More biodiversity at less cost
How much biodiversity are the agri-environment scheme money actually buying? That is a general question, which we address by studying one specific agri-environment scheme: the so called KULT scheme. That scheme is aimed at managing cultural landscape elements, such as stonewalls and field islets, both to make the cultural history of the landscape visible and to benefit biodiversity in the seminatural habitats on or near them. In Sweden such landscape elements are often called “small biotopes”. The scheme has been in place in slightly different versions since 1996, and our field studies spanned 2008 to 2011.
Our studies have been done in a landscape design across three agricultural regions in Scania. We selected half our study landscapes (2.5 by 2.5 km) in areas with high uptake of the KULT scheme, and half in areas with low uptake. In these landscapes we made surveys of vascular plants, pollinating insects (bees, bumblebees, and hoverflies), and birds.
The hypotheses we are investigating are if the prescribed management of the small biotopes are to the benefit or detriment of biodiversity. If joining the scheme farmers are required to remove “overgrowth vegetation”, such as shrubs and most trees. They are not, however, required to mow the herbaceous vegetation. Many small biotopes are also heavily influenced by fertilization, and in some cases even by herbicides and pesticides, from the nearby fields. Because of this it is not clear how the scheme could benefit diversity, at least in the short run.
We are currently in the analysis phase of the project, and expect to be able to present results in a near future.