河南新密溱水流域全新世人类文化演化的环境背景研究

PRELIMINARY RESEARCH OF ENVIRONMENT ARCHAEOLOGY IN ZHENSHUI RIVER,XINMI CITY,HENAN

溱水流域新石器至夏商时期人类文化发达,且持续发展,是中原地区乃至全国新石器至夏商时期人类文化最为发达的地区之一。本文在详细野外考察和多个地层剖面分析基础上,初步阐明了区域地貌特征及演化历史。对区域内的柿园仰韶遗址外的自然沉积剖面(34°29.409′N,113°36.933′E)进行了连续采样,并对样品进行了^(14)C年代测定和粒度、磁化率、孢粉等古环境指标分析,结合考古遗存资料,探讨了区域全新世气候演变历史。在上述古环境研究基础上,分析了区域全新世环境与人类文化演化之间的关系。结果表明:流域在地形上,处于嵩山以东至黄淮平原以西的黄土丘陵台地地形区。溱水流域共发育了3级河流阶地:第三级阶地形成于晚更新世末期;第二级阶地形成于大致6000~4000cal.aB:P.时期,下游阶地形成时代较上游早;第一级阶地形成于历史时期晚期。溱水流域全新世早期(8500~7000cal.aB.P.)气候的暖湿程度与现在相当,仰韶文化时期(7000~5000cal.aB.P.)的气候是该地区全新世最为暖湿的时期,龙山文化时期(5000~4000cal.aB.P.)以来气候的暖湿程度呈波动下降,4000cal.aB.P.以后气候逐渐变干凉。整体上较为暖湿的气候是该地区全新世人类文化持续发展的有利条件。广阔平坦的多级黄土台地和第三级阶地以及广泛分布的黄土沉积物质为新石器以来逐渐发展的旱作农业提供了有利的地貌和土地资源条件。仰韶早期及之前的人类文化遗址分布在第三级阶地和地势更高的黄土台地之上;仰韶中期以后,由于区域人口的增加和农业的发展,人类聚落有向沿河阶地和下游地区发展的趋势。

Zhenshui River,southeast of Song Mountain,is the fourth branch of Ying River in Xinmi City,Henan Province.It locates in the center of central plain＇s Neolithic culture area.It has large number of Neolithic culture sites in this and its＇ adjacent region,and is also one of the important civilization cradles in China.Shiyuan profile（34°29.409＇N,113°36.933＇E; Elevation of 132 meters）,with depth of 4.22 meters and 211 samples separated in 2cm,locates on the second terrace of Zhenshui River.To investigate the effect of environment changes on the culture transition,the environment records from multiple proxies including grain size,magnetic susceptibility,pollen and radiocarbon dating are correlated with the Neolithic cultural records in Zhenshui River region.It has been dated by 14C radiocarbon that the results of samples sy18（386-388cm in depth）,sy74（274-276cm in depth）,sy117（188-190cm in depth）,sy177（68-70cm in depth）,sy189（44-46cm in depth）,and sy205（12-14cm in depth）are 7800±60cal.aB.P.,6045±45cal.aB.P.,5455±40cal.aB.P.,3560±40cal.aB.P.,3330±40cal.aB.P.,and 2775±40cal.aB.P.,respectively. The profile is separated into 4 sections,with the date 8000-5000cal.aB.P.,5000-4000cal.aB.P.,4000-3000cal.aB.P.,and 3000cal.aB.P.to now in each section.From the analysis of the grain size and magnetic susceptibility results,there are three terraces formed in Holocene period：The third terrace is formed in late Pleistocene,and people used to live on this terrace through the Neolithic time.The second terrace is formed around 6000cal.aB.P.in the lower reaches,but it began to cut down around 4000cal.aB.P.from the Xiangshui fall in the middle reaches.The third terrace is formed in late historical period,and it has been also documented that the climate is almost the same warm and wet as present in the Early Holocene（8500-7000cal.aB.P.）.The warmest-wettest phase of the whole Holocene is the period（7000-5000cal.aB.P.）in this region,and it changed to cold-arid around 4000cal.aB.P.During 3900-3600cal.aB.P.,the climate is warm and dry and has a trend to be drier in this period.In the time of Peiligang Culture（8500-7000cal.aB.P.）,people come down to the loess plateau and the third terrace of Zhenshui River from the hill,and live on hunting and dry farming.A large number of sites are found in Yangshao Culture period（7000-5000cal.aB.P.）.The population is larger than before and dry farming plays a more important role in people＇s life.People have to expand their space to feed more persons.As the result of this reason,they gradually migrate down to the middle and lower reaches.In the period of Longshan Culture（5000-4000cal.aB.P.）,settlements are classified and the population gets more centralized than ever.Guchengzhai site（5000-4000cal.aB.P.）was found a center city as the result of population centralization.From 4000cal.aB.P.on,people moved down and gradually lived on the east plain.