Search results for "soil"
showing 10 items of 3493 documents
Biodiversité des sols viticoles: un héritage des modes d'occupation et des pratiques culturales anciennes?
2018
3 pages; National audience
Relationships between societies and their environment in the Sahel in southwestern Niger over the past four thousand years : a geoarchaeological appr…
2013
The Sahel, a zone between the Sahara Desert and the Sudan forests, is currently experiencing major environmental changes. Since the droughts in 1970s and 1980s, and with the high population growth rate, vegetation cover has deteriorated considerably, contributing to increased runoff and soil erosion. Starting from this observation, we undertook the study of past societies in the Niamey region, to assess their impact on the environment. The lack of archaeological data meant that it was necessary to identify key indicators of occupation during the Neolithic and the Iron Age. In addition to providing new evidence to date the Neolithic site of Kirkissoy, a sedimentary study was conducted on a p…
Cartographie de la diversité des sols viticoles de versant par imagerie à haute résolution : contribution à la connaissance des terroirs
2014
The Burgundian vineyard hillslopes (Côte-d’Or, France) exhibit a high diversity of soils resulting from the combination of several natural and anthropogenic factors acting at various spatio-temporal scales. The soil types have major role in viticulture, since they partly determine wine-growing quality. However, soil undergoes important degradation caused by hydric erosion and vineyard management practices. To control this soil heritage for a sustained viticulture in Côte-d’Or, a better knowledge of soil is necessary. The objectives of this work is to characterise vineyard soils and to identify the factors governing their diversity using an interdisciplinary approach crossing geology, geomor…
Mapping soil and substratum at a very high spatial resolution in the hillslope of Couchey (France)
2012
International audience; In this work, we present a method based on very high spatial resolution (VHSR) aerial images acquired in the visible domain and that map soil surface diversity at the hillslope scale with a spatial resolution of a few centimeters. This method combines aerial VHSR image classification with local soil sampling. Principal component analysis (PCA) and non-supervised classification was performed on image characteristics to define soil surface characteristic classes (SSC). Then soil surface mapping was combined with soil surface descriptions and soil profiles to define soil types by physical and chemical characteristics. As soil results from parent material alteration, ide…
Vineyard soils and landscapes of the Burgundy Côte (France): a historical construction worth preserving
2012
International audience; The construction of vineyard landscapes along the Burgundy Côte is the result of geological processes and of human labour. Substratum diversity in this vineyard is the result of a very long history explained by the diversity of Jurassic sedimentary facies and Tertiary tectonic activity. The nature and thickness of Quaternary deposits (Weichselian scree debris and alluvial fans) reflect sediment dynamics concurrent with the last glaciation. As soon as humans started to occupy and cultivate these slopes, the changes they made in the land through crop development and roads began to structure the vineyard plots in a lasting way. The footprint of vine work in soils can be…
Erosion des sols viticoles par les évènements orageux (Vosne-Romanée) : quels risques pour le futur ?
2007
International audience; Des différences de maturité des raisins ont été constatées, en particulier entre les fruits produits sur les sols clairs et ceux provenant de vignes poussant sur des sols plus sombres. Ce constat a été testé par une expérience de mesures de températures en continu dans le Clos Vougeot et dans Les Cras, deux stations situées à la même altitude, distantes d'environ cent mètres et caractérisées par des sols plus bruns et plus argileux pour la première et par des sols plus clairs et pierreux pour la seconde. Dans les deux stations, les mesures de températures automatiques et régulières (toutes les trente minutes) ont été réalisées pendant un an à partir du 18 mai 2003, à…
Capability of a high resolution hydroclimatic modelling chain to simulate soil water deficit indices for Douglas-fir and common Beeches over Burgundy.
2016
During the 2003 drought and heat wave event, douglas-fir and common beech stands in Burgundy have been heavily affected, and presented symptoms of dieback and mortality. This event seems to be the first occurrence of expected climatic changes in the near future and questions their sustainability in Burgundy since their climate vulnerability is mainly due to the amplitude and accumulated water constraints exercised during their growing cycle. In the context of climate change and in order to provide information to forest managers who partly rely on a mapping of the climatic constraints until the end of this century, this work explores the ability of a high resolution hydroclimatic modelling c…
Capacity of a high resolution hydroclimatic modelling chair to simulate soil water deficit indexes for Douglas-fir and common Beeches over Burgundy
2016
During the 2003 drought and heat wave event, douglas-fir and common beech stands in Burgundy have been heavily affected, and presented symptoms of dieback and mortality. This event seems to be the first occurrence of expected climatic changes in the near future and questions their sustainability in Burgundy since their climate vulnerability is mainly due to the amplitude and accumulated water constraints exercised during their growing cycle. In the context of climate change and in order to provide information to forest managers who partly rely on a mapping of the climatic constraints until the end of this century, this work explores the ability of a high resolution hydroclimatic modelling c…
Application of a simple algorithm to estimate daily evapotranspiration from NOAA–AVHRR images for the Iberian Peninsula
2007
International audience; Evapotranspiration (ET) is a key process in land surface–atmosphere studies. It mainly depends on water availability and incoming solar radiation and then reflects the interactions between surface water processes and climate. In this paper, a methodology for retrieving ET from low spatial resolution remote sensing data is presented. It is based on the evaporative fraction concept, and it has been applied to Advanced Very High Resolution Radiometer (AHVRR) data acquired over the Iberian Peninsula. The methodology does not require other data than the data provided by the satellite and may be applied to areas with almost spatially constant atmospheric conditions and whi…
Retrieval of evapotranspiration over the Alpilles/ReSeDA experimental site using airborne POLDER sensor and a thermal camera
2005
Abstract Knowledge of land surface evapotranspiration is of prime interest for environmental applications, such as optimizing irrigation water use, especially in arid and semiarid rangelands where water shortage is a critical problem. Numerous methods aiming at estimating evapotranspiration have been proposed in the literature. In the current paper, we assess the potential of the evaporative fraction based on the S-SEBI (Simplified Surface Energy Balance Index) concept for estimating instantaneous evapotranspiration, and extend this potential to the retrieval of daily evapotranspiration (ETd). To this end, a feasible and operational method is developed, which allows mapping instantaneous an…