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
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