Multiple asynchronous drought facets drive Mediterranean natural and cultivated ecosystems

Area of Science:

• Agro-ecosystem resilience
• Climate variability impacts
• Drought science

Background:

• Drought indices often overlook agro-ecosystem diversity's buffering role.
• Regional climatic variability poses significant agro-environmental threats.

Purpose of the Study:

• Investigate how different drought facets affect agro-ecosystem functioning.
• Determine if drought facet asynchrony prevents multi-crisis events.
• Analyze drought facet synchronization in Lebanon.

Main Methods:

• Employed parsimonious multiple linear regression (MLR) models.
• Examined six yearly drought facets: duration, onset, offset, drying rate, peak drought day, and rainfall pulse intensity.
• Assessed impacts on winter wheat yield, tree-ring radial growth, and wildfire burned areas.

Main Results:

• Delayed drought offset and faster drying rates correlated with increased burned areas (R² = 0.25).
• Drought onset and prior autumn rainfall negatively affected wheat yield (R² = 0.12).
• Tree radial growth response shifted from drought onset to duration with altitude (R² = 0.33).

Conclusions:

• Asynchrony in agro-environmental responses to climate variability buffers against extreme events.
• A compound drought facets index can provide effective agro-environmental climate crisis warnings.