西汉时期,地处北部边境的并州,是农耕经济区与游牧经济区交错相接的地区,也就成为了农耕民族与游牧民族交流、碰撞与冲突的前沿阵地,其人口来源复杂,人口数量极不稳定,其变化大致经过了快速发展、持续增加和快速减少这一过程,这一变化实则是西汉王朝经济和边防实力兴衰的晴雨表,折射出这个王朝综合国力由兴盛转向式微。 Western Han Dynasty, located in the northern border and the state, is the agrarian economic zone and the nomadic economic zone cross-linked areas, it has become a farming nation and nomadic ethnic exchanges, collisions and conflicts in the forefront of its complex source of population, the population of very Instability. The change has generally gone through rapid development, continued to increase and rapidly decreased. This change is actually a barometer of the rise and fall of the economic and frontier defense forces in the Western Han Dynasty, and reflects the shift of the overall national strength of the dynasty from prosperity to decline.