Papers by Anne-Véronique Auzet
Scientific registration n° : 734 Symposium n° : 2 Presentation : poster Mots clés : plateau basal... more Scientific registration n° : 734 Symposium n° : 2 Presentation : poster Mots clés : plateau basaltique, sol argileux, conductivité hydraulique, semis direct, pratiques culturales.
Annales de Géographie, 1995
Dans le sud du Brésil (états de Parana, Santa Catarina et Rio Grande do Sul), les sols à très hau... more Dans le sud du Brésil (états de Parana, Santa Catarina et Rio Grande do Sul), les sols à très haute teneur en argile issus d'un épais basaltique sont, depuis une vingtaine d'années, mis en valeur par un système à base de grandes cultures (soja, maïs, céréales) qui a succédé à la canne à sucre. La fragilité des sols, un défrichement assez anarchique, une mécanisation lourde, un découpage foncier hérité d'une colonisation récente et un système économique chaotique constituent les principaux facteurs d'une érosion importante et généralisée. Cela a conduit les agriculteurs à adopter des stratégies de conservation dynamiques et originales sous l'impulsion de grandes coopératives agricoles et de centres de recherches agronomiques souvent privés. Les pratiques conservationnistes des producteurs agricoles, plus particulièrement ceux d'exploitations de tailles moyennes (taille comprise entre 50 et 500 ha), sont passées en l'espace de vingt ans par plusieurs étapes...
Revue internationale de géomatique, 2010
ABSTRACT La restauration de l'espace de mobilité d'un cours d'eau suppose... more ABSTRACT La restauration de l'espace de mobilité d'un cours d'eau suppose d'analyser l'évolution historique de son tracé et de caractériser des vitesses de migration de ses méandres. La méthode proposée vise à intégrer l'incertitude associée à chaque tracé sous forme de zone d'incertitude de part et d'autre des tracés des berges. Les résultats obtenus sur la Bruche (BasRhin, France) mettent en évidence une variabilité spatiale des distances de migration des 55 méandres analysés avec des vitesses moyennes de migration. La limite de la méthode réside dans l'étude des migrations à l'échelle annuelle pour lesquelles la migration peut être inférieure ou égale aux incertitudes notamment en zones boisées. Une analyse des paramètres de contrôle de la migration est réalisée en intégrant les incertitudes. La donnée LiDAR (Light Detection And Ranging) permet d'enrichir les données classiquement utilisées dans les études diachroniques.
Boardman/Soil Erosion in Europe, 2006
France has a large variety of landscapes, including high mountains in the east and south-west (Al... more France has a large variety of landscapes, including high mountains in the east and south-west (Alps, Pyrenees) and extensive plains and plateaux of the Aquitaine and the Paris basins open to the west, with altitudes mostly below 200 m. Ancient Hercynian massifs lie around their rims. Among them, the Vosges and the Massif Central were thrown outwards at the time of uplifting of the Alpine range. The Massif Central contains many volcanoes. Massifs of the Tertiary Period (Jura, Pre-Alps) are made up of folded sedimentary rock, mainly limestone. Main river valleys mark the eastern part with the Rhone valley that opens towards the Mediterranean and, in the north, the western part of the upper Rhine floodplain.
Soil Science, 2002
... Water Transfer and Mobile Water Content Measurement in A Cultivated Crusted Soil. Roulier, St... more ... Water Transfer and Mobile Water Content Measurement in A Cultivated Crusted Soil. Roulier, Stéphanie 1 ; Angulo-Jaramillo, Rafael 1 ; Bresson, Louis-Marie 2 ; Auzet, Anne-Véronique 3 ; Gaudet, Jean-Paul 1 ; Bariac, Thierry 4. ... E-mail. [email protected]. ...
Soil and Tillage Research, 2009
Conservation tillage (CT) constitutes one way to limit on-and off-site impacts of soil erosion. L... more Conservation tillage (CT) constitutes one way to limit on-and off-site impacts of soil erosion. Literature analysis suggests that CT is more effective in reducing soil erosion than surface runoff. The effect on runoff mitigation may be rather limited and in some cases, CT causes runoff to increase compared to conventional tillage systems. From the review of infiltrometry and runoff studies, we have concluded that runoff mitigation can be explained by infiltrability improvement of the soil profile and limitation of surface structural degradation.
Land Use Policy, 2009
The inventory of muddy floods in France indicates that the occurrence of these events seriously i... more The inventory of muddy floods in France indicates that the occurrence of these events seriously increased in the North West and the East of the country. Muddy floods triggering can largely be explained by physical characteristics such as a hilly topography, soils prone to crust, and/or heavy rainfall in spring. Although the physical processes are well known by now and despite increasing information about the need of mitigation measures, no significant reduction of these disasters has been registered. Therefore, this should be explained by factors others than scientific reasons or technical knowledge acquisition difficulties.
