In many cases the values of potential risk 
coincide with the present intensity of the 
erosion processes.The -maximun erosion risk 
arises in the cultivated areas of the moun 
tainous region with wet sub-tropical climate 
where it is urgent to apply practical conser 
vation measures. The areas still not cleared 
shows a low risk, on condition that the pres 
ent management is preserved. In the plain a- 
reas the potential erosion values are moder 
ate, despite of low gradient, because of the 
high erosion susceptibility of the soil and 
the aggressiveness of the climate. 
The coincidence of the extreme of soil loss 
values of the region, characterized by a sub 
tropical climate, with the categories estab 
lished by S.A.E1 Swaify (1977) for Hawa i 
must be pointed out: the values for Hawai are 
higher than the ones measured normally in re 
gions of temperate humid climate. The rela 
tively high values of soil loss can be attri 
buted the regional climate aggressiveness, 
the instability of the vegetal coverage and 
the predominance of loessic soils. 
del paisaje natural. Acta Geolôgica Lilloa- 
na 1 5-b ■ 
Townshed, J.R.G. 1981. Regionalization of ter 
rain and remotely sensed data. In Terrain 
Analysis on Remote Sensing. George Allen and 
Unwin, London . 
Tricart, J. 1982. Taxonomical aspects of the 
integrated study of the natural environment. 
ITC Journal 1 982 - 3 : 3^ " 3 ^8 . 
Van Zuidam, R. 1983. Guide to geomorphology 
aerial photographic interpretation and map 
ping. Section of Geology and Geomorpho1oqy 
ITC, Enschede. 
Verstappen, H.Th. 1983. Applied Geomorphology. 
Elsevier. 
Wischmeier, V/.H. & D.D. Smith. 1978. Predict 
ing rainfall erosion losses. A guide to con 
servation planning. U.S. Department of Ag 
riculture, Agriculture Handbook № 537. 
Zonneveld, J.I.S. 1983- Some basic notions in 
geographical synthesis, Geo-Journal 7-2:121- 
129. 
CONCLUS IONS 
- The quick inventory of the erosion hazard 
in extended regions allows to detect the 
most affected areas, a fact which contrib 
utes to the implementations of conservation 
programs at the regional level. 
- The use of a geomorpho1ogica1 basis, the 
methodological criteria of the USLE and re 
mote sensing techn i ques ' g i ves the mapping 
at small scales scientific objetivity and 
allows it to be rapid and economic. 
- The use of the Universal Soil Loss Equation 
has advantages from other parametrical meth 
ods for its relative simplicity and great 
divulgation. The limitation derivated from 
the application of averages of the erosion 
factors are minimized by the regional char 
acter of the appraisement. 
- The use of Landsat information by both vis 
ual and/or digital interpretation gives 
planimetric reliability and mu 1ti-tempora1 
information of the landscape dynamics. 
- The studied area shows, in general, a high 
erosion risk due to the increasing anthropic 
pressure on extended areas which are still 
covered by natural vegetation. 
ACKNOWLEDGEMENT 
I wish to tank Dr. Van Zuidam for his assist 
ance and valuables comments during my perma 
nence in ITC and also in the field work period 
in Argentine. 
REFERENCES 
Arnoldus, H.M.J. 1978. An approximation of 
the rainfall faotor in the universal soil 
loss equation. In assesment of Erosion. M. 
de Boodt and D. Gabriels (eds.) John Willey 
and Son, New York. 
Bergsma, E. 1982. Aerial Photo - interpretat i on 
surveys. ITC lectures notes part. II and III. 
El-Swaify S.A.1977. Susceptibility of certain 
tropical soils to erosion by water. From 
Soil conservation and management in the 
humid tropics. John Wiley and Sons. 
Janssen, M. 1983. Land erosion by water in 
different climate. Upsala University, Depto. 
of Physical Geography. Report N°57- 
Sayago, J.M. 1982. Las unidades geomorfo1ógi- 
cas como base para la evolución integrada 
Sympos 
The st 
Varoujan 
Geological 
ABSTRACT 
dying of 
with the 
discusse« 
INTRODUCE 
Mass move 
of rnovem« 
in soils 
sons. Tht 
shape, sj 
more shes 
slide) 01 
system oi 
Mend 19( 
Mass me 
huge dame 
ties, li\ 
these ree 
the moveri 
are Heim 
Terzaghi 
lyanova 1 
Stepainan 
Nemcok et 
These a 
depending 
1. Form 
2. Kind 
3. Age 
4. Stag 
But sti 
tifying t 
type of m 
material 
on the sc 
use "only 
in pure f 
Aerial 
scale 1:1 
studying 
like thei 
critical 
of the mo 
very necc' 
of large 
work or o 
is involvi 
mmended, : 
deration 
use is re< 
Harold ' 
1978, Van 
1 CLASSI FI 
PHOTO GRAFI 
In this s1 
movements