Response and Recovery of Low-Salinity Marsh Plant Communities to Presses and Pulses of Elevated Salinity

  • Fan LiEmail author
  • Steven C. Pennings


In estuaries, future variation in sea level and river discharge will lead to saline intrusion into low-salinity tidal marshes. To investigate the processes that control the differential response and recovery of tidal freshwater marsh plant communities to saline pulses, a 3 × 5 factorial greenhouse experiment was conducted to examine the effects of a range of salinity levels (3, 5, and 10 practical salinity units (PSU)) and pulse durations (5, 10, 15, 20, and 30 days per month) on community composition of tidal freshwater marsh vegetation. Recovery of perturbed communities was also examined after 10 months. The results showed that community composition was increasingly affected by the more-saline and longer-duration treatments. The increasing suppression of salt-sensitive species resulted in species reordering, decreased species richness, and decreased aboveground biomass. Most of the plant species were able to recover from low-salinity, short-duration saline pulses in less than 1 year. However, because not all species recovered in the heavily salinized treatments, species richness at the end of the recovery period remained low for treatments that were heavily salinized during the treatment period. In contrast, plant aboveground biomass fully recovered in the heavily salinized treatments. Although the magnitude and duration of pulsed environmental changes had strong effects on community composition, shifts in community composition prevented long-term reductions in productivity. Thus, in this study system, environmental change affected species composition more strongly than it did ecosystem processes.


Disturbance Salinization Freshwater marsh Composition Productivity 



This material is based upon work supported by the National Science Foundation through the Georgia Coastal Ecosystems Long-Term Ecological Research program under Grant No. OCE-1237140 and a Sigma Xi Grant-in-Aid-of-Research. We thank Wei-Ting Lin, Shanze Li, Jacob Shalack, Caroline Reddy, Dontrece Smith, Timothy Montgomery, Sasha Greenspan, Eric Weingarten, Narissa Turner, Jonathan Adams, and GCE-LTER Schoolyard participants for help with this project. This is contribution number 1074 from the University of Georgia Marine Institute.

Author’s Contributions

FL and SCP conceived and designed the experiments. FL performed the experiments and analyzed the data. FL and SCP wrote the manuscript.

Supplementary material

12237_2018_490_MOESM1_ESM.docx (148 kb)
ESM 1 (DOCX 148 kb)


