Vincent Viel - Academia.edu (original) (raw)

Papers by Vincent Viel

Research paper thumbnail of Systemic analysis of sediment connectivity in the Wadi Leben watershed, Tunisia (Mediterranean): Between morpho-structural potentialities, originality of the hydrographic network and societal reorganizations

<p>The Kneiss Islands and the outlet of the Wadi Leben watershed (Tunisia), is an i... more <p>The Kneiss Islands and the outlet of the Wadi Leben watershed (Tunisia), is an internationally recognized site, classified ZICO (1990) and Ramsar (2007) for the high fish productivity of its shallow waters, which makes these areas a favorable breeding ground for migratory birds. The difficulties to access to the sea make these areas slightly degraded. However, the sustainability of this site is now being jeopardized with anthropogenic pressure becoming progressively stronger on this littoral zone and the upstream watershed.</p><p>Our objective is to show the original hydro-sedimentary functioning of this Mediterranean watershed, shared between physical characteristics and intrusive agricultural practices in full reconversion (from local/traditional to international/globalized): (i) The upstream zone of the watershed is subject to sediment retention related to the implementation of a hydro-agricultural and anti-erosion system (water and soil conservation works); (ii) The intermediate zone, by its morpho-structural and sedimentogenetic characteristics, has favored the accumulation of sediments in the valley bottoms, which makes it not only a transfer zone but also a sediment-recharge zone that can substitute for the upstream; (iii) The downstream zone, which could be expected to be sensitive to these upstream conditions, which may have altered its morphosedimentary equilibrium and caused a retreat of the coastline and the estuary, and accelerate soil salinization in the coastal plain, records a completely different hydro-morphological behavior, where the role of high-magnitude, low-frequency events (<em>i.e</em>., exceptional floods) is highlighted to understand its recent geomorphological dynamics.</p><p>In a methodological point of view, this research is based on a systemic analysis used to better understand the hydro-sedimentary connectivity. Topographic field measurements were carried out on a small representative watershed (7 km²) in order to estimate sediment storage induced by agricultural practices. Results were then extrapolated at the watershed scale (1215 km²) according to a modeling approach. Channel adjustments including the linear and lateral erosion and sedimentation processes were then estimated according to twenty <sup>137</sup>Cs and <sup>210</sup>Pb dating carried out in the transfer zone as well as in the wetlands (Sebkhas and shotts) located at the outlet of the watershed.</p><p>As a conclusion, we indicate that Wadi Leben can be proposed as a model of hydro-morpho-sedimentary functioning showing the efficiency of sedimentary recharge as a key point of equilibrium of the watershed as soon as the river is capable of lateral displacements, thus joining the question of the re-dynamization of rivers in the perspective of the river-bed restoration. A balance sheet leading to the assessment of the sustainability of economic practices (agriculture, industry, tourism, fishing) in the context where change factors (water resources, hydrological regime, sedimentary stock) may affect the hydrosystem in its watershed in the more or less long term is also proposed.</p>

Research paper thumbnail of Vers une reconfiguration des territoires en Tunisie au temps de la décentralisation et de la communalisation intégrale

Prolifération des territoires et représentations territoriales de l’Union européenne

CIST2018 proceedings Représenter les territoires // Representing territories 72 Vers une reconfig... more CIST2018 proceedings Représenter les territoires // Representing territories 72 Vers une reconfiguration des territoires en Tunisie au temps de la décentralisation et de la communalisation intégrale AUTEURS Mourad BEN JELLOUL, Sami Yassine TURKI RÉSUMÉ La question des inégalités socio-spatiales a été au coeur de la mobilisation de 2010-2011 qui a conduit à l'instauration de la deuxième République tunisienne. L'accès aux services et aux équipements, à l'emploi et plus généralement le « droit au développement » ont été parmi les revendications populaires des régions de l'intérieur, au même titre que les appels au renouveau politique. Ainsi, l'ensemble de ces évolutions a mis les territoires au centre des transformations, avec l'émergence d'une nouvelle dynamique favorisant l'apparition d'un consensus politique sur la mise en place d'une décentralisation effective d'une part et la communalisation intégrale et immédiate du territoire d'autre part. Ce consensus laisse la place progressivement à un positionnement différencié des acteurs politiques, dont certains appellent à repenser l'engagement vers la décentralisation et la régionalisation, mettant en avant les risques d'exacerbation des tensions tribales ou régionales, dont les manifestations se sont multipliées depuis 2011.

