The production of knoweledge is very important in the public policies of biodiversity conservation today. The French ministry of the environment set up a National information system about nature and landscape that aims to face the incomplete character, disparate and uneasy mobilization of the available data on the nature, within the hexagon. The SINP is rather a catalogue and a platform providing the opportunity to give information about who produces data, where it's produced and how and, beyond, to define new stadards to homogenize the data in order to make them cumulative. Our paper will analyse the process to draw up taxonomic references and common methodologies as well as criteria allowing attesting the quality of the data on a national scale. We will them, through a concrete example on a regional scale, address, how the various producers of data, voluntary or professional, agree or disagree to define common rules about the organization, the broadcasting , the property intellectual of the data, etc. We will try to identify who participates in this scheme of collection on the local scale and produces what types of data. More generally, we will explore the legitimacy of the standards established on a national scale, how the combine with the preoccupations of the producers of data on a local scale.