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According to the latest IPCC projections, Mediterranean ecosystems show a high vulnerability to climate change, as the projected rainfall reduction is expected to exacerbate water stress during dry seasons. During the past two decades, several climate change manipulative field experiments have been performed in Spain for the understanding of climate change impacts on terrestrial ecosystems. However, individual experiments need to be integrated into systematic networks to better assess the effects of climate change in spatial and temporal gradients. Thanks to the support of the two projects (AnaEE-Sp and Infra23), it was possible to create the first Spanish consortium of climate change manipulative experiments, including 12 experiments and 9 research groups, that will potentially be incorporated in the near future into the European network AnaEE-ERIC. In the framework of this initiative, it was carried out the first coordinated soil sampling in these 12 experiments (5 woodlands, 3 shrublands, 4 agroecosystems) along a latitudinal gradient of Mediterranean ecosystems, allowing the study of rainfall exclusion (median, 30% rainfall reduction for 8 years) on soil properties, respiration rate, and biodiversity, focusing of the effect of drought conditions on bacterial, fungal and nematode communities. We calculated the log response ratio of drought versus control conditions for all variables, and performed generalised linear mixed models including site as a random factor. The simulated drought conditions did not modify surface radiation or soil temperature, while inducing a significant decrease in the relative air humidity and the volumetric soil water content regardless of the land use. Despite generally reducing water availability, drought conditions only marginally diminished CO2 emissions from soils to the atmosphere across land uses. We discuss these results in light of the effects of drought on the composition and diversity of soil microbial communities, contributing to our understanding of microbial responses to climate change in highly vulnerable areas. Additionally, we have identified different potential partners for the AnaEE-Sp network, making a total of 47 climate change manipulative experiments in Spain, of which 39 are still active. Covering a larger climatic and ecosystem diversity gradient, the future collective efforts on the study of climate change effects on terrestrial ecosystems, and the inclusion of some of these infrastructures of AnaEE-Sp in AnaEE-ERIC, will enhance our knowledge on climate change impacts on Mediterranean and European ecosystems.