  1. Ardón, M., J.L. Morse, B.P. Colman, and E.S. Bernhardt. 2013. Drought-induced saltwater incursion leads to increased wetland nitrogen export. Global Change Biology 19 (10): 2976–2985.CrossRefGoogle Scholar
  2. Barendregt, A., and C. Swarth. 2013. Tidal freshwater wetlands: variation and changes. Estuaries and Coasts 36 (3): 445–456.CrossRefGoogle Scholar
  3. Ciais, P., M. Reichstein, N. Viovy, A. Granier, J. Ogee, V. Allard, M. Aubinet, N. Buchmann, C. Bernhofer, A. Carrara, F. Chevallier, N. De Noblet, A.D. Friend, P. Friedlingstein, T. Grunwald, B. Heinesch, P. Keronen, A. Knohl, G. Krinner, D. Loustau, G. Manca, G. Matteucci, F. Miglietta, J.M. Ourcival, D. Papale, K. Pilegaard, S. Rambal, G. Seufert, J.F. Soussana, M.J. Sanz, E.D. Schulze, T. Vesala, and R. Valentini. 2005. Europe-wide reduction in primary productivity caused by the heat and drought in 2003. Nature 437 (7058): 529–533.CrossRefGoogle Scholar
  4. Cloern, J.E., and A.D. Jassby. 2012. Drivers of change in estuarine-coastal ecosystems: discoveries from four decades of study in San Francisco Bay. Reviews of Geophysics 50, 4.Google Scholar
  5. Collins, S.L., K.N. Suding, E.E. Cleland, M. Batty, S.C. Pennings, K.L. Gross, J.B. Grace, L. Gough, J.E. Fargione, and C.M. Clark. 2008. Rank clocks and plant community dynamics. Ecology 89 (12): 3534–3541.CrossRefGoogle Scholar
  6. Costanza, R., R. d'Arge, R. de Groot, S. Farber, M. Grasso, B. Hannon, K. Limburg, S. Naeem, R.V. O'Neill, J. Paruelo, R.G. Raskin, P. Sutton, and M. van den Belt. 1998. The value of the world's ecosystem services and natural capital. Ecological Economics 25 (1): 3–15.CrossRefGoogle Scholar
  7. Craft, C., J. Clough, J. Ehman, S. Joye, R. Park, S. Pennings, H. Guo, and M. Machmuller. 2009. Forecasting the effects of accelerated sea-level rise on tidal marsh ecosystem services. Frontiers in Ecology and the Environment 7 (2): 73–78.CrossRefGoogle Scholar
  8. Crain, C.M., L.K. Albertson, and M.D. Bertness. 2008. Secondary succession dynamics in estuarine marshes across landscape-scale salinity gradients. Ecology 89 (10): 2889–2899.CrossRefGoogle Scholar
  9. Crain, C. M., B. R. Silliman, S. L. Bertness, and M. D. Bertness. 2004. Physical and biotic drivers of plant distribution across estuarine salinity gradients. Ecology 85:2539-2549.Google Scholar
  10. Dieleman, C.M., B.A. Branfireun, J.W. McLaughlin, and Z. Lindo. 2015. Climate change drives a shift in peatland ecosystem plant community: implications for ecosystem function and stability. Global Change Biology 21 (1): 388–395.CrossRefGoogle Scholar
  11. Dijk, G.V., A.J.P. Smolders, R. Loeb, A. Bout, J.G.M. Roelofs, and L.P.M. Lamers. 2015. Salinization of coastal freshwater wetlands; effects of constant versus fluctuating salinity on sediment biogeochemistry. Biogeochemistry 126 (1–2): 71–84.CrossRefGoogle Scholar
  12. Donohue, I., H. Hillebrand, J.M. Montoya, O.L. Petchey, S.L. Pimm, M.S. Fowler, K. Healy, A.L. Jackson, M. Lurgi, D. McClean, N.E. O'Connor, E.J. O'Gorman, and Q. Yang. 2016. Navigating the complexity of ecological stability. Ecology Letters 19 (9): 1172–1185.CrossRefGoogle Scholar
  13. Flynn, K.M., K.L. McKee, and I.A. Mendelssohn. 1995. Recovery of freshwater marsh vegetation after a saltwater intrusion event. Oecologia 103 (1): 63–72.CrossRefGoogle Scholar
  14. Goodman, A.M., G.G. Ganf, G.C. Dandy, H.R. Maier, and M.S. Gibbs. 2010. The response of freshwater plants to salinity pulses. Aquatic Botany 93 (2): 59–67.CrossRefGoogle Scholar
  15. Guo, H., and S.C. Pennings. 2012. Mechanisms mediating plant distributions across estuarine landscapes in a low-latitude tidal estuary. Ecology 93 (1): 90–100.CrossRefGoogle Scholar
  16. Guo, H., K. Więski, Z. Lan, and S.C. Pennings. 2014. Relative influence of deterministic processes on structuring marsh plant communities varies across an abiotic gradient. Oikos 123 (2): 173–178.CrossRefGoogle Scholar
