Vole mound effects and disturbance rate in a mediterranean plant community under different grazing and irrigation regimes

摘要: A factorial field experiment was used to assess the influence of soil-disturber mammals in structure a 9-year-old Mediterranean annual plant community subjected different sheep grazing and irrigation regimes. We estimated disturbance rate (mound building activity) by voles, their effects on vegetation mechanisms these during period vole outbreak. The were analysed at levels species, functional groups community. Disturbance high voles can disturb entire soil surface once every four or five years. availability certain trophic resources (perennial plants) appeared drive expansion experimental plots it independent treatments. Mound activities largely affected but conserved plot differences. Total cover, absolute cover all groups, mean height species richness less mounds than undisturbed ground. These did not change relative abundance annuals, perennials, grasses forbs. Only small-seeded decreased mounds. As proportion seeds similar both types patches, we suggest that had more difficulties for germinating emerging when they are buried mound formation. Irrigation promoted large changes parameters were, general, Our results show germinable may be major limitation revegetation, probably due scarcity existing depths from which soils excavated. also suggested resource provide additional evidence disturbances small herbivore exert relevant ecological abandoned croplands. discuss implications mound-building succession, conservation forage livestock.