MICROHABITAT METHODOLOGY - VALIDATION AND PERSPECTIVES

Instream Flow Incremental Methodology (''microhabitat'' methodology, i n French) is presently the most used tool to evaluate stream carrying capacity by crossing informations from biological and hydraulic models . It is used in negotiation for minimum instream flow determination in regulated rivers. However, the biological validity of the methodology remains its main uncertainty. Hypotheses and experimental conditions for validation are presented and discussed. The discussion of each mod el explains its present development and future research necessary to i mprove the methodology.