1. After the Spring and Autumn Period, the Warring States and the Qin Dynasty unified the six countries, the original years of war brought great harm to the people. However, Qin Shihuang did not implement the policy of recuperation, but let a large number of people guard the northern border, build the Great Wall, build the Epang Palace and build the Mount Li Qin Mausoleum, which hindered the development of production. However, because Guanzhong Plain was the political and economic center of the whole country at that time, the terrain was very flat and fertile, so it was still a well-deserved land of abundance. However, with the passage of time, it has been found that the Chengdu Plain, located in this basin on the edge of Guanzhong Plain, has better conditions, richer water sources, more fertile soil and better climatic conditions.

2. In Sichuan Basin, where there is water, there are people, and where there are people, there is water. Chengdu Plain is located in the southwest, with low altitude, easy storage of natural rainfall and abundant natural water sources, which is suitable for human habitation. In ancient times, grain output was a key factor to measure the condition of a place. On the other hand, because many rivers pass through Chengdu Plain, fertile soil will be left in flood season.

In the era of cold weapons, man-made disasters are more terrible than natural disasters. Sichuan is surrounded by mountains and it is very inconvenient to enter Sichuan. The poet Li Bai's poem Shu Dao Nan illustrates this point well. The biography of the Three Kingdoms and Zhuge Liang also mentioned that Yizhou was in peril, fertile land was thousands of miles away, and Gaozu was the emperor. Special natural conditions have created relative peace in Sichuan, thus giving Sichuan better development conditions.

4. With the construction of Dujiangyan Water Conservancy Project by Li Bing and Zi Erlang, the prefects of Shu County in Qin Dynasty, its huge benefits greatly promoted the development of Chengdu Plain. At that time, there were floods and droughts that followed people, and there was no famine, so it was called the theory of abundance, which meant that the situation of floods and droughts was based on people's will, agricultural production was better, the local people's lives were guaranteed, and there was no famine, so people at that time called it the land of abundance. Therefore, Sichuan gradually became the main grain supply base and the main source of tax revenue of the central dynasty, thus becoming a de facto land of abundance.

Later, in the Three Kingdoms period, Kong Ming rewarded farming, developed production and built water conservancy projects. This is a great impetus to the plain agriculture in Chengdu. The phenomenon of "not picking up the remains and not closing the door at night" has been realized in the territory, and the reputation of a land of abundance has been spread. In the heyday of Chengdu in the Tang Dynasty, a poem by Li Bai blossomed in Chengdu in nine days, and thousands of families were drawing pictures. Every grass and tree was as beautiful as a cloud, which was not available here in the Qin Dynasty. Chengdu's position as a land of abundance has been consolidated. Gradually, the land of abundance became synonymous with Sichuan.