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SYMPOSIUM PHOTO INTERPRETATION, DELFT 1962 
landforms within the region. As most of the alluvial plains in Japan have been 
built up by repeated flooding, the history of inundation is contained in their 
micro-topography. 
Landform classification mapping with aerial photographs, showing 
the relations to flooding 
The authors analysed the landforms of the plains in the lower courses of 
the large rivers in Japan by photo interpretation and field investigation. Since 
1959 they have been producing the “Topographical survey map with classifi 
cation of areas liable to flood”, or the “Landform Classification Map for 
Flood Prevention”. 
The first stage in the normal procedure for making this map is the prepara 
tion of a provisional map by aerial photo interpretation. This provisional 
survey not only increases the efficiency of the necessary field investigation, but 
Fig. 1. Map of micro 
topography classifica 
tion of the lower course 
of the Kiso River, show 
ing flood types of the 
region. 1. mountains; 
2. terrace; 3. fan; 4. 
natural levee; 5. back 
marsh; 6. delta; 7. re 
claimed rice field; 8. 
submerged agricultural 
land; 9.swamp; 10. dry 
river bed; 11. tidal limit