'Half Europe’: where and how can biodiversity conservation be achieved in the Anthropocene?

Living in a geological epoch, which is by now referred to as the Anthropocene we are witnessing an unprecedented magnitude of negative effects on both biodiversity and ecosystem services (ES) resulting from human activities. Some of the lead ecologists and environmental scientists of our time have issued several warnings on the state of the earth advocating urgent measures to halt biodiversity loss, like the provocative proposal of conserving half of the Planet. Inspired by the idea that we need more space for biodiversity conservation to reverse the trend of increasing habitat loss, this special issue invited studies that examine the current situation in Europe addressing questions like which are the most important areas for biodiversity and ecosystem services in Europe? What is the level of our knowledge about them? Which are the methods and techniques to identify hotspots of biodiversity and ES today? The EU’s Biodiversity Strategy for 2030 sets a target of 30 % coverage for Protected Areas (PAs), of which 10 % should be strictly protected. Having missed the 2020 deadline, it is now questionable whether we can realistically achieve the targets set by the new EU biodiversity strategy. In addition to identifying important biodiversity and ES areas, there is a need to identify conservation initiatives and practices which consider the natural and social context, to identify the most efficient ones. Thus, additional topics of discussion include the following: Which are the different forms of biodiversity and ecosystem services conservation existing today, and what is their contribution? What can we say about the limitations or advantages of these conservation forms we have been applying? Finally, given that Europe is characterized by high population density and a high degree of urbanization, an important challenge considered is the coexistence of nature conservation with societal needs.