Question: How do functional types respond to contrasting levels of herbage use in temperate and fertile grasslands?
Location: Central France (3°1′ E, 45°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 nor grazing-tolerant, but strongly competitive for light.
Nomenclature: Tutin et al. (1993).
Abbreviations: BE = Beginning of flowering period; DI = Digestibility; IT = Height at top of inflorescence; LA = Individual leaf area; LCC = Leaf carbon concentration; LDM = Leaf dry mass; LDMC = Leaf dry matter content; LFM = Leaf lamina fresh mass; LNC = Leaf nitrogen concentration; ME = Flowering plant height, highest leaf elongated; MH = Flowering plant height, highest leaf not elongated; NG = Number of growing green leaves; NM = Number of mature green leaves; PRT = Plant functional response type; RA = Leaf:Shoot dry matter ratio; SLAF = Specific leaf area (fresh mass based); SLAD = Specific leaf area (dry mass based); SM = Seed mass.