Research paper thumbnail of Le fonctionnement des bassins-versants anthropisés

Armand Colin, Jul 1, 2020

International audienc

Research paper thumbnail of Dynamique géomorphologique holocène et occupation humaine dans le bassin-versant de l’Eure : apport d’une approche géoarchéologique multi-scalaire

Rencontres interdisciplinaires et interprofessionnelles Géosciences - Archéologie 2019, Jun 17, 2019

<jats:p>Localisé dans la partie occidentale du Bassin parisien, le bassin-versant de l'... more <jats:p>Localisé dans la partie occidentale du Bassin parisien, le bassin-versant de l'Eure présente une occupation humaine plurimillénaire. À l'interface entre plusieurs groupes culturels dès le Néolithique (groupes du Gord, de l'Artenac et de Bretagne), la vallée de l'Eure est un espace archéologique clef qui offre un cadre de recherche privilégié pour mettre en œuvre une approche géoarchéologique multiscalaire et diachronique combinant : (1) cartographie géomorphologique, comme outil permettant d'appréhender les biais taphonomiques dans la préservation des gisements archéologiques, (2) prospections géophysiques (tomographie de résistivité électrique) pour une reconstitution 2D de l'architecture du remblaiement alluvial, (3) acquisition et traitement des données stratigraphiques par carottage et analyses sédimentologiques. L'apport des archives sédimentaires fluviatiles est également mis en avant afin de reconstituer la trajectoire hydro-sédimentaire de l'Eure durant l'Holocène.</jats:p>

Research paper thumbnail of Cellular automata (CA) and Agent-Based Models (ABM) in response to different environmental problems: a review on French research over the last ten years

Research paper thumbnail of “La géographie de l’eau et son enseignement à l’Université”

Feuilles de Géographie, 2020

International audienc

Research paper thumbnail of Channel short-term adjustments following mobile dam lowering on a low-energy river: The Yerres River in the Seine Catchment (France)

Research paper thumbnail of Torrential activity facing global change in Southern French Alps

Research paper thumbnail of Synthesis, Characterization, and Antioxidant Activity of 2-methoxy-4 - ((4-methoxy phenyl imino) -methyl) phenol compounds

A Schiff base is a compound with functional group that contains a carbon-nitrogen double bond wit... more A Schiff base is a compound with functional group that contains a carbon-nitrogen double bond with the nitrogen atom conected to an aryl or alkyl group. It is usually formed by condensation of an aldehyde or keton with a primary amine. The 2-methoxy-4-((4-methoxyphenilimino) methyl) phenol compound could be synthesized from vanillin and panisidine using a water solvent by the stirrer method. The purpose of this research was to determine the characteristics and activity of 2-methoxy-4-((4-methoxyphenilimino)methyl)phenol. The synthesis of the Schiff base compound by stirrer method lasts for 30 minutes. The % yield determined the resulting compound of synthesis and its physical properties were observed based on shape, color, melting point, and chemical properties observed by the solubility test. Synthesis products were also characterized using FTIR, GC-MS, and H-NMR. The product compounds were then tested for their antioxidant activity using the DPPH method. The results showed that sy...

Research paper thumbnail of Chapitre 12. Le fonctionnement des bassins-versants anthropisés

Géographie de l'environnement, 2020

Research paper thumbnail of Tracing sedimentary mobilization from debris flows in the Peyronnelle sub-catchment of the Guil River (Queyras, Southern French Alps)

Research paper thumbnail of Spatial distribution and quantification of sediment storages in a “shiny schists” catchment: The Peynin catchment (Queyras, Southern French Alps)

