This project will continue a long-term, large-scale experimental manipulation examining the importance of biotic interactions including predation, interspecific competition and herbivory in a Chilean semiarid community. This project would continue the longest large-scale experimental study of abiotic and biotic factors in the temperate neotropics and would help to understanding the importance of ecological scale, metapopulation dynamics, and abiotic vs. biotic processes in this important but little known system. Due to the long-term nature of this research the effects of biotic variability on community dynamics, via ENSO are being addressed. Experiments include the testing of the importance of "bottom-up" forces on small mammals. Studies of seed rain and granivory, nutrients, mycorrhiza and metapopulation dynamics will also be initiated in this proposed round of research.
