IMEXCLIME

IMpacts of EXtreme CLIMatic Events on ecosystem functioning in alpine grasslands

Keywords: alpine grasslands, climate change, drought, ecosystem processes, erosion, high intensity rainfall

Context

Human induced climate change is unequivocal and ongoing, with the European Alps being a hotspot of warming. The future summer climate in Switzerland is predicted to be drier and warmer, with an increased probability of extreme events such as high intensity rainfall. In this project, we propose to study the impacts of prolonged summer drought and intensive rainfall on key ecosystem processes and services of alpine grasslands.

At three sites in Swiss Central Alps representing the most contrasting extremes in macroclimate and geology we will simulate drought with rainout shelters, combined with a rainfall experiment. Adopting an integrated and process-orientated approach, we propose to study (i) changes in sward structure and productivity, (ii) susceptibility to erosion and surface runoff, (iii) species-specific water stress responses, and (iv) litter decomposition, mineralisation and soil respiration in complementary work packages.

Our project will contribute to predictions of the consequences of the most likely climate change scenario for the Swiss Alps. Because vegetation integrity of alpine grasslands reduces risk of erosion and secures slope stability, knowledge on vulnerability of these grasslands to climate change is crucial for the welfare and safety of many people.