L'évolution du risque d'inondation par les cours d'eau méditerranéens français : le rôle de l'accumulation dans le lit majeur (The evolution of flood risk by mediterranean rivers : the part of accumulation in the flood plains) In: Bulletin de l'Association de géographes français, 81e année, 2004-1 (mars). Proximités spatiales dans la ville. Risques naturels, risques de sociétés. pp. 64-74. Résumé Dans de nombreux cours d'eau méditerranéens français, l'accumulation des formations fines du lit majeur commence au cours de l'Antiquité et se prolonge pendant les périodes médiévale, moderne et contemporaine. La datation isotopique des derniers dépôts de crue du Gardon d'Anduze et de l'Ouvèze montre que cette tendance a perduré au cours de la deuxième moitié du XXe siècle. Les nombreux aménagements effectués ou prévus doivent prendre en compte cette évolution.

No abstract

La place de l'hydrogéomorphologie dans les études d'inondation en France méditerranéenne / The contribution of hydrogeomorphology in flood hazard assessment: a review of the situation in southern France

Abstract. - The floods which happened in the seventies and eighties and the regular increase of damages encouraged the French government to install an efficient policy of natural hazard prevention in 1982. It gave the definition of a methodology of very elaborate studies that was especially adapted to floods in plains, the most frequent at that time. But, paradoxically, the most important events that we have known for about 15 years, at Auch, at the Grand-Bornand, at Nimes and at Vaison-la-Romaine have been the result of different hydrological phenomena (urban run-off ; torrential floods). They contributed to progressively complete the legislative and regulation rules which to day should lead to the passage of the Projects of Hazard Prevention (P.P.R. in French) and to develop the knowledge of natural phenomena in a more global and pluridisciplinary approach.

We present here some aspects of the natural risk management (floods, landslides, seisms) in Europe. The regulations, the actors and the various levels of decisions are different. The cartography is present everywhere with nevertheless different purposes according to countries. The place of the insurances is not identical in all the countries.