Publications of Eric Hallot
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See detailMicrohabitats survey used in river restoration
Peeters, Alexandre ULiege; Hallot, Eric ULiege; Houbrechts, Geoffrey ULiege et al

Conference (2011, October 14)

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See detailRestauration hydromorphologique : Les échelles de travail optimales ?
Hallot, Eric ULiege; Peeters, Alexandre ULiege; Verniers, Gisèle et al

Conference (2011, October 03)

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See detailFacteurs de variabilité spatiale des caractéristiques des débits minimums annuels des rivières wallonnes (Belgique)
Vadnais, Marie-Ève; Assani, Ali A.; Hallot, Eric ULiege et al

in Revue des Sciences de l'Eau (2011), 24(3), 311-327

The goal of this study was to determine which environmental factors affect the spatial variability of annual minimum streamflow characteristics for 34 rivers in Wallonia (Belgium) using two complementary ... [more ▼]

The goal of this study was to determine which environmental factors affect the spatial variability of annual minimum streamflow characteristics for 34 rivers in Wallonia (Belgium) using two complementary methods: theascending hierarchical classification method and the linear correlation method. Both methods were applied after principal component analysis transformation was applied to the data. The ascending hierarchical classification method (Ward’s method) identified the effect of lithology and anthropogenic activity (groundwater pumping) on the fundamental characteristics of annual minimum flows. Rivers that drain a relatively permeable substrate are characterized by very high flow volumes with low interannual variability, high interannual variability of the period of occurrence, and small asymmetry coefficients. Rivers that drain low permeability or impermeable substrates show the opposite patterns. Rivers in which flow is subjected to artificial influences are characterized by greater variability of the magnitude and of the period of occurrence of annual minimum flows than natural rivers. Analysis of linear correlations between streamflow characteristics and environmental factors highlighted a correlation between the form of the distribution curves of annual minimum flows and several environmental factors (climate, land use, location and physiographic characteristics of the watersheds). [less ▲]

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See detailÉtude cartographique et projet de restauration sur une rivière rectifiée, l’Eau Blanche
Peeters, Alexandre ULiege; Verniers, Gisèle; Hallot, Eric ULiege et al

Conference (2010, October 04)

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See detailWALPHY : un projet pilote de réhabilitation de cours d’eau
Verniers, Gisèle; Peeters, Alexandre ULiege; Hallot, Eric ULiege et al

Conference (2010, September 20)

Grâce au co-financement de l’Union européenne dans le cadre de la ligne budgétaire LIFE Environnement, un projet pilote sur la restauration physique des cours d’eau a démarré en janvier 2009 pour une ... [more ▼]

Grâce au co-financement de l’Union européenne dans le cadre de la ligne budgétaire LIFE Environnement, un projet pilote sur la restauration physique des cours d’eau a démarré en janvier 2009 pour une durée de 5 ans. Son nom : WALPHY pour « Wallonie – physique ». Le projet est coordonné par la Direction des Cours d’Eau Non Navigables DCENN (Service Public de Wallonie SPW - Belgique) dont le district de Namur assure la réalisation des travaux de restauration. Deux partenaires scientifiques assument l’évaluation et le suivi de ces travaux : le Laboratoire d’Hydrographie et de Géomorphologie Fluviatile de l’Université de Liège et l’Unité de Recherche en Biologie des Organismes des Facultés Universitaires de Namur. [less ▲]

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See detailDesign of a decision tool for hydromorphological restoration of water bodies in Walloon Region
Peeters, Alexandre ULiege; Hallot, Eric ULiege; Verniers, Gisèle et al

Poster (2010, May 05)

The pilot project WALPHY (LIFE + Environment LIFE07 ENV/B/000038, UE-funded) develops a structured approach aiming at improving hydromorphological quality of the upstream Meuse basin in order to achieve ... [more ▼]

