1. Warnell School of Forestry and Natural Resources; University of Georgia; Athens GA 30602 USA
2. Department of Earth, Atmospheric, and Planetary Sciences; Purdue University; West Lafayette IN 47907 USA
3. Department of Earth System Science; University of California Irvine; Irvine CA 92697 USA
4. Savannah River Ecology Laboratory; University of Georgia; Aiken SC 29802 USA
5. Department of Agronomy; Purdue University; West Lafayette IN 47907 USA