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In the framework of the GEWEX / Rhone project, which aims at developing a regional model of the surface energy and water cycle in the Rhone basin, the flow of the Saone river basin (30000) km2 was modelled with the MARTHE model. The paper first describes the functionalities of MARTHE and then the modelling of the Saone basin with a 2 km grid at a daily time step over a 14 years (August 1981 to July 1995) using different surface hydrological models (soil models) : these soil models require from 3 to 91 parameters over the entire basin. A comparison of the results shows that the daily flows at the 52 gauging stations of the Saone are best modelled with the GR4 soil model using only 3 parameters. This advocates the gathering of additional data namely aquifer data and soil saturation in order to avoid over-parameterisation.

The paper presents the French national effort undertaken these 5 last years in order to build a hydrological modelisation of the Rhone catchment, coupling the surface and the atmosphere at regional scale. The modelling strategy is based on the coupling of the operational surface model (the ISBA SVAT scheme), the snow model (CROCUS) of Meteo-France and the distributed hydrological model MODCOU developed at Centre d'Informatique Géologique de l'Ecole Nationale Supérieure des Mines de Paris (CIG/ENSMP). As a first step, the coupled model (called in the following CIRSE) uses prescribed atmospheric forcing deduced from meteorological analysis. Several high resolution databases on a fourteen-year period have been constituted. The first part of the article presents the meteorological forcing database, the discharges database and the soil and vegetation maps. Then, the first results of CIRSE model and its validation on the riverflows are shown. As the coupled model was proved to be able to simulate present hydrology characteristics, it was finally used to conduct a preliminary climate change impact study. The impact of surface air temperature and precipitation variations on the hydrological cycle in a doubling CO2scenario simulated by the Meteo-France climate General Circulation Model (GCM) are shown.

The oviposition of the European grapevine moth (EGVM)Lobesia botranacan be deterred by an extract of conspecific eggs corresponding to 20 egg equivalents. The reduction of the oviposition behavior is dose-dependent. Nine chemicals have been extracted from the eggs and identified as straight chain fatty acids and esters of fatty acids. A mixture of these rather simple molecules induces the same levels of deterrence as the total extract. It might be possible to use oviposition regulating pheromone in the future for the control of EGVM populations.