Post on 09-Feb-2022
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Aral Sea Syndrome
- “… refers to the problems associated with centrally planned, large-scale projects involving water resource development”
- Desiccation of Aral Sea = “the greatest environmental catastrophe ever caused to regional water resources by mankind”
Source: Micklin 2008. Total area 180 million hectares, 7.9 million hectares irrigated with more than 95 km3 of water annually
The Aral Sea map made by materials of A.I. Butakov expedition in 1848-1849
0 500 1000 km
15. Ladoga Lake, Russia(18 300)
14. Lake OntarioCanada/USA
(19 400)
11. Lake Erie,Canada/USA
(25 680)
6. Lake Michigan, USA
(58 020)
5. Lake Guron, Canada(59 580)
3. Lake Victoria, Africa(68 800)
4. The Aral Sea,Uzbekistan/Kazkhstan
(65 500)
1. The Caspian Sea(371 000)
7. Lake Tanganyika, Africa
(32 900)
13. Lake Malawi, Africa
(22 490)
10. Great Slave LakeCanada (28 570)
9. Lake Baikal, Russia
(31 500)
8. Great Bear Lake, Canada(31 330)
12. Lake Winnipeg, Canada(24 890)
2. The Upper Lake,Canada, USA
(82 900)
,
The Aral Sea was the 4th largest lake in the world according to surface in 1960 (comparative areas below in km2)
Source: Aladin et al 2007
Aral Sea: from 9000 to 1600 BC
Salinity: l – 0-3‰; l – 8-13‰; l – 13-29‰; l – 29-42‰; l – 42-51‰; l – >51‰
Source: Aladin et al 2007
BC BC
BC BC
Aral Sea: from 450 years ago, till now and in the future
Salinity: l – 0-3‰; l – 8-13‰; l – 13-29‰; l – 29-42‰; l – 42-51‰; l – >51‰ Source: Aladin et al 2007
ago ago
ago
Aral Sea water balance
Source: Micklin 2007
stable significant deficits
drought
Amudarya River annual flow 77 cub. km Syrdarya River annual flow 34 cub. km Water use in the ASB - 117 cub. km (95% for irrigated agriculture), did not reach the Aral Sea
Time-series: Aral lake based on Terra MODIS – 2000 to 2009 Source: http://www.mfb-geo.com/spip.php?article439; Credits: NASA / Earth Observatory
Desiccation of Aral Sea
- Area diminished by 74%; - Volume by 90% - Water salinity 10-fold increase
(from 10 to >100 g -1) - shoreline has receded 100 km - Creation of Aralkum desert - Extinction of native fish species
(http://commons.wikimedia.org/wiki/Image:Aral_Sea.gif)
NASA MODIS Image: May 11, 2007 - Dust Storm over the South Aral Sea
Desiccation of Aral Sea
- Collapse of the fisheries
- Collapse of local ecosystems
- Loss of livelihood for people
- Food security concerns
–Degradation of deltaic biotic
communities
– Initiation of dust/salt storms
- Local climate change
- Human health problems
- critical temperature loads. In summer
the temperature is extremely high,
winters bring severe frosts
Change of physico-geografical characteristics of the Aral Sea (1961-2011)
1961
1993
2011
1. Sea level
53 m
36.93 m
2. Water surface area
66 000 km2
33 000 km2
22 000 km2
3. Sea depth maximum
average
66.1 m
17.7 m
50 m
8.4 m
4. Salinity of water
10 – 11 %
35 – 36 %
> 100 g/L
5. Water volume
1 064 km3
277 km3
6. Drying area
0
3 270 000 ha
> 5 mln ha
7. Solonchaks
(adjoint territory)
98.5 km2
4 292 km2
22 m 5.3 m
90 km3
28.3 m
5893 km2
Can the sea be refilled and its economic, social, and ecological services reclaimed? At what cost and financed by whom? Should concerted efforts of the global community focus instead on adapting to consequences of the environmental crisis? Would it be sufficient from an ecological viewpoint?
Still open questions and concerns
“If everyone who came to study the Aral Sea had brought a bucket of water, the sea would be full by now”
• 20 large-scale international projects worth about US$500 million
• short term in nature and of little benefit
Solutions?
