A primary objective of the Jornada Basin research program has been to provide a broad view of arid land ecology. Architects of the program, more recently scientists with the Jornada Basin Long-Term Ecological Research (LTER) program, felt that existing ecological data sets were usually of too short a duration and represented too few ecosystem components to provide a foundation for predicting dynamics in response to disturbances (NSF 1979). This recognition gave rise to the approach of using long-term and multidisciplinary research at particular places to advance a holistic and broad-scale but also mechanistic view of ecological dynamics. Such a view is essential to applying ecological research to natural resources management (Golley 1993; Li 2000). In this synthesis chapter we ask: What has this approach taught us about the structure and function of an arid ecosystem? How should this knowledge change the way we manage arid ecosystems? What gaps in our knowledge still exist and why? The Jornada Basin LTER was established in 1981 with the primary aim of using ecological science to understand the progressive loss of semiarid grasslands and their replacement with shrublands. This motivation echoed that which initiated the Jornada Experimental Range (JER) 69 years earlier. The combined, century-long body of research offers a unique perspective on several core ideas in ecology, including the existence of equilibria in ecosystems, the role of scale, landscape heterogeneity and historic events in ecosystem processes and trajectories, and the linkage between ecosystem processes and biodiversity. From this perspective, we examine key assumptions of this research tradition, including the value of the ecosystem concept and the ability to extrapolate site-based conclusions across a biome. The Jornada Basin research program is also uncommon in its close ties to long-term, management-oriented research. The research questions first asked by the U.S. Forest Service and later by the Agricultural Research Service (ARS), such as how to manage livestock operations, frame much of the Jornada Basin research. This allows us to consider the contributions of this research and synthesis toward answering management questions.
Ecosystem Processes and Human Influences Regulate Streamflow Response to Climate Change at Long-Term Ecological Research Sites