Abstract
Recent studies show that organic farming usually increases diversity, but that the effect varies among organism groups and with landscape context. In mosaic landscapes the effects on diversity are small, while it has larger effects in intensively farmed landscapes. However, one crucial factor - the time since transition from organic to conventional farming - has not been controlled in earlier studies. It is likely that, depending on the traits and dispersal ability of different organisms and on the landscape context, it may take a decade or even more for effects of changes in farming systems to be fully manifested. A reliable assessment of the long-term effects of farming systems like organic farming on biodiversity and ecosystem services thus requires knowledge of both the speed and magnitude of changes in diversity and species composition in different landscapes. Building on our previous (Formas-funded) and ongoing projects, we will examine this problem based on recent developments in metacommunity and landscape ecology. We will examine plants, soil animals, predatory insects, pollinators and two ecosystem services along a time-since-transition gradient crossed with the large-scale gradient in landscapes established in our previous projects. We will also arrange a workshop with Swedish stakeholders on organic farming in the next EU-CAP. The project is of great importance for understanding long-term effects of organic farming and landscape change on biodiversity.
Sweden