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SYMPOSIUM PHOTO INTERPRETATION, DELFT 1962 
Detailed analysis of landforms in the area of interest should be concerned 
with configuration and space relationships. Regional analysis of drainage 
systems reveals indications of relative depth and texture of overburden, uni 
formity of materials (areal and vertical) and relative resistance to erosion. 
Local drainage study can indicate soil moisture - ground water and internal 
drainage conditions, and thermokarst areas. Erosional features, such as gully 
systems and gully characteristics, reveal information about soil textures and 
uniformity, while solifluction and other frost-formed features indicate seasonal 
thawing of the active zone and possible gravity flow of the materials. Vege 
tative types may be used as indicators of permafrost soil and drainage condi 
tions. For instance, aspen are usually found on dry, unfrozen slopes and 
willows are generally restricted to sites near bodies of water with permafrost a 
few yards below the surface. Coupled with species identification are such im 
portant site features as slope, exposure, altitude, density, etc. Photo tones can 
reveal differences in soil texture, moisture conditions, elevations and vegetation. 
In addition to the detailed study given to the above minute features, there 
are other features indigenous to arctic areas which reflect further the effects 
of the arctic environment - the permafrost and severe frost acting features. 
Such items as polygons, pingos, mud boils, solifluction lobes, stone and soil 
strips, leaning trees and many more are often seen on good quality airphotos. 
Fig. 5. Examples of some arctic landforms 
Fig. 6. Examples of arctic vegetation related to landforms and conditions