The Origin and Development of Rice Cultivation

点击翻译按钮获取中文摘要

New results were obtained on the origin of rice cultivation in China. Previous knowledge about the origin of rice cultivation was that the rice cultivation began in Yunan district at 5000 years BP.However, this research project revealed the birth place of the rice cultivation was the middle basin of the the Yangtze Rive especially the area of Hunan province and that the age of the beginning of rice cultivation was older than 12,000 years BP.The Hunan Province is located in the subtropical climate, however, in winter this region is attacked by the cold whether bringing snow. Our results showed that this cold climate in winter, especially during the Younger Dryas in Late glacial period caused the food crisis. This food crisis might be the important element for the people to shift toward cultivation. After that time, the rice cultivation expanded at 7000,5000 and 3000 years BP when the climate deteriorated. This means that the food crisis caused by the climatic deterioration was one of the important elements for the expansion and development of rice agriculture. At 5000 years BP,the urbanization occurred at the Liangzhu cultural area in lower basin of the Yangtze River, at the Qujialing cultural area in middle basin of the Yangtze River and at the Changdu plain in the upper basin of the Yangtze River. In this research project, we excavated the Longmagucheng site in the Chengdu plain and cleard that the huge oblong castle wall 1100m in long axis and 600m in short axis was constucted at 2500BC.The wall was constructed by the destruction of the evergreen broad leafed forest mainly composed by Quercus Cyclobalanopsis and Castanoposis. Houses with garden and canals existed in this fortified town, however, we could not find out the evidence of rice paddy field inside of wall. This urbanized town was declined at 1000BC by the climatic deterioration which mainly caused by the fluctuation of the monsoon.