The three main research questions are:

- What is the separate and the combined influence of heat and drought extremes on grassland communities, and how do the responses differ seasonally?
- How do plants respond to a climate with multiple periods of exceptional heat and/or drought in the same year, and how important is the time (recovery period) between such repeated extremes?
- How important are the plants' interactions with its neighbours (con- or interspecific) in stress responses, and how do competitive interactions change because of extremes?