Nature protection in agricultural landscapes by setting aside unproductive areas and ecotones within arable fields (“Infield Nature Protection Spots”)

Sustainable agriculture must meet ecological challenges. European environmental policy is searching for approaches which achieve the nature conservation goals very efficiently (European Commission 1999). Infield Nature Protection Spots (INPS) is an approach which changes land use on specific parts of crop fields by using set aside which is compulsory in the EU (European Commission 1999). Areas with extreme conditions (e.g. of soil moisture or soil fertility) and parts of fields adjacent to biotopes (wood edges, pond edges) are selected for conversion into nature conservation spots. These areas often are characterised by a high habitat potential for wildlife (Kretschmer et al. 1995). This research project has studied the effects of conservation-oriented set aside on economic and ecological issues. Studies of Skylark Alauda arvensis L. show the importance of infield spots as breeding habitats. Alauda arvensis breeding density in cropped areas ranged from 0.20 to 0.65 pairs per ha, compared with 0.90 to 1.10 per ha for areas of set aside during the same period. This result was believed to be related to the relatively open and heterogeneous vegetation structure of the set aside. Open areas adjoining wood lots provide feeding habitats for Great grey shrike Lanius excubitor L., while wet areas within cropped fields provide summer habitats for amphibians when damaging agricultural operations cease. The habitat of a population of Common tree frog Hyla arborea L. was improved by establishing set aside strips along ponds, which are located within crop fields. Four years after establishing strips, the number of individuals “exploded” in 2001. scussed case studies show that specific land use changes which are focussed on important habitat parameters (key factors) may lead to a real improvement for wildlife in arable landscapes. Only a little loss of productive arable land, often combined without any economic disadvantages for farmers, occur. Hence, INPS is an approach which conserves the biodiversity of agricultural landscapes very efficiently.