The pilot project WALPHY (LIFE + Environment LIFE07 ENV/B/000038, UE-funded) develops a structured approach aiming at improving hydromorphological quality of the upstream Meuse basin in order to achieve the “good ecological status” required by the Water Framework Directive (WFD 2000/60). It began in January 2009 for a period of 5 years. River’s biological recovery needs the recovery of river’s structure and physical dynamics. Returning to "good ecological status" inevitably involves physical restoration of affected rivers. Physical component of aquatic environment acts as a limiting factor for their functioning. Three types of modification are key obstacles for river good ecological status: (i) fluxes alteration (discharge, sedimentation. . . ), (ii) forms alteration (uniform facies. . . ) and (iii) biotopes access alteration (lateral connections breaks, modification of the continuity upstream/ downstream. . . ). Therefore hydromorphology is needed to implement the WFD. To respond to this legal necessity, we develop a unique, useful and suitable methodology in Walloon Region to determine and schedule river physical quality restoration works. This methodology has been applied on 3 “risk water bodies”. The works are based on two axes : longitudinal continuity and transversal continuity. The two first selected water bodies (Bocq river, eastern tributary of the Meuse) seem to be convenient for the restoration works which concern the longitudinal continuity due to the presence of dams and other obstacles usually between 1 and 3 m high. These works consist in dam management (weir removal or fish passage) taking into account hydromorphological (bedload transport) and biological (invertebrate or fish species free movement) impacts. The third water bodies (Eau Blanche river, western tributary of the Meuse) presents straightened rivers with artificial banks, witch consequently own bad connections between the stream and its floodplain. This water bodies should therefore be appropriated for the works based on the transversal continuity recovery. They consist in enhancing straightened river channels, restoring meanders or bank restoration. The first river restoration works will take place from summer 2010. A monitoring has already been undertaken to draw up the situation before the restoration works, witch will be able to compare to the situations during and after works. In addition, a natural site has been chosen to enable any comparison with the intervention sites. The geomorphological monitoring is based on physical and sedimentological parameters (substrate cartography, velocity measures, stream channel DEM, topography and sedimentological index). The ecological monitoring consists in analysing the physical and chemical parameters (turbidity, suspended sediment load). It also analyses the biological quality through 3 indicators: macrophytes, macroinvertebrates and fishes. Among other, a microhabitats method has been improved and applied on 3 intervention sites and 1 natural site. The microhabitats cartography results from both the flow velocity cartography and the substrate cartography. With this method, the physical quality of each intervention site could be compared with the natural site and above all with the future situation. Our method is also useful to inventory precisely invertebrates and to characterise fish habitats. [less ▲]

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See detailUnit stream power as a base for regional river typology
Hallot, Eric ULiege; Houbrechts, Geoffrey ULiege; Levecq, Yannick et al

Poster (2010)

In order to assess the hydromorphological quality of surface waters, stakeholders need river typologies accurate and functional enough to be a really efficient management tool. From a typological study ... [more ▼]

In order to assess the hydromorphological quality of surface waters, stakeholders need river typologies accurate and functional enough to be a really efficient management tool. From a typological study based a broad set of hydromorphological field data, we have shown that some variables, like the unit stream power (), are particularly appropriate to describe the dynamics of a river. Initial results of repeated measurement in more than 80 sites revealed a regional differentiation based on critical values of stream power at bankfull discharge. The aim of this study is to present a unit stream power mapping for the whole network based on general equation  =  g Q S / w, with  the density of water, g the acceleration due to gravity, Q the discharge, S the slope and w the channel width). Slope is extracted from DEM. Bankfull discharge and width estimations are furnished by allometric equations using the watershed area. Different coefficients are used according to regional differentiations based on bedload size and watershed permeability. The statistical significance of all equations was tested by covariance analysis. A correction taking into account the used log-log scale, was also applied to the obtained allometric equations (Fergusson, 1988). Using a 30 x 30 meters DEM, GIS routines were developed. A first one automatically sectorizes the network and a second evaluates the unit streamspower in each location. We propose a 7-level classification in accordance with the associated morphological processes describe in the literature (from fixed meanders to step-pools system). The mapping unit starts at the Strahler second order. Our results not only support a regional typology, but moreover allow us to describe natural regions in function of river dynamics and to estimate the resistance of restoration works like vegetal techniques. It can also provide estimates of the excess stream power (the fraction of the actual stream power exceeding the power at which bedload particles start to move). (Fergusson, R.,I., 1988. River loads underestimated by rating curves, Water Resour. Res., 24(7), 1217–1219.) [less ▲]

