Articles | Volume 9, issue 4
https://doi.org/10.5194/esurf-9-953-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/esurf-9-953-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| Highlight paper
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12 Aug 2021
Research article | Highlight paper |
| 12 Aug 2021
| 12 Aug 2021
Dynamics of salt intrusion in the Mekong Delta: results of field observations and integrated coastal–inland modelling
Sepehr Eslami
CORRESPONDING AUTHOR
Department of Physical Geography, Faculty of Geoscience, Utrecht University, Utrecht, 3584 CB, the Netherlands
Marine and Coastal Systems Unit, Deltares, Delft, 2629 HV, the Netherlands
Piet Hoekstra
Department of Physical Geography, Faculty of Geoscience, Utrecht University, Utrecht, 3584 CB, the Netherlands
Herman W. J. Kernkamp
Software Department, Deltares, Delft, 2629 HV, the Netherlands
Nam Nguyen Trung
Southern Institute for Water Resources Planning (SIWRP), Ho Chi Minh City, Ward 3 72710, Vietnam
Dung Do Duc
Southern Institute for Water Resources Planning (SIWRP), Ho Chi Minh City, Ward 3 72710, Vietnam
Hung Nguyen Nghia
Southern Institute of Water Resources Research (SIWRR), Ho Chi Minh City, 656 Võ Văn Ki\^{e}̣t, District 5, Vietnam
Tho Tran Quang
Southern Institute for Water Resources Planning (SIWRP), Ho Chi Minh City, Ward 3 72710, Vietnam
Arthur van Dam
Software Department, Deltares, Delft, 2629 HV, the Netherlands
Stephen E. Darby
Geography and Environment, University of Southampton, Southampton SO17 1BJ, UK
Daniel R. Parsons
Department of Geography, Environment and Earth Sciences, University of Hull, Hull HU6 7RX, UK
Grigorios Vasilopoulos
Department of Geography, Environment and Earth Sciences, University of Hull, Hull HU6 7RX, UK
Lisanne Braat
Department of Geology and Planetary Sciences, California Institute of Technology, CA 91125, USA
Maarten van der Vegt
Department of Physical Geography, Faculty of Geoscience, Utrecht University, Utrecht, 3584 CB, the Netherlands
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Melissa Wood, Ivan D. Haigh, Quan Quan Le, Hung Nghia Nguyen, Hoang Ba Tran, Stephen E. Darby, Robert Marsh, Nikolaos Skliris, Joël J.-M. Hirschi, Robert J. Nicholls, and Nadia Bloemendaal
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Earth Surf. Dynam., 11, 343–361, https://doi.org/10.5194/esurf-11-343-2023, https://doi.org/10.5194/esurf-11-343-2023, 2023
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In this study the processes leading to bank failures in the hypertidal Severn Estuary are studied employing numerical models and field observations. Results highlight that the periodic fluctuations in water levels drive an imbalance in the resisting (hydrostatic pressure) versus driving (pore water pressure) forces causing a frequent oscillation of bank stability between stable (at high tide) and unstable states (at low tide) both on semidiurnal bases and in the spring–neap transition.
Elena Bastianon, Julie A. Hope, Robert M. Dorrell, and Daniel R. Parsons
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Chengbin Zou, Paul Carling, Zetao Feng, Daniel Parsons, and Xuanmei Fan
The Cryosphere Discuss., https://doi.org/10.5194/tc-2022-119, https://doi.org/10.5194/tc-2022-119, 2022
Manuscript not accepted for further review
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Maarten G. Kleinhans, Lonneke Roelofs, Steven A. H. Weisscher, Ivar R. Lokhorst, and Lisanne Braat
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Arya P. Iwantoro, Maarten van der Vegt, and Maarten G. Kleinhans
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Alistair Hendry, Ivan D. Haigh, Robert J. Nicholls, Hugo Winter, Robert Neal, Thomas Wahl, Amélie Joly-Laugel, and Stephen E. Darby
Hydrol. Earth Syst. Sci., 23, 3117–3139, https://doi.org/10.5194/hess-23-3117-2019, https://doi.org/10.5194/hess-23-3117-2019, 2019
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Ivar R. Lokhorst, Lisanne Braat, Jasper R. F. W. Leuven, Anne W. Baar, Mijke van Oorschot, Sanja Selaković, and Maarten G. Kleinhans
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Dung Duc Tran, Gerardo van Halsema, Petra J. G. J. Hellegers, Long Phi Hoang, Tho Quang Tran, Matti Kummu, and Fulco Ludwig
Hydrol. Earth Syst. Sci., 22, 1875–1896, https://doi.org/10.5194/hess-22-1875-2018, https://doi.org/10.5194/hess-22-1875-2018, 2018
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We modeled hydrological changes under impacts of large-scale dike constructions for intensive rice production in the floodplain of the Vietnamese Mekong Delta. Four scenarios show a significant increase in peak water levels in the upstream rivers, but very few water level changes are found downstream. Water balance calculations show where the floodwater goes under four dike construction scenarios. Its impacts on the tidal areas need to be clarified in the future with a 3-D hydraulic model.
