Monitoring and registering of grassland and fallow fields with multitemporal ERS data within a district of lower Saxony, Germany

The possibilities of monitoring agrarian land use by means of radar remote sensing (ERS/JERS) were analyzed for the district of Goettingen. The investigations were carried out under consideration of the European set aside program. First approaches in 1995 led to the differentiation of six main classes of agricultural land cover representing the major crops of intensive and extensive land use in the respective region. The main emphasis of further observations was put on the monitoring and operational registering of extensively used arable land with radar remote sensing. The first results of the investigation period of 1995 showed two classes of extensive land use, namely “permanent grassland” and “fallow fields”. Further research within an enlarged observation period (1995/96) was aimed at a more detailed view of extensive land use by radar remote sensing and resulted in the extraction of two new main classes of extensive land use, “permanently covered” and “temporarily covered” that could be subdivided according to the degree of surface coverage for each data take. A second approach to enhance the results of the temporal analysis and to explain the backscattering behaviour of extensive agrarian land use implemented a correlation analysis based on the detailed ground truth. The results showed a dominating influence of plant parameters described by the dielectric constant (e.g. water content, biomass). A classification of the land use was carried out to validate the results of the backscatter-analysis and to generate a digital map of land use for the district of Goettingen that can be used as additional input for the agricultural statistics on a regional level