Geomorphological, geological and geophysical investigations were carried out to estimate the amou... more Geomorphological, geological and geophysical investigations were carried out to estimate the amount of sediments stored in the Peynin catchment of about 15 km2, situated on the Queyras valley, on the Southern French Alps. Sediment storages were identiied, characterized and mapped on GIS from extensive ieldwork. Based on these data, two models of sediment thickness are proposed. he irst model is based on the modelling of the bedrock roof by using statistical functions (high estimate). he second model is ield‐based and results from the geological and geomorphological analyses of 46 cross‐sections (low estimate). To reduce the margins of error of these estimates, three seismic refraction proiles made during summer 2014 were integrated into the models. Volumes of sediments stored in the Peynin catchment are respectively estimated at 0.46 x 103.m3 (high estimate) and 0.13 x 103.m3 (low estimate). hey correspond to sediment thickness averages of ~30 m and ~9 m, respectively. In both cases...

Research paper thumbnail of Debris-flow functioning and their contribution to sedimentary budgets: the Peynin subcatchment of the Guil River (Upper Queyras, Southern French Alps)

Landform Analysis, 2018

The Peynin catchment (15 km2) is prone to catastrophic floods (June 1957 – Recurrence Interval R.... more The Peynin catchment (15 km2) is prone to catastrophic floods (June 1957 – Recurrence Interval R.I.>100 yr), June 2000 (R.I.-30 yr) with serious damages to infrastructure and buildings located at the outlet. In this paper, PIT tags tracers and Vensim modelling software are used to better assess the sediment delivery unsteadiness, and more specifically to evaluate the respective role of geomorphological processes on sediment supply during flood event. For the last 20 years, our results highlight a significant variability in sediment delivery from a tributary to another one. According to our studies, we suppose that two torrential tributaries of the Peynin river, the Peyronnelle and Three Arbres subcatchments (<2 km2, representing <15% of the Peynin catchment area) are responsible of 80% of the sediments observed at the outlet of the catchment. Several processes take a part of these sediment transfers, but the efficiency of the sediment cascade in this catchment can be explai...

Research paper thumbnail of Sediment Budget Analysis and Hazard Assessment in the Peynin, a Small Alpine Catchment (Upper Guil River, Southern Alps, France)

The EGU General Assembly, 2015

PosterInternational audienc

Research paper thumbnail of Volumes of sediment stored in an Alpine catchment using geological, geomorphological and geophysical expertise: Peynin catchment (Queyras, Southern French Alps)

The EGU General Assembly, 2017

Research paper thumbnail of Physical, social and institutional vulnerability assessment in small Alpine communities. Results of the SAMCO-ANR project in the Upper Guil Valley (French Southern Alps)

The EGU General Assembly, 2016

In the frame of the SAMCO project designed for mountain risk assessment in a context of global ch... more In the frame of the SAMCO project designed for mountain risk assessment in a context of global change, we developed a systemic approach to assess three specific components of vulnerability – physical, social and institu- tional – for the six municipalities of the Upper Guil catchment (Ristolas, Abries, Aiguilles, Château-Ville-Vieille, Molines-en-Queyras and St-Veran). Physical vulnerability, which represents total potential consequences of hazards on stakes, was estimated and mapped using a GIS model based on an empirical semi-quantitative indicator, the Potential Damage Index (PDI). This index allowed us to quantify and describe both direct (physical injury, structural and functional damage on buildings, network and land cover) and indirect consequences (socio-economic impacts) induced by hazards, by combining weighted parameters (age, state, material, function, etc.) reflecting the exposure of elements at risk. At least 1890 buildings, 367 km2 of land cover and 902 km of linear inf...

Research paper thumbnail of Reconstitution de l’environnement géomorphologique d’un sanctuaire d’époque romaine dans la plaine d’inondation de l’Eure moyenne : apports de la géoarchéologie fluviale

L’identification recente de paleochenaux dans la plaine alluviale de l’Eure moyenne, a proximite ... more L’identification recente de paleochenaux dans la plaine alluviale de l’Eure moyenne, a proximite immediate de vestiges d’un sanctuaire d’epoque romaine (lieu-dit « Bellevue », commune de Garennes-sur-Eure), offre des elements nouveaux pour replacer ce site archeologique dans son contexte paleoenvironnemental. Dans le cadre du PCR « Vallee de l’Eure : une riviere, des territoires », ce secteur a ete retenu comme « zone atelier » pour mettre en œuvre une approche geoarcheologique afin d’interpreter l’environnement geomorphologique de l’occupation antique (contexte topographique d’implantation) et d’eclairer les interrelations entre ce complexe cultuel, la plaine d’inondation de l’Eure et d’autres traces d’occupation proches, comme le sanctuaire de Guainville situe a moins d’un kilometre de distance sur le plateau du Mantois. La communication orale presentera les premiers resultats d’une approche interdisciplinaire et multi-donnees combinant (1) l’analyse de donnees topographiques a ha...

