terrestrial Vegetation, 2nd edition, Cambridge University Press, Cambridge.

Chabbi, A., K.L. McKee, and I.A. Mendelssohn. 2000. Fate of oxygen losses from Typha domingensis (Typhaceae) and Cladium jamaicense (Cyperaceae) and consequences for root metabolism. American Journal of Botany 87: 1081-1090.

McKee, K.L. and P.L. Faulkner. 2000.  Restoration of biogeochemical function in mangrove forests.  Restoration Ecology 8(3): 247-259.

McKee, K.L. and P.L. Faulkner.  2000. Mangrove peat analysis and reconstruction of vegetation history at the Pelican Cays, Belize. Atoll Research Bulletin 468: 46-58.

Lorenzen, B., H. Brix, K.L. McKee, I.A. Mendelssohn, and S. Miao.  2000. Seed germination of two Everglades species, Cladium jamaicense and Typha domingensis.  Aquatic Botany 66: 169-180.

McKee, K. L. and Baldwin, A. H. 1999. Disturbance regimes in North American wetlands. pp.331-363 In L.R. Walker (ed), Ecosystems of Disturbed Ground, Ecosystems of the World 16. Elsevier, Amsterdam.

Feller, I.C., D.F. Whigham, J.P. O'Neill, and K.L. McKee.  1999.  Within stand nutrient cycling in wetland ecosystems.  Ecology 80 (7):  2193-2205.

Feller, I. C. and K. L. McKee. 1999. Light-gap creation in Belizean mangrove forests by a wood-boring insect.  Biotropica 31(4): 607-617.

Hester M.W., Mendelssohn I.A., McKee K.L. 1998.  Intraspecific variation in salt tolerance and morphology in Panicum hemitomon and Spartina alterniflora. International Journal of Plant Sciences 159 (1): 127-138.

Publications before entry on duty are below this line

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Ewing, K., K. L. McKee, and I. A. Mendelssohn. 1997. A field comparison of indicators of sub-lethal stress in the salt-marsh grass, Spartina patens. Estuaries 20(1): 48-65.

Lessmann, J. M., I. A. Mendelssohn, M. W. Hester, and K. L. McKee. 1997. Population variation in growth response to flooding of three marsh grasses. Ecological Engineering 8: 31-47.

Patterson, S., K. L. McKee, and I. A. Mendelssohn. 1997. Effects of tidal inundation and predation on Avicennia germinans seedling establishment and survival in a subtropical salt marsh/mangal ecosystem. Mangroves and Salt Marshes 1: 103-111.

Hester, M. W., I. A. Mendelssohn, and K. L. McKee. 1996. Intraspecific variation in salt tolerance and morphology in the coastal grass Spartina patens (Poaceae). American Journal of Botany 83(12): 1521-1527.

McKee, K.L. 1996. Growth and physiological responses of mangrove seedlings to root zone anoxia. Tree Physiology 16: 883-889.

McKee, K.L. 1996. Mangrove ecosystems: definitions, distribution, zonation, forest structure, trophic structure, and ecological significance. Pp. 1-8 In Mangrove Ecology Workshop Manual, I.C. Feller (ed), Smithsonian Institution, Washington, DC.

McKee, K.L. 1996. Adaptations to environmental extremes in mangrove flora. Pp. 41-46. In Mangrove Ecology Workshop Manual, I.C. Feller (ed), Smithsonian Institution, Washington, DC.

Baldwin, A. H., I. A. Mendelssohn, and K. L. McKee. 1996. The influence of vegetation, salinity, and inundation on seed banks of oligohaline coastal marshes. American Journal of Botany 83(4): 470-479.

Broome, S. W., I. A. Mendelssohn, and K. L. McKee. 1995. Relative growth of Spartina patens (Ait.) Muhl. and Scirpus olneyi Gray occurring in a mixed stand as affected by salinity and flooding. Wetlands 15(1): 20-30.

Ewing, K., K. L. McKee, I. A. Mendelssohn, and M. W. Hester. 1995. A comparison of indicators of sublethal nutrient stress in the salt marsh grass, Spartina patens. Environmental and Experimental Botany 35 (3): 331-343.

