A kind of China-developed drop irrigation technology is expected to
bring relief to countries around the world plagued by water
shortage.
The technology, developed by Chinese irrigation experts, employs a
type of drop irrigation under plastic film, according to Gu
Liefeng, an official with the Xinjiang Production and Construction
Corps who is in charge of water conservation efforts.
It
blends the advantages of Israeli drop irrigation and the Chinese
technique of using plastic film in farming. The new method has been
proven very effective in water conservation in arid areas.
Field experiments have shown that the technology can cut water
consumption by 50 percent per mu (0.067 hectares) of farmland
compared with conventional irrigation methods such as flood
irrigation.
It
has also shown that it can increase grain output between 10 and 20
percent and generate higher economic returns. In addition,
evaporation can be reduced significantly.
The drop irrigation under plastic film technology was initially
developed and tested in the 1980s in the reclaimed farmlands in the
Shihezi area, sandwiched between the Tianshan Mountains and the
Gurbantunggut Desert in the northern part of Xinjiang Uygur
Autonomous Region, in northwest China.
Shihezi is a typical arid region with an annual rainfall as low as
100 to 200 mm and an annual evaporation rate as high as 2,000 to
2,400 mm. Agricultural operations rely completely on irrigation,
and per mu (0.067 hectares) water consumption is about 500 cubic
meters.
To
date, the technology has been put into use on more than 113,000
hectares of farmland in Xinjiang, one of China's major arid
regions. It is expected to be employed on more than 266,000
hectares in Xinjiang in the near future.
Despite the advantages of drop irrigation, excessive price has
restricted its application. In fact, until recently, drop
irrigation technology had been limited to gardening and vegetable
cultivation.
The Xinjiang Tianye
Co., Ltd has developed a kind of drop irrigation belt. The
price per meter of the irrigation belt is 0.2 yuan (US$0.024),
one-fifth of the cost of the same type of irrigation equipment on
the world market.
The drop irrigation belt developed by the company costs only 5,250
yuan (US$634) per hectare of farmland compared with 36,000 yuan
(US$4,353) for drop irrigation equipment developed by Israel, which
boasts the most advanced drop irrigation technology in the
world.
The combination of drop irrigation technology, plastic film
technology and inexpensive drop irrigation equipment has made it
possible to apply drop irrigation to large-scale farming and has
enabled ordinary farmers to enjoy its benefits.
Shi Yuanchun, an academician with the Chinese Academy of Sciences
and the Chinese Academy of Engineering, takes this technology as "a
breakthrough in drop irrigation technology and an innovation in the
water conservation history of the world."
Wang Xingui, a farmer in Shihezi, has been using the drop
irrigation under plastic film technology in the cultivation of
cotton for four years.
He
used more than 500 cubic meters of water to irrigate one mu (0.067
hectares) of cotton in the past, he now uses only about 200cubic
meters. Moreover, his per mu cotton output has increased from 200
to more than 300 kg. He earns 170 yuan (US$20.5) more per mu of
cotton than in the past.
This year, his family grew 2,900 mu (193 hectares) of cotton and
will harvest 1.5 million yuan (US$180,000) worth by the end of the
year, Wang said.
Currently, more than 100 farm families in Wang's area are using
drop irrigation technology in the cultivation of cotton.
Xinjiang is one of China's major cotton production and export
bases. The region's annual cotton output stands at about 1.5
million tons, more than one-third of China's total.
"It is a miracle that ordinary Chinese farmers can afford to use
such a modern and effective water conservation technology," said
Jiang Kaipeng, an official with the Ministry of Water
Resources.
He
said the development and popularization of such technology is very
important in China, a country with a huge rural population, fragile
conditions for agricultural production and low income for
farmers.
Apart from Xinjiang, farmers in northwest China's Gansu and Shaanxi
provinces have also used the technology to grow crops and cultivate
vegetables.
The technology has even brought benefits to foreign countries.
According to a contract signed between Xinjiang Tianye Co. Ltd.,
and a cotton investment company in Tajikistan, the Xinjiang company
employed China's drop irrigation technology, together with its own
drop irrigation belts and fertilizer, to grow 32 hectares of cotton
in arid areas of Tajikistan in 2001.
Per hectare water and fertilizer consumption was reduced by 70
percent and 30 percent respectively, and per hectare seed cotton
output increased by 218 percent to more than three tons from 1.9
tons in the previous year. Per hectare income grew by 202 US
dollars.
As
an assistance program of the Chinese government, the scope of the
project in Tajikistan has been expanded to 267 hectares this year,
and the scope is expected to expand even further in 2003, said Wang
Can, general manager of the Xinjiang Tianye Company.
China is one of 13 countries facing serious water shortage. Its per
capita water volume is only one-fourth of the world average. Flood
irrigation in the agricultural sector accounts for more than70
percent of the country's total water consumption and wastes a great
deal of water.
Jiang, the official with the Ministry of Water Resources, said drop
irrigation under plastic film could fundamentally change the way
China uses water in the farming sector and help China to use its
water resources in a more effective way.
This technology is also expected to promote the development of
modern agriculture in China and improve the competitiveness of its
agriculture on the international market, Jiang noted.
(Xinhua News Agency December 31, 2002)