Analysis and experimentation on ecosystems

Tree species distribution, and hence forest biodiversity, relies on the reproductive capacity of trees, which is currently affected by climate change. Drought-induced pollen sterility could increase as a consequence of more intense and more frequent droughts projected for temperate and Mediterranean regions, and threaten the sexual regeneration of trees in these regions. To evaluate this possibility, we examined the effect of long-term partial rainfall exclusion (À27% precipitation) on male reproductive development in holm oak, Quercus ilex, one of the most important and widespread tree species of the Mediterranean region.