Merging SPOT for Landscape-Ecological Studies, Applied to a Coastal Dune Environment
Keywords:Remote sensing, coastal dune, vegetation mapping, evapotranspiration.
The use of satellite remote sensing in landscape-ecological studies has been limited until now by the generally unfavourable spatial and spectral resolutions of the sensors. A concise overview is given of current and future developments in the SPOT and Landsat programs that may be of interest for coastal researchers concerned with mapping of natural vegetation and landscape elements at a sub-regional scale. A method is described in which optimum use is made of the combination of multispectral and panchromatic imagery for mapping vegetation structure in a coastal dune in the south-western delta of the Netherlands. Mean evapotranspiration rates taken from the literature for each type of vegetation, were finally used to visualize the spatial variability of evapotranspiration and to estimate groundwater recharge within a coastal dune environment. It is demonstrated that the Radiometric Method for merging SPOT-XS and-PAN can be used not only to improve rectification accuracies, to depict greater cartographic detail and to enhance spatial resolution but also to improve results of a supervised classification in a fine-grained landscape. In the future the merging procedure will be especially useful for processing multispectral and panchromatic data of SPOT5 and Landsat-7.