WORLD HISTORY

Detailed explanation-1: -Political stability and a growing labor force led to economic growth, and people opened up large areas of wasteland and built irrigation works for expanded agricultural use. As land-use became more intensive and efficient, rice was grown twice a year and cattle began to be used for plowing and fertilization.

Detailed explanation-2: -Moreover, multi-seasonal rice varieties and kapok were adopted and initially planted in the warmer South-eastern REgion and then in the Yangtze River region. Peanut, potato, sweet potato, tobacco, and corn were initially introduced as foreign crops in the South-eastern region and were later adopted across China.

Detailed explanation-3: -Ancient Chinese began farming rice over 9, 000 years ago. Farming made life easier because people no longer had to travel to hunt animals, but could grow their food where they lived. Rice and millet were the two main crops grown in Ancient China. Rice paddy (field) flooded from river.

Detailed explanation-4: -Construction of the Dujiangyan irrigation system began in the 3rd century B.C. This system still controls the waters of the Minjiang River and distributes it to the fertile farmland of the Chengdu plains.