ANDRIEU , Julien

We studied, at local scale, how the landscape dynamics of the Saloum and Casamance (Senegal)and The Gambia can reveal environmental crises and the resilience of agrarian. The method isbased on remote sensing diachrony in land cover maps, field observations (landscape andbotany), and interviews on recent landscape changes and agriculture. The...

National audience

This thesis aims the mapping and quantification of vegetation land cover changes in West-African coastal zone usingLANDSAT TM images. A multistage unsupervised classification has been designed for this purpose. The objective was the mapping of land cover, with a predefined typology, by means of a reproducible method that could be easily...

International audience

International audience

A multisca/e and multisatellite remote sensing approach has been set up in order to study vegetation changes, in particular the forest-savanna limit, first over a region including Côte d'Ivoire and Bénin with an 8 km resolution, from 1981 to 2006, then over Côte d'Ivoire on/y, with a 250 m resolution, from 2002 to 2014. Both the NOVI time...

L'HDR décline trois points : premièrement, le questionnement de certains concepts, l'épistémologie et les méthodes de la biogéographie pour justifier le choix d'une approche quantitative et appliquée de la biogéographie comprise comme une science de la relation nature-société. Deuxièmement, le volume présente les particularités des recherches...

The last IPCC report (Intergovernmental Panel on Climate Change) presents numerous consequences of temperature elevations on terrestrial biodiversity. Spatial modeling is a way to forecast and to go beyond field observation by emancipating constraints thereof. Dynamic models and climate data with low spatial resolution, allow to develop models...

The mangrove areas in Senegal have fluctuated considerably over the last few decades, and it is therefore important to monitor the evolution of forest cover in order to orient and optimise forestry policies. This study presents a method for mapping plant formations to monitor and study changes in zonation within the mangroves of Senegal. Using...

International audience

International audience

The West African littoral strip between the Delta of Sine‐Saloum and the Rio Mansôa corresponds to the transition from sudanian to guinean domains. Three criteria differentiate the wooded landscapes in this area : latitudinal climatic gradient, alternate occurrences of low plateaux and tidal mud flats, numerous practises and uses of local rural...

National audience

Le dernier rapport du GIEC fait état de nombreuses conséquences possibles sur la biodiversité terrestre induites par l'élévation des températures. Les modifications des aires de distribution des espèces végétales sont le résultat de processus complexes : la reproduction et la mortalité. L'objectif de cette étude est de présenter les apports de...

International audience

International audience

International audience

In the current context of environmental changes, mapping vegetation and monitoring its changes are necessary to meet the needs of those involved in protecting and conserving biodiversity. The major national mapping programs, such as the IGN "Forest" database, do not allow for temporal monitoring due to the low frequency of updates and the...

The mangrove areas in Senegal have fluctuated considerably over the last few decades, and it is therefore important to monitor the evolution of forest cover in order to orient and optimise forestry policies. This study presents a method for mapping plant formations to monitor and study changes in zonation within the mangroves of Senegal. Using...

International audience