China Races to Reverse Falling Grain Production:

The rapid urbanization of China is eating up the land of millions of farmers. Millions more have stopped growing grain because it is not profitable. The resulting shift in the Chinese countryside has left government leaders worried about China's ability to feed itself and prompted an emergency campaign to curb land losses and increase grain output.

In an era of global trade, many economists find the political fixation on grain outdated. But it underscores the historic resonance of food security in China, where 30 million people died in the famines of the Great Leap Forward and where 1.3 billion people must be fed with only 7 percent of the world's arable land....

China has been increasing its imports and tapping into grain reserves. It is already the leading buyer of American soybeans. This year, for the first time in five years, China will import wheat. The political ramifications clearly worry China's nondemocratic leadership, even if many economists say imports are logical in a global economy.

"This isn't only an economic issue," said Robert Ash, a University of London economics professor with a specialty in Chinese agriculture. "China in a general sense doesn't want to be dependent for such a fundamental good. But, really, China doesn't want to be dependent on the United States."

(Emphasis mine). So in other words, all that blather about how much arable land China has is just blather.