Wietse I. van de Lageweg, Stuart J. McLelland, and Daniel R. Parsons
Earth Surf. Dynam., 6, 203–215, https://doi.org/10.5194/esurf-6-203-2018, https://doi.org/10.5194/esurf-6-203-2018, 2018
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Sticky sediments are an important component of many rivers and coasts. Stickiness depends on many factors including the presence of micro-organisms, also known as biofilms. We performed a laboratory study to better understand the role of biofilms in controlling sediment transport and dynamics. We find that sand with biofilms requires significantly higher flow velocities to be mobilised compared to uncolonised sand. This will help improve predictions of sediment in response to currents and waves.
Maarten G. Kleinhans, Maarten van der Vegt, Jasper Leuven, Lisanne Braat, Henk Markies, Arjan Simmelink, Chris Roosendaal, Arjan van Eijk, Paul Vrijbergen, and Marcel van Maarseveen
Earth Surf. Dynam., 5, 731–756, https://doi.org/10.5194/esurf-5-731-2017, https://doi.org/10.5194/esurf-5-731-2017, 2017
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Creating estuaries in the laboratory has been challenging. When the ebb and flood currents are driven by ebb and flood in the sea, they are too weak to move sand. Here we describe how the periodic tilting of an entire experimental set-up leads to ebb and flood currents with similar behaviour as in nature and with enough strength to move sand. This means that this novel set-up now allows for the creation of estuarine landscapes in experiments.
Lisanne Braat, Thijs van Kessel, Jasper R. F. W. Leuven, and Maarten G. Kleinhans
Earth Surf. Dynam., 5, 617–652, https://doi.org/10.5194/esurf-5-617-2017, https://doi.org/10.5194/esurf-5-617-2017, 2017
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Mud raises concern in the short-term management of estuaries, but it is not known whether cohesive mud affects the long-term development of estuaries. We discovered that a small supply of mud from the river confines the estuary by forming stable mudflats on the sides in centuries, whereas estuaries with only sand continue to grow. Mudflats also reduce the shifting of channels and bars. This implies that changes in mud supply in estuaries may have led to changes in shape and dynamics in the past.
Jannis M. Hoch, Arjen V. Haag, Arthur van Dam, Hessel C. Winsemius, Ludovicus P. H. van Beek, and Marc F. P. Bierkens
Hydrol. Earth Syst. Sci., 21, 117–132, https://doi.org/10.5194/hess-21-117-2017, https://doi.org/10.5194/hess-21-117-2017, 2017
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Modelling inundations is pivotal to assess current and future flood hazard, and to define sound measures and policies. Yet, many models focus on the hydrologic or hydrodynamic aspect of floods only. We combined both by spatially coupling a hydrologic with a hydrodynamic model. This way we are able to balance the weaknesses of each model with the strengths of the other. We found that model coupling can indeed strongly improve discharge simulation, and see big potential in our approach.
Heiko Apel, Oriol Martínez Trepat, Nguyen Nghia Hung, Do Thi Chinh, Bruno Merz, and Nguyen Viet Dung
Nat. Hazards Earth Syst. Sci., 16, 941–961, https://doi.org/10.5194/nhess-16-941-2016, https://doi.org/10.5194/nhess-16-941-2016, 2016
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Many urban areas experience both fluvial and pluvial floods, thus this study aims to analyse fluvial and pluvial flood hazards as well as combined pluvial and fluvial flood hazards. This combined fluvial–pluvial flood hazard analysis is performed in a tropical environment for Can Tho city in the Mekong Delta. The final results are probabilistic hazard maps, showing the maximum inundation caused by floods of different magnitudes along with an uncertainty estimation.
W. A. Marra, S. J. McLelland, D. R. Parsons, B. J. Murphy, E. Hauber, and M. G. Kleinhans
Earth Surf. Dynam., 3, 389–408, https://doi.org/10.5194/esurf-3-389-2015, https://doi.org/10.5194/esurf-3-389-2015, 2015
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Groundwater seepage creates valleys with typical theater-shaped valley heads, which are found on Earth and on Mars. For a better interpretation of these systems, we conducted scale experiments on the formation such valleys. We find that entire landscapes, instead of just the shape of the valleys, provide insights into the source of groundwater. Landscapes filled with valleys indicate a local groundwater source in contrast to sparsely dissected landscapes formed by a distal source of groundwater.
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Short summary
Increased salt intrusion jeopardizes freshwater supply to the Mekong Delta, and the current trends are often inaccurately associated with sea level rise. Using observations and models, we show that salinity is highly sensitive to ocean surge, tides, water demand, and upstream discharge. We show that anthropogenic riverbed incision has significantly amplified salt intrusion, exemplifying the importance of preserving sediment budget and riverbed levels to protect deltas against salt intrusion.
Increased salt intrusion jeopardizes freshwater supply to the Mekong Delta, and the current...
