Sammendrag

Semi-naturlig eng er svært artsrike blomsterenger som representerer viktige kultur- og naturverdier arvet fra våre forfedre. Det høye biologiske mangfoldet i engene er et resultat av generasjoner med ekstensiv jordbruksdrift i form av beite og slått. På grunn av brakklegging og intensivering i jordbruket er denne naturtypen i sterk tilbakegang og vurdert som truet. Det er derfor etablert et overvåkingsprogram som dokumenterer status og identifiserer endringer i økologisk tilstand, biologisk mangfold og arealet av de få og spredte gjenværende semi-naturlige engene i Norge.

Sammendrag

Species-rich natural and semi-natural ecosystems are under threat owing to land use change. To conserve the biodiversity associated with these ecosystems, we must identify and target conservation efforts towards functionally important species and supporting habitats that create connections between remnant patches in the landscape. Here, we use a multi-layer network approach to identify species that connect a metanetwork of plant–bee interactions in remnant semi-natural grasslands which are biodiversity hotspots in European landscapes. We investigate how these landscape connecting species, and their interactions, persist in their proposed supporting habitat, road verges, across a landscape with high human impact. We identify 11 plant taxa and nine bee species that connect semi-natural grassland patches. We find the beta diversity of these connector species to be low across road verges, indicating a poor contribution of these habitats to the landscape-scale diversity in semi-natural grasslands. We also find a significant influence of the surrounding landscape on the beta diversity of connector species and their interactions with implications for landscape-scale management. Conservation actions targeted toward species with key functional roles as connectors of fragmented ecosystems can provide cost-effective management of the diversity and functioning of threatened ecosystems.