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)