What are the aspects of intensive cultivation in ancient China?

Intensive cultivation in ancient China is reflected in the following aspects:

1. Production tools: Spring and Autumn Period and Warring States Period-iron plow; Western Han dynasty-coupled plough (sowing tool); Sui and Tang Dynasties-Quyuanli

2. Farming method: the Spring and Autumn Period and the Warring States Period-ridge farming method (the most advanced farming method in the world at that time); Western Han Dynasty-Daitian Law

3. Water conservancy project: Dujiangyan (Warring States Period); Cao Qu, Bai Qu and Long Shou Qu (Han)

4. Irrigation tools: rollover (Three Kingdoms), trailer (Tang Dynasty), high-turnover trailer (Song Dynasty) and pneumatic waterwheel (Ming and Qing Dynasties).

5. Agronomic monographs: The Book of Fan Sheng Zhi in the Western Han Dynasty, The Book of Qi Yao Min in the Northern Wei Dynasty, The Book of Agriculture in Chen Fu in the Song Dynasty, The Book of Agriculture in Wang Town in the Yuan Dynasty and The Book of Agriculture in the Ming Dynasty.