淮河是一条对华夏文明具有重大意义的河流.但相较于黄河与长江流域,淮河流域的考古及古环境研究较为滞后.桥头遗址是淮河上游一处以石家河文化为主的重要遗址.本研究通过对桥头遗址区及其临近区域的地层调查和室内样品的测试分析,对该遗址生成前后的环境变化以及古洪水事件与遗址的存续关系等展开了研究.研究发现:桥头遗址生成前大约在8.1~4.6 kaBP(9.1~5.4 cal.ka BP),遗址所在至少方圆2 km的范围区一直被湖沼所覆盖;4.6 kaBP(5.4 cal.kaBP)以后,温暖湿润的气候、地势较高的湖沼相沉积高地以及紧邻作为遗址水源地的母子河等优越的自然环境,吸引了先民来桥头区域生活;4.0kaBP的气候异常事件、3.5 ka BP(3.9 cal.ka BP)的气候波动所带来的洪水灾害和3.2 ka BP(3.6 cal.ka BP)的淮河改道等自然环境的频繁变动,使得石家河文化以后的1000年时间内遗址区不适宜人类居住.3 kaBP(3.3 cal.ka BP)之后,桥头遗址所在区域的气温逐渐升高变暖,先人再次在此定居;2.5 kaBP(1.8 cal.kaBP)后,气候的剧烈波动、洪水的频繁泛滥再次威胁到人类在桥头遗址区域生产生活,先人从此地再次迁徙.
Palaeoenvironmental background of Qiaotou Site in Chushandian reservoir area in the upper reaches of Huai River
The Huai River is a river of great significance to the Chinese civilization.However,com-pared with researches in the Yellow River and Yangtze River basins,archaeological and palaeoenviron-mental research in the Huai River Basin has been relatively lagging behind.Qiaotou Site is an important site of the Shijiahe culture in the upper reaches of Huai River.This paper studied the environmental changes before and after the formation of Qiaotou Site,as well as the relationship between the palaeoflood events and the survival of the site,through stratigraphic investigations and testing and analyses of indoor samples from the Qiaotou site area and its adjacent areas.The results showed that at least 2 km around Qiaotou Site was covered by lakes or marshes during 8.1~4.6 ka BP(9.1~5.4 cal.ka BP)before the formation of Qiaotou Site.After about 4.6 ka BP(5.4 cal.ka BP),the ancestors were attracted to live in this region by its excellent natural environment,such as the warm and humid climate,highland terrain,and water source—Muzi River adjacent to the site's,etc.Unfortunately,this region became unsuitable for human habitation in the millennium after the Shijiahe culture due to the frequent environmental changes such as climatic anomalies(4.0 ka BP),floods caused by climatic fluctuations(3.5kaBP,i.e.3.9 cal.ka BP),and the diversion of the Huai River(3.2 ka BP,i.e.3.6 cal.ka BP).After 3 ka BP(3.3 cal.ka BP),the ancestors settled here again as the temperatures in the Qiaotou site area gradually in-creased and became warmer.However,the ancestors had to leave this area again after 2.5 ka BP(1.8 cal.ka BP),as the highly fluctuating climate and frequent floods threatened the human survival.
Upper reaches of Huai RiverQiaotou Sitepalaeoenvironmentpalaeoflood