Are landscape complexity and farm specialisation related to land-use intensity of annual crop fields?

摘要

Little is known about the predictive value of landscape complexity and farm specialisation for land-use intensity, although this is critical for regional agri-environmental schemes and conservation of biodiversity. Here, we analysed land-use intensity of annual crop fields of 30 farms in northern Germany that were located in 15 landscapes differing in structural complexity ranging from <15% to >65% non-crop habitats. The proportion of arable land per landscape was used as simple predictor of landscape complexity due to its close correlation with habitat-type diversity, and the proportion of arable land per farm acted as an indicator for farm specialisation due to its negative correlation with stock farming. Land-use intensity was quantified using questionnaires. Landscape complexity and farm specialisation were related to several but not all indicators of land-use intensity. Structurally simple landscapes were related to more nitrogen input and higher crop yields, and farms specialised on annual crops had reduced crop-species diversity, larger fields, higher crop yields and more pathogen species. In contrast to general expectations, pesticide use in annual crop fields was exceptionally high and not a function of landscape complexity or farm specialisation. Our results show that generalizations such as "farms specialised on annual crops and structurally simple landscapes show increased land-use intensity" may be misleading.