Subterranean ecosytems - vertical dimensions of conservation

The vertical dimension of conservation: A cost-effective plan to incorporate subterranean ecosystems in post-2020 biodiversity and climate change agendas (DarCo) Subterranean ecosystems host a broad diversity of specialized and endemic organisms that account for a unique fraction of the global taxonomic, phylogenetic, and functional diversity. Furthermore, they deliver crucial natures contributions (i.e. ecosystem services) to peopleespecially the provisioning of potable water to more than half of the worlds population. Yet, out-of-sight subterranean ecosystems are systematically overlooked in post-2020 biodiversity and climate change targets. Only 6.9% of known subterranean ecosystems overlap with the global network of protected areas, with just a few of these areas designed to account for their vertical dimension. Still, subterranean biodiversity patterns remain largely unmapped, even in areas with a long speleological tradition such as Europe. Moreover, we lack a mechanistic understanding of subterranean species` response to human-induced perturbations. The project DarCo aims to map subterranean biodiversity patterns across Europe and develop a concrete plan to incorporate subterranean ecosystems in the European Union (EU) Biodiversity Strategy for 2030. In a multidisciplinary team of leading European scientists in subterranean biology and conservation science, the project will target the acquisition and organization of biodiversity data on subterranean fauna. These data will serve to predict species responses to human threats using Hierarchical Modelling of Species Communities. We further intend a spatial mapping of species response to threats, and by intersecting maps of diversity patterns, threats, and protected areas, we will design a plan to protect subterranean biodiversity complementing the current EU network of protected areas (Natura 2000). Finally, we seek to raise societal awareness about subterranean ecosystems and invite stakeholders to incorporate subterranean biodiversity in multilateral agreements. All data will be made open and re- usable by development of a centralized and open database on subterranean lifethe Subterranean Biodiversity Platform. Keywords: Subterranean fauna, biodiversity, conservation biology, protection strategies, Natura 2000, groundwater ecology, biospeleology