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res can be ascribed to other use. In particular the so-
called rest holes belong to the last category of areas
which resulted from huge mass deficits by coal extraction
and excavation technology. The re-increase of ground
water table has filled up the holes. The lateral zones of
the rest holes, and especially those ones of the hole F
(Fig. 4), where sedimentation processes are still under
way, have been selected and preserved, beside others,
as natural succession areas. Another reason for this
decision is the fact, that these rest holes can not be used
for recreation purposes. Similar renaturation areas were
also selected in the southern part of the opencast mine.
As the closure of the mine took place only in 1991, the
natural succession in this part have begun substantially
later. According to the above mentioned goal of efficient
environment monitoring for renaturation processes in
post mining landscapes, appropriate test areas were
selected in the rest hole peripheral zones after botanic
viewpoints. These areas can be described as so-called
pioneer settling communities in the form of:
- silver grass-festuco-brometea
- grass and herbaceous plants
- reed areas and
- dumps covered with dense moss.
An aerial photograph taken in June 1995 confirmed the
assumption made in preparatory investigations, that the
vegetation categories could be differentiated by CIR ima-
gery. As no high spatial resolution satellite photographs
from the cameras KFA-1000 respectively KWR-1000
0.5 0
were available in 1995, aerial photographs were used to
simulate suitable data sets with a spatial resolution of
2m. For comparing purposes merged panchromatic and
multispectral SPOT data with a final resolution of 10m
were investigated (Fig. 4). It was demonstrated, that in
case of the high resolution satellite data four categories
of vegetation could still be discerned. The SPOT data
set, on the other hand, permitted only a discrimination
between vegetation and uncovered soil without being
able to further differentiate single vegetation categories.
Matching the interpretation results for succession areas
obtained by the simulated satellite data with a ground
truth botanic survey, more detailed parameters can be
derived for the running renaturation process.
4 RECULTIVATION PROCESSES
Determination and supervision of recultivation processes
of opencast mine dumps require in particular the
observation of vegetation development. Depending on
dump soil quality, which is linked to the soil material
deposited by a special conveying bridge, and the follow-
up measures aimed at physico-chemical soil
amelioration, the dump areas are prepared for
agricultural and forestal usage or for landscaping
measures (wetland habitats, slope stabilization) as well.
For monitoring recultivation processes it is necessary to
determine the object category of the areas, their state
0.5 km
Fig. 4. Comparision between high spatial resolution satellite data for the determination of succession areas in the
region of Schlabendorf, left: simulated KWR 1000, resolution 2m, right: SPOT XP-*XS, resolution 10m
771
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B7. Vienna 1996