Why is Wulanbu called Deshan Chifeng?

Mongols and China divide and rule. According to the Life Encyclopedia, Wulanbu series was changed to Deshan Chifeng in Qing Dynasty, and the policy of supporting the people by borrowing land was implemented. The number of Han immigrants in the farming-pastoral ecotone between Mongolia Plateau and the Great Wall increased, and the Qing Dynasty began to set up counties in areas where immigrants concentrated. The names of counties were mostly related to Chinese, so Wulanbu series was changed to Deshan Chifeng.