Ewing, K., K. L. McKee, I. A. Mendelssohn, and M. H. Hester. 1995. A comparison of sub-lethal stress in the salt marsh grass, Spartina patens (Ait.) Muhl. Aquatic Botany 52: 59-74.

Flynn, K. M., K. L. McKee, and I. A. Mendelssohn. 1995. Recovery of freshwater marsh vegetation after a saltwater intrusion event. Oecologia 103: 63-72.

McKee, K. L. 1995. Mangrove species distribution patterns and propagule predation in Belize: an exception to the dominance-predation hypothesis. Biotropica 27(3):  334- 345.

McKee, K. L. 1995. Seedling recruitment patterns in a Belizean mangrove forest: effects of establishment ability and physico-chemical factors. Oecologia 101: 448-460.

McKee, K. L. 1995. Interspecific variation in growth, biomass partitioning, and defensive characteristics of neotropical mangrove seedlings: Response to availability of light and nutrients. American Journal of Botany 82(3): 299-307.

Hester, M. W., K. L. McKee, D. M. Burdick, M. S. Koch, K. M. Flynn, S. Patterson, and I. A. Mendelssohn. 1994. Clonal integration in Spartina patens across a nitrogen and salinity gradient. Canadian Journal of Botany 72: 767-770.

McKee, K. L. 1993. Soil physicochemical patterns and mangrove species distribution: reciprocal effects? Journal of Ecology 81: 477-487.

McKee, K. L. 1993. Determinants of mangrove species distribution patterns in neotropical forests: biotic and abiotic factors affecting seedling survival and growth. Louisiana State University, Ph. D. Dissertation. 247 pp.

Wilsey, B. J., K. L. McKee, and I. A. Mendelssohn. 1992. Effects of increased elevation and macro- and micronutrient additions on Spartina alterniflora transplant success in saltmarsh dieback areas in Louisiana. Environmental Management 16: 505-11.

Naidoo, G., K. L. McKee, and I. A. Mendelssohn. 1992. Anatomical and metabolic responses to waterlogging and salinity in Spartina alterniflora and S. patens. American Journal of Botany 79(7): 765-770.

Mendelssohn, I. A. and McKee, K. L. 1992. Indicators of environmental stress in wetland plants. In McKenzie et al. (eds.), Ecological Indicators, Elsevier Science Publ., Essex, pp.603-624.

Koch, M., I. A. Mendelssohn, and K. L. McKee. 1990. Mechanism for the hydrogen sulfide-induced growth limitation in wetland macrophytes. Limnology and Oceanography 35(2): 399-408.

Burdick, D. M., I. A. Mendelssohn, and K. L. McKee. 1989. Production and metabolism of the marsh grass Spartina patens as related to edaphic factors in a brackish, mixed marsh community in Louisiana. Estuaries 12:195-204.

Feijtel, T. C., P. A. Moore, K. L. McKee, and I. A. Mendelssohn. 1989. Salinity and flooding level as determinants of soil solution composition and nutrient content in Panicum hemitomon. Plant and Soil 114:197-204.

McKee, K. L. and I. A. Mendelssohn. 1989. Response of a freshwater marsh plant community to increased salinity and water level. Aquatic Botany 34: 301-316.

McKee, K. L., I. A. Mendelssohn, and D. M. Burdick. 1989. Effect of long-term flooding on root metabolic response in five freshwater marsh plant species. Canadian Journal of Botany 67: 3446-3452.

Mendelssohn, I. A. and K. L. McKee. 1988. Spartina alterniflora die-back in Louisiana: Time-course investigation of soil waterlogging effects. Journal of Ecology 76: 509-521.

McKee, K. L., I. A. Mendelssohn, and M. W. Hester. 1988. Reexamination of pore water sulfide concentrations and redox potentials near the aerial roots of Rhizophora mangle and Avicennia germinans. American Journal of Botany 75:1352-1359.

McKee, K. L. and W. H. Patrick, Jr. 1988. The relationship of smooth cordgrass (Spartina alternifiora) to tidal datums: A review. Estuaries 11:143-151.

McKee, K. L. and I. A. Mendelssohn. 1987. Root metabolism in the black mangrove, Avicennia germinans (L.) L.: Response to hypoxia. Environmental and Experimental Botany 27:147-156.

