A wide range of soil types are found in Armenia (Map 5),
including 14 main soils. However, the country is extremely
poor in fertile lands suitable for agriculture. In the Ararat
Valley clay or clay-sand soil predominates, and the land is
generally wet and rocky. In contrast, mountain meadow soils
have the highest humus content (up to 12%, average 9%), which
compares favorably to humus content in other areas (4-9% in
forests, and 2% in deserts).
Table 1.4 Physical and ecological changes in Lake Sevan caused
by the decline in water levels
|
Indicators
|
Previous levels
|
Current levels
|
|
Decline in level (m)
|
0.0
|
19.2
|
|
Altitude (m)
|
1916.2
|
1897.0
|
|
Area of watershed (km 2)
|
3475
|
3647
|
|
Area of lake surface (km 2)
|
1416
|
1244
|
|
Maximal depth (m)
|
98.6
|
79.4
|
|
Average depth (m)
|
41.3
|
26.2
|
|
Volume of water (km 3)
|
58.4
|
33.5
|
|
Water exchage rate (yrs)
|
40.7
|
25.0
|
|
Water transparency (m)
|
14.3
|
4.5
|
|
PH
|
9.2
|
8.7
|
|
Total ions (g/m 3)
|
720
|
680
|
|
Dissolved oxygen (g/m 3)
|
6.0
|
2.0
|
|
Mineral nitrogen (g/m 3)
|
0.003
|
0.16
|
|
Total nitrogen (g/m 3)
|
0.07
|
0.64
|
|
Mineral phosphorus (g/m 3)
|
0.32
|
0.007
|
|
Total Phosphoros (g/m 3)
|
0.37
|
0.06
|
|
Bacteria (10 6 kl/ml)
|
0.4
|
1.0
|
|
Phytoplanton (g/m 3)
|
0.32
|
2.4
|
|
Biomas (gC/m 2/yr)
|
91.0
|
463.6
|
|
Primary production (Kkal/m 2/yr)
|
1000.0
|
5000.0
|
|
Microphytes (t 10 3/yr)
|
900.0
|
26.0
|
|
Zooplankton (g/m 3)
|
0.45
|
0.70
|
|
Zoobenthos (g/m 3)
|
3.38
|
11.0
|
|
Fish (t/yr)
|
1000.0
|
2400.0
|
Erosion has affected much of the soil in Armenia, generally
as a result of human activities (including unsustainable use
of croplands and overgrazing), and certain soil types (particularly
those associated with meadows) have been strongly affected
by human influence.
The mountainous nature of Armenia results in a series of highly
diverse landscapes, with variations in geological substrate,
terrain, climate, soils, and water resources. These landscapes
support a great variety of habitats, which support distinctive
flora and fauna, and different human use. Seven distinct landscape
zones are described in Armenia: deserts, semi-deserts, dry
steppes, steppes, woodlands, sub-alpine and alpine lands (Table
1.5; Map 6).
Table 1.5 Areas covered by different landscape zones
|
Landscape belts
|
Altiude range(m above sea level)
|
% of national territory
|
|
Deserts and semi-deserts
|
700-1300
|
10
|
|
Mountain steppes
|
1300
|
37
|
|
(wet grassland)
|
(375-700)
|
-
|
|
(dry gassland)
|
(1300-1600)
|
-
|
|
Forests,trees and scrubland
|
600-2500
|
20
|
|
Alpine and sub-alpine meadows
|
2100
|
28
|
· Deserts and Semi-deserts occur in the Ararat Valley
and adjacent mountain slopes at altitudes of 1200-1300m, in
the Vaik lowlands, and the Meghri gorge. Sand accumulations
in the Arax area result in a desert landscape, which are also
found in saline lowlands. In these landscapes climate is dry
and continental, with hot summers and moderately cold winters.
The soils are generally of the semi-desert grey type, and
have been managed for cultivation over the last millennia.
Cultivation has required intensive irrigation, and these areas
now support fruit, vegetable, flower, and wine production,
but have suffered major impacts from human activities.
· Dry mountainous steppes are found at higher altitudes
than semi-deserts (above 1500m) in the Ararat Valley, and
some other areas, but are also found at lower altitudes (above
800m) in the lowlands to the north-east of the country, which
were originally forested. The climate in the dry steppes is
characterized by warm, dry summers and mild winters. A range
of soils are found, but in the Ararat Valley these lands are
typically stony. Irrigation of dry steppes allows cultivation
of crops, vegetables and fruit, and these landscapes have
also suffered severe human impact.
· Mountain steppes are the dominant landscape for most
of the country, particularly at altitudes above 1500m (and
at altitudes up to 2000m in the north, 2400-2500m in the south).
Meadow steppes occur in the highlands, while patches of forest
also occur on ridge tops among steppes in the north-east and
Sjunik regions. Climate is generally moderate, with warm,
cool summers, and moderate or cold winters. Soils generally
have a humus content of between 6-7%. Steppes are used for
agriculture (including cultivation of crops, vegetables, frost-tolerant
fruit trees (in lower altitudes) and fodder plants (in highland
areas).
· Forests generally cover the mid-zone of mountains,
occurring at altitudes between 500m and 2100m in the north
(up to 2500m in the south). In central Armenia forests occur
in small areas rather than as a continuous zone, and forests
can be found on steep slopes, and other areas with limited
human access. Soil types include red soil in the lowlands
and forest gray soils in the highlands.
· Sub-alpine meadows occur at higher altitudes than
steppes and forests, including highland mountain ranges. Climate
is moderate with short, cool summers and long, cold winters.
Much of the land here is meadow, with soils of high humus
content.
· Alpine meadows occupy the highest altitudes above
sub-alpine meadows (up to 3000m in the north, 3800m in the
south). These meadows represent the principal pasturelands
for the country, with meadow and alpine vegetation. Climatic
conditions are severe, with long, cold winters, and annual
temperatures average less than -40. Snow cover lasts up to
9 months, and permanent snows may occur in some areas.
· Azonal landscapes cover over 10% of the territory
of the country, and occur independently of altitude (unlike
the previously described landscapes). These include wetlands,
as well as saline and alkaline lands, which cover about
25,000 ha, including areas in the Ararat Valley where the
underground waters are close to the earth surface, resulting
in water vaporization and salt precipitation. Upland wetlands
are dominated by fresh (non-brackish) water, while lowland
wetlands (particularly those around the River Arax) are
usually drained in summer, resulting in high salinity.
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