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See detailArtificially generating sediment incipient motion in natural conditions
Gob, Frédéric ULiege; Houbrechts, Geoffrey ULiege; Linares Carreté, Alba et al

Poster (2010)

Incipient motion thresholds for gravel bed rivers are studied in flumes and natural rivers. Flume studies allow variables such as channel slope, water velocity, water depth, sediment size and sediment ... [more ▼]

Incipient motion thresholds for gravel bed rivers are studied in flumes and natural rivers. Flume studies allow variables such as channel slope, water velocity, water depth, sediment size and sediment composition to be controlled. Meanwhile, in the field, the incipient motion of particles is studied in natural conditions allowing the structure of the bed and the flood characteristics to be considered. Though much less developed, an intermediate possibility also exists. By artificially accelerating near bottom velocity of the water flow in a small portion of the bed, it is possible to initiate sediment transport. This allows sediment incipient motion to be observed in natural conditions while controlling the water velocities. The Cemagref (HHLY) has developed a device which confines water flow in a small tunnel on the bottom of the riverbed. It was developed in order to create a boundary layer similar to the one generated by natural flow. Water is injected into a filter which smoothes the flow before it enters a Plexiglas tunnel where sediment motion is observed. The flow is accelerated by two large pumps that allow flow velocities of up to 2.5 m/s in a small area 40 cm long, 20 cm wide and 12 cm high. As the water flow is confined, large scale turbulence similar to that occurring in natural rivers cannot be reproduced using the device. The velocity profile in the tunnel is stable and in equilibrium with the riverbed. Sediment motion was observed using this device on three Belgian gravel bed rivers (3.5 cm <D50<8 cm). The incipient critical velocities measured were coherent in the three rivers sampled, ranging between 1.3 m/s and 1.7 m/s. A progressive increase in velocity in the tunnel permitted size selective entrainment to be observed. Analysis of the particle entrainment schemes and associated velocities allowed the role played by the armoured layer and the Di/D50 ratio to be more fully understood. Critical velocities measured using the device were also compared to critical velocities observed in natural conditions, determined during several pebble tracing campaigns. This revealed that incipient motion velocities of the largest particles recorded in artificial conditions were systematically larger than those observed in natural conditions. This demonstrates the roles played by large scale turbulence and the vertical component of the flow velocity in single particle entrainment. Due to its inherent characteristics, both of these flow components are weak in the artificial conditions generated by the device. In conclusion, our study demonstrates that this type of device is a useful tool in observing and studying incipient motion processes and, in particular, the role played by the bed structure (armouring, protrusion, etc.). However, some improvements are still required in order to more accurately measure critical velocities, allowing critical discharges to be determined. [less ▲]

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See detailStudy of the bedload transport in gravel bed rivers
Houbrechts, Geoffrey ULiege; Hallot, Eric ULiege; Peeters, Alexandre ULiege et al

Conference (2009, July)

Bedload transport has been studied in Ardenne rivers using different methods. Experiments with marked pebbles were carried out on gravel bed rivers in order to determine critical parameters of ... [more ▼]

