References of "Brouyère, Serge"
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See detailDownscaling transient climate change with a stochastic weather generator for the Geer catchment, Belgium
Blenkinsop, Steve; Harpham, C.; Burton, A. et al

in Climate Research (2013)

The coarse resolution of climate models creates the need for future scenarios which are downscaled to an appropriate spatial scale. Considerable effort has been devoted to the development of downscaling ... [more ▼]

The coarse resolution of climate models creates the need for future scenarios which are downscaled to an appropriate spatial scale. Considerable effort has been devoted to the development of downscaling methods but a number of important issues remain in the development of robust, usable climate scenarios. These include the incorporation of various sources of uncertainty into future scenarios and the production of scenarios at timescales relevant to planners. This paper describes a new procedure which addresses these issues by producing a multi-model ensemble of transient climate change scenarios. This method couples an existing stochastic rainfall model to a new, transient implementation of a weather generator, using changes projected by an ensemble of regional climate model (RCM) experiments. The methodology is demonstrated by the generation of transient scenarios of daily rainfall, temperature and potential evapotranspiration (PET) for the Geer catchment in Belgium for the period 2010 to 2085. The utility of these scenarios is demonstrated by assessing the changes projected by the simulated time series of several temperature indices. The Geer is projected to experience a decrease in the occurrence of frost days with a corresponding shortening of the frost season and lengthening of the growing season. By examining a large ensemble of transient scenarios the range of uncertainty in these projections is assessed, but further, it is suggested that additional information on the projected timing of specified threshold events or system responses may be provided which could aid planners in assessing the likely timescales of required interventions and adaptation responses. [less ▲]

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See detailBenzene dynamics and biodegradation in alluvial aquifers affected by river fluctuations
Batlle-Aguilar, Jordi; Morasch, Barbara; Hunkeler, Daniel et al

in Ground Water (2013)

The spatial distribution and temporal dynamics of a benzene plume in an alluvial aquifer strongly affected by river fluctuations was studied. Benzene concentrations, aquifer geochemistry datasets, past ... [more ▼]

The spatial distribution and temporal dynamics of a benzene plume in an alluvial aquifer strongly affected by river fluctuations was studied. Benzene concentrations, aquifer geochemistry datasets, past river morphology and benzene degradation rates estimated in situ using stable carbon isotope enrichment were analysed in concert with aquifer heterogeneity and river fluctuations. Geochemistry data demonstrated that benzene biodegradation was on-going under sulphate reducing conditions. Long-term monitoring of hydraulic heads and characterisation of the alluvial aquifer formed the basis of a detailed modelled image of aquifer heterogeneity. Hydraulic conductivity was found to strongly correlate with benzene degradation, indicating that low hydraulic conductivity areas are capable of sustaining benzene anaerobic biodegradation provided the electron acceptor (SO42-) does not become rate limiting. Modelling results demonstrated that the groundwater flux direction is reversed on annual basis when the river level rises up to two meters, thereby forcing the infiltration of oxygenated surface water into the aquifer. The mobilisation state of metal trace elements such as Zn, Cd and As present in the aquifer predominantly depended on the strong potential gradient within the plume. However, infiltration of oxygenated water was found to trigger a change from strongly reducing to oxic conditions near the river, causing mobilisation of previously immobile metal species and vice versa. Monitored natural attenuation appears to be an appropriate remediation strategy in this type of dynamic environment provided that aquifer characterisation and targeted monitoring of redox conditions is adequate and electron acceptors remain available until concentrations of toxic compounds reduce to acceptable levels. [less ▲]

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See detailAn object-oriented hydrogeological data model for groundwater projects
Wojda, Piotr; Brouyère, Serge ULg

in Environmental Modelling & Software (2013)

Geological and hydrogeological data are expensive to obtain in the field but are crucial for specific hydrogeological studies, from hydrogeological water balances to groundwater flow modelling and ... [more ▼]

Geological and hydrogeological data are expensive to obtain in the field but are crucial for specific hydrogeological studies, from hydrogeological water balances to groundwater flow modelling and contaminant transport, or for more integrated environmental investigations where groundwater plays a role. In this context, hydrogeological data are collected, transformed and exchanged at different scales, from local to international levels and between numerous institutions ranging from environmental consulting companies to the national and international environmental administrations. To guarantee that these exchanges are possible and meaningful, a clear structure and meta-information on applied hydrogeological data models is required. To make one step towards seamless management of groundwater projects, a new hydrogeological data model has been developed: Hg2O. It is described using object-oriented paradigms and it follows the recommendations of the International Organization for Standardization (ISO/TC211), the Open Geospatial Consortium (OGC), and the European Geospatial Information Working Group. Hydrogeological features are organized in packages of spatial feature datasets. The observations and measurements related to these features are organized in a seperate package. A particular focus is on specialized hydrogeological field experiments such as hydraulic and tracer tests. Two first implementations in the proprietary desktop ArcGIS environment and in the open-source web-based Web2GIS platform are presented, focusing on their respective standards support. [less ▲]

