Iu 
ch 
  
which developped on silty-argillaceous colluvial sediments or on 
recent floods, usually have a considerable depth, but a slow 
drainage especially near vast argillaceous grounds. 
Land-unit e): 
It is characterized by grounds having a slope comprised 
between 8% and 15% and is not interested by overflows. Eventual 
hydro-morphism phenomena take place in greater drainage areas. 
Vegetation is consequently characterized by the intercalation of 
Primary and Secondary Forests. From a morphologic point of view, 
this land-unit represents a connection between land-units b) and 
c), and it is in general scantily present in the examined zone. 
The soils which develop almost only on weakly consolidated mioce 
nic sediments are deep and have, in general, a good drainage. 
Land-unit d) 
It is characterized by an undulating, hilly morphology, 
with reliefs slopes higher than 15%, together with sharp breaks 
of slope ending even in escarps and precipices; vegetation is 
characterized by a thick Primary Forest protecting the soil 
against erosive phenomena; only where the forest is missing, 
often due to human action, the soil quickly erodes thus forming 
channels, mud-flows and pyramids of earth. The soils are usually 
well-drained, with a depth lower than 1 meter and a weakly 
cohesive sandy substratum. 
Land-unit e) 
It is characterized by usually depressed areas, inside of 
which water always stagnates. It represents an unit comprised 
among those previously described with a Swamp Grassland-type 
vegetation. The soils, which present an alluvial-colluvial 
substratum, are almost usually saturated of water, thus ob- 
structing inner drainage and bringing about phenomena of radical 
asphyxia. 
Conclusions: 
Adopted methodology revealed itself to be perfectly suita 
ble to obtain within short times, the physical and environmental 
characteristics of less-known and hardly accessible zones. As 
regards the execution times, it is not possible to be more preci 
se, since they obviously depend on factors, as photograms scale 
and its quality, type of available mosaic and so on, which vary 
case by case. 
In particular and as regards examined country, suggested 
methodology has clarified, through base-thematic maps and sur- 
veys, the absolute lack of necessary and sufficient conditions 
of the establishment of new human inhabitations, either for the 
risk of floods in flat areas or for the impossibility to grow 
959