Hard bottom marine biocoenoses constitute one of the most important and productive ecosystems in the world. The continuous observation of these complex systems is therefore of major international relevance in times of global environmental change. The marine nature reserve of the island of Helgoland is located in the German part of the southern North Sea and comprises a large amount of the species representative for Northern European rocky coasts. The recording of spatial changes of the major intertidal biotopes by remote sensing techniques provides a tool to assess biodiversity change on a high hierarchical level and enables a synoptic view of the system. This complements detailed ground based biodiversity studies which are traditionally restricted in area and serves as basis for decisions, e.g. in coastal zone management, nature preservation, and monitoring of the water quality.In July 2002 and September 2003, two data sets of Heligolands coast were acquired with the hyperspectral push broom sensor ROSIS at about 1m pixel size. The data were radiometrically, atmospherically, and geometrically corrected. Based on ground truth data and detailed spectral analysis, a supervised hierarchical classification scheme was developed to classify the different major biotopes of the intertidal zone which are rather small and often overlap, thus creating a complex spatial picture difficult to resolve. Comparison between the 2002 and 2003 data shows the potential and the limitations of this spectral approach and suggestions for improvement are presented. The difference in results between the hyperspectral classification of the biotopes and a recent ground based biotope mapping will be discussed.
Helmholtz Research Programs > MARCOPOLI (2004-2008) > CO1-Coast in change
Helmholtz Research Programs > MARCOPOLI (2004-2008) > CO2-Coastal diversity - key species and food webs