• (1) technical solutions
• (2) diversion from elsewhere
• (3) institutional solutions
• (4) political solutions
• Take no action
• “regional cooperation interests are above the national interests”
Technical solutions
• WUE increase
• infiltration and evaporation losses decrease
• improved ways of applying irrigation water
• alternative crops
• water-wise technologies
• introducing agroprocessing facilities
Institutional solutions
• water rights and water fees both at the user level (farmers) and at a higher level (governments of riparian states).
• abolish irrigated agriculture in the ASB
• Water management and coordination tasks were assigned to specially established river basin organizations of the Amudarya and Syrdarya Rivers
• the creation of reservoirs
• water allocation and management were transferred to the newly established Interstate Commission for Water Coordination (ICWC)
• IFAS—International Fund for Saving the Aral Sea - making decisions on water and the environment in the ASB
• “regional cooperation interests are above the national interests”
Political solutions
The International Fund for Saving the Aral Sea is a platform for better management of water resources whereas cooperation with international organization on various levels is of vital importance for consensus on effective use of limited resources.
Uzbekistan
Democratic, secular, unitary, Constitutional Republic since 1991 Total area 448 thousand sq km Population – 31 mln GDP (2014) - $61.720 billion Literacy rate – 99% Economy – industry, agriculture, services
Economic and Ecological Restructuring of Land and Water Use in the Region Khorezm (Uzbekistan)
Project duration: 2001 - 2011
Donor: BMBF
Project objectives:
Develop a comprehensive, science-based concept for
restructuring of Khorezm
- at three nested intervention levels: Policies, Institutions,
Land Use Technologies;
- provide decision support for consistent agricultural policies
based on
-Institutional restructuring
-Introduction of integrated technology packages for improved
land and water use (technical management level)
UrSU
27
Research on Water
Bio-physical
Institutional Socio-economic
Water aspects
Water saving options and water saving technologies on system and field level
Modeling and analysis of water saving options Water footprint analysis
SMID at selected WCA Water management training Irrigation scheduling
-10
0
10
20
30
J F M A M J J A S O N D
[°C]
0
20
40
60
[mm]
1980-2004
2005
Urgench (95 m)
[25]
13.4 °C 101 mm
• Continental cold arid desert climate
• Mean annual temperature 13.4°C
• Annual rainfall ~90 mm
• Annual evapotranspiration ~1500 mm
Climate in the ASB
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Source: Chub 2006
Extension of irrigation network (Aral Sea Basin and Khorezm)
* In 1999, these irrigation systems used 96.3 km3 water (98% of water resources) ** based on 1:25.000 GIS maps (ZEF/UNESCO GIS lab Urgench)
Aral Sea* Khorezm** (%)
Irrigation system area 7.9 M ha 250.000 ha 3
Canal length km km
main & inter-farm irrigation 28.000 1.895 7
main & inter-farm drainage 30.000 1.305 4
on-farm irrigation 168.000 14.338 9
on-farm drainage 107.000 6.374 6
Inhabitants 39.9 M 1.5 M 4
78% rural
* http://www.fao.org/ag/agl/aglw/aquastat/countries/uzbekistan/index.stm
Water Availability in the ASB
• Probability to receive 18000 m3/ha decreased between 1982 and
2007 from 84% to 67%
• Probabilities show a negative trend
0,67
0,69
0,84
200
210
220
230
240
250
260
270
280
290
1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006
Irri
gate
d A
rea [
1000 h
a]
0,60
0,65
0,70
0,75
0,80
0,85
0,90
Pro
bality
of
Su
ffic
ien
t W
ate
r S
up
ply
Area Probability
Assumption: Average irrigation intensity is 18000 m3/ha (OblStat 2002a)
• Poor leveling
• Partly irrigated fields
• Furrows not efficient
• Furrows are dry after irrigation
Inefficient water use
Raising flexibility of (water) management
flexible irrigation and leaching scheduling based on
modeling tools and advanced monitoring
appropriate hydraulic structures for discharge
control and dosage
partial loosening of the state-order system
(production instead of area quota)
strengthening water inspection
adequate water fee (on volume base)
appropriate cropping pattern
Raising flexibility
improving coordination of irrigation activities at the interface farm – network
(link to irrigation scheduling at WUA level)
creating space for decision-making at
farm level
Efficient irrigation and effective salt
management
Efficient irrigation and effective salt
management
improving the water application process (optimal application discharge,
surge flow, alternate furrow, double-side irrigation)
intermittent rice irrigation laser-guided land
leveling
modern irrigation techniques
