Résumé
Question: How do functional types respond to contrasting levels of herbage use in temperate and fertile grasslands? Location: Central France (3 degrees 1' E, 45 degrees 43' N), 870 m a.s.l. Methods: Community structure and the traits of dominant plant species were evaluated after 12 years of contrasted grazing and mowing regimes in a grazing trial, comparing three levels of herbage use (high, medium and low). Results and Conclusions: Of 22 measured traits (including leaf traits, shoot morphology and composition, phenology), seven were significantly affected by the herbage use treatment. A decline in herbage use reduced individual leaf mass, specific leaf area and shoot digestibility, but increased leaf C and dry matter contents. Plants were taller, produced larger seeds and flowered later under low than high herbage use. Nine plant functional response types were identified by multivariate optimization analysis; they were based on four optimal traits: leaf dry matter content, individual leaf area, mature plant height and time of flowering. In the high-use plots, two short and early flowering types were co-dominant, one competitive. grazing-tolerant and moderately grazing-avoiding, and one grazing-avoiding but not -tolerant. Low-use plots were dominated by one type, neither hardly grazing-avoiding C 0 nor grazing-tolerant, but strongly competitive for light.