Bedload transport has been studied in Ardenne rivers using different methods. Experiments with marked pebbles were carried out on gravel bed rivers in order to determine critical parameters of mobilisation. The tracking of more than 1000 elements marked with PIT-tags (Passive Integrated Transponder) has been performed on different sized rivers during three hydrological seasons. These surveys allowed us to determine the initial motion of bed material, to measure the distance of particle travel from flood to flood, to reconstruct the trajectories of pebbles, to analyze the burying of particles into the subsurface layer and to identify the trapping sites and their effects on the bedload progression. On the same rivers, the thickness of the active bed layer has been measured using scour chains. It appears that the mobilised layer thickness increases with specific stream power. Bedload discharge of several floods has also been estimated crossing the active layer thickness and the mean progression distance of marked pebbles. Pits have been dug across the bed of a gravel bed stream (catchment area of 12 km²) in order to trap all particles moving on the bed. Volume of sediments trapped has been measured after each flood event and the largest elements mobilised have been measured. These observations show that bedload trapped is clearly more important that bedload discharge estimated by the method of scour chains and marked pebbles. This difference is for the most part explained by the trapping of sandy matrix from the subsurface layer, which is also moving on the bed. In this headwater stream (forested floodplain), the specific bedload discharge is only 0.4 t.km-1.year-1. Such a value is relatively low in comparison with other Ardenne rivers (up to 2,5 t.km-1.year-1), but may be partly explained by numerous vegetation logjams, which slow down bedload progression and increase bed roughness. [less ▲]

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See detailShape and amount of the Quaternary uplift of the western Rhenish shield and the Ardennes (western Europe)
Demoulin, Alain ULiege; Hallot, Eric ULiege

in Tectonophysics (2009), 474

A good evaluation of the Quaternary uplift of the Rhenish shield is a key element for the understanding of the Cenozoic geodynamics of the western European platform in front of the alpine arc. Previous ... [more ▼]

A good evaluation of the Quaternary uplift of the Rhenish shield is a key element for the understanding of the Cenozoic geodynamics of the western European platform in front of the alpine arc. Previous maps of the massif uplift relied on fluvial incision data since the time of the rivers' Younger Main Terrace to infer a maximum post-0.73 Ma uplift of ~290 m in the SE Eifel. Here, we propose a new interpretation of the incision data of the intra-massif streams, where anomalies in the terrace profiles would result from knickpoint retreat in the tributaries of the main rivers rather than from tectonic deformation. We also use additional geomorphological data referring to (1) deformed Tertiary planation surfaces, (2) the history of stream piracy that severely affected the Meuse basin in the last 1 Ma, and (3) incision data outside the Rhenish shield. A new map of the post-0.73 Ma uplift of the Rhenish shield is drawn on the basis of this enlarged dataset. It reduces the maximum amount of tectonic uplift in the SE Eifel to ~140 m and modifies the general shape of the uplift, namely straightening its E–W profile. It is also suggested that an uplift wave migrated across the massif, starting from its southern margin in the early Pleistocene and currently showing the highest intensity of uplift in the northern Ardennes and Eifel. These features seem to favour an uplift mechanism chiefly related to lithospheric folding and minimize the impact on the topography of a more local Eifel plume. [less ▲]

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See detailAmount and controls of the Quaternary denudation in the Ardennes massif (western Europe)
Demoulin, Alain ULiege; Hallot, Eric ULiege; Rixhon, Gilles ULiege

in Earth Surface Processes and Landforms (2009), 34

It is still debated whether the primary control on the middle Pleistocene denudation of the uplifted Ardennes massif (western Europe) is tectonic or climatic. Here, based on geomorphological observations ... [more ▼]