Research paper thumbnail of Gravel sediment tracing from small torrents to trunk channels using pit-tags method: A case study from the upper Guil catchment (Queyras, French Alps)

The EGU General Assembly, 2016

EGU 2016 Session GM9.1/HS11.15/NH1.24 Mountain streams : processes, channel morphology and knickp... more EGU 2016 Session GM9.1/HS11.15/NH1.24 Mountain streams : processes, channel morphology and knickpoint dynamics (co-organized) 1 Background and scientific context In mountainous areas, especially in large catchments with torrential tributaries, the production and sediment transport signiicantly increase ood impacts in the valley bottoms. The quantiication and characterisation of sedimentary transfers are therefore major challenges to provide better ood risk management. As a part of SAMCO (ANR 12 SENV-0004 SAMCO) project, for mountain hazard assessment in a context of global changes, we tried to improve the knowledge of these hydromorphological systems at both spatial and temporal scales, by identifying sediment supply and sediment dynamics from torrential tributaries to the trunk channel. A sediment budget was used as a tool for quantifying erosion, transport and deposition processes. This research is focused on a part of the sedimentary budget to understand the torrential processes ...

Research paper thumbnail of Synthesis of Schiff Base Compounds from Vanillin and p-Aminoacetophenone Using Lime Juice as a Natural Acid Catalyst and Their Utilization as Corrosion Inhibitors

Schiff bases can be synthesized by reacting Vanillin and p-aminoacetophenone using a natural acid... more Schiff bases can be synthesized by reacting Vanillin and p-aminoacetophenone using a natural acid catalyst such as lime juice (Citrus aurantifolia.) with the grinding method. The purposes of this study were to determine the characterization. The yield of synthesized compounds calculated and also determined the physical properties such as color and melting point. The product also characterized using NaOH reaction. Further characterization was carried out using FTIR and H-NMR. The synthesized compound is a yellow solid, slightly soluble in water, and has a melting point of 160-162 0C. The Mass obtained is 1,9459 g, with a percentage yield of 94,45%. The compound 1{4 [(4-hydroxy-3-methoxybenzylidene) -amino] -phenyl) -etanone reacts with NaOH to form a bright yellow color. This compound has an imine bond (-C = N-), which showed in the wavenumber 1583 cm. H-NMR characterization showed a typical chemical shifting of HC = Nat 8,5 ppm. The inhibition efficiency of these compounds ranged fr...

Research paper thumbnail of Use of terrestrial laser scanning (TLS) for monitoring geomorphic processes and sediment transfer in the Upper Guil Catchment (Queyras, French Alps)

In mountainous areas, especially in large river catchments with torrential tributaries, the produ... more In mountainous areas, especially in large river catchments with torrential tributaries, the production and sediment transport significantly increase flood impacts in the valley bottoms. For a better understanding of Alpine river catchments considered as complex systems, our research focuses on the Guil River catchment (Queyras, Southern French Alps). This catchment is largely prone to catastrophic summer floods (June 1957 (> R.I. 100 yr), June 2000 (R.I. 30 yr)...) whose impact is amplified by the strong hillslope-channel connectivity, inducing important volume of sediment supply into the main channel network. Consequently to these last flood events, serious damages to infrastructure and buildings were caused; mostly at confluences with debris flow prone tributaries, but also along some specific reaches constrained by protection structures. In the frame of SAMCO (ANR 12 SENV-0004 SAMCO) project, for mountain hazard mitigation, one of our purposes is to understand the hydro-geomor...

