Oceanography The Official Magazine of
The Oceanography Society
Volume 30 Issue 03

View Issue TOC
Volume 30, No. 3
Pages 48 - 59


Buried Alive or Washed Away: The Challenging Life of Mangroves in the Mekong Delta

By Sergio Fagherazzi , Karin R. Bryan, and William Nardin  
Jump to
Article Abstract Citation References Copyright & Usage
Article Abstract

Mangroves colonize tropical shorelines, protecting coastal communities and providing valuable ecosystem services. Mangroves associated with deltas cope with a very dynamic environment characterized by strong gradients in salinity, deposition triggered by sediment inputs, and erosion caused by waves and currents. Mangroves are adapted to this ever-changing landscape, with different species colonizing different elevations in response to inundation frequency. A series of feedbacks between hydrodynamics, sediment transport, and mangroves was observed in a fringe forest of the Mekong Delta, Vietnam. Sonneratia spp. rapidly encroach upon sandy areas because the stable substrate favors seedling establishment. In contrast, fewer seedlings are present in muddy locations where currents and waves frequently rework the bottom. Along muddy shorelines that are eroding, turbulence increases local scour near roots and trunks, undercutting the trees. Enhanced sediment accumulation due to delta progradation can smother the mangrove roots and lead to forest dieback. We find clear evidence that mangroves affect both hydrodynamics and sediment transport, thus engineering the landscape and enhancing sediment trapping and delta progradation. Sonneratia spp. are replaced by Aegiceras corniculatum, Avicennia marina, and Nypa fruticans when the seabed becomes high enough, indicating that ecological succession is present in a fast prograding deltaic environment. Thus, it is imperative to determine the small-scale feedbacks between mangroves, hydrodynamics, and sediment transport in order to build quantitative ecogeomorphic models of deltaic sedimentation that can be used to explain the distribution of mangrove species, the forest structure, and large-scale dynamics in a tropical deltaic setting.


Fagherazzi, S., K.R. Bryan, and W. Nardin. 2017. Buried alive or washed away: The challenging life of mangroves in the Mekong Delta. Oceanography 30(3):48–59, https://doi.org/10.5670/oceanog.2017.313.

