During a 5-year survey in the Vaccarès lagoon, a successive period of decrease and increase in water salinity was associated with a decline and progressive recovery of a Z. noltii meadow. A negative correlation between cover index and water depth suggests that light availability was a limiting factor for plant growth over this period. The persistence of turbid water due to the lack of flocculation of suspended sediments may explain the decline of the seagrass meadow over the decrease in salinity.