The Sevilleta National Wildlife Refuge in New Mexico is a 100,000 ha transitional area including Great Basin, Great Plains, Chihuahuan Desert and Mogollon conifer woodland biomes. Steep climatological, elevational, and edaphic gradients within the site regulate biotic responses which, in turn, are mediated by threshold effects of resource availability. Consequently, the Sevilleta is ideal for studies of biotic responses to climatic fluctuation. This project will support research aimed at achieving predictability of ecological change in time and space by using experimentation and advanced technology (e.g., remote sensing, geographical information systems, LIDAR, FTIR). Results will enhance ecological knowledge about; 1) complex processes contribution to spatial patterning at the 1-30,000 m scales, 2) biotic responses differing among neighboring ecosystem types, 3) how climatological events originating in the Pacific Ocean modify local semiarid systems, and 4) the modifying role of animals in population and ecosystem responses to fluctuating abiotic conditions. Emphasis is on change in heterogeneous systems and the attendant considerations of nonlinearity, threshold effects, time lags, and the strongly scale-dependent aspects of regulatory factors. In terms of its fundamental worth and meaning the results from the project should be important additions to the body of ecological knowledge and theory as well as to the better management of natural resources and the resolution of global- scale ecological concerns, for example climate change. A major strength of the project is the scientific group's aggressive attitude toward identifying, testing, adapting, and utilizing newly available technologies in an ecological research context. This approach should not only provide a productive base within the project but also foster on impetus across the entire national network of Long-Term Ecological Research (LTER) projects. The research team is excellent, drawing from three academic institutions, and enjoys the cooperation of the U.S. Fish and Wildlife Service (DOI) who are the stewards for the Sevilleta site. Institutional facilities are quite good with major additions and improvements planned. In all, the conditions for productive pursuit of this research are highly conducive. The Ecosystem Studies Program recommends strongly that six years of funding be committed to this worthwhile addition to the LTER network of projects.