    Adame, M.F., D. Neil, S.F. Wright, and C.E. Lovelock 2010. Sedimentation within and among mangrove forests along a gradient of geomorphological settings. Estuarine, Coastal and Shelf Science 86:21–30, https://doi.org/10.1016/​j.ecss.2009.10.013.
  1. Allison, M.A., C.A. Nittrouer, A.S. Ogston, J.C. Mullarney, and T.T. Nguyen. 2017. Sedimentation and survival of the Mekong Delta: A case study of decreased sediment supply and accelerating rates of relative sea level rise. Oceanography 30(3):98–109, https://doi.org/​10.5670/oceanog.2017.318.
  2. Alongi, D.M. 2008. Mangrove forests: Resilience, protection from tsunamis, and responses to global climate change. Estuarine, Coastal and Shelf Science 76(1):1–13, https://doi.org/10.1016/​j.ecss.2007.08.024.
  3. Alongi, D.M. 2012. Carbon sequestration in mangrove forests. Carbon Management 3(3):313–322, https://doi.org/10.4155/cmt.12.20.
  4. Balke, T., T.J. Bouma, P.M.J. Herman, E.M. Horstman, C. Sudtongkong, and E.L. Webb. 2013. Cross-shore gradients of physical disturbance in mangroves: Implications for seedling establishment. Biogeosciences 10:5,411–5,419, https://doi.org/​10.5194/bg-10-5411-2013.
  5. Balke, T., T.J. Bouma, E.M. Horstman, E.L. Webb, P.L. Erftemeijer, and P.M. Herman. 2011. Windows of opportunity: Thresholds to mangrove seedling establishment on tidal flats. Marine Ecology Progress Series 440:1–9, https://doi.org/10.3354/meps09364.
  6. Ball, M.C. 1980. Patterns of secondary succession in a mangrove forest of southern Florida. Oecologia 44(2):226–235, https://doi.org/10.1007/BF00572684.
  7. Bryan, K.R., W. Nardin, J.C. Mullarney, and S. Fagherazzi. In press. The role of cross-shore tidal dynamics in controlling intertidal sediment exchange in mangroves in Cù Lao Dung, Vietnam. Continental Shelf Research, https://doi.org/10.1016/​j.csr.2017.06.014.
  8. Bullock, E.L., S. Fagherazzi, W. Nardin, P. Vo-Luong, P. Nguyen, and C.E. Woodcock. In press. Temporal patterns in species zonation in a mangrove forest in the Mekong Delta, Vietnam, using a time series of Landsat imagery. Continental Shelf Research, https://doi.org/10.1016/j.csr.2017.07.007.
  9. Davis, J.H. 1940. The ecology and geologic role of mangroves in Florida. Carnegie Institution of Washington Publication 517:303–412.
  10. Eidam, E.F., C.A. Nittrouer, A.S. Ogston, D.J. DeMaster, J.P. Liu, T.T. Nguyen, T.N. Nguyen. In press. Dynamic controls on shallow clinoform geometry: Mekong Delta, Vietnam. Continental Shelf Research, https://doi.org/10.1016/j.csr.2017.06.001.
  11. Fagherazzi, S., D.A. Edmonds, W. Nardin, N. Leonardi, A. Canestrelli, F. Falcini, D. Jerolmack, G. Mariotti, J.C. Rowland, and R.L. Slingerland. 2015. Dynamics of river mouth deposits. Review of Geophysics 53:642–672, https://doi.org/​10.1002/​2014RG000451.
  12. Fagherazzi, S., M.L. Kirwan, S.M. Mudd, G.R. Guntenspergen, S. Temmerman, A. D’Alpaos, J. Koppel, J.M. Rybczyk, E. Reyes, C. Craft, and J. Clough. 2012. Numerical models of salt marsh evolution: Ecological, geomorphic, and climatic factors. Reviews of Geophysics 50, RG1002, https://doi.org/10.1029/2011RG000359.
  13. Fricke, A.T., C.A. Nittrouer, A.S. Ogston, and H.P. Vo-Luong. In press. Asymmetric progradation of a coastal mangrove forest controlled by combined fluvial and marine influence, Cù Lao Dung, Vietnam. Continental Shelf Research, https://doi.org/​10.1016/j.csr.2017.07.012.
  14. Friess, D.A., K.W. Krauss, E.M. Horstman, T. Balke, T.J. Bouma, D. Galli, and E.L. Webb. 2012. Are all intertidal wetlands naturally created equal? Bottlenecks, thresholds and knowledge gaps to mangrove and saltmarsh ecosystems. Biological Reviews 87(2):346–366, https://doi.org/10.1111/j.1469-185X.2011.00198.x.
  15. Henderson, S.M., B.K. Norris, J.C. Mullarney, and K.R. Bryan. In press. Wave-frequency flows within a near-bed vegetation canopy. Continental Shelf Research, https://doi.org/10.1016/j.csr.​2017.06.003.
  16. Hunt, S., K.R. Bryan, and J.C. Mullarney. 2015. The influence of wind and waves on the existence of stable intertidal morphology in meso-tidal estuaries. Geomorphology 228:158–174, https://doi.org/​10.1016/j.geomorph.2014.09.001.
  17. Kuenzer, C., A. Bluemel, S. Gebhardt, T.V. Quoc, and S. Dech. 2011. Remote sensing of mangrove ecosystems: A review. Remote Sensing 3(5):878–928, https://doi.org/10.3390/rs3050878.
  18. Lessa, G., and G. Masselink. 1995. Morphodynamic evolution of a macrotidal barrier estuary. Marine Geology 129:25–46, https://doi.org/10.1016/​0025-3227(95)00103-4.
  19. Li, L., X.H. Wang, F. Andutta, and D. Williams. 2014. Effects of mangroves and tidal flats on suspended-sediment dynamics: Observational and numerical study of Darwin Harbour, Australia. Journal of Geophysical Research 119(9):5,854–5,873, https://doi.org/10.1002/2014JC009987.
  20. Lovelock, C.E., B.K. Sorrell, N. Hancock, Q. Hua, and A. Swales. 2010. Mangrove forest and soil development on a rapidly accreting shore in New Zealand. Ecosystems 13(3):437–451, https://doi.org/10.1007/s10021-010-9329-2.
  21. Lugo, A.E. 1980. Mangrove ecosystems: Successional or steady state? Biotropica 65–72, https://doi.org/​10.2307/2388158.
  22. Massel, S.R., K. Furukawa, and R.M. Brinkman. 1999. Surface wave propagation in mangrove forests. Fluid Dynamics Research 24:219–249, https://doi.org/​10.1016/S0169-5983(98)00024-0.
