Valuing knowledge on temporal dynamics from long-term monitored basins for neighbouring sites

Abstract

Long-term monitored stations are important investments (of time, money and labour) which enable the evaluation of hydrological responses over the years. An example is the Coët-Dan basin near the city of Naizin (ORE AgrHys, Brittany, France) which has been instrumented since 1992 by INRA, www6.inra.fr/ore_agrhys_eng/. The project is focused on multi-scale temporal variation of water and solute transfers under the effects of agriculture and climate. The knowledge produced has improved our understanding of hydrological processes (Aubert et al. 2013), but such stations can also be directly useful to comprehend the water security issues of surrounding basins, thus tackling the challenges of both Panta Rhei and PUB (Hrachowitz et al. 2013, Montanari et al. 2013. GENERALIZING HYDROLOGICAL KNOWLEDGE TO SURROUNDING BASINSWe propose to apply a methodology which enables the transposition of hydrographs measured in gauged stations to ungauged stations. The gauged station is the long-term monitored basin of the Coët-Dan River and is used to simulate the hydrographs of five surrounding basins of the Blavet and the Oust rivers (Fig. 1). The hydrograph transposition follows three main steps (Fig. 2).