ST 
remote sensing techniques. The number of values in each series was 107. The 
hypothesis about the same distribution of the values from the two series could 
not be rejected on a 95 percent confidence level. The actual percentage values 
have been compared to each other for each subcatchment. The maximum deviation 
was around 10 percent which is quite acceptable for hydrological applications. 
For lakes the most deviations were positive, which can be explained by the 
age of the maps (more than 10 years old). Natural eutrophication of lakes could 
have caused the transformation to swamps or to total disappearance. The results 
of the present study are of the same character as these presented in a report 
from Hydrological Engineering Center {LILY 
CONCLUSIONS 
Classification of Landsat-data is one means of obtaining necessary data for 
hydrological models. Data can be obtained for large areas on a generalized 
level or on a detailed level for watershed monitoring. The accuracy of obtained 
data is sufficient for hydrological modelling. 
The study is now continued in the direction of increased land use classes and 
improvement of interpretation methods. 
REFERENCES 
/1/ HEC, 1979, Corps of Engineers, U.S. Army:"Determination of land-use from 
Landsat imagery applications to hydrological modelling". Research note No 7 
/2/ | Gottschalk, L. and Krasovskaia, I.:"Computer bases mapping of compre- 
hensive hydrological information", Uppsala University, UNGI Rapport 
Nr 53, 1980. 
/3/ | Gottschalk, L. and Krasovskaia, I.:"Synthesis, processing display of 
comprehensive hydrological information", SMHI, RHO 22, Norrköping. 1980. 
/4/ | Gottschalk, L., Krasovskaia, I. and Kvist, H.:"Computorized representation 
of a watershed for hydrological modelling and planning." Department of 
Water Resources Engineering, Lund Institute of Technology, University of 
Lund. Report No 3056, 1982. 
/5/  Talts, J.:"Klassning av Landsat-data für hydrologiskt informationssystem." 
National Land Survey. Professional papers 1981:5. (in Swedish). 
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