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See detailContribution de la tomographie et du bruit sismique à la characterisation des dépôts alluviaux dans le bassin du Kou (Burkina Faso)
Sauret, Elie ULg; Beaujean, Jean ULg; Nguyen, Frédéric ULg et al

Conference (2012, November)

Abstract The alluvial plain of the Kou basin is located in the southwest of Burkina Faso. In this basin, the main surface water resource for agricultural needs is constituted by a small perennial river ... [more ▼]

Abstract The alluvial plain of the Kou basin is located in the southwest of Burkina Faso. In this basin, the main surface water resource for agricultural needs is constituted by a small perennial river, but in recent years this resource is insufficient to satisfy the uses in agriculture. The alluvial plain which extends from either side of this river banks is expected to have the potential for constituting an alternative water supply for agricultural needs. However, the characterisation of the alluvial plain is still superficial though the plain extension and the nature of the deposits are roughly known. The objective of this study is to improve the characterisation of the alluvial plain, in particular the heterogeneity and the thickness of the deposits, using geophysical methods, namely Electrical Resistivity Tomography (ERT) and Horizontal and Vertical Spectral Ratio (H/V SR). The ERT and H/V SR methods are non invasive geophysical techniques, simple, efficient, robust and easy-to-use geophysical tools in alluvial environment based respectively on the soil resistivity and the resonant frequency of superficial materials. In upstream of the alluvial plain, near the river, these methods were used to map the sandy to sandy-thin deposits (0-5m) and the unfractured bedrock. Downstream they highlight fractured and deconsolidated bedrock drawing a V-shaped geometry of deposits. This geometry is due to the faults and the magmatic intrusions. The bottom of the V-shaped would be filled mainly by fractured/deconsolidated bedrock materials and the edges by the clay and laterites deposits. The alluvial plain would be relatively thicker downstream of the study area (approximately 30 to 50m). A correlation is obtained between ERT images and resonance frequencies determined on the H/V profiles. From a hydrogeological point of view, downstream of the study area, the alluvial plain would constitute an important aquifer with a high porosity and thick deposits. This aquifer could be easily accessible with rudimentary structures (such as sumps) and could constitute a supplementary water source, for irrigation activities in this second region of Burkina Faso. [less ▲]

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See detailDiffuse urban and industrial groundwater pollution with metallic trace elements: a comparison between affected and unaffected areas
Gesels, Julie ULg; Dollé, Fabien ULg; Leclercq, Julie et al

Poster (2012, September 20)

For metalic trace elements, spatially distributed background concentrations will be defined as a function of geological and hydrogeological context and considering the impact of diffuse pollution.

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See detailA regional flux-based risk assessment approach for multiple contaminated sites on groundwater bodies
Jamin, Pierre ULg; Dollé, Fabien ULg; Chisala, Brenda et al

in Journal of Contaminant Hydrology (2012), 127(1-4), 65-75

In the context of the Water Framework Directive (EP and CEU, 2000), management plans have to be set up to monitor and to maintain water quality in groundwater bodies in the EU. In heavily industrialized ... [more ▼]

In the context of the Water Framework Directive (EP and CEU, 2000), management plans have to be set up to monitor and to maintain water quality in groundwater bodies in the EU. In heavily industrialized and urbanized areas, the cumulative effect of multiple contaminant sources is likely and has to be evaluated. In order to propose adequate measures, the calculated risk should be based on criteria reflecting the risk of groundwater quality deterioration, in a cumulative manner and at the scale of the entire groundwater body. An integrated GIS- and flux-based risk assessment approach for groundwater bodies is described, with a regional scale indicator for evaluating the quality status of the groundwater body. It is based on the SEQ-ESO currently used in the Walloon Region of Belgium which defines, for different water uses and for a detailed list of groundwater contaminants, a set of threshold values reflecting the levels of water quality and degradation with respect to each contaminant. The methodology is illustrated with first results at a regional scale on a groundwater body-scale application to a contaminated alluvial aquifer which has been classified to be at risk of not reaching a good quality status by 2015. These first results show that contaminants resulting from old industrial activities in that area are likely to contribute significantly to the degradation of groundwater quality. However, further investigations are required on the evaluation of the actual polluting pressures before any definitive conclusion be established. [less ▲]

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See detailFlux-based Risk Assessement of the impact of Contaminants on Water resources and ECOsystems
Jamin, Pierre ULg; Dujardin, Juliette; Crèvecoeur, Sophie et al

Report (2012)

