What are the advantages of China's ancient agricultural output compared with the West?

The output per unit area of ancient agriculture in China was much higher than that in ancient and medieval Western Europe. The ratio of grain harvest to sowing in western Europe is 4~5 times according to Rome Cromellan book, and 3 times according to13rd century British Henry's agricultural book. According to Qi Yao Min's Book, in the 6th century, the harvest of millet in China was 24 ~ 200 times that of sowing, while that of wheat was 44 ~ 200 times that of sowing. According to the Book of Supplementing Agriculture, the highest yield of rice in Jiahu area in the late Ming and early Qing dynasties can reach 4-5 stones, and the yield per mu is 901~126 kg, which is higher than that in California. The land productivity of ancient agriculture in China undoubtedly reached the highest level in ancient society.