FOREST DAMAGE INVENTORY USING LANDSAT IMAGERY 
BY MEANS OF COMPUTER-AIDED CLASSIFICATION 
A. Kadro 
Unversitat Freiburg 
D-78 Freiburg 
FED. REP: of GERMANY 
ISPRS, COM. VII 
Abstract: 
The forest decline at present is a major environmental problem occur ring 
in central and western Europe, due to the air pollution and acid lain. Due 
to the rapid increase in forest area damaged, remote sensing techniques 
have become an important and essential tool for large area forest decline 
inventory. This paper presents the potential application and the advantage 
of Landsat imagery for forest damage assessment and the mapping and moni 
toring the progressive development of damage occurring at sites in the 
Black Forest (South West Germany) and in the Erzgebirge (Mountain) region, 
located between East Germany and Czechoslovakia. For this task, satellite 
imagery (Landsat Thematic Mapper and multispectral Scanner) has been used 
for forest damaged assessment. The evaluation of both types of data, using 
computer-aided, supervised classification, makes it possible to identify 
and quantify a ranged forest damaged classes. Another methodology for the 
evaluation of the Landsat data is the ratioing between important spectral 
bands determind to be useful in discrimination of damage. 
Keywords: Landsat imagery. Forest Damage 
Assessment and Monitoring 
1- Introduction: 
During the last decade, a new type of fo 
rest damage situation has, refered to as 
forest decline, occured in many forest 
regions of West Germany and western 
Europe, independent of site conditions 
and independent of the distance to the 
industrial areas. This forest decline be 
gan very early in the Erzgebirge (moun 
tain region) located between Czechoslova 
kia (CSFR) and East Germany (GDR) . The 
first Conference dealing with forest 
decline in this area was held in 1956 and 
reported details regarding the first fo 
rest damage inventory, the damaged area 
at that time was only 10,000 ha. 
(Excursion prospect 1989 to Erzgebirge 
region). Such kind of forest decline, 
characterized by special damage symptoms, 
was considered to be caused mainly by air 
pollution and acid rain (NiefSlein et al 
1985). The forest soil now has a lower pH 
value than previous measurements and soil 
investigations (Butzke 1981). The degree 
of the forest damages differ between the 
study test site in the Black Forest 
(south west Germany) and the study test 
site Erzgebirge, they are now not 
comparable, due to the fact that the 
situation in the forest area in Erzge 
birge is so severe. This area belongs to 
one of the most heavily damaged forest 
areas in Europe and the world, due to air 
pollution. 
The forest damage symptoms are needle 
loss during the active growth stage, 
often accompanied by discoloration (chlo 
rosis). In some cases there is chlorosis 
in the whole crown, part of the upper 
side of the branches only, or in combina 
tion with needle loss. Later these trees 
become dead. This kind of damage leads, 
especially in case of old firs, to a ty 
pical deformation of the crown, due to 
dying parts of the crown (storks nest). 
In the case of young trees, damage begins 
with yellowing and defoliation and 
results is death in a short time (AFZ 
1984, Hildebrandt and Kadro 1984). 
In Germany and western Europe, the forest 
stand structure is mostly, homogeneous in 
term of age and species composition. 
Therefore the damage symptoms in one 
stand are similar. 
To study the situation of the forest con 
cerning the health and vitality, the com 
mission of the European Community's 
Forest and Silviculture Division de 
termined a forest damage classification 
based on the percentage of needle/leaf 
loss. The damage classes are Tab. (1): 
Class 
Needle/ 
Loss(%) 
Leaf Tree health 
0 
0 
to 10 
healthy 
1 
11 
to 25 
slight damage 
2 
26 
to 60 
medium to serious damage 
3 
61 
to 99 
dying 
4 
100 
dead 
"The presence of chlorosis adds a point 
to the 
damage class rating." 
Table 
1984). 
1 
Damage 
Classification (From AFZ 
425