Ecological focus areas - crucial for biodiversity in the agricultural landscape! : position of the German Federal Agency for Nature Conservation (BfN), the German Federal Environment Agency (UBA) and the Agriculture Commission at the German Federal Environment Agency (KLU) on the issue of the national implementation of ecological focus areas / German Federal Environment Agency (Umweltbundesamt), Federal Agency for Nature Conservation (Bundesamt für Naturschutz) ; authors: German Federal Environment Agency (Umweltbundesamt): Knut Ehlers, Dietrich Schulz, Frederike Balzer, Jörn Wogram, Thomas Holzmann; German Federal Agency for Nature Conservation (Bundesamt für Naturschutz): Andreas Kärcher, Nadine Becker, Manfred Klein, Andreas Krug, Beate Jessel