The Aral Sea
Effects
Problems
Moving Forward
Background/History
Water supply replenished by the annual flows of the Syr Darya (SD) and Amu Darya (AD) rivers
amidst the deserts of Central Asia
4th largest brackish water lake in the world in the 1960's
Bordered by Karakum and Kyzulkum deserts and the Ustyrt Plateua
The Aral Sea has shrunk drastically in the last 50 years
largely due to water abstraction from the SD and AD rivers from land irrigation
Environmental
Local population
Dust storms, erosion, poor water quality
As the fisheries were depleted, the local population suffered economically
Fish species dropped from 32 to six due to rising salinity and loss of spawning grounds
Tragedy of the Commons
Once served as a major fishery
Was a regional transportation route
Irrigation (unsustainable)
60,000 related jobs were lost
previously average at 40,000 metric tons of fish
Health
Local populations suffer from high levels of respiratory illnesses from ingesting salt-laden air
The loss of fish also greatly reduced dietary variety, worsening malnutrition and anemia, particularly in pregnant women
Overall, extensive maintenance and new capital investments and necessary
Sustainable development
Ensuring that the needs of the present are meet without compromising the ability of future generations to meet their own needst
Large-scale expansions that were built quickly without extensive planning or risk assessments
Problems with poor irrigation can include: excessive water depletion, water quality reduction, water logging, and salinization
previously fertile, humus-rich, meadow/swamp soils have been transformed into low-productivity, sandy/desert soils with a much lower fertility
poor water distribution, drainage, and inefficient irrigation techniques
Creating sustainable irrigation
Goals - sustain irrigated agriculture for food security, yet preserve the associate natural environment
Access
35 million people lost access the the lake's water, fish, reed beds, and transport functions
High irrigation water withdrawals and large evaporation losses in the basin are widely recognized as the major cause for the decline of the Aral Sea
Climate, land use, and hydrology of the Aral Sea basin are tightly interconnected
any change to one of those systems will affect another
Current state of the Aral Sea
Divided into four small water bodies with a water level decline of about 25 meters since 1960
A dam was built in 2005 on the northernmost lake expand that has showed promising return of fish populations and wetlands
The two big southern lakes could potentially become dead seas -- unless there is drastic reengineering to the AD river. However, that would require tens of billions of dollars and cause a stir politically
The AD rivers course has drifted away from the sea, causing it to also shrink
The receding sea has exposed 54,000 square kilometers of seabed, which is full of salt and in some places laced with pesticides and other agricultural chemicals deposited by runoff from area farming
Liver, kidney, and eye problems
There's a high degree of exposure to contaminated dust for people living near the Aral Sea region
Strong windstorms blow salt, dust, and contaminants as far as 500 kilometers -- winds from the north and northeast drive the most severe storms -- which can impact the AD rivers delta to the south
Airborne sodium bicarbonate, sodium chloride, and sodium sulfate kill or negatively affect the growth of natural vegetation and crops
Over 90% entirely from those rivers
To reconstruct the former Aral Sea several sources were used
Geomorphological and sediment analysis of lake terraces and shorlines
Palaeolimological reconstruction of past environmental and climate changes from analysis of lake sediment cores
Analysis of the distribution of archaeological settlements and measurements on crustal vertical deformations
By 2007, the Aral Sea was half of its original size
The depletion of the Aral Sea is due to farmers using it as a limitless resource -- thinking that individually they aren't doing anything bad, but collectively are draining the entire thing
Use the Aral Sea as a TOC example
The commons = the Aral Sea
Other lakes are starting to follow suit -- Lake Chad in central Africa and the Salton Sea in southern California
Reduced river flows ended the spring floods that sustained wetlands and freshwater
In 2011, the connection between the AD river and the Aral Sea disappeared
click to edit
Most similar to pasture example -- each farm irrigated more water instead of added more cattle
Soviet government made the decision to divert AD and SD river from the Aral sea to the deserts for agricultural purposes
54,000 square km of exposed sea bed covered in salt, pesticides, agricultural runoff
REGULATIONS!!!!!!!!