Research paper thumbnail of Systemic analysis of sediment connectivity in the Wadi Leben watershed, Tunisia (Mediterranean): Between morpho-structural potentialities, originality of the hydrographic network and societal reorganizations

&lt;p&gt;The Kneiss Islands and the outlet of the Wadi Leben watershed (Tunisia), is an i... more &lt;p&gt;The Kneiss Islands and the outlet of the Wadi Leben watershed (Tunisia), is an internationally recognized site, classified ZICO (1990) and Ramsar (2007) for the high fish productivity of its shallow waters, which makes these areas a favorable breeding ground for migratory birds. The difficulties to access to the sea make these areas slightly degraded. However, the sustainability of this site is now being jeopardized with anthropogenic pressure becoming progressively stronger on this littoral zone and the upstream watershed.&lt;/p&gt;&lt;p&gt;Our objective is to show the original hydro-sedimentary functioning of this Mediterranean watershed, shared between physical characteristics and intrusive agricultural practices in full reconversion (from local/traditional to international/globalized): (i) The upstream zone of the watershed is subject to sediment retention related to the implementation of a hydro-agricultural and anti-erosion system (water and soil conservation works); (ii) The intermediate zone, by its morpho-structural and sedimentogenetic characteristics, has favored the accumulation of sediments in the valley bottoms, which makes it not only a transfer zone but also a sediment-recharge zone that can substitute for the upstream; (iii) The downstream zone, which could be expected to be sensitive to these upstream conditions, which may have altered its morphosedimentary equilibrium and caused a retreat of the coastline and the estuary, and accelerate soil salinization in the coastal plain, records a completely different hydro-morphological behavior, where the role of high-magnitude, low-frequency events (&lt;em&gt;i.e&lt;/em&gt;., exceptional floods) is highlighted to understand its recent geomorphological dynamics.&lt;/p&gt;&lt;p&gt;In a methodological point of view, this research is based on a systemic analysis used to better understand the hydro-sedimentary connectivity. Topographic field measurements were carried out on a small representative watershed (7 km&amp;#178;) in order to estimate sediment storage induced by agricultural practices. Results were then extrapolated at the watershed scale (1215 km&amp;#178;) according to a modeling approach. Channel adjustments including the linear and lateral erosion and sedimentation processes were then estimated according to twenty &lt;sup&gt;137&lt;/sup&gt;Cs and &lt;sup&gt;210&lt;/sup&gt;Pb dating carried out in the transfer zone as well as in the wetlands (Sebkhas and shotts) located at the outlet of the watershed.&lt;/p&gt;&lt;p&gt;As a conclusion, we indicate that Wadi Leben can be proposed as a model of hydro-morpho-sedimentary functioning showing the efficiency of sedimentary recharge as a key point of equilibrium of the watershed as soon as the river is capable of lateral displacements, thus joining the question of the re-dynamization of rivers in the perspective of the river-bed restoration. A balance sheet leading to the assessment of the sustainability of economic practices (agriculture, industry, tourism, fishing) in the context where change factors (water resources, hydrological regime, sedimentary stock) may affect the hydrosystem in its watershed in the more or less long term is also proposed.&lt;/p&gt;

Research paper thumbnail of Vers une reconfiguration des territoires en Tunisie au temps de la décentralisation et de la communalisation intégrale

Prolifération des territoires et représentations territoriales de l’Union européenne

CIST2018 proceedings Représenter les territoires // Representing territories 72 Vers une reconfig... more CIST2018 proceedings Représenter les territoires // Representing territories 72 Vers une reconfiguration des territoires en Tunisie au temps de la décentralisation et de la communalisation intégrale AUTEURS Mourad BEN JELLOUL, Sami Yassine TURKI RÉSUMÉ La question des inégalités socio-spatiales a été au coeur de la mobilisation de 2010-2011 qui a conduit à l'instauration de la deuxième République tunisienne. L'accès aux services et aux équipements, à l'emploi et plus généralement le « droit au développement » ont été parmi les revendications populaires des régions de l'intérieur, au même titre que les appels au renouveau politique. Ainsi, l'ensemble de ces évolutions a mis les territoires au centre des transformations, avec l'émergence d'une nouvelle dynamique favorisant l'apparition d'un consensus politique sur la mise en place d'une décentralisation effective d'une part et la communalisation intégrale et immédiate du territoire d'autre part. Ce consensus laisse la place progressivement à un positionnement différencié des acteurs politiques, dont certains appellent à repenser l'engagement vers la décentralisation et la régionalisation, mettant en avant les risques d'exacerbation des tensions tribales ou régionales, dont les manifestations se sont multipliées depuis 2011.

