OZCAR-RI ORACLE/BVRE Orgeval - France

The creation of the ORACLE / BVRE Orgeval Research Observatory grouping together the watersheds of Orgeval, Grand Morin and Petit Morin, enables the study and understanding of the hydrological and biogeochemical functioning of anthropized rural areas, mainly sedimentary. The joint efforts of Irstea for more than 50 years and all of its partners have made it possible to set up and maintain this system of long-term observation of the environment. This system is now used to (i) identify the processes responsible for water and pollutant transfers at different scales, (ii) the establishment of hydrological and biogeochemical balances at the watershed scale, (iii) Term monitoring of the periodicity and stationarity of these assessments with regard to climate and anthropogenic changes as well as their ecosystem impact. The ORACLE / BVRE Orgeval research observatory is also an essential tool for reflection on environmental observation strategies, both for research questions and for operational objectives. Thus, the scientific project of the Observatory revolves around the following three axes:  Multi-scale and multi-parameter monitoring for the study of processes and the establishment of hydrological and biogeochemical balances (diffuse pollution) at the watershed scale;  Long-term monitoring to assess the periodicity and stationarity of the assessments in the light of global changes and their ecosystemic implications;  Measurement strategies and reflection on the modes of representation of systems: Optimization of data acquisition methods; Assimilation; Optimal representation scale; Conceptualization. The exceptional nature of this system means that it must be sought, on the one hand, for the best possible valuation, and on the other hand for extrapolation and comparison with data and results obtained elsewhere. It also leads to the implementation of multidisciplinary and interdisciplinary approaches to improve knowledge and modeling of the territorial entity that the watershed represents at different spatial and temporal scales. All these operations involve the provision of data, as well as the coordination of research and measurement devices deployed on the ORACLE / BVRE Orgeval Observatory.