It is still debated whether the primary control on the middle Pleistocene denudation of the uplifted Ardennes massif (western Europe) is tectonic or climatic. Here, based on geomorphological observations, we calculate the amount of river incision and interfluve denudation in the Meuse basin upstream of Maastricht since 0·7 Ma and we show that the main response to tectonic forcing was incision. This allows us to provide first-order estimates of the tectonic and climatic contributions to the denudation of the Ardennes. From a dataset of 71 remnants of a terrace level dated ~0·7 Ma, we first derive a basin-scale functional relationship linking incision with distances to the regional base level (Lc) and to the source (Ls) in the Ourthe basin (pertaining to the Ardennian part of the Meuse basin). Expressed as I = I0*(1 – a*Lcb/Lsc), I0 being the incision measured at the basin outlet, this relationship calculates that river incision has removed 84 km3 of rock in the Meuse basin upstream of Maastricht since 0·7 Ma. In the same time, 292 km3 were eroded from the interfluves. A comparison of these volumes shows that the tectonically forced river incision accounts for ~22% of the total post-0·7 Ma denudation. Furthermore, the mean denudation rate corresponding to our geomorphological estimate of the overall denudation in the Meuse basin since 0·7 Ma amounts to 27 mm/ky, a figure significantly lower than the ~40 mm/ky mean rate derived from 10Be studies of terrace deposits of the Meuse (Schaller et al., 2004). This suggests that, taken as a basin average, the 10Be-derived rate is overestimated, probably due to an overrepresentation of the erosion products of the rapidly incising valleys in the alluvial deposits. [less ▲]

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See detailAnalysis of lateral mobility of channels at different spatial and time scales (Ardenne massif, Belgium)
Houbrechts, Geoffrey ULiege; Van Campenhout, Jean ULiege; Hallot, Eric ULiege et al

Poster (2009)

Lateral mobility of Ardenne rivers has been studied at different scales using three complementary methods. We firstly compared the layout of channels on topographic maps (since the 18th century) and ... [more ▼]

Lateral mobility of Ardenne rivers has been studied at different scales using three complementary methods. We firstly compared the layout of channels on topographic maps (since the 18th century) and aerial pictures. Given that these documents have different scales and projection systems, they were transformed into a common referencing system. This method allowed us to study the lateral shifting of channels, however, as the mobility of Ardenne rivers is relatively low, the errors of geometric rectifications are often more important than lateral displacements. Therefore, to visualize these deformations, georeferenced documents were overlaid with a regular grid of points. We represented the imprecision vector based on x and y residual components for each point. These vectors show the direction of the deformation and its amplitude. Large quantities of iron slag are present in the sediments of Ardenne rivers. These waste products come from hundreds of ironworks built close to rivers since the 14th century. Analyses of slag concentrations in alluvial deposits allowed us to delimitate the sectors of floodplains eroded by rivers during the last centuries. In these sectors, slag elements are present at the contact with the gravel sheet. Finally, we analysed the topography of floodplains from a DEM-LIDAR. This digital elevation model has been established by the Walloon Region for the cartography of flood risk in floodplains. It presents a Z mean error of only 15 cm and a X-Y resolution of 1 m. In order to reveal paleochannels and topographic alluvial units, we subtracted a surface, corresponding to the longitudinal water surface slope, extracted from the DEM. By using this method, we are able to obtain the relative height of any point of the floodplain with regard to the water surface, projected perpendicularly to the layout, on this point. This procedure reveals paleochannels even if they are almost infilled and allows us to delimitate, for several kilometres, alluvial units, which have been formed at different periods. [less ▲]

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See detailHabitat Choice by Atlantic Salmon Parr in Relation to Turbulence at a Reach Scale
Enders, Eva C; Roy, Mathieu L; Ovidio, Michaël ULiege et al

in North American Journal of Fisheries Management (2009), 29(6), 1819-1830

The variables commonly used to describe the physical habitat of Atlantic salmon Salmo salar parr are average velocity, water depth, and substrate. A variety of micro- and mesohabitat models have been ... [more ▼]