Mendelssohn, I. A. and McKee, K. L. 1987. Root metabolic response of Spartina alterniflora to hypoxia In R.M.M. Crawford (ed), Plant Life in Aquatic and Amphibious Habitats, Blackwell, Oxford, pp.239-53.

Mendelssohn, I. A. and K. L. McKee. 1985. The effect of nutrients on adenine nucleotide levels and adenylate energy charge ratio in Spartina alterniflora and S. patens. Plant Cell and Environment 8: 213-218.

McKee, K. L. and I. A. Mendelssohn. 1984. The influence of season on adenine nucleotide concentrations and energy charge in four marsh plant species. Physiologia Plantarum 62:1-7.

Pedrazzini, F. and K. L. McKee. 1984. Effect of flooding on activities of soil dehydrogenases and alcohol dehydrogenase in rice (Oryza sativa L.) roots. Soil Science and Plant Nutrition 30: 359-366.

Sklar, F. H. and K. L. McKee. 1984. Adenylate energy charge (AEC) response to stress and extraction technique in the Louisiana swamp crayfish, Procambarus clarkii. Bulletin of Environmental Contamination and Toxicology 33: 584-591.

Mendelssohn, I. A., R.E. Turner, and K. L. McKee. 1983. Louisiana's eroding coastal zone:  management alternatives. Journal of the Limnological Society of Southern Africa 9(2): 63-75.

Turner, R. E. , K. L. McKee, W. B. Sikora, J. P. Sikora, I. A. Mendelssohn, E. Swenson, C. Neill, S. g. Leibowitz, and F. R. Pedrazzini. 1983. The impact and mitigation of man-made canals in coastal Louisiana. Water Science and Technology 16:  497-504.

McKee, K. L. and E. D. Seneca. 1982. The influence of morphology in determining the decomposition of two salt marsh macrophytes. Estuaries 5: 302-309.

Mendelssohn, I. A., McKee, K. L. and Postek, M. T. 1982. Sublethal stresses controlling Spartina alterniflora productivity. In B. Gopal, R.E. Turner, R.G. Wetzel, and D.F. Whigham, (eds), Wetlands: Ecology and Management, National Institute of Ecology, Jaipur, India, pp.223-42.

Mendelssohn, I. A. and K. L. McKee. 1981. Determination of adenine nucleotide levels and energy charge ratio in two Spartina species. Aquatic Botany 11: 37-55.

Mendelssohn, I. A., K. L. McKee and W. H. Patrick, Jr. 1981. Oxygen deficiency in Spartina alterniflora roots: Metabolic adaptation to anoxia. Science 214: 439-441.

McKee, K. L. 1977. Decomposition of Spartina alterniflora and Juncus roemerianus. North Carolina State University, M. S. Thesis. 105 pp.

My Science Topics

My USGS Science Strategy Areas

My main research focus is on how wetlands are affected by and respond to global change factors such as sea-level rise, elevated atmospheric CO2 (carbon dioxide), weather extremes, and hurricane disturbance.  Much of this work addresses the complex interrelationships among plants, animals, and their environment (biocomplexity) and the emergent properties of ecosystems that arise from these feedback processes--properties such as resilience to disturbance and habitat stability.

Acceleration in sea-level rise (SLR) threatens low-lying coastal areas and the extensive wetland habitat located within these areas.  I am investigating how elevated concentrations of atmospheric CO2 (carbon dioxide) may interact with other factors such as flooding and salinity to alter wetland ecosystems and their capacity to accommodate SLR.  This work is carried out in the Wetland Elevated CO2 Experimental Facility located at the National Wetlands Research Center, Lafayette, LA.  Mesocosms containing intact sections of marsh are exposed to different conditions representing future scenarios of climate, CO2, and sea level.  Complimenary field studies are also carried out to relate experimental findings with how these ecosystems accrete vertically in response to SLR.

Videos highlighting this research can be found here:

Impacts of Sea-Level Rise on Coastal Wetlands in the Mississippi River Delta

Hurricane Impacts on Marsh and Mangrove Ecosystems

Potential Effects of Rising CO2 and Climate Change on Coastal Wetlands

Sea-Level Rise, Subsidence, and Wetland Loss