OOS 12 - Consequences of Future Climate Variability On Productivity, Carbon Storage, and Water Balance In Arid and Semiarid Regions

Tuesday, August 7, 2012: 8:00 AM-11:30 AM
B110, Oregon Convention Center
Daniel R. Schlaepfer, University of Basel
William K. Lauenroth, University of Wyoming; and John B. Bradford, U.S. Geological Survey
Ingrid C. Burke, University of Wyoming
Future climate scenarios predict increased climatic variability such as more intense heat waves, longer dry spells, and bigger storms. Ecological research on climate change impacts typically focuses on means and often neglects the consequences of more frequent extreme events. Particularly in regions where climatic conditions are often limiting factors, such as water availability in arid and semiarid ecosystems, increased variability in weather events may result in novel spatial and temporal dynamics of water balance to which ecosystem productivity, species composition, and carbon storage may respond in nonlinear ways. Consequently, understanding trajectories and thresholds of ecosystem responses to climatic variability will be important for effective land management. For instance, an increase in the frequency of more intense and earlier summer dry periods in the intermountain region may shift the seasonal water balance from storage-dominated to pulse-dominated – a change that would likely shift vegetation dominance from woody species to grasses. This session will include speakers from grassland, shrubland, and semi-arid forested systems, as well as speakers that focus on ecotone dynamics between these systems. Speakers will address the consequences of climate variability for a wide range of ecosystem processes for which temporal historical records and/or future predictions are available. Talks will be organized in groups starting with ecosystem water balance as an intermediary between climate variability and ecosystem functioning, followed with talks addressing vegetation composition, and third with talks examining impacts on ecosystem productivity and carbon balance consequences. Comparing and contrasting results across biomes and across different aspects of climate variability may lead to further synthesis products. This session aims to review ongoing research and to provide a roadmap for future research to improve our understanding of how to manage arid and semiarid ecosystems under increased frequency of extreme events.
8:00 AM
 Soil water dynamics and ecosystem water balance in the semiarid West
William K. Lauenroth, University of Wyoming; Daniel R. Schlaepfer, University of Basel; John B. Bradford, U.S. Geological Survey
8:40 AM
 Weather variability in semiarid ecosystems: Consequences for ecosystem water balance and soil water availability
John B. Bradford, U.S. Geological Survey; Daniel R. Schlaepfer, University of Basel; William K. Lauenroth, University of Wyoming
9:00 AM
 Resilience of semi-arid forests to precipitation patterns: Lessons learned from a dry forest in Israel and a ground-water controlled forest in California
Naama Raz-Yaseef, UC Berkeley; Dennis D. Baldocchi, University of California; Dan Yakir, Weizmann Institute of Science
9:20 AM
 Future regeneration of big sagebrush under climate variability
Daniel R. Schlaepfer, University of Basel; William K. Lauenroth, University of Wyoming; John B. Bradford, U.S. Geological Survey
9:40 AM
9:50 AM
 Effects of interannual precipitation variability on ecosystem water balance and its consequences for aboveground net primary production
Osvaldo E. Sala, Arizona State University; Laureano A. Gherardi, Arizona State University; Debra Peters, USDA Agricultural Research Service
10:10 AM Cancelled
 The inertia of C gains in grasslands and shrublands of South America: Changes across environmental gradients
José Paruelo, Universidad de Buenos Aires and CONICET; Marcos Texeira, Universidad de Buenos Aires and CONICET
10:30 AM
 Climate change and the carbon cycle: A view from arid-semiarid grassland ecosystems
Michell L. Thomey, University of New Mexico; Scott L. Collins, University of New Mexico
10:50 AM
 Desert plant demography and climate change: more variable is not bad
Roberto Salguero-Gomez, The University of Queensland; Wolfgang Siewert, Tubingen University; Brenda Casper, University of Pennsylvania; Katja Tielbörger, University of Tuebingen
11:10 AM
 Exotic grass invasion in western US deserts alters landscape scale responses to precipitation and temperature through fire
Kevin J. Horn, Brigham Young Univiersity; Ryan R. Jensen, Brigham Young University; Samuel B. St. Clair, Brigham Young University
See more of: Organized Oral Session