BAP-Subproject: Recording and Characterization of Field Margins Using Digital Aerial Photographs

Project Description

Field margins can play an important role in the protection and preservation of the diversity of species in agricultural regions since they provide for example shelter or further food resources in comparison to the agricultural sites. However, the margins can also be affected by plant protection products (PPP) due to drift or overspray which can influence the plant and animal communities.

In Germany, farmers only have to consider field margins during the application of PPP (distance regulations) if the margins are wider than 3 m. Since information about the amount of margins smaller or wider 3 m is scarce, the aim of this project was the recording and characterization of these field boundary structures. Therefore, digital aerial photos of two intensively used agricultural regions (Southern Palatinate (RLP) and East Brandenburg (BB)) were analyzed using Geographic Information Systems. In each region an area of 4.000 ha was examined and the margins were digitalized and described concerning their width, length and area as well as adjoining agricultural sites, adjoining (country) roads and occurrence of hedges.

First analyses of the data have shown that a great proportion of the field margins (RLP ca. 80 % of the length, BB ca. 40 % of the length) were smaller than 3 m (Figure 1). Especially in the area in Southern Palatinate many margins with a width of 1-2 meters could be detected. In the analyzed area of Brandenburg less field margins occurred, since the fields were considerably bigger. Overall, a great percentage of the margins in BB was smaller than 1 m.

Figure 1: Length of field margins in different width-categories. Analysis of two agricultural areas (each 4.000 ha, in Rhineland palatinate (RLP) and Brandenburg (BB)) using digital aerial photos.

 

    These and some further results were shown during an oral presentation at the 4th joint Annual Meeting of the SETAC GLB and the GDCh (Section Environmental chemistry and Ecotoxicology) in 2010. 

    • Hahn, M., Lenhardt, P., Vollmar, T., Brühl, C. A. (2010): Erfassung der Breiten von Saumstrukturen landwirtschaftlicher Flächen auf digitalen Orthophotos (DOPs). Oral presentation at the 4th joint Annual Meeting of the SETAC GLB and the GDCh (Section Environmental chemistry and Ecotoxicology) 2010, Dessau, Germany.