Environmental Engineering Reference
In-Depth Information
Figure 5.3
Irrigated fields dependent on snowmelt regime in the Oued Yagour River Basin
in High Atlas, Morocco (photo: Simmoneaux). Reproduced from Ludwig
et al.
(2009), with
permission
significant improvements are required to establish precise data for snowfall/rainfall
precipitation and discharge. The lack of literature on Decision Support Systems
for water resources originating from mountains is almost certainly due to the poor
quality and quantity of such input data. The same problem applies to the esti-
mation of the relative contribution of snowfall to the annual water budget and
groundwater. For example, it is estimated that 12% of the Hermon aquifer recharge
below Mount Hermon (Israel) is replenished by snowmelt (Rimmer and Salin-
gar, 2006). In the Tensift catchment of the High Atlas, Morocco, more than 60%
of the specific annual discharge of only 0.34 L/s/km
2
is derived from snowmelt
(Figure 5.3). More than 75% of the total discharge is used for irrigation of agricul-
tural land in this catchment with an average population density of 98 persons/km
2
.
In contrast, the Dalaman catchment in Turkey has a specific annual discharge that is
36 times higher, at 12.4 L/s/km
2
, of which snowmelt accounts for 40-50%. Again,
more than 70% of this low specific discharge is used for irrigation agriculture in
a catchment that has nearly double the population density with 189 persons/km
2
.
On the whole, Turkey, Algeria, Morocco and Italy have the highest percentage
of mountain populations in the Mediterranean. For some of the most densely
populated mountain basins, such as the Jordan in Lebanon and Oued Sebaou in
Algeria, precise snow-related discharge data are lacking. Nearly all mountainous
catchments that use more than 70% of their total water for agriculture depend on