  17. Herbert, E.R., P. Boon, A.J. Burgin, S.C. Neubauer, R.B. Franklin, M. Ardón, K.N. Hopfensperger, L.P.M. Lamers, and P. Gell. 2015. A global perspective on wetland salinization: ecological consequences of a growing threat to freshwater wetlands. Ecosphere 6: 1–43.CrossRefGoogle Scholar
  18. Herbert, E. R., J. Schubauer-Berigan., and C. B. Craft. 2018. Differential effects of chronic and acute simulated seawater intrusion on tidal freshwater marsh carbon cycling. Biogeochemistry, 1–18.Google Scholar
  19. Hooper, D.U., and P.M. Vitousek. 1997. The effects of plant composition and diversity on ecosystem processes. Science 277 (5330): 1302–1305.CrossRefGoogle Scholar
  20. Hoover, D.L., A.K. Knapp, and M.D. Smith. 2014. Resistance and resilience of a grassland ecosystem to climate extremes. Ecology 95 (9): 2646–2656.CrossRefGoogle Scholar
  21. Hopfensperger, K., A. Burgin, V. Schoepfer, and A. Helton. 2014. Impacts of saltwater incursion on plant communities, anaerobic microbial metabolism, and resulting relationships in a restored freshwater wetland. Ecosystems 17 (5): 792–807.CrossRefGoogle Scholar
  22. Howard, R.J., and I.A. Mendelssohn. 1999a. Salinity as a constraint on growth of oligohaline marsh macrophytes. I. Species variation in stress tolerance. American Journal of Botany 86 (6): 785–794.CrossRefGoogle Scholar
  23. Howard, R.J., and I.A. Mendelssohn. 1999b. Salinity as a constraint on growth of oligohaline marsh macrophytes. II. Salt pulses and recovery potential. American Journal of Botany 86 (6): 795–806.CrossRefGoogle Scholar
  24. Howard, R.J., and I.A. Mendelssohn. 2000. Structure and composition of oligohaline marsh plant communities exposed to salinity pulses. Aquatic Botany 68 (2): 143–164.CrossRefGoogle Scholar
  25. Knighton, A.D., K. Mills, and C.D. Woodroffe. 1991. Tidal-creek extension and saltwater intrusion in northern Australia. Geology 19 (8): 831–834.CrossRefGoogle Scholar
  26. Li, F. 2017. Mesocosm experiment on fresh marsh plant community responses to salinity pulses in 2014 and 2015. Georgia Coastal Ecosystems LTER Project; University of Georgia; Long Term Ecological Research Network. doi:
  27. Li, F., and S. Pennings. 2018. Responses of tidal freshwater and brackish marsh macrophytes to pulses of saline water simulating sea level rise and reduced discharge. Wetlands: 1–7.Google Scholar
  28. Li, S., C.S. Hopkinson, J.P. Schubauer-Berigan, and S.C. Pennings. 2018. Climate drivers of Zizaniopsis miliacea biomass in a Georgia, U.S.A. tidal fresh marsh. Limnology and Oceanograpy 63 (5): 2266–2276. Scholar
  29. Ma, G., V.H. Rudolf, and C.S. Ma. 2015. Extreme temperature events alter demographic rates, relative fitness, and community structure. Global Change Biology 21 (5): 1794–1808.CrossRefGoogle Scholar
  30. Neubauer, S. 2013. Ecosystem responses of a tidal freshwater marsh experiencing saltwater intrusion and altered hydrology. Estuaries and Coasts 36 (3): 491–507.CrossRefGoogle Scholar
  31. Odum, W.E. 1988. Comparative ecology of tidal freshwater and salt marshes. Annual Review of Ecology and Systematics 19 (1): 147–176.CrossRefGoogle Scholar
  32. Pezeshki, S.R., R.D. De Laune, and W.H. Patrick. 1987. Response of the freshwater marsh species, Panicum hemitomon Schult., to increased salinity. Freshwater Biology 17 (2): 195–200.CrossRefGoogle Scholar
  33. Rejmánková, E.K. 1992. Ecology of creeping macrophytes with special reference to Ludwigia peploides (H.B.K.) Raven. Aquatic Botany 43 (3): 283–299.CrossRefGoogle Scholar
  34. Saintilan, N., N.C. Wilson, K. Rogers, A. Rajkaran, and K.W. Krauss. 2014. Mangrove expansion and salt marsh decline at mangrove poleward limits. Global Change Biology 20 (1): 147–157.CrossRefGoogle Scholar
  35. Sharpe, P.J., and A.H. Baldwin. 2012. Tidal marsh plant community response to sea-level rise: a mesocosm study. Aquatic Botany 101: 34–40.CrossRefGoogle Scholar
