摘要
全新世气候变化一直是科学界关注的热点问题,尤其是罗布泊地区多次大规模的环境变化导致小河文明和楼兰文明等古文明的消失。笔者等通过对叶尔羌河流域的阿克奇河左岸黄土剖面系统采样和粒度、磁化率及年代学测试,重建了该地区5 ka BP以来的古气候环境,并在此基础上分析了昆仑山北区黄土沉积记录的古气候环境与塔里木河下游罗布泊地区小河文明之间的关系。研究结果显示4.5~3.58 ka BP,昆仑山区次生黄土快速堆积,气候较湿润,降水量较多,塔里木河上游水源充足,为下游罗布泊地区提供了大量水资源,也为小河文明的孕育和初期发展奠定了坚实基础;3.58 ka BP以后,昆仑山区的剖面沉积物由次生黄土转为风成黄土,显示气候开始转向干冷,因降水量减少导致流入到罗布泊地区的有效水资源逐步减少,罗布泊生态环境开始恶化,小河文明开始衰退,直至消失。因此小河文明的孕育与昆仑山区全新世湿润期气候有着非常密切的联系。
Objectives:Holocene climate change keeps being a concern of the academic circles.Especially,multiple large-scale environmental changes in Lop Nur region have led to the disappearance of ancient civilizations as Xiaohe civilization and Loulan civilization.Methods:In this paper,Based on the systematic sampling of the loess profile on the left bank of the Akeqi Riverin the Yeerqiang River basin at the north piedmont of the Kunlun Mountain and then grain size,magnetic susceptib ilityand chronology testing,this paper reconstructs the paleoclimate environment since 5ka BP,and analyzes the relationship between the paleoclimate environment recorded in the loess deposit at the north piedmont of the Kunlun Mountain and the Xiaohe civilization in the Lop Nur area in the lower reaches of the Tarim River.Results:The results show that during 4.5~3.58 ka BP,secondary loess accumulates rapidly at the north piedmont of he Kunlun Mountain,the climate is gradually humid,the rainfall and ice—snow melting water increase,and the water source in the upper reaches of the Tarim River is abundant,which provides a large amount of water resources for the lower reaches of Lop Nur area,and lays a solid foundation for the gestation and initial development of the Xiaohe civilization.After 3.58 ka BP,the sediment at the north piedmont of the Kunlun Mountain changed from secondary loess to eolian loess,and the climate began to turn to dry and cold.The decrease of precipitation led to the gradual decrease of available water resources flowing into Lop Nur,and the gradual deterioration of Lop Nur ecological environment,which finally caused the decline and disappearance of Xiaohe civilization.Conclusions:The emergence of Xiaohe civilization is closely related to the Holocene humid climate in the north piedmont of the Kunlun Mountain region.
作者
殷志强
秦小光
张磊
李康康
彭超
YIN Zhiqiang;QIN Xiaoguang;ZHANG Lei;LI Kangkang;PENG Chao(China Institute of Geo-Environment Monitoring,Beijing,100081;Institute of Geology and Geophysics,Chinese Academy of Science,Beijing,100029;Geological Survey Center of the Xinjiang Production and Construction Corps,Urumqi,830002;China University of Geosciences(Beijing),Beijing,100083)
出处
《地质论评》
CAS
CSCD
北大核心
2022年第4期1523-1529,共7页
Geological Review
基金
国家重点研发计划项目(编号:2018YFC1504704)
国家自然科学基金资助项目(编号:41977258)
中国地质调查项目(编号:121201014000169003)的成果。
关键词
全新世湿润期
黄土沉积
水资源
小河文明
昆仑山区
Holocene humid period
loess deposit
water resource
Xiaohe civilization
north slope of the Kunlun Mountain