(sprinkler, drip) conservation agriculture practices
appropriate cropping pattern
(tax) boni-mali system as incentive for efficient
irrigation and effective salt control
assuring land rights / creating long-term planning reliability
strengthening water inspection
advanced salt monitoring
Water saving technologies
More water-efficient technology is more expensive Low capital intensive but less water efficient measures (double flow, short and alternate dry furrow techniques) are financially attractive Capital intensive options could at present be initialized in home gardens, greenhouses, and private household plots
Source: Bekchanov et al. (2010) 44
Water saving technologies:
E.g. Systems level >
Plastic lining of channels
Field level> Laser guided land-leveling
Double side furrow-irrigation
Conservation agriculture
Drip irrigation
Bio-drainage
Hydrogel
Regulating infiltration
Water saving depending on the soil texture: Sandy soil up to 60-70 cm filtration (8000 cubic m per day) Loamy soil up to 40 cm filtration per day (4000 cubic m per day)
Leveling is key during irrigation. When
improperly done, salinity increases and
water and yield losses occur
Double-side irrigation
conventional
Qcon Qs1
Qs2
Results
water saving (gross irrigation depth): 20 % (vegetation period)
lowering of seasonal salt accumulation at the end of furrow: +50 % instead of +100 %
yield increase: 30 - 35 % WUE
Objectives:
test of ‚double-side‘ furrow irrigation as site-specific (zero-slope) technical option to improve water use efficiency (basic idea: more uniform water application along the furrow)
advanced modeling of the water application procedure (advance-recession-infiltration)
combining water/salt balancing model and application procedure model towards a complete field
irrigation model
double-side
cumlative infiltration
Conclusions: „Drowning in water scarcity“
• Sufficient water is circulating in the system
• High water losses occur – Conveyance losses (transport system)
– Water use for leaching also rises GW
– Annual and regional variation
• Water is used inefficiently
• Water insecurity forces farmers to rely on groundwater (conjunct irrigation) – Need to address this problem
Conclusions: Flexibility for water saving
• Water saving technologies can increase farm incomes, while improving farmer risk coping strategies in water scarce years
• Attractiveness of water saving technologies remains limited under present condition
• Increased farm flexibility in decision making can expand the adoption of water saving technologies
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• Dominance of rice in farm profits may result in undesirable resource allocations
• To prevent undesired effects, institutions for sustainable use of land and water are required
• -> Example -> A new concept for Water User Associations
• Return part of collected service fees will be used for social benefits to WUA members
• Potential for the WUAs to extent their service provision while simultaneously increasing their fees
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Conclusions: Setting new institutions
• Agricultural policies which address directly the improvement of livestock productivity and improvement of fodder quality can be an option
• In this respect, expanding fodder crops may contribute to improving resilience to irrigation water scarcity
• Promotion of local cotton processing sector will allow to maintain export revenues with less irrigation water use
Conclusions: Shifting priorities in production
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• Future total water requirement for food will likely continue to increase putting higher pressure on regional water resources
• Income growth will contribute to further increase in water demand for food -> higher dependency on food imports
• Reconsidering national trade structure with emphasis on food products with high virtual water content
• In addition to improving water use, options aiming to modify the food consumptions towards the diets with less virtual water content
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Conclusions: Shifting priorities in consumption
• Water quality water pollution from agricultural, industrial and municipal waste- and drainage waters
• major pollution sources
• collector drainage waters from irrigated fields: about 3-4 km3 are discharged directly into the river every year
health issues
Water Quantity vs. Quality
• No single blueprint for actions
• what is good for one location will not necessary cause the same positive effect in other places
• Options considering local specifications such as (population, water supply, land quality, design of infrastructure and markets)
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Finally…