Research paper thumbnail of Le fonctionnement des bassins-versants anthropisés

Armand Colin, Jul 1, 2020

International audienc

Research paper thumbnail of Dynamique géomorphologique holocène et occupation humaine dans le bassin-versant de l’Eure : apport d’une approche géoarchéologique multi-scalaire

Rencontres interdisciplinaires et interprofessionnelles Géosciences - Archéologie 2019, Jun 17, 2019

<jats:p>Localisé dans la partie occidentale du Bassin parisien, le bassin-versant de l'... more <jats:p>Localisé dans la partie occidentale du Bassin parisien, le bassin-versant de l'Eure présente une occupation humaine plurimillénaire. À l'interface entre plusieurs groupes culturels dès le Néolithique (groupes du Gord, de l'Artenac et de Bretagne), la vallée de l'Eure est un espace archéologique clef qui offre un cadre de recherche privilégié pour mettre en œuvre une approche géoarchéologique multiscalaire et diachronique combinant : (1) cartographie géomorphologique, comme outil permettant d'appréhender les biais taphonomiques dans la préservation des gisements archéologiques, (2) prospections géophysiques (tomographie de résistivité électrique) pour une reconstitution 2D de l'architecture du remblaiement alluvial, (3) acquisition et traitement des données stratigraphiques par carottage et analyses sédimentologiques. L'apport des archives sédimentaires fluviatiles est également mis en avant afin de reconstituer la trajectoire hydro-sédimentaire de l'Eure durant l'Holocène.</jats:p>

Research paper thumbnail of Cellular automata (CA) and Agent-Based Models (ABM) in response to different environmental problems: a review on French research over the last ten years

Research paper thumbnail of “La géographie de l’eau et son enseignement à l’Université”

Feuilles de Géographie, 2020

International audienc

Research paper thumbnail of Channel short-term adjustments following mobile dam lowering on a low-energy river: The Yerres River in the Seine Catchment (France)

Research paper thumbnail of Torrential activity facing global change in Southern French Alps

Research paper thumbnail of Synthesis, Characterization, and Antioxidant Activity of 2-methoxy-4 - ((4-methoxy phenyl imino) -methyl) phenol compounds

A Schiff base is a compound with functional group that contains a carbon-nitrogen double bond wit... more A Schiff base is a compound with functional group that contains a carbon-nitrogen double bond with the nitrogen atom conected to an aryl or alkyl group. It is usually formed by condensation of an aldehyde or keton with a primary amine. The 2-methoxy-4-((4-methoxyphenilimino) methyl) phenol compound could be synthesized from vanillin and panisidine using a water solvent by the stirrer method. The purpose of this research was to determine the characteristics and activity of 2-methoxy-4-((4-methoxyphenilimino)methyl)phenol. The synthesis of the Schiff base compound by stirrer method lasts for 30 minutes. The % yield determined the resulting compound of synthesis and its physical properties were observed based on shape, color, melting point, and chemical properties observed by the solubility test. Synthesis products were also characterized using FTIR, GC-MS, and H-NMR. The product compounds were then tested for their antioxidant activity using the DPPH method. The results showed that sy...

