SWEDISH EXPERIENCES ON FOREST INVENTORY AND LAND USE MAPPING 
BY AUTOMATIC CLASSIFICATION OF DIGITAL MSS DATA FROM LANDSAT 
AND AIRCRAFT 
Leif Wastenson, Department of Physical Geography, University of Stockholm 
Box 6801, S-11386 Stockholm 
Torleiv Orhaug and S Ingvar Akersten, National Defen e Research Institute 
Fack, S-10450 Stockholm 
Introduction 
In 1973, an experiment of computerized forest inventory from Landsat CCT's 
was initiated in cooperation between the National Defense Research Insti- 
tute and the Department of Physical Geography, University of Stockholm. 
The project started with development of a general computer software system, 
including data handling, image manipulation and object identification. Three 
different types of classification algorithms have been programmed: maximum 
likelihood, table look up and non linear mapping. A presentation of the pro- 
gram system is given in the form of a user's guide by Gustafsson and Aker- 
sten (1976). A version of these programs accessable interactively from re- 
mote terminal had just been realized (Wasteson and Akersten, 1978). 
The development of the software system was followed by classification expe- 
riments on forest inventories and land use mapping from Landsat 1 and 2. 
These studies were followed by classification experiments using MSS data 
from aircraft in forest inventories and mapping of vegetation, land use, 
crops and water qualities. With the MSS data from aircraft it has been 
possible to simulate the future geometric resolution in Landsat. The pro- 
jects, which now are in the evaluation phase, have been sponsored by the 
Swedish Board for Space Activity. 
The maximum likelihood algorithm has been used in most of the classification 
experiments, but comparisons have also been done with the other methods. An 
IBM 360/75 has been used and the classification results are presented in 
color images from an ink jet drum plotter. At present the programs run on 
IBM 370/165, which is about 2.5 times faster. A hard copy of 28 cm x 19 cm 
is made in a few minutes. A description of the ink jet plotter used for dis- 
playing multispectral images has been given by Hertz and Orhaug (1975). 
Experiments of forest inventory from Landsat 1 data 
In Sweden there is a need to complement detailed forest maps on the scale 
1:20 000 with updated general maps in 1:100 000 or 1:250 000, e.g. for plan- 
ning and controlling forest regeneration. In order to testify these possibi- 
lities from Landsat data an area of 256 x 256 pixels at Kroppefjäll in Dals- 
land was investigated using two Landsat scenes: Sept. 4 1972 (1043-09574) and 
June 18. 1973 (1330-09523). The classification system used is shown in Table 1. 
In Figure 1 and 2 illustrations are given of the spectral characteristics 
for some of the type objects used. In Figure 3 an account of the computer 
classification of the Sept. -72 Landsat registration at Kroppefjdll is pre- 
sented in a color coded ink jet dum plotter rendition.