They propose to expand an existing LTER research project to a site in Mexico. They will examine the roles of indigenous small mammals as keystone species determining plant species diversity and vegetation structure across the Chihuahuan Desert grassland and shrubland ecosystem. The Sevilleta LTER site is located at the northern biome transition of the Chihuahuan Desert/Great Plains grasslands, while the Jornada LTER site is in the north-central Chihuahuan Desert. They propose to add a new research site, the Mapimi Biosphere Reserve (United Nations Man and Biosphere Program), located in the south-central Chihuahuan Desert. This crmss-site research project will involve university scientists with scientists from the US Department of Interior, Fish and Wildlife Service (Sevilleta National Wildlife Refuge), the US Department of Agriculture, Agricultural Research Service (Jornada Experimental Range), and Mexican scientists (Institute of Ecology, Mapimi Biosphere Reserve). Previous research demonstrates that indigenous small mammals are keystone species in Chihuahuan Desert ecosys tems. Other research demonstrates that many Chihuahuan Desert ecosystems have become desertified as a result of human disturbance, and the persistence of desertified landscapes may result from plant resource use and physical soil processes alone. They will experimentally determine how small mammals affect Chihuahuan Desert ecosystems, and how small mammal influences are affected by short-term and long-term climate change both locally, and regionally across the Chihuahuan Desert. They will also integrate cross-site data management network to centralize and coordinate data management activities for the proposed research project. This data management network will include the addition of a real-time satellite communications link at the remote Mapimi research site in Mexico, to link that site to the existing LTER Network. The respective US LTER sites, and Institute of Ecology in Mexico will continue the Long-Term operation of this study beyond the three years of this requested award.
