The ability of China to feed itself has important social and political aspects and recent history puts food production at the top of China's priorities.
China is coming to realise that being self sufficient in food may not be possible.
The article can be clicked on to get the full story. I show only a couple of highlights as a taster.
Can the United States Feed China? [Sustainablog]
As party leaders assessed the situation, they decided to launch an all-out effort to maintain grain self-sufficiency. The government quickly adopted several key production-boosting measures, including a 40 percent rise in the grain support price paid to farmers, an increase in agricultural credit, and heavy investment in developing higher-yielding strains of wheat, rice, and corn, their leading crops.
They offset cropland losses in the fast-industrializing coastal provinces by plowing grasslands in the northwestern provinces, a measure that contributed to the emergence of the country’s massive dust bowl. In addition to overplowing, they expanded irrigation by overpumping aquifers.
Lastly, the Party made a conscious decision to abandon self-sufficiency in soybeans and concentrate their agricultural resources on remaining self-sufficient in grain. The effect of neglecting the soybean in the country where it originated was dramatic. In 1995 China produced and consumed nearly 14 million tons of soybeans. In 2010 it was still producing only 14 million tons—but it consumed nearly 70 million tons, most of it to supplement grain in livestock and poultry rations. China now imports four-fifths of its soybeans.
Despite China’s herculean efforts to expand grain output, several trends are now converging that make it harder to do so. Some, like soil erosion, are longstanding. The pumping capacity to deplete aquifers has emerged only in recent decades. The extraordinary growth in China’s automobile fleet and the associated paving of land have come only in the last several years.
Overplowing and overgrazing are creating a huge dust bowl in northern and western China. The numerous dust storms originating in the region each year in late winter and early spring are now regularly recorded on satellite images. For instance, on March 20, 2010, a suffocating dust storm enveloped Beijing, prompting the city’s weather bureau to warn that air quality was hazardous, urging people to stay inside or to cover their faces when outdoors. Visibility was low, forcing motorists to drive with lights on in daytime.
China is now at war. It is not invading armies that are claiming its territory, but expanding deserts. Old deserts are advancing and new ones are forming like guerrilla forces striking unexpectedly, forcing Beijing to fight on several fronts. And in this war with the deserts, China is losing.
Overpumping, like overplowing, is also taking a toll. As the demand for food in China has soared, millions of Chinese farmers have drilled irrigation wells to expand their harvests. As a result, water tables are falling and wells are starting to go dry under the North China Plain, which produces half of China’s wheat and a third of its corn. The overpumping of aquifers for irrigation temporarily inflates food production, creating a food production bubble that eventually bursts when the aquifer is depleted. Earth Policy Institute estimates that some 130 million Chinese are being fed with grain produced by overpumping—by definition, a short term phenomenon.