OOS 4 - Change On the Edge: Exploring Ecosystem Implications for Altered Climate Drivers When the Plants Are Not Growing

Monday, August 6, 2012: 1:30 PM-5:00 PM
C124, Oregon Convention Center
Seeta A. Sistla, University of California, Santa Barbara
Kate M. Buckeridge, University of California, Santa Barbara
Joshua P. Schimel, University of California, Santa Barbara
Climate change impacts on dormant season biogeochemical processes are largely ignored in ecosystem studies. However, there is growing recognition that ecosystem biogeochemical cycling may be particularly susceptible to changing climatic conditions during plant senescence and through dormancy. Change in the fall-winter-spring biogeochemical conditions may impact primary production during the coming growing season, creating feedbacks between altered seasonal climate signals and ecosystem processes over decadal time scales. The goal of this organized oral session is to explore the effects of climate drivers, during seasonal periods historically overlooked by ecologists, on biogeochemical cycling and its implications for ecosystem feedbacks. Altered precipitation and temperature regimes during periods of plant senescence and dormancy are predicted for many biomes. This session will incorporate studies ranging from desert to tundra ecosystems, and would be of interest to researchers spanning a wide range of research areas, including empiricists and modelers. An important objective of this session is to identify geographical areas where climate changes during the dormant season have had (or not had) discernable effects on growing season biogeochemical dynamics. This OOS will be organized by biome, with type and duration of climate change manipulation nested within the biome category. We anticipate having two to three speakers from each of four biomes: desert/Mediterranean, temperate forest, boreal forest and tundra (alpine and/or Arctic), representing both short- and long-term perturbations, including empirical studies and mechanistic models. We seek to identify systems that are the most susceptible to climate change during plant dormancy or senescence, and categorize what factors are correlated with systems that are more (or less) vulnerable to these changes. Researchers will be asked to highlight the duration and timing of the climate perturbation(s) they discuss, in an attempt to distinguish resistant ecosystems from those ecosystems that lag between altered soil biogeochemical dynamics and ecosystem feedbacks.
1:30 PM
 Climatic controls on ecosystem resilience: Post-fire regeneration in the Cape Floristic Region of South Africa
Adam M. Wilson, Yale University; John A. Silander, University of Connecticut; Andrew M. Latimer, University of California Davis
1:50 PM
 Biogeochemical response to fire in Mediterranean-type watersheds
Erin J. Hanan, University of California, Santa Barbara; Joshua P. Schimel, University of California, Santa Barbara; Carla D'Antonio, University of California Santa Barbara; Christina Tague, University of Calfornia, Santa Barbara; Dar A. Roberts, University of California at Santa Barbara
2:10 PM
 Climate variation and soil microbial biomass and activity in northern hardwood forests
Jorge DurĂ¡n, Cary Institute of Ecosystem Studies; Jennifer L. Morse, Portland State University; Peter M. Groffman, Cary Institute of Ecosystem Studies
2:30 PM
 Soil freezing perturbation to nitrogen cycling in the northern hardwood forest
Peter M. Groffman, Cary Institute of Ecosystem Studies
3:10 PM
3:20 PM
 Frost damage and winter nitrogen uptake by the grass Poa pratensis: Consequences for vegetative versus reproductive growth
Hugh A. L. Henry, University of Western Ontario; Andrey V. Malyshev, University of Bayreuth
3:40 PM
 Effects of changes in winter snowpack on above- and belowground carbon fluxes in a mixed-hardwood forest
Andrew B. Reinmann, Boston University; Pamela H. Templer, Boston University
4:00 PM
 Shifting carbon dynamics in a warmer world: Increasing respiration from frozen soils
Susan M. Natali, Woods Hole Research Center; Edward A. G. Schuur, University of Florida; Elizabeth E. Webb, University of Florida
4:20 PM
 The influence of spring temperatures and snow depth on arctic tundra plant growth and soil nutrient dynamics
Michael N. Weintraub, University of Toledo; Heidi Steltzer, Fort Lewis College; Patrick F. Sullivan, University of Alaska Anchorage; Joshua P. Schimel, University of California, Santa Barbara; Matthew D. Wallenstein, Colorado State University; Anthony Darrouzet-Nardi, U.S. Geological Survey; Aliza A. Segal, University of Alaska
4:40 PM
 Exploring the consequences of winter versus summer permafrost soil warming using a microbial physiology-explicit decomposition model
Seeta A. Sistla, University of California, Santa Barbara; Edward B. Rastetter, Marine Biological Lab; Joshua P. Schimel, University of California, Santa Barbara
See more of: Organized Oral Session