Research paper thumbnail of Chapitre 12. Le fonctionnement des bassins-versants anthropisés

Géographie de l'environnement, 2020

Research paper thumbnail of Tracing sedimentary mobilization from debris flows in the Peyronnelle sub-catchment of the Guil River (Queyras, Southern French Alps)

Research paper thumbnail of Spatial distribution and quantification of sediment storages in a “shiny schists” catchment: The Peynin catchment (Queyras, Southern French Alps)

Geomorphological, geological and geophysical investigations were carried out to estimate the amou... more Geomorphological, geological and geophysical investigations were carried out to estimate the amount of sediments stored in the Peynin catchment of about 15 km2, situated on the Queyras valley, on the Southern French Alps. Sediment storages were identiied, characterized and mapped on GIS from extensive ieldwork. Based on these data, two models of sediment thickness are proposed. he irst model is based on the modelling of the bedrock roof by using statistical functions (high estimate). he second model is ield‐based and results from the geological and geomorphological analyses of 46 cross‐sections (low estimate). To reduce the margins of error of these estimates, three seismic refraction proiles made during summer 2014 were integrated into the models. Volumes of sediments stored in the Peynin catchment are respectively estimated at 0.46 x 103.m3 (high estimate) and 0.13 x 103.m3 (low estimate). hey correspond to sediment thickness averages of ~30 m and ~9 m, respectively. In both cases...

Research paper thumbnail of Debris-flow functioning and their contribution to sedimentary budgets: the Peynin subcatchment of the Guil River (Upper Queyras, Southern French Alps)

Landform Analysis, 2018

The Peynin catchment (15 km2) is prone to catastrophic floods (June 1957 – Recurrence Interval R.... more The Peynin catchment (15 km2) is prone to catastrophic floods (June 1957 – Recurrence Interval R.I.>100 yr), June 2000 (R.I.-30 yr) with serious damages to infrastructure and buildings located at the outlet. In this paper, PIT tags tracers and Vensim modelling software are used to better assess the sediment delivery unsteadiness, and more specifically to evaluate the respective role of geomorphological processes on sediment supply during flood event. For the last 20 years, our results highlight a significant variability in sediment delivery from a tributary to another one. According to our studies, we suppose that two torrential tributaries of the Peynin river, the Peyronnelle and Three Arbres subcatchments (<2 km2, representing <15% of the Peynin catchment area) are responsible of 80% of the sediments observed at the outlet of the catchment. Several processes take a part of these sediment transfers, but the efficiency of the sediment cascade in this catchment can be explai...

Research paper thumbnail of Sediment Budget Analysis and Hazard Assessment in the Peynin, a Small Alpine Catchment (Upper Guil River, Southern Alps, France)

The EGU General Assembly, 2015

PosterInternational audienc

Research paper thumbnail of Volumes of sediment stored in an Alpine catchment using geological, geomorphological and geophysical expertise: Peynin catchment (Queyras, Southern French Alps)

The EGU General Assembly, 2017

Research paper thumbnail of Physical, social and institutional vulnerability assessment in small Alpine communities. Results of the SAMCO-ANR project in the Upper Guil Valley (French Southern Alps)

The EGU General Assembly, 2016

In the frame of the SAMCO project designed for mountain risk assessment in a context of global ch... more In the frame of the SAMCO project designed for mountain risk assessment in a context of global change, we developed a systemic approach to assess three specific components of vulnerability – physical, social and institu- tional – for the six municipalities of the Upper Guil catchment (Ristolas, Abries, Aiguilles, Château-Ville-Vieille, Molines-en-Queyras and St-Veran). Physical vulnerability, which represents total potential consequences of hazards on stakes, was estimated and mapped using a GIS model based on an empirical semi-quantitative indicator, the Potential Damage Index (PDI). This index allowed us to quantify and describe both direct (physical injury, structural and functional damage on buildings, network and land cover) and indirect consequences (socio-economic impacts) induced by hazards, by combining weighted parameters (age, state, material, function, etc.) reflecting the exposure of elements at risk. At least 1890 buildings, 367 km2 of land cover and 902 km of linear inf...

Research paper thumbnail of Reconstitution de l’environnement géomorphologique d’un sanctuaire d’époque romaine dans la plaine d’inondation de l’Eure moyenne : apports de la géoarchéologie fluviale

