9-71 Nov. 1999 
  
| species, which yields 
ter fits the needs of forest 
1 several aspects and up to 
e. It may well be that laser 
iques of forestry, especially 
; in mountainous countries 
1ess of the dangers of large 
lere is a tendency towards 
rticular trees from time to 
nber volume of such stands 
"asurements. 
ric stands" are delineated 
photographs in order to 
of different tree species, 
can later be used to find out 
Ss. 
AND DATA 
sed the eastern part of the 
'nces research forest, 60 km 
of interest covers about 10 
ly with elevations between 
ige hillslope is 34 percent, 
following data are available 
ight, species, breast height 
lex measurements, etc.) for 
ummer flights with first and 
respectively, and a winter 
pulse recorded. The system 
th ground resolution of 10- 
meters across. Approx. 340 
» 
ifrared imagery from both 
> 1:10,000); 
survey during the winter of 
| points and data from more 
typical for Central Europe: 
s and deciduous trees with 
but less important, fir, oak, 
er of other deciduous trees. 
rch provide only geometric 
three coordinates, X, y, Z are 
is collected. Therefore only 
racted; however, there is à 
c) stand parameters and 
International Archives of Photogrammetry and Remote Sensing, Vol 32, Part 3W14, La Jolla, CA, 9-11 Nov. 1999 
    
   
  
  
  
  
  
  
  
   
    
  
  
  
  
  
  
  
  
  
  
  
   
  
  
Figure 1 Digital ortho image (infrared) of the central part of the research forest. 
4 CHARACTERISTICS OF LASER DATA 
4.1 Laser patterns of geometrically homogenous stands 
The main "geometric characteristics" of forest stands that will be 
dealt with are 
e mean stand height; 
® tree species, grouped to deciduous / coniferous trees; 
e proportion of basal area for coniferous trees; 
e proportion of crown coverage for coniferous trees. 
Within the region of interest, 50 areas with geometrically 
homogenous vegetation of different types and ages, were chosen 
and their boundaries digitized. These sites are used to determine 
main characteristics of different tree species and size and to 
estimate crown coverage of conifers. Angle count samples were 
used to estimate stand heights and basal area proportions of 
conifers. 
  
Figure 2 Perspective view of the laser dots for a mature beech stand. Signal: Summer first pulse. In the lower part the ground hits 
show the lines of flying strips. The "point clouds" in the upper part are crown zones of the trees. Gray corresponds to differing 
heights (original image was colored; dark areas are at the ground level and close to the peaks). 
195