阶地平原
阶地平原-
史前人类的居住方式大致经历了树栖、天然穴居、季节性人工营地、定居性人工聚落等几个阶段，最终实现了由林地、山地到阶地平原的居住地转移。
The living patterns of prehistoric humanity went through living on trees , in caves , on seasonal camps , on seasonal artificial camps , on settlements and finally achieved the changes from forest land to mountainous region and to terrace plain .