Biotic, abiotic and performance aspects of the Nevada Desert Free-Air CO2 Enrichment (FACE) Facility

Arid and semiarid climates comprise roughly 40% of the earth's terrestrial surface. Deserts are predicted to be extremely responsive to global change because they are stressful environments where small absolute changes in wat er availability or use represent large proportional changes. Water and carb on dioxide fluxes are inherently coupled in plant growth. No documented global change has been more substantial or more rapid than th e increase in atmospheric CO2. Free Air CO2 Enrichment (FACE) technology pe rmits manipulation of CO2 in intact communities without altering factors su ch as light intensity or quality, humidity or wind. The Nevada Desert FACE Facility (NDFF) consists of three 491 m(2) plots in the Mojave Desert recei ving 550 mu L L-1 CO2, and six ambient plots to assess both CO2 and fan eff ects. The shrub community was characterized as a Larrea-Ambrosia-Lycium spe cies complex. Data are reported through 12 months of operation.