What are the major developments and changes in the economy of the Song Dynasty compared with that of the Tang Dynasty?

The economy includes agriculture, handicrafts and commerce.

Agriculture: From the mid-Northern Song Dynasty, China began to introduce Zhancheng rice from Annan (now Vietnam) (a kind of rice with high yield and strong adaptability to fields, which is still one of the main rice varieties in the Mekong Delta), which greatly increased the rice yield in China and the per capita ration was higher than that in the Tang Dynasty. With the unprecedented prosperity of overseas trade, the commercialization of agricultural products, including grain, has greatly improved. Due to the increase of rice area and yield, the economic center of China moved south, which was completed in the Southern Song Dynasty and China.

Handicraft industry: ceramic production developed greatly. In the Northern Song Dynasty, there were Ru, Guan, Jun, Ge and butyl five kilns, among which white porcelain technology was mature; At the end of the Southern Song Dynasty, cotton-padded clothes and trousers became the necessities of people's life, indicating that the cotton textile industry had made great development.

Commerce: Since the Northern Song Dynasty, the separation between shops and markets has accelerated, and a "small market" has emerged (there was a night market in the Tang Dynasty). The government's control over commerce has been reduced, and the market economy is much looser than that in the Tang Dynasty. However, in the Tang Dynasty, the boundaries between commercial areas and residential areas were strict, and the market opening hours were strictly limited. The variety of goods has increased; The earliest paper money "cross" appeared; Foreign trade was unprecedentedly active, and the Maritime Silk Road was opened.

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