The response of meiofauna to human trampling on coral reefs

Coastal environments are trampled by humans worldwide; however, there are few studies that evaluate the effect of trampling on the meiofauna of hard substrates, and none on meiofauna of reef environments. We investigated the effects of trampling due to tourism on the meiofauna of reef formations on the northeastern coast of Brazil. Samples were taken from five paired stations located in two areas on the reef: an area protected since 2004, and an area open to tourist visits. Trampling caused important changes in the meiofaunal assemblage. The densities of the total meiofauna and of the commonest groups were negatively affected in the trampled area. Among the major groups, Polychaeta proved to be very sensitive to this disturbance. The meiofauna groups showed different response patterns to trampling depending on the species of algae trampled. Reductions in animal densities were partly attributed to the loss of turf biomass and associated sand caused by trampling, and partly to the direct effect of people stepping on the animals. Considering the importance of meiofauna in the food web as well as its biodiversity, these results highlight the possible negative effects of human trampling on the ecological and economic services that coral reefs provide.