中古时期桑干河流域农牧环境的变迁——兼论北魏为何定都平城

On the Changes of Agriculture and Animal Husbandry Environment in Sanggan River Valley in Middle Ancient Times——Discussing the Reason Why the Northern Wei Dynasty Makes Pingcheng Be Its Capital at the Same Time

汉末以来,桑干河(灅水)流域内的经济形态存在一定的差别:桑干河南,在不同时期保留或恢复了不同程度的农耕经济,北魏时期迁徙畿内的农耕居民多安置于此地;而在其北部,自汉末以来就完全畜牧和狩猎化,北魏时期更是迁徙了大批游牧、渔猎民族于此,并修建了规模宏大的苑囿,更适合作为牧民和猎手的"国人"居住。所以在北魏时期,形成了"灅北地瘠"的经济格局。在代北地区的众多城市中,平城位于阴山以北拓跋鲜卑故地进入桑干河流域的三条主要陉道中居中者,地处灅北的国人聚居区,便于沟通草原游牧社会与中原农耕区域,控制整个桑干河流域乃至华北地区,所以自猗卢时代即开始经营,最终定都于此。

Since the Late Han Dynasty, there have been the differences of economic forms in the Sanggan River Valley. In the south, farming economy is maintained or recovered in different periods and the farmers immigrated in the period of the Northern Wei settled. While in the north, it has been the complete animal husbandry economy since the Late Han Dynasty and the nomadic, fishing and hunting tribes settled. As a result, the economic structure of infertile north Sanggan River is formed in the Northern Wei Dynasty. Among the cities in Daibei region, Pingcheng lies in the north of Yinshan Mountain, the middle of the three roads for Xianbei tribe to enter Sanggan River Valley. At the same time, it is also the settlement of immigranted Xianbei tribe. Therefore, it is convenient to communicate farming and animal husbandry economy and to control the whole valley and even the whole north. Because of these, it begins to be built since Yilu and finally becomes the capital.