1. Department of Botany and Microbiology; University of Oklahoma; Norman Oklahoma USA
2. Department of Mathematics; University of Oklahoma; Norman Oklahoma USA
3. Global Carbon Project; International Research Project Office, CSIRO Land and Water; Canberra ACT Australia
4. Department of Plant Biology; University of Illinois; Urbana Illinois USA
5. School of Natural Resources and Environment; University of Michigan; Ann Arbor Michigan USA
6. Department of Biology; Boston University; Boston Massachusetts USA
7. Biology Department and Environmental Studies Program; Bowdoin College; Brunswick Maine USA
8. Nicholas School of the Environment and Earth Sciences; Duke University; Durham North Carolina USA