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根据古城废弃、湖泊退缩、频降尘期等发生时代的相对一致性 ,确定了历史时期河西走廊沙漠化过程存在三次大发展时期 ,即南北朝、唐末五代和明清两朝 ,它们均对应近 2ka以来的气候干冷阶段 .认为清代中期河西走廊人口密度突破了干旱地带人口压力的“临界指标”且水资源利用率超过 4 0 %是晚近沙漠化土地迅速扩大的主要原因 .
According to the relative consistency of the era of the ancient city discarded, the lake retreated and the frequency of falling dust, the three major development stages of the desertification in the Hexi Corridor during the historical period are confirmed, namely the Southern and Northern Dynasties, the late Tang and the Five Dynasties and the Ming and Qing dynasties, all of which correspond to the past 2 ka The dry and cold phase of the climate.It is considered that the population density of Hexi corridor in the middle of the Qing Dynasty exceeded the “critical index” of the population pressure in the arid zone and the water resource utilization rate exceeded 40%, which was the main reason for the rapid expansion of the desertification land nearby.