L’identification recente de paleochenaux dans la plaine alluviale de l’Eure moyenne, a proximite ... more L’identification recente de paleochenaux dans la plaine alluviale de l’Eure moyenne, a proximite immediate de vestiges d’un sanctuaire d’epoque romaine (lieu-dit « Bellevue », commune de Garennes-sur-Eure), offre des elements nouveaux pour replacer ce site archeologique dans son contexte paleoenvironnemental. Dans le cadre du PCR « Vallee de l’Eure : une riviere, des territoires », ce secteur a ete retenu comme « zone atelier » pour mettre en œuvre une approche geoarcheologique afin d’interpreter l’environnement geomorphologique de l’occupation antique (contexte topographique d’implantation) et d’eclairer les interrelations entre ce complexe cultuel, la plaine d’inondation de l’Eure et d’autres traces d’occupation proches, comme le sanctuaire de Guainville situe a moins d’un kilometre de distance sur le plateau du Mantois. La communication orale presentera les premiers resultats d’une approche interdisciplinaire et multi-donnees combinant (1) l’analyse de donnees topographiques a ha...

Research paper thumbnail of Gravel sediment tracing from small torrents to trunk channels using pit-tags method: A case study from the upper Guil catchment (Queyras, French Alps)

The EGU General Assembly, 2016

EGU 2016 Session GM9.1/HS11.15/NH1.24 Mountain streams : processes, channel morphology and knickp... more EGU 2016 Session GM9.1/HS11.15/NH1.24 Mountain streams : processes, channel morphology and knickpoint dynamics (co-organized) 1 Background and scientific context In mountainous areas, especially in large catchments with torrential tributaries, the production and sediment transport signiicantly increase ood impacts in the valley bottoms. The quantiication and characterisation of sedimentary transfers are therefore major challenges to provide better ood risk management. As a part of SAMCO (ANR 12 SENV-0004 SAMCO) project, for mountain hazard assessment in a context of global changes, we tried to improve the knowledge of these hydromorphological systems at both spatial and temporal scales, by identifying sediment supply and sediment dynamics from torrential tributaries to the trunk channel. A sediment budget was used as a tool for quantifying erosion, transport and deposition processes. This research is focused on a part of the sedimentary budget to understand the torrential processes ...

Research paper thumbnail of Synthesis of Schiff Base Compounds from Vanillin and p-Aminoacetophenone Using Lime Juice as a Natural Acid Catalyst and Their Utilization as Corrosion Inhibitors

Schiff bases can be synthesized by reacting Vanillin and p-aminoacetophenone using a natural acid... more Schiff bases can be synthesized by reacting Vanillin and p-aminoacetophenone using a natural acid catalyst such as lime juice (Citrus aurantifolia.) with the grinding method. The purposes of this study were to determine the characterization. The yield of synthesized compounds calculated and also determined the physical properties such as color and melting point. The product also characterized using NaOH reaction. Further characterization was carried out using FTIR and H-NMR. The synthesized compound is a yellow solid, slightly soluble in water, and has a melting point of 160-162 0C. The Mass obtained is 1,9459 g, with a percentage yield of 94,45%. The compound 1{4 [(4-hydroxy-3-methoxybenzylidene) -amino] -phenyl) -etanone reacts with NaOH to form a bright yellow color. This compound has an imine bond (-C = N-), which showed in the wavenumber 1583 cm. H-NMR characterization showed a typical chemical shifting of HC = Nat 8,5 ppm. The inhibition efficiency of these compounds ranged fr...

Research paper thumbnail of Use of terrestrial laser scanning (TLS) for monitoring geomorphic processes and sediment transfer in the Upper Guil Catchment (Queyras, French Alps)

In mountainous areas, especially in large river catchments with torrential tributaries, the produ... more In mountainous areas, especially in large river catchments with torrential tributaries, the production and sediment transport significantly increase flood impacts in the valley bottoms. For a better understanding of Alpine river catchments considered as complex systems, our research focuses on the Guil River catchment (Queyras, Southern French Alps). This catchment is largely prone to catastrophic summer floods (June 1957 (> R.I. 100 yr), June 2000 (R.I. 30 yr)...) whose impact is amplified by the strong hillslope-channel connectivity, inducing important volume of sediment supply into the main channel network. Consequently to these last flood events, serious damages to infrastructure and buildings were caused; mostly at confluences with debris flow prone tributaries, but also along some specific reaches constrained by protection structures. In the frame of SAMCO (ANR 12 SENV-0004 SAMCO) project, for mountain hazard mitigation, one of our purposes is to understand the hydro-geomor...