  23. McKee, K.L. 1993. Soil physicochemical patterns and mangrove species distribution: Reciprocal effects? Journal of Ecology 81:477–487, https://doi.org/​10.2307/2261526.
  24. Mullarney, J.C., S.M. Henderson, B.K. Norris, K.R. Bryan, A.T. Fricke, D.R. Sandwell, and D.P. Culling. 2017. A question of scale: How turbulence around aerial roots shapes the seabed morphology in mangrove forests of the Mekong Delta. Oceanography 30(3):34–47, https://doi.org/​10.5670/oceanog.​2017.312.
  25. Mullarney, J.C., S.M. Henderson, J.A.H. Reyns, B.K. Norris, and K.R. Bryan. In press. Spatially varying drag within a wave-exposed mangrove forest and on the adjacent tidal flat. Continental Shelf Research, https://doi.org/10.1016/j.csr.2017.06.019.
  26. Nardin, W., S. Locatelli, V. Pasquarella, M.C. Rulli, C.E. Woodcock, and S. Fagherazzi. 2016a. Dynamics of a fringe mangrove forest detected by Landsat images in the Mekong River delta, Vietnam. Earth Surface Processes and Landforms 41:2,024–2,037, https://doi.org/10.1002/esp.3968.
  27. Nardin, W., C.E. Woodcock, and S. Fagherazzi. 2016b. Bottom sediments affect Sonneratia mangrove forests in the prograding Mekong Delta, Vietnam. Estuarine, Coastal and Shelf Science 177:60–70, https://doi.org/10.1016/j.ecss.2016.04.019.
  28. Norris, B.K., J.C. Mullarney, K.R. Bryan, and S.M. Henderson. In press. The effect of pneumatophore density on turbulence: A field study in a Sonneratia-dominated mangrove forest, Vietnam. Continental Shelf Research, https://doi.org/10.1016/​j.csr.2017.06.002.
  29. Parker, B.B. 1984. Friction Effects on the Tidal Dynamics of a Shallow Estuary. PhD thesis, The Johns Hopkins University, 311 pp.
  30. Rabinowitz, D. 1978. Dispersal properties of mangrove propagules. Biotropica 47–57, https://doi.org/​10.2307/2388105.
  31. Schmitt, K., T. Albers, T.T Pham, and S.C. Dinh. 2013. Site-specific and integrated adaptation to climate change in the coastal mangrove zone of Soc Trang Province, Viet Nam. Journal of Coastal Conservation 17(3):545–558, https://doi.org/​10.1007/s11852-013-0253-4.
  32. Sidik, F., D. Neil, and C.E. Lovelock. 2016. Effect of high sedimentation rates on surface sediment dynamics and mangrove growth in the Prong River, Indonesia. Marine Pollution Bulletin 107:355–363, https://doi.org/10.1016/j.marpolbul.2016.02.048.
  33. Swales, A., S.J. Bentley, and C.E. Lovelock. 2015. Mangrove-forest evolution in a sediment-rich estuarine system: Opportunists or agents of geomorphic change? Earth Surface Processes and Landforms 40:1,672–1,687, https://doi.org/10.1002/esp.3759.
  34. Tamura, T., K. Horaguchi, Y. Saito, V.L. Nguyen, M. Tateishi, T.K.O. Ta, F. Nanayama, and K. Watanabe. 2010. Monsoon-influenced variations in morphology and sediment of a mesotidal beach on the Mekong River delta coast. Geomorphology 116(1):11–23, https://doi.org/​10.1016/j.geomorph.2009.10.003.
  35. Thom, B.G. 1967. Mangrove ecology and deltaic geomorphology: Tabasco, Mexico. The Journal of Ecology 55:301–343, https://doi.org/​10.2307/​2257879.
  36. Tinoco, R.O., and G. Coco. 2016. A laboratory study on sediment resuspension within arrays of rigid cylinders. Advances in Water Resources 92:1–9, https://doi.org/10.1016/j.advwatres.2016.04.003.
  37. Valiela, I., J.L. Bowen, and J.K. York. 2001. Mangrove forests: One of the world’s threatened major tropical environments. Bioscience 51(10):807–815
  38. van Maanen, B., G. Coco and K.R. Bryan. 2015. On the ecogeomorphological feedbacks that control tidal channel network evolution in a sandy mangrove setting. Proceedings of the Royal Society A, https://doi.org/10.1098/rspa.2015.0115.
  39. Vo-Luong, P., and S. Massel. 2008. Energy dissipation in non-uniform mangrove forests of arbitrary depth. Journal of Marine Systems 74(1):603–622, https://doi.org/10.1016/j.jmarsys.2008.05.004.
  40. Wolanski, E. 1992. Hydrodynamics of mangrove swamps and their coastal waters. Hydrobiologia 247:141, https://doi.org/10.1007/BF00008214.
  41. Wölcke J., T. Albers, M. Roth, M. Vorlaufer, and A. Korte. 2016. Integrated Coastal Protection and Mangrove Belt Rehabilitation in the Mekong Delta. Integrated Coastal Management Programme (ICMP), Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) GmbH, Bonn, Germany, 236 pp.
  42. Yang, J.Q., H. Chung, and H.M. Nepf. 2016. The onset of transport in vegetated channels predicted by turbulent kinetic energy. Geophysical Research Letters 43:11,261–11,268, https://doi.org/​10.1002/​2016GL071092.
Copyright & Usage

This is an open access article made available under the terms of the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/), which permits use, sharing, adaptation, distribution, and reproduction in any medium or format as long as users cite the materials appropriately, provide a link to the Creative Commons license, and indicate the changes that were made to the original content. Images, animations, videos, or other third-party material used in articles are included in the Creative Commons license unless indicated otherwise in a credit line to the material. If the material is not included in the article’s Creative Commons license, users will need to obtain permission directly from the license holder to reproduce the material.