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Chinese scientists are experimenting on irrigating crops with seawater
in vast areas of coastal provinces, in an effort to help feed its
huge population bothered by land and fresh water shortages.
Since early 1990s, almost 300,000 hectares of alkaline land and
mudflat stretching along the country's coastline, covering Shandon,
Heber, Ugandan and Hanna provinces, have been planting either wheat,
rice or oil crops, which is unprecedented around the world.
Like killing two birds with one stone, developing seawater- irrigated
agriculture is believed to be a way to create more farmland and
lower irrigation cost.
China's population accounts for one-fifth of the world's total,
but it only has 7 percent of the world's arable land.
Professor Xia Gagman with Shandon University estimated that another
40 million hectares of cultivated land, approximately one- third
of the total of the land that can be cultivated in China, could
be gained if all the alkaline land and beaches across the country
can accommodate crops.
If all that extra land can be used for planting crops, 150 million
tons of agricultural products could be yielded, about 30 percent
of China's yearly output.
In another aspect, seawater irrigation can mean a lot for China
who's per capital possession of fresh water equals only about one-
fourth of the world's average.
Water consumption for agricultural use in China accounts for 70
percent of the nation's total, and 60 percent of the cultivable
land was desperately short of water supply.
According to Professor Up Hibbing with the Hanging Oceanic University,
as much as 300 billion tons of fresh water could be saved, if seawater
is used directly to irrigate crops on alkaline land and beaches.
Compared with the technique to turn seawater into fresh water, it
would cost only one-thirtieth of the price to bring seawater directly
through canals or to plant crops directly in saline soil, suggested
up.
Since ancient times, almost all agricultural plants have to be irrigated
with fresh water. However, with crossbreeding and gene techniques,
Chinese scientists have cultivated a group of halophytes capable
of living in a saline environment.
A special species of wheat developed by Professor Ixia, for example,
reported nearly 400 kilograms of yield per mud (1 hectare equals
15 mud) and tastes exactly the same as wheat grown using fresh water.
Employing special techniques like cloning or "pollen canal
technique," scientists in the Chinese Academy of Sciences successfully
induced a hereditary element of halophytes into eggplants and pepper
and produced special species that can grow in a mudflat.
So far, the experiment is moving forward smoothly from the Yellow
River Delta in east China to the Pearl River Delta in south China,
where wheat and rice are growing in abundance.
Denying and Banshee counties, where seawater was first introduced
for irrigation, reported an annual increase of millions of kilograms
in agricultural output.
The sterile alkaline land in Gangway County was no longer a nightmare
for local farmers like Li Jeanine, who netted 100,000 Yuan per year
by planting rice and wheat that was resistant against salt.
A halophyte garden, cultivating some 80 species has been recently
set up in Shandon Province. However, scientists predicted that the
number of plants capable of using seawater could topple 400.
During the past five years, Chinese agriculture has witnessed marked
progress, but the Chinese government still regards it as a major
priority to restructure the agricultural structure, increasing farmer's
income and insure food safety.
Science and technology, the Chinese government believed, will be
the keystone for progress in the national economy including agriculture.
Now that the technical bottleneck has been conquered, China is very
likely to use land irrigated with seawater on a vast scale early
next century, said up confidently.
(Xinhua 12/22/2000)
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