Aibi Lake (File photo)
Due to shrinking surface area, Xinjiang's largest salt lake,
Aibi Lake, has increased the desertification of the area and
subsequently transformed into one of China's major sandstorm
sources.
Down to just 500 square kilometers from its original 1,200, Aibi
Lake has become a direct threat to the sustainable development of
the Economic Belt on the northern slope of the Tianshan Mountains
and the security of the new Euro-Asian Continental Bridge.
With the smaller surface area, water resources from the lake
have been reduced to 600 million cubic meters from 3 billion cubic
meters. Shrinkage has also increased the salt content of the lake
water yearly, which has now reached 3 percent, close to the average
salt content of seawater.
The decrease in water has transformed the surrounding areas of
Aibi Lake into a 1,500-square-meter desert belt, expanding at a
speed of 39.8 square meters per year. Under the hot sun, large
amounts of salt become particles less than 0.02 microns in diameter
at the dried lake bottom.
According to the Xinjiang Environmental Protection Bureau, these
tiny salt particles are more easily blown into the air than sand
dust. Each year more than 4.8 million tons of salt dust is blown
from the Aibi Lake area. The strong wind from Alataw Mountain Pass
may blow them more than 5,000 kilometers away, constituting a big
threat to the plants, crops, and people of all northern China.
According to Gao Xiang, Party chief of the Aibi Lake Wetland
Nature Reserve Administration, the salt dust has accelerated the
melting of glaciers in Bortala Prefecture, where the sandstorm
weather has risen to 110 days from 13 days since the 1960s.
Gao said that the Aibi Lake Wetland Nature Reserve had 385 kinds
of wild plants registered, but a 2005 investigation showed that
there are only 322 kinds of plants left. The nature reserve has 111
kinds of bird species, numbering 1 million in total, but a strong
wind could kill more than 10,000.
"If the comprehensive ecological treatment of the Aibi Lake area
succeeds, it will erect an ecological protection shelter in
northern Xinjiang; if it fails, the salt dust will directly
threaten the ecological environment of the Hexi Corridor and all
North China," Gao remarked.
Aibi Lake (File photo)
According to the Bortala Forestry Bureau, water shortages have
led to the shrinkage of the Aibi Lake surface. Three rivers
including the Kuytun, which previously supplied 45.8 percent of the
Aibi Lake water, dried up in the 1970s. Reduced supply of river
water combined with severe lack of rain, about 90 mm per year, has
caused a serious imbalance between the supply of lake water and
evaporation.
Each year 713 million cubic meters of lake water evaporates, but
the average water supply to the lake is only 662 million cubic
meters. In addition, the increased population and expanded
irrigation areas after the 1970s also sped up the shrinkage of the
lake surface.
Various measures have been enacted to help solve the ecological
problems around Aibi Lake including water conservation, tree
planting and a limit on logging and hunting to protect the
lake.
"The fundamental ecological problem of Aibi Lake is a water
shortage," noted Wang Xinhe, a member of the Bortala People's
Congress Standing Committee.
In order to maintain the existing Aibi Lake surface, the
prefecture saves 20 million cubic meters of water per year to
guarantee a water supply of 600 million cubic meters to the lake.
But Bortala is running short of water resources with its economic
and social development.
Wang Xinhe said helplessly, "Bortala's limited water resources
are far from satisfying the water supply to Aibi Lake. The current
situation constitutes a massive pressure to the sustainable
development of the prefecture's society and economy and the
coordinating development of population, resources, and
environment."
According to preliminary estimates, an additional 1 billion
cubic meters of water is needed to cover the dried lake bottom and
deal with the surrounding deserts.
In 2004 Xinjiang launched a water project in the Aibi Lake area.
Phase I of the project with a total input of 20 million yuan, will
be accomplished by 2010. Each summer and winter, related
institutions will fire rain enhancement devices using rockets or
artillery to supply more water to the lake.
The air over Aibi Lake contains abundant vapor water and tuning
this vapor water into liquid water will effectively supply water to
Aibi Lake, according to the Xinjiang meteorological department.
"In the long run, in order to win the battle to protect the
lake, water transfer projects must be put on the agenda," Wang
Xinhe explained. Inter-basin water transfers can increase the water
volume of Aibi Lake, extend its surface, elevate its underground
water level, and maintain and develop existing plants around the
lake area.
"Currently the deterioration speed of the Aibi Lake ecological
environment is much faster than the improvement speed. Protection
of the Aibi Lake area requires the concerted efforts of people from
all walks of life," Wang added.
(China.org.cn by Zhang Ming'ai, November 30, 2007)
