Comment Low Variability Moderate Variability High Variability
example forest/urban areas/water de- and regeneration stages farmland, meadowland, peatland
strategies determination of a high number | these areas are in most cases for every new classification new training-
of reference areas
digitising and assigning of
attributes (as a vector layer or
gradual stages (e.g. dense areas) and test areas have to be mapped
determination of a high number of
reference areas
area of interest)
Ist vector layer (AOT) can be
used for subsequent classi-
fication
only those areas have to be assessed
no new determination of
training areas are necessary
succession
new training sets have to be found if
areas have changed due to gradual
it is not necessary to map these
classes on the day of data
acquisition
mapping time
the mapping should be close to the
day of data acquisition
the mapping should be on the day of data
acquisition
Table 2: Time Variability of Areas and Strategies
Analyses for the transferability of signatures from one test area
to another bogland within the same scene shows good results.
These results have been inspected by a visual comparison with
actual biotope mappings. The transferability of signatures from
one scene to an other has been tested in the overlapping area of
scenes 196-23, 195-23 and 195-24. It shows that only
signatures with a low time variability (e.g. urban areas, airport)
are transferable. The other signatures should not transferred
because of different sunangles, haze and radiometric
differences.
Results from multisensor analyses with different data fusion
techniques, e.g., principle component and IHS-transformations,
show no significant improvement in the differentiation of
signatures (classes). Classification results from a combination
of Landsat-TM imagery and SPOT-Pan or ERS-1 data indicate
that there is no improvement compared to a classification using
Landsat-TM imagery only. A presentation of the signatures in
ellipsoid form in the important feature spaces (scatter diagram)
confirms these results. It shows strong overlapping areas, that
indicate a poor differentiation of some classes and a visual
inspection shows the same negative results for those classes.
7. CONCLUSION
As final steps, all produced information and GIS layers will be
included into the environmental information system of the
Department of Environment, Lower Saxony (GEOSUM). This
information will be provided to the various State Natural
Protection Agencies. This project will support the meadow-
land and peatland protection programme.
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