Leaf and ecosystem response to soil water availability in mountain grasslands

► Climate change is expected to cause more frequent and severe summer droughts in the Alps. ► The sensitivity to soil drying was studied by laboratory leaf and field ecosystem gas exchange measurements. ► Currently occurring dry periods do not substantially affect the investigated grassland. ► The plant species are insensitive to soil drying until extremely low soil water contents. ► Mountain grasslands may contribute to recession in stream flow during droughts.