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SYMPOSIUM PHOTO INTERPRETATION, DELFT 1962
Photo R.A.F. Archives Top. Service
Fig. 1. Aerial photograph of the Katem region, elevation 200 to 460 m. The shifting
cultivation areas are visible on the mountain slopes
(Manual of Photographic Interpretation. 1960. Chapter 11). However, these
mostly concern the agricultural systems in well-developed countries. Many
surveyors also know of applications in underdeveloped regions, e.g. the fact
that some scattered gardens in the middle of the jungle, visible on aerial photo
graphs, can indicate the presence of a soil type which is different from the
surrounding areas where those occupations cannot be detected. In this paper
attention will be drawn to the use of aerial photographs in dealing with
shifting cultivation patterns.
To restrict this very wide subject (see: Nye and Greenland, The Soil under
Shifting Cultivation, 1960), only systems occurring in the tropical rain forest
will be discussed, particularly those in the regions which are not over-culti
vated. These over-cultivated areas are very easily recognizable on aerial photo
graphs due to the lack of secondary forest. Nor will the really nomadic systems
be taken into account, where the tribes, or mostly one family, move from one
place to another, cultivating their crops - if they do so at all - on sites chosen