1. Theoretical Physics Division, Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg 188300, Russia
2. USDA-China MOST Joint Research Center for AgroEcology and Sustainability, University of California, Riverside 92521-0124, USA
3. Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, Ås, Norway
4. Centro de Ciência do Sistema Terrestre INPE, São José dos Campos, São Paulo, 12227-010, Brazil
5. School of Botany and Zoology, The Australian National University, Canberra, Australia