Fig. 2: Overview of the opencast brown coal mining area of Nochten-Reichwalde (SPOT-XS, band 3, July 7, 1995)
1.1 Study area
The investigation area of Nochten (Fig. 2) is situated in the
south-eastern region of Lower Lusatia close to the Polish
border. This area extents about 40km east-west and about
20km in north-south direction. Mining activities have been
carried out since about 1850, starting with underground
mining. At the beginning of the 20" century the exploitation of
brown coal was performed in opencast mining. starting with
small outcrops which steady increased, and by the application
of modern conveying bridges. The opencast mine of Nochten is
one of the five still active mines out of a total of 17 before (like
Báürwalde in the south-west of the area). First prospecting with
bore holes began in the twenties, field drainage in 1965. The
mine opening took 5 years from 1968 to 1973. Since 1973
brown coal have been produced. The preparation of the
opencast mine of Reichwalde began in the seventies. In a
relative small area there are some opencast mines and currently
a narrow interconnection of mining and post mining landscapes
exists. In the north and the east of the investigation area virgin
landscapes which mainly belong to the so called Muskauer
Heath and to the Upper Lusatian Heath and Pool Area in the
south are situated. The boundary in the north represents the
Muskauer Fold Arc with the city of Weisswasser. The area is
sparsely settled. Forest, agriculture and military activities are
predominant. A field habitat mapping carried out in this area of
about 40 000 hectares identified 28 habitat types. seven of
which are important for nature protection. These are two fen
forest types. berry shrub - pine forest, heath fen, shrub heath
and poor short grass types. For about 1400 habitats there exists
detailed descriptions and assessments regarding the interests of
nature protection. The area structure of all habitats consists of
more than 4000 objects.
2 ANALYSES OF THE VEGETATION STATE
2.1 Data selection and preprocessing
The realisation of a long term monitoring system requires a
continuous data acquisition. Up to now remotely sensed data
have been taken from the area since 1985. Due to the
unfavourable weather conditions of Central Europe an optimal
data selection was not possible. Table 1 shows the acquisition
parameters from seven selected data sets of the Landsat
Thematic Mapper (path 192, frame 24) during the main
vegetation periods from 1985 to 1996.
Table 1: Landsat-TM scenes utilised
No. | Acquisition date Ground visibility
1 03.06.1985 50 km
2 14.08.1988 40 km
3 04.08.1990 40 km
4 09.08.1992 15 km
5 30.07.1994 10 km
6 18.08.1995 30 km
7 22.08.1996 35 km
Geocoding to geographical coordinates -was the first step in
data processing. As reference image a SPOT-XP data set
152 Intemational Archives of Photogrammetry and Remote Sensing. Vol. XXXII, Part 7, Budapest, 1998
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