WETLANDS

177 Hurricane Disturbance and Tropical Tree Species Diversity. 2000. Vandermeer, J., Dept. of Biotogy, University of Michigan, Ann Arbor, MI 48109, jvander@umich.edu; I. Granzow de la Cerda, D. Boucher, I. Perfecto, and Javier J. Ruiz. Science 290(5492):788-791. The so-called intermediate disturbance hypothesis states that very large or small disturbances in tropical forests will not prevent suppression of a tree species--that only intermediate disturbances, such as tree-fall gaps, have this effect. To test this hypothesis, the authors examined whether large disturbances also suppress species. They used studies of post-hurricane forest succession that began in February 1989 to examine the pattern of species accumulation on the Caribbean coast of Nicaragua after the large disturbance caused by Hurricane Joan in 1988. Their analysis shows that the pattern after a hurricane differs from that after a single tree-fall disturbance. They conclude that pioneer trees do not respond well after large disturbances and do not suppress other species like they do following smaller disturbances.