The aims of our work were therefore to investigate and compare in the same experiment the relative influences of the main factors thought to drive Microcystis benthic recruitment, namely temperature, light level and sediment mixing, to find out whether a prolonged phase of benthic life could affect the recruitment rate. We therefore compared the recruitment of two benthic populations of Microcystis sampled in the Grangent reservoir in sediment layers of different ages: a newly sediment population, the same population at the end of the overwinter phase, and a third population which had sediment almost 3 years ago.