Land Degradation & Development, 2010
Muddy floods, i.e. water flowing from agricultural fields and carrying large quantities of soil, ... more Muddy floods, i.e. water flowing from agricultural fields and carrying large quantities of soil, affect routinely numerous municipalities of central Belgium, northern France and southern England. A comparison of flood frequency between different European regions is difficult, because of the lack of a uniform and official database as well as the landscape heterogeneity of administrative entities. Agri-environmental measures [AEMs; e.g. grass buffer strips (GBS)] can contribute to the control of muddy floods but their installation is voluntary and depends therefore on farmers' willingness. Actions to increase awareness and to inform the farmers proved to increase drastically their participation rate in AEM programmes. In all the studied regions, flood prone areas are increasingly taken into account to define land approved for development. Moreover, several schemes for the control of muddy floods have also been proposed at the regional scale. However, there is a spatial mismatch between the scale at which muddy floods are triggered (small catchment scale) and the scale at which public authorities can operate (municipality, grouping of municipalities, delineated flood prone areas, river basin). In future, beside curative measures (e.g. retention ponds and dams), farming techniques preventing runoff and erosion in the field (e.g. conservation tillage) should be encouraged. This could be achieved by the creation of a new AEM. Moreover, guidelines for the location of AEMs could usefully be introduced. Existing flood control schemes should also be systematically carried out by catchment agencies including legal, environmental and financial expertise. These agencies should be set up for local groupings of municipalities and provide them technical assistance to equip the flood prone areas and carry out maintenance of the implemented control measures.
Hydrological Processes, 1999
In the region of the basaltic plateau in Southern Brazil, problems of runo and erosion on the dee... more In the region of the basaltic plateau in Southern Brazil, problems of runo and erosion on the deep ferrallitic soils are becoming increasingly recognized. Land use change from conventional tillage using disk plough to no-tillage on residues without terracing occurred at the beginning of the 1990s and it spread very quickly. Measurements of runo and sediment concentrations on 1 m 2 plots receiving natural rainfall and simulated rainfall under dierent crops with dierent stages of growth and dierent tillage systems, ®eld surveys and measurements of rills and gullies in nested experimental catchments indicate a relative decrease of runo on slopes but an increase of subsurface¯ow, and a marked decrease of sheet and rill erosion and soil loss from plot to catchment scales. Nevertheless, the extension of parts of the gully system is still continuing, strongly in¯uenced by extreme rainfall.
Earth Surface Processes and Landforms, 2003
Soil surface characteristics (SSCs) have a strong influence on the infiltration properties at the... more Soil surface characteristics (SSCs) have a strong influence on the infiltration properties at the soil surface. They can explain spatial variations in the infiltration processes observed under natural rainfall for relatively little-differentiated material and can help us to understand the surface and subsurface hydrology of landslides, representative of some of black marls landscapes of the French southern Alps. This paper presents the results of investigations into the influence of SSCs using careful morphological description, in situ tension-disc infiltrometry and statistical analysis (hierarchical ascending classification and stepwise discriminant analysis). The site studied is the Super-Sauze earthflow. The selected infiltration and runoff variables were described for 233 microplots chosen all over the earthflow. The results show that an approach based on a description of relevant variables influencing water infiltration can validate a typology based on 'expert' knowledge. Hydraulic conductivity at saturation was measured on 36 undisturbed soil cores and at low negative pressure heads on 83 microplots: the dispersion exceeds three orders of magnitude at each pressure head. A statistical analysis of the data set obtained by describing selected variables showed the relevance of the black marl descriptors when defining types of SSC that enable us to distinguish significant hydrodynamical behaviour. This leads us to suggest a distribution of hydraulic conductivity curves near saturation for each SSC type, which can be used as a key to distribute local hydraulic conductivity values adapted to black marl hillslopes. As well as the types of SSC at a microplot scale leading to types of hydrodynamic properties, the typology of combinations of SSCs at a coarser scale should lead to types of hydrological response and to identification of hydrological and geomorphological response units.
... PAYRAUDEAU Sylvain(1)*, GLATRON Sandrine(2), ROZAN Anne(3), ELEUTERIO Julian(1, 3) AUZET Anne... more ... PAYRAUDEAU Sylvain(1)*, GLATRON Sandrine(2), ROZAN Anne(3), ELEUTERIO Julian(1, 3) AUZET Anne-Véronique(4) WEBER Christiane(2), LIEBAULT Frédéric(5). ... l'extension des zones inondées Sensibilité des modèles hydrauliques à la qualité de ...
The delivery of detached sediment by overland flow from disjunct agricultural fields to stream ch... more The delivery of detached sediment by overland flow from disjunct agricultural fields to stream channels has important impacts on the river (eco)system and surface water quality. The degree of connectivity between overland flow source areas and the permanent drainage network is affected by the presence of small-scale man-induced linear elements, such as ditches, tracks, headlands and dead furrows, which may increase the efficiency of water and sediment transfers and the extension of the contributing areas. The network pattern of these elements has been shown to vary strongly in space and time depending on land use, field size, field configuration and the agricultural calendar. So far, regional-scale sediment delivery models do not account for these structures. They consider terrestrial runoff pathways towards the stream channels through surface parameters like slope angle, roughness, vegetation cover etc. but they do not consider parameters related to linear elements, often non-perma...
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Papers by Anne-Véronique Auzet