Return to Biosphere 2: Mesocosm research and outreach in an era of global change

Background/Question/Methods

The turn of the 21^st century saw an evolution in ecology characterized by greater utilization and acceptance of non-manipulative “observation based” studies.  Some of this shift arose from the limitations of controlled experimental studies to capture the complexity or scales of space and time—particularly as they relate to global change research—that can be addressed in observation-based research.  Additionally, advances in technologies pertinent across scales of biological complexity—from genomics to remote sensing—have afforded observation-based studies much greater power to infer mechanisms underlying ecological phenomena, which is often cited as a severe limitation of non-experimental ecology. Nonetheless, with these new abilities and needs for uncontrolled observational studies come new challenges and questions that simply cannot be addressed in the complex and mostly uncontrollable field arena. A largely unexplored space for ecological research that can address these gaps is the mesocosm, a site that features some of the control of a laboratory (or experimental plot) and some of the complexity and scale of the natural world.  There are a number of outstanding questions­­—related to basic life history, population monitoring, marine pollution, mechanisms controlling biodiversity, and studies of global change—that can be addressed in mesocosms.

Results/Conclusions

Here I discuss the opportunities and challenges ahead for mesocosm research, with a particular focus on marine systems (where this scale is perhaps least utilized). Using the past, present, and future of the University of Arizona’s Biosphere 2’s large marine mesocosm biome as an exemplar, I first provide a framework of six pertinent questions and effective approaches that might be utilized in existing or as yet un-built marine mesocosms. Four major challenges of marine mesocosm research are discussed in the context of manipulative and observational approaches to ecology. Finally, I outline the significant opportunities for community building (within and between institutional scientific communities and the public) afforded by large-scale mesocosms. As I discuss here, mesocosm research can be difficult, costly, and fraught with limitations, but it may nonetheless become a vital link in achieving understanding of our complex and changing ecological systems.