Effects of climate change on terrestrial ecosystems in Israel: What I have learnt from a long-term experiment?

Understanding the responses of terrestrial ecosystems to global environmental change is a major challenge of current ecological research. Major research efforts are currently being invested to produce reliable scenarios for future plant communities and ecosystem functioning under the uncertainties imposed by climate change. Here, I will present a synthesis of the results obtained so far from a long-term experiment established in 2001, where we implemented rainfall manipulations – irrigation and drought – to dryland plant communities situated along a steep climatic gradient in Israel. This is one of the oldest worldwide rainfall manipulation experiment. Study sites represented arid, semi-arid, Mediterranean and mesic Mediterranean ecosystems, respectively. The climatic scenarios were tested at the semi-arid and Mediterranean ecosystems, while the arid and mesic Mediterranean ecosystems served as controls. Data collected ranged from plant population dynamics to ecosystem function and properties. Additionally, I will present a new experimental rainfall manipulation project testing the effects of changes in rainfall patterns under extreme drought conditions. I will discuss what I have learnt from setting climate change experiments along climatic gradients, its pros and cons, my understanding of key factors regulating ecosystem functioning in our region, opened knowledge gaps and challenges for future studies.