At the end of the Western Han Dynasty, many people moved to the Yangtze River. Why?

During the Han dynasty, the long-term war in Guanzhong area greatly damaged the economic development.

2. The rapid population growth in Guanzhong has caused population problems and restricted economic development;

3. Long-term over-exploitation, serious soil erosion;

4. In the late Western Han Dynasty, the weather in China tended to be cold, and natural disasters occurred frequently in Guanzhong area;

At that time, there were few wars, fertile soil and suitable climate in Jiangnan area.