Bill Taylor of the "US Policy on China and the Rest of the World" Group has asked:  "Can China Feed Itself?"
It depends.
More specifically, it depends on the sustainability of a delicate balancing act which Beijing is performing with major  social forces.

The underlying tectonics in China are, naturally enough, all interdependent:

o    As a matter of state policy, China is committed to moving 15 million people per year from rural locations to cities
=> This rate of human relocation requires 8% economic growth for the central, provincial and municipal governments to sustain, hence the talisman-like status of 8% growth in Chinese economic plans and reports
=> On the positive side of this massive (and planned) demographic shift of population from the countryside to cities is potential environmental benefit since urban habitation is, per capita, a lighter load on the environment than rural habitation
=> On the negative side is the potential drag on perceived ‘agricultural security’ and ‘agricultural self-sufficiency’ in China unless the fact of fewer farmers year by year is consistently offset by increasing agricultural efficiency per hectare year by year
=> The imperative to achieve increasing annual agricultural efficiency helps explain China’s fervent embrace of agricultural biotechnology. On the flipside, this imperative is seriously undermined by patterns of municipal corruption in the expropriation and development of former farmlands.

In the background of all these interrelated trendlines is the ticking sound of China’s extreme demographics. As a result of China’s ‘one-child’ social engineering, China will soon (withinn decades) be at the extreme end of the global spectrum of age-imbalance with a narrow base of young people trying to support a top-heavy number of old people.

The key question is obviously will the government have managed to have delivered enough of a virtuous cycle of economic/enivonmental benefit for it to be sustained even when the demographic ‘graying’ starts serious downward pull on this house of cards.

Lost in all this is what individual citizens, with changing life-horizons and expectations, think of these state-managed forces affecting their lives. More important is what they will do if enough of them feel the same way. Social stresses on the one-year anniversary of the Sichuan earthquake don’t inspire confidence that the CCP will be well-equipped for this wild card in the deck.

No wonder the Zhongnanhai leadership shows some nervousness about the growing influence of China’s ‘netizens.’