Ensuring food security in China
(2009-06-14 13:06:54)
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杂谈 |
分类: 建言新农村 |
Ensuring food security in China |
Jiang
Gaoming
Water scarcity affects 184,000 square
kilometres (276 million mu)of farmland in northern China, as the
worst drought for half a century grips the region. It has put food
security back on the agenda, and revealed a lack of investment in
agricultural land. The drought has also triggered discussion about
new crops that can cope with these conditions. Monsanto, the
multinational agricultural biotechnology firm, recently announced
plans to market a drought-tolerant strain of maize earlier than
expected, after four years of development. Irrigation will provide
inadequate water for China’s fields, say some experts. The
cultivation of drought-tolerant crops seems important.
But are genetically-modified crops
the best way to improve harvests? Aside from food safety issues,
they may not be a good idea. The factors that affect Chinese food
security are the area farmed, and the yield per unit of area. Yield
is more affected by the quality of the land than the nature of the
crop. Without a major increase in yield, decreases in the amount of
land that is farmed or a shortening in the growing season result in
decreased harvests. GM technology only has a role to play where
fertilisers, pesticides and herbicides are used heavily. All of
these technologies replace labour: people do less work, the soil
becomes less fertile and pollution worsens. In the long term, the
key factor in food production – soil fertility – is not improved
but diminished. As the GM industry overwhelms agriculture, farmers
will have less freedom over their work and will become less
inclined to plant staple food crops.
According to Li Zhensheng, an
award-winning expert on the genetics of wheat, yields in the 1950s
were very low: around 100 kilograms per mu. At that time, harvests
were limited by the area of land planted. Investment in
agriculture, including irrigation, the use of chemical fertilisers
and mechanisation, increased from 1962 to 1995. This and the
household-responsibility system – which motivated farmers to
increase harvests – saw yields rocket to 283 kilograms per mu (667
square metres). Yield became the limiting factor. Since then, yield
has remained around 300 kilograms per mu: 314.4 kilograms in 2006,
286 kilograms in 2008. As in the 1950s, the area of land farmed now
determines the size of the harvest.
In the latter half of the last
century, there was progress in increasing soil fertility, which we
can still learn from today. Mao Zedong said that increasing
harvests required irrigation, soil improvement, extra fertiliser,
improvement of crop strains, closer planting, the prevention of
pests, the use of machinery and field management. All of these
measures can provide crops with the conditions for growth, and all
need investment in agricultural infrastructure. But today we
concentrate on a few technological factors: different GM strains,
fertilisers, and so on. Irrigation, pest control and field
management infrastructure receive no investment and fall into
decay. Labour is replaced by machinery; people become lazy. Vendors
of machinery, fertilisers, pesticides and agricultural membrane
take their cut; nobody worries about pollution or biodiversity
loss. Is it any surprise the soil suffers?
There have been huge advances in
agricultural technology in recent decades – in fertilisers,
pesticides, membranes, breeding and genetic engineering. The use of
fertiliser increases by two million tonnes every year. But despite
this, China’s harvests from 1999 to 2007 failed to reach the peak
of 1998. The limiting factor is not technology; further investment
in that direction only serves to increase costs. The problem is a
human one.
An elderly farmer from eastern China
told me that he often heard people say: “There is no money to be
made growing crops. Fertilisers and the rest are so expensive: the
more you plant, the more you lose. Just plant enough to eat.” In
economically developed regions, farmland goes to waste or is
covered with buildings. Fertile soil is being lost.
“Just plant enough to eat,”
encapsulates the threat to China’s food security. After the
household-responsibility system was implemented, farmers took care
of their own food security first. And when it became possible to
earn an income from growing crops, productivity rose. Today, costs
are high and grain prices are low, so farmers leave the land and
head for the cities. From the rich eastern coast to the poor
provinces of the west, it is mainly the old, sick or disabled that
remain in the villages. Even the women have left to find work. With
little available labour, only the minimum is ever planted.
This is the root of China’s food
security problem, and it is not an issue that GM crops can solve.
GM crops will only benefit the powerful and force more people off
the land. GM crops, combined with the use of chemicals, will
continue to harm soil fertility, decreasing food security.
Chinese food security is limited by
the fact that millions of rural residents simply will not plant
food crops, due to falling fertility and yields. For the sake of
our agriculture and that of future generations, we must use and
maintain the land as we did in the past. We need to increase
investment in agriculture; restore the irrigation infrastructure
that dates back to the 1960s; encourage intensive cultivation; and
ensure that working the land is profitable. We should not allow
fields to lie empty and fertility to drop.
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