8
severe damaged
0
damaged
Stand 24 (A) □
healthy/slightly
Stand 20 (B)
Stand 16 (C)
damaged
Fig.(3): showing classification results
from different data acquisition methods
of same stand:
1: results of visual interpretation of
CIR photographs .
2: Airborne multispectral scanner
acquired from 1000m altitude above ground
3: Airborne multispectral scanner
acquired from 3000m altitude above ground
4: Landsat-TM from 19S5.
5: Landsat-TM from 1986.
also been counted in each stand also
according to different damage levels, and
respective numbers in percentage have
been calculated. Both percentages have
been set off against and compared with
each other. Fig.(3) Contains the results
of of CIR photo interpretation, Airborne
multi spectral scanner and the results of
2 landsat-TM acquired at Sept.13. 1985
and June 27. 1986. Fig. (3) also shows
the development of the percentage of the
damage level from 1985 to 1936 for three
stands. All the data set (CIR photo
graphs, Airborne multispectral scanner
and landsat-TM 1935) have been acquired
approximately in the same time during the
summer in 1985.
As far as the test site at Erzgebirge is
concerned it was not possible to carry
out a verification and analysis of the
results obtained from landsat images on
the same method such as the test sit--, at
St.Blasien., due to the lack of field
and/or CIR photographs. The user deter
mined a certaine damage levels especially
for this test site (see ch.2). The main
verification methodology of the results
was the comparison with the interpreta
tion of infra red color composit from the
original data.
Results of supervised classification are
shown in photo (4 and 5).
To estimate the forst decline development
between 1976 and 1985, results of the
evaluations have been taken as a basis
for the calculation. A part of the test
site Erzgebirge has been delinated by a
poligon on classified images of 1976 and
1935. The area covers about 51.717 ha.
And is estimated by pixel number and
pixel size.
All the classified pixel in this poligon
on the results of 1976 and 1935 have been
counted according to the damage levels.
(Tab.2) gives information about the
situation of the forest area changing
between above mentioned period.
Damage Landsat
Level MSS
26.06.1976
healthy/ 8 Ga
slight ly
sever ely
dead forest
and clear 20%
cut area
Landsat
TM
30.09.1985
48%
52%
Tab. 2: Forest damage development- in the
period 1976-1935.
431