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See detailFlux-based risk assessment of the impact of contamnants on water ressources and ecosystems - FRAC-WECO.
Jamin, Pierre ULg; Dujardin, J.; Crévecoeur, Sophie et al

Report (2012)

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See detailModeling climate change impacts on groundwater resources using transient stochastic climatic scenarios
Goderniaux, Pascal ULg; Brouyère, Serge ULg; Blenkinsop, Stephen et al

in Water Resources Research (2011), 47

Several studies have highlighted the potential negative impact of climate change on groundwater reserves but additional work is required to help water managers to plan for future changes. In particular ... [more ▼]

Several studies have highlighted the potential negative impact of climate change on groundwater reserves but additional work is required to help water managers to plan for future changes. In particular, existing studies provide projections for a stationary climate representative of the end of the century, although information is demanded for the near-future. Such time-slice experiments fail to account for the transient nature of climatic changes over the century. Moreover, uncertainty linked to natural climate variability is not explicitly considered in previous studies. In this study, we substantially improve upon the state-of-the-art by using a sophisticated transient weather generator (WG) in combination with an integrated surface-subsurface hydrological model (Geer basin, Belgium) developed with the finite element modelling software 'HydroGeoSphere'. This version of the WG enables the stochastic generation of large numbers of equiprobable climatic time series, representing transient climate change, and used to assess impacts in a probabilistic way. For the Geer basin, 30 equiprobable climate change scenarios from 2010 to 2085 have been generated for each of 6 different RCMs. Results show that although the 95% confidence intervals calculated around projected groundwater levels remain large, the climate change signal becomes stronger than that of natural climate variability by 2085. Additionally, the WG ability to simulate transient climate change enabled the assessment of the likely timescale and associated uncertainty of a specific impact, providing managers with additional information when planning further investment. This methodology constitutes a real improvement in the field of groundwater projections under climate change conditions. [less ▲]

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See detailAppui à la gestion et à la protection des ressources en eaux souterraines exploitées dans la région de Bobo Dioulasso (Burkina Faso) – mise en place d’une base de données spatiales
Sauret, Elie ULg; Gardin, Nicolas; Kam, Ahmed et al

Conference (2011, November 03)

Située au sud ouest du Burkina Faso, dans la région de Bobo Dioulasso, le bassin du kou couvre 1860km2 de superficie et héberge d’énormes réservoirs en eau souterraines auxquels sont associés ... [more ▼]

Située au sud ouest du Burkina Faso, dans la région de Bobo Dioulasso, le bassin du kou couvre 1860km2 de superficie et héberge d’énormes réservoirs en eau souterraines auxquels sont associés d’importantes sources diffuses. Ces réserves en eau sont sollicitées pour l’alimentation en eau de boisson, l’industrie, l’agriculture irriguée et l’élevage ; elles ont été et demeure l’objet de nombreuses études touchant l’ingénierie de l’eau et des sols, l’imagerie satellitaire et géophysique, l’hydrochimie…. Depuis 2005, le projet de coopération bilatérale entre la WBI1 et le MAHRH-BF2 dénommé : « Appui à la gestion et à la protection des ressources en eaux souterraines exploitées dans la région de Bobo – Dioulasso » a permis de collecter, compiler et archiver des données (numériques, papiers, cartes…) qui ont servi à la construction d’une base de données spatiales couplées à un SIG (ArcGis). Des post-traitements de ces données ont permis l’établissement de cartes thématiques sur les ressources en eau de la région : carte hydrogéologique, carte de la vulnérabilité intrinsèque des aquifères souterrains, carte hydrogéomorphologique…….Utilisée au sein du projet pour les travaux de thèse en cours, la GDB des ressources en eau du bassin du Kou est largement vulgarisée et diffusée à l’échelle régionale et nationale aux utilisateurs et acteurs du domaine de l’eau. [less ▲]

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See detailAppui à la gestion et à la protection des ressources en eau souterraines exploitées dans la région de Bobo Dioulasso (Burkina Faso) - Rapport d'activité N°6 rélatif aux subventions 2010-2011
Sauret, Elie ULg; Derouane, Johan; Brouyère, Serge ULg et al

Report (2011)

L’année 2011 correspond à la troisième année de la deuxième phase d’exécution du projet de coopération bilatérale entre le Burkina Faso et Wallonie-Bruxelles International intitulé « Appui à la gestion et ... [more ▼]

L’année 2011 correspond à la troisième année de la deuxième phase d’exécution du projet de coopération bilatérale entre le Burkina Faso et Wallonie-Bruxelles International intitulé « Appui à la gestion et à la protection des ressources en eaux souterraines exploitées dans la région de Bobo-Dioulasso ». L’exécution des activités de cette troisième année s’est étalée du 01 octobre 2010 au 31 octobre 2011. L’ensemble des activités réalisées et les résultats obtenus sont repris dans ce document de synthèse. [less ▲]

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