Parameter determination by RapidEye and TerraSAR-X data: A step toward a remote sensing based inventory, monitoring and fast reaction system on forest enterprise level

State forest administrations in Central Europe have to adapt to future climatic and socioeconomic conditions. This results in new demands for up-to-date and precise forest information-especially with regard to the increase of forest damages by natural hazards. Remote Sensing techniques are appropriated for delivering information in support of such tasks. We present details of a research project that focuses on the demonstration of the potential of satellite data for forest management planning and disaster management. Integrated in the over-all concept of a decision support system (DSS) for the forest-wood chain (Entscheidungs-Unterstützungs-System Forst-Holz, EUS-FH), the frame conditions for a "Remote Sensing based Inventory and Monitoring System" for the forest-wood chain are developed. Particular focus is on investigations towards synergistic and complementary use of the two German satellite systems RapidEye and Terra SAR-X. The comparison is done on base of the accuracy of parameter derivation with each of the systems. The results deliver a couple of arguments for combined multispectral and SAR data use for monitoring and fast response situations in case of sudden calamities. But it reveals as well that the references against the results should be compared and, at the end, which represents the data layers to be updated, do not always fit from both, the semantic meaning e.g., the definition of "forest" to cartographic differences, and the representation of object categories. Harmonisation of definitions and categories to be mapped is needed.