The nomadic economy of agricultural economic dependence determines the families of northern grassland in South and Central Plains area, active economic cultural exchanges, while agricultural economy on animal products have a certain demand. 游牧经济对农耕经济的依赖性决定北方草原地区诸族不时南下,主动地与中原地区进行经济、文化往来,而农耕经济对畜产品亦有一定的需求。