The variables commonly used to describe the physical habitat of Atlantic salmon Salmo salar parr are average velocity, water depth, and substrate. A variety of micro- and mesohabitat models have been developed using these variables to assess habitat quality. However, Atlantic salmon parr live in highly turbulent streams and rivers in which intense fluctuations of water velocity occur. Laboratory experiments have shown that turbulence affects the behavior and energetics of fish. Nevertheless, habitat use in relation to the strong temporal variability of velocity in natural environments has rarely been studied. In this study, Atlantic salmon parr habitat was examined in relation to turbulence in the Patapedia River, Quebec. Rather than taking the usual approach of surveying a large population at one point in time, we used an intensive radiotelemetry tracking survey that focused on the habitat use of a few individual fish over an extended period. We analyzed habitat use in relation to several dynamic hydraulic variables. Our results revealed that under naturally turbulent conditions, the parr displayed high individual variability in their habitat use. Such heterogeneous use of habitat suggests that individuals are not constrained to a single habitat type. Furthermore, no differences were observed in habitat use among the four daily periods (dawn, day, dusk, and night) for individual parr. [less ▲]

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See detailCan turbulence statistics reflect the meso-habitat choice of juvenile salmonids
Enders, Eva; Ovidio, Michaël ULiege; Hallot, Eric ULiege et al

in Proceedings of the combined conference on Hydro-Informatics and Ecohydraulics, Concepcion, Chile, January 2009. (2009)

Variables commonly used to describe the physical habitat of Atlantic salmon Salmo salar L. parr are average velocity, water depth, and substrate. A variety of micro- and meso-habitat models have been ... [more ▼]

Variables commonly used to describe the physical habitat of Atlantic salmon Salmo salar L. parr are average velocity, water depth, and substrate. A variety of micro- and meso-habitat models have been developed using these variables to assess habitat quality. However, Atlantic salmon parr live in highly turbulent streams and rivers, in which intense fluctuations of water velocity occur. Laboratory experiments have shown that turbulence affects the behavior and energetics of fish. Nevertheless, habitat use in relation to the strong temporal variability of velocity in natural environments has rarely been studied. In this study, Atlantic salmon parr habitat was examined in relation to turbulence in the Patapédia River, Québec, Canada. We analyzed meso-habitat use in relation to several dynamic hydraulic variables. Our results revealed that in a natural turbulent condition, parr displayed high individual variability in habitat use in relation to turbulence. Such heterogeneous use of habitat suggests that individuals are not constrained to a single habitat type but that they have a tendency to use areas with lower turbulence. [less ▲]

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See detailEtude géomorphologique des barrages de travertin du Hoyoux
Franco, Bruno ULiege; Houbrechts, Geoffrey ULiege; Van Campenhout, Jean ULiege et al

in Bulletin de la Société Géographique de Liège (2008)

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See detailLa typologie et les caractéristiques hydromorphologiques des cours d'eau wallons
Petit, François ULiege; Hallot, Eric ULiege; Houbrechts, Geoffrey ULiege et al

in Bilan d'une décennie d'ingénierie écologique (2008)

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See detailTechniques de marquage de la charge de fond des rivières
Hallot, Eric ULiege; Houbrechts, Geoffrey ULiege; Mols, Julien et al

Poster (2007, October)

Durant près d’une décennie, nous avons analysé le transport de la charge de fond dans une gamme de rivières de taille différente et situées dans des contextes géomorphologiques variés, au sein du massif ... [more ▼]

Durant près d’une décennie, nous avons analysé le transport de la charge de fond dans une gamme de rivières de taille différente et situées dans des contextes géomorphologiques variés, au sein du massif ardennais. Pour ce faire, des techniques de marquages traditionnels ont été mises en oeuvre (marquage de placette à la peinture, injection de galets peints) et des méthodes innovantes ont également été testées et développées (galets équipés d’émetteur radio, de pit-tag ou d’une charge métallique). Chacune de ces méthodes permet de déterminer certains aspects du transport de la charge de fond (paramètres de mobilisation, distance de charriage, compétence, échanges verticaux dans la couche active, tri hydraulique). Le type de marquage utilisé doit également être adapté aux caractéristiques intrinsèques de la rivière (pente, largeur, débit, espacement seuil mouille), de la charge de fond (granularité des sédiments, épaisseur de la couche active), de la disponibilité en matériaux et de l’héritage géomorphologique. Une étude systématique des taux de récupération des galets, des temps de mise en oeuvre, de la représentativité des résultats nous permet de présenter une première synthèse méthodologique détaillant les avantages et les inconvénients des différentes techniques en fonction du résultat escompté et du type de rivière. [less ▲]

