1. Ecosystem Science Division, Department of Environmental Science, Policy and Management; University of California; Berkeley California USA
2. School of Natural Resource Sciences; University of Nebraska; Lincoln Nebraska USA
3. Faculty of Agricultural Sciences; University of British Columbia; Vancouver British Columbia Canada
4. Department of Physical Sciences; University of Helsinki; Helsinki Finland
5. Department of Plant Ecology; University of Bayreuth; Bayreuth Germany
6. Department of Environmental Sciences; University of Virginia; Charlottesville Virginia USA