Simulating Climate Future: Long-Term Drought Impacts on Mediterranean Ecosystem Structure and Function

Climate change is profoundly affecting ecosystems globally, increasing the frequency and severity of droughts. The eastern Mediterranean, characterized by high climatic variability and water scarcity, faces critical challenges to biodiversity and ecosystem functionality. This study leverages over two decades of rainfall manipulation experiments at the Matta LTER site in Israel to investigate how Mediterranean ecosystems respond to chronic and extreme drought conditions and altered rainfall patterns.

Experimental treatments included 30% and 66% reductions in annual precipitation, coupled with variations in rainfall distribution, simulated through rainout shelters. Results revealed that the ecosystem demonstrated resistant to moderate drought, with minimal changes in biomass and species diversity under a 30% rainfall reduction. However, extreme drought conditions (66% reduction) significantly impacted aboveground biomass and altered species composition, suggesting the presence of ecological thresholds. The study highlights the importance of soil moisture dynamics, drought-resistant plant traits, and seed bank contributions in maintaining ecosystem functionality under stress.

The findings underline the critical need for long-term monitoring and advanced methodologies, including AI-driven modeling, to identify tipping points and predict ecosystem responses under future climate scenarios. These insights provide valuable guidance for adaptive management strategies to enhance the resilience and sustainability of Mediterranean ecosystems amid accelerating climate change.