European gradients of resilience in the face of climate extremes
Extreme weather events and the presence of invasive species are two of the currently most pressures threatening biodiversity, resilience and ecosystem services of semi-natural grasslands and can suddenly drive them beyond thresholds of system integrity. SIGNAL will identify and quantify the role of "species diversity", of "within species diversity" and of "key species such as legumes" acting against those two pressures and for enhancing resilience of grasslands, which are spatially and economically important across Europe. SIGNAL is an innovative pan-European research activity takes science beyond current state of the arts research and results in regionally differentiated policy decision support.
SIGNAL Hypotheses
H 1
Droughts suddenly shift European grasslands across thresholds of functional resilience and reduce ecosystem service provision. Resilience varies across the pan-European precipitation and continentality gradient.
Method: Drought field experiment
H 2
Non-native invasive species are additional pressures for grassland biodiversity and functioning, accelerating major system shifts in the face of extreme weather events. In turn, extreme weather events increase invasibility.
Method: Drought field experiment + Mesocosm experiment
H 3
Biodiversity increases functional resilience in the face of extreme weather events (drought). Key functional traits (i.e. legume) modify community response.
Method: Mesocosm experiment
H 4
Within-species-diversity increases functional resilience in the face of extreme weather events.
Method: Mesocosm experiment
H 5
Mowing technique enhances diversity and consequently resilience against climate extremes.