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See detailEvaluation de la résistance des aménagements par techniques végétales face aux événements hydrologiques
Peeters, Alexandre ULiege; Hallot, Eric ULiege; Houbrechts, Geoffrey ULiege et al

Poster (2007, October)

Lors du suivi géomorphologique d’aménagement ou de restauration de cours d’eau par techniques végétales réalisé en Région Wallonne, nous nous sommes entre autres intéressés à la résistance que ces ... [more ▼]

Lors du suivi géomorphologique d’aménagement ou de restauration de cours d’eau par techniques végétales réalisé en Région Wallonne, nous nous sommes entre autres intéressés à la résistance que ces techniques offraient face aux différents évènements hydrologiques. Nous avons étudié plusieurs types de techniques (telles que plantations, caissons, épis, peignes et fascines, végétalisation de gabions, techniques combinées...) réalisés sur des rivières de différentes tailles, situées dans des contextes géomorphologiques régionaux variés (impliquant une dynamique différente). La résistance de ces techniques a été évaluée en utilisant la puissance spécifique calculée lors des différentes crues subies par l’aménagement. Cette dernière représente la capacité de travail qu'une rivière peut effectuer et elle permet, ente autres, d'appréhender l'activité des rivières en ce qui concerne les formes et la dynamique des méandres (Ferguson, 1981 ; Bravard, 1991) mais également la possibilité de réaction et d'adaptation des rivières en réponse à des travaux d'aménagement (Brookes, 1998). Les puissances spécifiques ont été calculées non seulement pour le débit à plein bord mais aussi pour la première crue importante survenue après la mise en place du chantier. Par ailleurs, les récurrences des crues ont également été déterminées. Ces premiers résultats nous permettent de proposer une synthèse s’intégrant dans un guide technique (Technique végétales : conception, application et recommandations, GIREA - LHGF) destinés aux différents gestionnaires. BRAVARD J.P., 1991. La dynamique fluviale à l’épreuve des changements environnementaux : Quels enseignements applicables à l’aménagement des rivières ? La Houille Blanche, 7-8, 515-521. BROOKES A., 1988. Channelized rivers, perspectives for environmental management. Wiley, New York, 326 p. FERGUSON R.I., 1981. Channel form and channel changes ; In British Rivers, Lewin J. (Ed), Allen, London,, 91- 125. [less ▲]

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See detailBehavioural tactics and spawning activity of rheophilic cyprinids radio-tracked in the transition zone between natural flow and minimum flow conditions
Ovidio, Michaël ULiege; Guillaume, Nicolas; Hallot, Eric ULiege et al

Conference (2007, June)

Using water resources for hydro-electricity production influences and limits the quality and quantity of habitat available for use by resident fishes. Changes in the fish community structure after setting ... [more ▼]

Using water resources for hydro-electricity production influences and limits the quality and quantity of habitat available for use by resident fishes. Changes in the fish community structure after setting minimum flow conditions have been more frequently studied than the behavioural adaptations of fish living in the vicinity of the disturbed river section. In the River Amblève (River Meuse basin, Belgium), a hydraulic power plant bypasses the river over a length of 10 km. Adult nase Chondrostoma nasus (n=10) and barbel Barbus barbus (n=8) were captured in the restitution zone of the turbinated flow several weeks before their reproduction periods. They were equipped with implant radio transmitters and manually and intensively tracked over several months to more than 1 year. The environmental conditions (water temperature and flow) as well as the geomorphology of the river were compared in both natural and flow-regulated sections. Nase and barbel demonstrated the capacity to map their contrasted environment and adapted their space and habitat utilisation as well as the choice of their spawning sites in relation with their specific biological characteristics and the environmental variations. The results are discussed in the context of the management of fish movements in flow-regulated rivers. [less ▲]

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