Transcript SEBI 14 Serbia

SEBI 014 Fragmentation of river
systems
Institute for Nature Conservation of Serbia
Serbian Environmental Protection Agency
Slavisa Popovic
Jasmina Mijovic Magdic
1. About 170 dams and accumulation in Serbia
2. About 80 dams in SeLaR database with technical properties
3. Length of rivers is 8971,65 km
Sub-indicator: Barrier density (index)
Barrier density = Number of dams / Length of rivers
BD index = 170 / 8972
BD (i) = 0,01895
Sub-indicator: Number of dams by height
18
16
14
12
10
8
6
4
2
0
Height 110m
Height 11- Height 21- Height 31- Height 41- Height 51- Height 61- Height 71- Height 81- Height 91- Over 101m
20m
30m
40m
50m
60m
70m
80m
90m
100m
Sub-indicator: Number of dams by years
25
20
15
10
5
0
1930-1950
1951-1970
1971-1990
10/24/13
1991-
Sub-indicator: Number of rivers with more than 1 dam (Super-fragmentized
rivers)
More than 70 rivers have 1 dam
12
10
8
6
4
2
0
2 dams
3 dams
Sub-indicator: Number of dams with fish path
How to interpret the indicator:
River fragmentation disrupts the natural biophysical and ecological processes
essential for maintaining life in freshwaters.
Dams disconnect rivers from the surrounding floodplains,
block migratory fish passage, and retain sediments and nutrients
that nourish downstream ecosystems.
Reservoirs turn running water habitats into lake-like systems,
resulting in the disappearance of fish species adapted to riverine habitats
and the proliferation of other, often exotic species adapted to still waters.
In highly fragmented rivers the diversity of life is likely to have been reduced
and the adaptive capacity of native species impacted.
Therefore an increase in river fragmentation indicates a higher
likelihood of biodiversity loss as well as a disruption in ecosystem service delivery.
How to interpret the indicator:
1. Pressure: BD(i), High of dams…
2. Mitigation: Fish paths…
3. Species: NoSpecies, Area…
4. ?...
The Iron Gates Dams and Disruption of Spawning Migration
Iron Gates dam
Located just below the Iron Gates gorge (Đerdap) between Romania and Serbia, Iron Gates
is the largest hydropower dam and reservoir system along the entire Danube. The system
consists of two main dams, Iron Gates I and II, built in 1972 and 1985 respectively. The dams
are constructed at river km 942 and river km 863 upstream of the Danube delta, in effect
confining migratory sturgeons to 863 km of the river and cutting off important spawning
sites in the Middle Danube. Iron Gates is jointly operated by Romania and Serbia.