Please talk about the favorable natural conditions for economic development in the south in combination with the history from the late Tang Dynasty to the Song Dynasty.

Land conditions: there are famous plains in the middle and lower reaches of the Yangtze River and Chengdu Plain in Sichuan Basin in the south. The plain has a vast area and fertile soil, which is suitable for agricultural production.

Climatic conditions: The annual temperature in the south is above zero, twice a year in the north of the Yangtze River and three times a year in the south of the Yangtze River.

Compared with the north, the south has dense river networks and convenient irrigation. At the same time, abundant precipitation is beneficial to agricultural production.

The illumination time is also longer, which is beneficial to crop growth.

There is little frost in winter.