China's success in increasing per capita food production.

China has to feed 20% of the global population with only about 5% of the planet's water resources and 7% of its arable land. With such limited natural conditions, however, China's grain production has increased from about 200 kg per capita in 1949 to about 400 kg in the early 1990s. Hunger as a social problem has largely disappeared after being prevalent in China for several thousand years with the rise and decline of dynasties. This achievement has been accompanied by a 2.5-fold increase in the population and a 4.5-fold increase in total grain production. Although total cropped land has increased slightly in some areas, land used for cropping has decreased from 0.18 hectare per capita in the 1950s to less than 0.1 hectare per capita today. Apparently, yield increase or improved land productivity is the major contributor to the increase of food production per capita. What are the major reasons for the unprecedented achievement in China's food production? Political decisions, good or bad, on land distribution and ownership changes, have caused unusual fluctuation in grain production. Technical progress, however, has maintained a long-term increasing trend. The semi-dwarf cultivars of rice and wheat, the use of heterosis in rice and maize, and the alleviation of salinized soil stress in the major grain-producing areas have all played significant roles in increasing China's food production capability.