ASSESSING THE RISKS OF LANDSLIDES IN MOUNTAINOUS AREAS
ISMAYILOV M.J.
1
, ISMAYLOVA L.A.
2
1
Institute of Geography named after acad. H.Aliyev
,
Azerbaijan National Academy of Sciences, Baku,
Azerbaijan
2
Azerbaijan State Oil and Industry University,
Baku, Azerbaijan,
E-mail:
Latifa.isamylova@gmail.com
Keywords: environmental, landslide, morphodynamic, natural disasters, economic losses.
1. Introduction
In recent years, mountain geosystems were under the influence of considerable anthropogenic
load, driven by such factors as the rapid development of new settlements, the laying of new asphalted
motorways, the construction of industrial facilities as well as the development of mining industry. In this
regard, the investigation of landscape- and geomorphological processes, posing
a hazard to the sustainable
development of the natural-economic systems in the mountainous areas, as well as the forecasting and the
prevention of this processes are regarded as topical issues. High seismicity in the southeastern part of the
Greater Caucasus favourably affects the occurrence
of morphodynamic processes, including the landslides.
The preliminary assessment of hazards and risks posed by landslides in the mountain areas through the
application of up-date methods may prevent or reduce damage.
This work has been carried out due to financial assistance of the Science Development Fund under
the President of the Republic of Azerbaijan (Grant No. EIF-2012-2(6)-39/15/2).
2. Materials and methods
The GIS-based landslide risk model of (Mora et al., 1994) was used. The first group of reasons
includes are the main reasons of while the second group takes are responsible for the activation of
landslides. The morphometric parameters of relief along with the lithological composition of rocks and the
soil moisture index are listed as the main reasons of landslides, while the average perennial precipitation
and seismicity were considered as activating factors. The factors were analysed through GIS in accordance
with the following formula:
A(fet)
landslide
= (S
d
x S
lc
x S
sm
) x (T
al
+T
sr
)
(1)
where S
d
is the degree of inclination of slopes; S
lc
is the lithological composition of rocks; S
sm
is soil
moisture index; T
al
is the average monthly amount of precipitation in multiyear period; and T
sr
is the
seismicity rate.
Landscape- and environmental risks of landslides were identified with taking into account the
specific characteristics of the studied southeastern slope of Greater Caucasus as well
as such factors as
anthropogenic loading, land use, relief, vertical and horizontal fragmentation, indices of landscape’s
ecomorphological tensity and factors of landscape- and environmental assessment. Relatedly, the following
formula was used:
N
S
S
S
fic
i
:
∑
∑
=
(2)
where S
i
is the landslide intensity index; S is the area affected by landslides; S
fic
is the total area of factors,
involved to the
comparison; and N is the number of measurements.
Researchers note that the correlation between the indicator of landslide intensity index and the
level of landslide-related risk and hazard is available. Then the gained data was analysed through GIS. The
last phase of was carried out based on the following formula:
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fic
eb
tf
lc
vc
sd
si
e
i
vt
l
a
i
S
S
S
S
S
S
S
S
S
S
S
S
S
S
dr
+
+
+
+
+
+
+
+
+
+
+
=
(3)
where S
a
is the anthropogenic loading; S
l
is the use of lands; S
vf
is the vertical fragmentation of relief; S
e
is
the eco-geomorphological tension; S
si
is the inclination
of slope; S
sd
is the direction of slope; S
sc
is the
curvature of slope; S
vc
is the vegetation cover; S
lc
is the lithological composition of the rocks; S
tf
is the
tectonic fracture; S
dr
is the distance from rivers;
S
dr
is the distance from roads; and S
eb
is the environmental
balance.
3. Results
In order to assess landscape- and environmental risks and hazards, posed by landslides in the study
area, the existing areals of landslides were compared with the maps of land use (I), extent of vegetation
cover (II) and also landscape and environment (III) of large scale (1:10000). Based on this comparison and
the above-mentioned formula, the intensity indexes of spread of active landslides through ArcGIS program
were measured (Fig. 1).
Figure 1. Landscape and environmental risks and hazards caused by landslides
The legend of map of landscape- and environmental risks and hazards caused by landslides:
I. Landscapes of mountainous forests in low mountain areas. 1. Secondary forests, composed
of oak and hornbeam and widespread over brown forest soils of highly shattered slopes of medium
hazard of sliding (25º-35º of inclination). 2. Secondary sparse arid forests, composed of hornbeam,
elm, oak, hawthorn, shattered at medium extent, with medium hazard of sliding (20º-25º of
inclination). 3. Trees and shrubs like elm, hornbeam, hawthorn, blackthorn, etc.
widespread on brown
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