论文部分内容阅读
渭河流域全新世古土壤S0 与黄土L0 之间的界限 ,是反映季风气候格局快速转变和土壤资源退化的标志。这个时期的气候干旱化和水土生物资源退化 ,促使流域上游游牧文化取代定居农业文化 ,从而造成土地利用方式的巨大变化。在历史上表现为游牧民族的南侵 ,迫使先周人从泾河中游黄土高原腹地向南迁移到关中盆地西部的周原 ,即“古公迁岐”。气候干旱化还造成河水断流、沙尘暴频繁发生、严重饥荒、社会动荡和商周之际朝代更替。这是我国北方半干旱区季风环境敏感带、人地关系演变史上的重要事件。通过综合分析黄土剖面土壤资源退化记录 ,和历史文献中水土生物资源退化的记录 ,结合已有的14 C、TL测年数据和新公布的夏商周年表 ,确定渭河流域全新世古土壤S0 与黄土L0 之间的界限为14 C年代 (30 30± 80aB P) ,历史纪年 115 0B C ,或者 310 0aB P 。
The boundary between Holocene paleosol S0 and loess L0 in the Weihe River basin is a sign of the rapid change of monsoon climate pattern and the degradation of soil resources. The climate aridification and the degradation of living resources during this period led to the substitution of the nomadic culture in the upper reaches of the basin for the settlement of agricultural culture, resulting in a great change in land use patterns. The southward invasion of nomads in history showed that the ancients were forced to migrate southward from the hinterland of the middle reaches of the Jinghe River to the western part of the Guanzhong Basin. Arid climate has also caused the river to turn on and off, dust storms occur frequently, serious famines, social unrest and the dynasties dynasties replaced. This is an important event in the evolvement history of monsoon environment-sensitive belt and man-land relationship in the semi-arid region of northern China. Based on the comprehensive analysis of records of soil resource degradation in the loess section and records of degradation of soil and water biological resources in historical documents, the 14C and TL dating data and the newly announced annual catalog of Xia Shang were used to determine the relationships between the Holocene paleosol S0 and loess The boundary between L0 is 14C (3030 ± 80aB P), historical record 115 0B C, or 310 0aB P.