Organic landuse on Ritzerau Manor, Subproject: Biodiversity

pictureIn this subproject, since 2001 the changes in the species richness and diversity are investigated during the change from conventional to organic landuse on Ritzerau Manor using ground beetles and rove beetles. On more than 160 sampling sites that are scattered in a grid matrix over the total area, the species are recorded during the whole year by pitfall traps.

The rove beetles that are usually good flyers react distinctly faster on the landuse change than the ground beetles. At the beginning of the landuse change, a significant depression of species richness of ground beetles was determined in the field centres. In a distance of 30 m from the field margins, the species richness already decreased. The extension of the diversity depression depended from the field area: the more distant from the field margin, the deeper the diversity depression.picture

Thus, conventional fields have the function of barriers to the species of the surrounding landscape. After the change of landuse the biodiversity depression successively diminished beginning from the field margin and disappeared after about 4 years. This process shows that organic fields are more permeable for animals and effect not as barriers as do conventional fields.