Seed bank build-up in small disturbances in a Mediterranean pasture: the contribution of endozoochorous dispersal by rabbits

The importance of endozoochorous dispersal in seed bank build-up is analyzed in artificial 40 x 40 cm disturbances in a Mediterranean pasture The top 10 cm of soil in the disturbances was replaced by sterile soil, and the excrement laid m half of them was removed fortnightly The seed banks of the disturbances subjected to the two treatments was quantified by germination of soil samples (n = 44) gathered at the start of the following growth season Rabbit droppings were collected fortnightly to quantify their seed content and the pasture seed production was estimated Seed bank regeneration takes place early in the disturbances The main source of qualitative variation in seed banks is their position on the slope, while endozoochory lacks a characteristic qualitative effect However, endozoochorous dispersal is responsible for a significant increase in the number of germinable seeds, the richness and diversity of the seed bank samples with respect to those lacking it The importance of endozoochorous dispersal by rabbits in grassland dynamics is suggested to be its effect on the colonization of small disturbances, where species dispersed with dung are found to be favoured This aids the maintenance of grazing-tolerant communities