The following 5 challenges have been selected. Each challenge talk should be max 15 minuts providing time for questions and discussions:

Challenge talk 1
Christian Körner, Universität Basel, CH
Old knowledge - new knowledge.
Why is ecophysiology of water relations out of fashion? Old fashion knowledge is still valid, basic responses for models to build upon and reconstruct. (Confirmed)

Challenge talk 2
Markus Reichstein, Max Planck Institut, GE
Soil: the forgotten mediator of ecosystem's response to climate change
Bridget Emmett, Centre for Ecology & Hydrology, Bangor, UK
Do we understand interactions with other drivers of change (e.g. grazing, N deposition etc) and interaction between growth/N-availability/water use.

Challenge talk 3
Jake Weltzin, University of Tennessee, US
How can we distinguish between the direct and indirect effects of water in these types of projects?
In these experiments, water is not only a driving variable; it is a response variable (which in turn makes it a driving variable).
John Grace, University of Edinburgh, UK
Can climate models really predict the changes in rainfall, or are they so imperfect that we should not believe the predictions?