  36. Sklar, F.H., and J.A. Browder. 1998. Coastal environmental impacts brought about by alterations to freshwater flow in the Gulf of Mexico. Environmental Management 22 (4): 547–562.CrossRefGoogle Scholar
  37. Smith, M.D. 2011. An ecological perspective on extreme climatic events: a synthetic definition and framework to guide future research. Journal of Ecology 99 (3): 656–663.CrossRefGoogle Scholar
  38. Smith, M.D., A.K. Knapp, and S.L. Collins. 2009. A framework for assessing ecosystem dynamics in response to chronic resource alterations induced by global change. Ecology 90 (12): 3279–3289.CrossRefGoogle Scholar
  39. Spaak, J.W., J.M. Baert, D.J. Baird, N. Eisenhauer, L. Maltby, F. Pomati, V. Radchuk, J.R. Rohr, P.J. Van den Brink, and F. De Laender. 2017. Shifts of community composition and population density substantially affect ecosystem function despite invariant richness. Ecology Letters 20 (10): 1315–1324.CrossRefGoogle Scholar
  40. Sutter, L.A., R.M. Chambers, and J.E. Perry. 2015. Seawater intrusion mediates species transition in low salinity, tidal marsh vegetation. Aquatic Botany 122: 32–39.CrossRefGoogle Scholar
  41. Taguchi, Y.H., and Y. Oono. 2005. Relational patterns of gene expression via non-metric multidimensional scaling analysis. Bioinformatics 21 (6): 730–740.CrossRefGoogle Scholar
  42. Thibault, K.M., and J.H. Brown. 2008. Impact of an extreme climatic event on community assembly. Proceedings of the National Academy of Sciences 105 (9): 3410–3415.CrossRefGoogle Scholar
  43. Tilman, D., J. Knops, D. Wedin, P. Reich, M. Ritchie, and E. Siemann. 1997. The influence of functional diversity and composition on ecosystem processes. Science 277 (5330): 1300–1302.CrossRefGoogle Scholar
  44. Visser, J., C. Sasser, R. Chabreck, and R.G. Linscombe. 2002. The impact of a severe drought on the vegetation of a subtropical estuary. Estuaries 25 (6): 1184–1195.CrossRefGoogle Scholar
  45. Weston, N.B., R.E. Dixon, and S.B. Joye. 2006. Ramifications of increased salinity in tidal freshwater sediments: geochemistry and microbial pathways of organic matter mineralization. Journal of Geophysical Research: Biogeosciences 111 (G1): G01009.CrossRefGoogle Scholar
  46. White, S., and M. Alber. 2009. Drought-associated shifts in Spartina alterniflora and S. cynosuroides in the Altamaha River estuary. Wetlands 29 (1): 215–224.CrossRefGoogle Scholar
  47. Więski, K., H. Guo, C. Craft, and S. Pennings. 2010. Ecosystem functions of tidal fresh, brackish, and salt marshes on the Georgia coast. Estuaries and Coasts 33 (1): 161–169.CrossRefGoogle Scholar
  48. Winder, M., and D.E. Schindler. 2004. Climate change uncouples trophic interactions in an aquatic ecosystem. Ecology 85 (8): 2100–2106.CrossRefGoogle Scholar
  49. Woo, I., and J.Y. Takekawa. 2012. Will inundation and salinity levels associated with projected sea level rise reduce the survival, growth, and reproductive capacity of Sarcocornia pacifica (pickleweed)? Aquatic Botany 102: 8–14.CrossRefGoogle Scholar
  50. Wood, C., and G.A. Harrington. 2015. Influence of seasonal variations in sea level on the salinity regime of a coastal groundwater-fed wetland. Groundwater 53 (1): 90–98.CrossRefGoogle Scholar
  51. Zedler, J.B., and S. Kercher. 2005. Wetland resources: status, trends, ecosystem services, and restorability. Annual Review of Environment and Resources 30 (1): 39–74.CrossRefGoogle Scholar
  52. Zhou, M., K. Butterbach-Bahl, H. Vereecken, and N. Brüggemann. 2016. A meta-analysis of soil salinization effects on nitrogen pools, cycles and fluxes in coastal ecosystems. Global Change Biology 23: 1338–1352.CrossRefGoogle Scholar

Copyright information

© Coastal and Estuarine Research Federation 2018

Authors and Affiliations

  1. 1.Department of Biology and BiochemistryUniversity of HoustonHoustonUSA

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