The Sevilleta LTER is located at the intersection of several aridland ecosystem types. Although it is axiomatic that water is the key limiting resource in aridland ecosystems, most arid land soils are also chronically low in nutrients and organic matter. Resource availability is a function of the frequency and size of precipitation events as well as the time between events. As a consequence, NPP and organic matter decomposition are often decoupled in space and time, and soil nutrient supply rates may limit NPP during periods when soil moisture is sufficient for plant growth. In addition, arid and semiarid ecosystems worldwide are undergoing a state transition from grass- to shrub-dominated communities in response to multiple anthropogenic drivers. This life-form shift has important consequences for evapotranspiration, net primary production, carbon fluxes and biodiversity. Overall, our research program integrates studies on multiple global change drivers and pulse precipitation dynamics to determine how they affect the rate at which this grass- to shrubland transition occurs. This poster presents our conceptual framework and project integration, our model of aridland ecosystem dynamics, and highlights several of our key long-term experiments. Together, our observational and experimental research activities will yield a comprehensive understanding of how key abiotic drivers affect pattern and process in aridland ecosystems.