Influence of climate change on a Ghijben–Herzberg lens

Maas, Kees

doi:10.1016/j.jhydrol.2007.09.020

Cited by 45 publications

(53 citation statements)

References 4 publications

(4 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Under certain conditions the rainwater lens may become so small, or even disappear, that saline groundwater may reach the root zone via capillary rise, affecting crop growth (Steppuhn et al, 2005;Katerji et al, 2003;Flowers, 2004;Rozema and Flowers, 2008) and natural vegetation (Jolly et al, 2008;Antonellini and Mollema, 2009). Shallow rainwater lenses in areas with saline seepage are very vulnerable to climate change (changing precipitation surpluses) and to a rising sea level (enhancing seepage) as shown by Maas (2007).…”

Section: Introductionmentioning

confidence: 99%

“…Some analytical and numerical steady-state approaches to modelling rainwater lenses under conditions of upward groundwater seepage have been described (Schot et al, 2004;Maas, 2007;Eeman et al, 2011). Eeman et al (2011) investigated the parameter groups that dominate the mixing processes for physically feasible ranges of parameters, using the analytical approach by Maas (2007) and the numerical transport code SUTRA (Voss and Provost, 2008).…”

Section: Introductionmentioning

confidence: 99%

“…Eeman et al (2011) investigated the parameter groups that dominate the mixing processes for physically feasible ranges of parameters, using the analytical approach by Maas (2007) and the numerical transport code SUTRA (Voss and Provost, 2008). Schot et al (2004) used a numerical model to simulate the development of rainwater lenses in fens under fresh groundwater seepage conditions.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Shallow rainwater lenses in deltaic areas with saline seepage

Louw

Eeman

Siemon

et al. 2011

Hydrol. Earth Syst. Sci.

View full text Add to dashboard Cite

Abstract. In deltaic areas with saline seepage, freshwater availability is often limited to shallow rainwater lenses lying on top of saline groundwater. Here we describe the characteristics and spatial variability of such lenses in areas with saline seepage and the mechanisms that control their occurrence and size. Our findings are based on different types of field measurements and detailed numerical groundwater models applied in the south-western delta of the Netherlands. By combining the applied techniques we could extrapolate measurements at point scale (groundwater sampling, temperature and electrical soil conductivity (TEC)-probe measurements, electrical cone penetration tests (ECPT)) to field scale (continuous vertical electrical soundings (CVES), electromagnetic survey with EM31), and even to regional scale using helicopter-borne electromagnetic measurements (HEM). The measurements show a gradual mixing zone between infiltrating fresh rainwater and upward flowing saline groundwater. The mixing zone is best characterized by the depth of the centre of the mixing zone D mix , where the salinity is half that of seepage water, and the bottom of the mixing zone B mix , with a salinity equal to that of the seepage water (Cl-conc. 10 to 16 g l −1 ). D mix is found at very shallow depth in the confining top layer, on average at 1.7 m below ground level (b.g.l.), while B mix lies about 2.5 m b.g.l. The model results show that the constantly alternating upward and downward flow at low velocities in the confining layer is the main mechanism of mixing between rainwater and saline seepage and determines the position and extent of the mixing zone (D mix and B mix ). Recharge, seepage flux, and drainage depth are the controlling factors.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Shallow rainwater lenses in deltaic areas with saline seepage

Louw

Eeman

Siemon

et al. 2011

Hydrol. Earth Syst. Sci.

View full text Add to dashboard Cite

show abstract

“…the outflow zone at the dunes' perifery, or whether or not the salt underlying water is flowing, assuming a sharp fresh/salt interface (Badon-Ghijben 1888;Herzberg 1901;Van Der Veer 1977;Maas 2007). Investigating fresh water lenses in low-lying flat coastal regions, revealed that the analytical solution provided by Maas (2007) is in close agreement with their numerical modelling using the model SUTRA-3D.…”

Section: Fresh Water Lens Persistencementioning

confidence: 72%

Fresh Water Lens Persistence and Root Zone Salinization Hazard Under Temperate Climate

Stofberg

Essink

Pauw

et al. 2016

Water Resour Manage

View full text Add to dashboard Cite

In low lying deltaic areas in temperate climates, groundwater can be brackish to saline at shallow depth, even with a yearly rainfall excess. For primary production in horticulture, agriculture, and terrestrial nature areas, the fresh water availability may be restricted to so-called fresh water lenses: relatively thin pockets of fresh groundwater floating on top of saline groundwater. The persistence of such fresh water lenses, as well as the quantity and quality of surface water is expected to be under pressure due to climate change, as summer droughts may intensify in North-West Europe. Better understanding through modelling of these fresh water resources may help anticipate the impact of salinity on primary production. We use a simple model to determine in which circumstances fresh water lenses may disappear during summer droughts, as that could give rise to enhanced root zone salinity. With a more involved combination of expert judgement and numerical simulations, it is possible to give an appraisal of the hazard that fresh water lenses disappear for the Dutch coastal regions. For such situations, we derive an analytical tool for anticipating the resulting salinization of the root zone, which agrees well with numerical simulations. The provided tools give a basis to quantify which lenses are in hazard of disappearing periodically, as well as an impression in which coastal areas this hazard is largest. Accordingly, these results and the followed procedure may assist water management decisions and prioritization strategies leading to a secure/ robust fresh water supply on a national to regional scale.

show abstract

“…Stuyfzand 1993;Vandenbohede et al 2008;Röper et al 2012). In low-lying areas, with a soil surface close to mean sea level (MSL), thin lenses are found, on top of upward seeping saline groundwater (Maas 2007;Eeman et al 2011;De Louw et al 2011). Also in the absence of saline groundwater, lenses can be formed on deeper, upwelling groundwater and differ from that groundwater by its chemical signature, which can be ecologically relevant (Cirkel et al 2014).…”

Section: Introductionmentioning

confidence: 99%

Cation exchange in a temporally fluctuating thin freshwater lens on top of saline groundwater

2016

View full text Add to dashboard Cite

In coastal-zone fields with a high groundwater level and sufficient rainfall, freshwater lenses are formed on top of saline or brackish groundwater. The fresh and the saline water meet at shallow depth, where a transition zone is found. This study investigates the mixing zone that is characterized by this salinity change, as well as by cation exchange processes, and which is forced by seepage and by rainfall which varies as a function of time. The processes are first investigated for a onedimensional (1D) stream tube perpendicular to the interface concerning salt and major cation composition changes. The complex sequence of changes is explained with basic cation exchange theory. It is also possible to show that the sequence of changes is maintained when a two-dimensional field is considered where the upward saline seepage flows to drains. This illustrates that for cation exchange, the horizontal component (dominant for flow of water) has a small impact on the chemical changes in the vertical direction. The flow's horizontal orientation, parallel to the interface, leads to changes in concentration that are insignificant compared with those that are found perpendicular to the interface, and are accounted for in the 1D flow tube. Near the drains, differences with the 1D considerations are visible, especially in the longer term, exceeding 100 years. The simulations are compared with field data from the Netherlands which reveal similar patterns.

show abstract

Influence of climate change on a Ghijben–Herzberg lens

Cited by 45 publications

References 4 publications

Shallow rainwater lenses in deltaic areas with saline seepage

Shallow rainwater lenses in deltaic areas with saline seepage

Fresh Water Lens Persistence and Root Zone Salinization Hazard Under Temperate Climate

Cation exchange in a temporally fluctuating thin freshwater lens on top of saline groundwater

Contact Info

Product

Resources

About