【作者】 徐利斌；

【导师】 孙立广；

【作者基本信息】 中国科学技术大学 ， 环境科学， 2009， 博士

【摘要】 考古遗址地层是研究古代社会人类活动及其相关环境变化的良好载体之一。考古遗址地层研究对考古器物的依赖性较小,并且时间上具有连续性,在研究人类活动在不同历史时期的变化、古代社会的发展和更替,尤其是在探讨遗址地区的气候环境变化及其对人类活动、社会发展的影响等方面,延伸了文物考古的空间,正发挥着独特的作用。安徽蒙城尉迟寺遗址地处淮北平原中南部,是黄淮地区重要的新石器时代聚落遗存中心。本文利用安徽蒙城尉迟寺遗址采集的YC1古文化层剖面,在传统考古方法对尉迟寺遗址古文化研究结果的基础上,以沉积学、孢粉学、地质学、地球化学、古生态学、环境污染学等多学科交叉的理论和方法为指导,依据沉积物的粒度、孢粉、有机碳及其同位素、氨基酸、地球化学元素以及铅同位素等指标的分析和研究,并结合多元统计分析的数学处理方法,对尉迟寺遗址历史时期的各种人类活动、气候环境变化及其相互之间的关系,进行了综合研究,主要结论如下:（一）通过对尉迟寺遗址古文化层中19种化学元素的聚类分析、主成分分析以及相关性分析,得出P、TOC、Cu、Ca、Mn、Zn、Sr、Na、可溶性Sr和Ni在文化层中的波动主要是由人类活动引起的,并且以此为基础提取的第一主因子（Factor1）代表了尉迟寺遗址古文化时期的人口数量变化,可以反演尉迟寺遗址距今5050到4000年间的人口数量变化历史。Factor1的结果显示,文化更替的时候（包括尉迟寺遗址大汶口文化第一阶段、第二阶段、第三阶段以及龙山文化之间的更替）,均是尉迟寺遗址地区人口数量较少的时候;距今4400年前开始的龙山文化,其人口数量一直在减少,直到其消亡。（二）统计分析结果表明,Al、Fe、Mg、Si、K和Ti在古文化层中的波动主要是受气候环境因素控制,主成分分析提取的第二主因子（factor2）是夏季风强度的良好替代指标,其结果与粒度、孢粉分析的结果相一致。尉迟寺遗址地区在5050～4400 cal.yr.BP间,夏季风较强并且相对平稳,气候相对温暖湿润;在4400～4000 cal.yr.BP间,夏季风明显减弱,气候进入相对寒冷干旱时期。距今4400年左右发生的气候突变事件,标志着尉迟寺遗址气候由暖湿向干冷转变。（三）在利用古文化层进行古气候识别时,要考虑人为影响因素,避免直接使用第四纪地质学的通用研究方法,应有选择地采用古气候代用指标来正确地判断古文化时期古气候与古环境地变化。本文没有选择尉迟寺地区受人为影响较大的Ca、Sr、Na、Mn等作为气候代用指标的参数,而选择了受人为影响较小的Al、Fe、Mg、Si、K和Ti等参数来重建古气候,所得结果与其他分析方法的结果一致,并且与区域气候变化有很好的对应性。（四）尉迟寺遗址地区各个不同文化阶段的人口数量与夏季风强度有较好的相关性:夏季风越强,人口数量越多,反之亦然。原始社会的发展与气候有着紧密的联系,并且恶劣的气候条件是原始文化迁徙或者消亡的重要原因。人口数量、氨基酸以及孢粉研究均显示,尉迟寺遗址的龙山文化并不是由当地的大汶口文化发展而来的,而是由北方的龙山文化迁徙而来的。（五）有机碳同位素结果显示,尉迟寺遗址古文化时期的种植业生产以C₃（水稻）、C₄（粟、黍）作物混种为主。从大汶口文化初期到龙山文化中后期,种植粟、黍的比例有缓慢升高的趋势,但是在龙山文化末期,当地种植的水稻比例明显升高。由于相对干冷的气候可能导致龙山文化末期水稻大幅减产,这可能是尉迟寺遗址龙山文化消亡的重要原因之一。（六）YC1剖面中的Hg研究显示,文化层中的Hg主要受大气沉降影响。在5050～4550 cal.yr.BP期间,YC1剖面中的汞的累积速率相对较低,并且主要是受气候控制:气候越冷,剖面中汞的累积速率则越高;在4530～4000 cal.yr.BP,YC1剖面中汞的累积速率显著升高,此时气候已经不是影响剖面中汞的累积速率的主要因素,人类活动已经成为第一因素,古代人类原始金属冶炼的规模直接决定了剖面中汞的累积速率。距今4500年前后Hg的显著上升,标志着中华文明已经进入了铜石并用时代。铅同位素证据也表明,尉迟寺遗址剖面中的Pb很可能来源于中国南方地区（云南、四川、湖北、湖南或广东）的铜矿开采及其相关冶炼,与商周早期青铜器的铜料来源研究结果一致,间接说明了尉迟寺遗址距今4500年左右Hg的突然升高和冶金文明的发展有关。本文通过古遗址地层中系列生态和地质地球化学指标的测定,应用数理统计方法,尝试反演了尉迟寺遗址古文化时期的人口数量变化,探讨了古文化时期的气候环境变化以及气候变化与文化发展的关系,并且指出了利用遗址地层研究古气候时代用指标该如何选择的问题。另外,通过大气传输重金属的研究,给出了中国从石器时代进入铜石并用时代的自然科学证据,而不再仅限于出土文物的统计结果,丰富了我们对中国早期冶金文明发展史的认识。在未来的考古研究中,生态地质学方法将发挥重要的作用。更多还原

【Abstract】 Sediments of archaeological sites are good materials to study ancient human activities and its corresponding environment.And they are playing an increasingly important role in the study of ancient human activities,ancient social development and subrogation,paleo-climatic and paleo-environmental changes and their impacts on human activities,etc.,due to its low dependence on archaeological remains and temporal continuity.The Yuchisi Site,which is in Mengcheng county of Anhui Province,central south of the Huaibei Plain,is an important gathering site for people between Yellow River and Huaihe River during the Neolithic period.A sediment profile named as YC1 was collected in Yuchisi Site,and analysis,including grain size,pollen-spore assemblage, total organic carbon and its isotope,amino acid,geochemical elements and lead isotope were performed on the samples.Combined with the results of traditional archaeological studies in Yuchisi Site,different human activities,climate changes,as well as their relationship were studied under the guideline of theories and methods of sedimentology,palynology,geology,geochemistry,paleoecotogy.Main conclusions are listed as following:（1） Based on the results of cluster analysis,principle component analysis and correlation analysis,we found that the variation of P,TOC,Cu,Ca,Mn,Zn,Sr,Na, Ni and soluble Sr in the cultural layers were conducted by the human activities.The Factorl extracted by principle component analysis could represent the population fluctuation during cultural periods,from 5050 to 4000 cal.yr.BR The result of Factorl shows,cultural subrogation（including the subrogation in interior Dawenkou Culture in Yuchisi Site） was well corresponding to decreased population in Yuchisi Site;since the beginning of Longshan Culture at 4400 cal.yr.BP,the population went on decreasing,until the end of it in Yuchisi Site.（2） The statistical results indicated that the variation of Al,Fe,Mg,Si,K and Ti in cultural layers was mainly affected by climate,and the Factor2 extracted by principle component analysis was a good index of Asian Summer Monsoon,which confirmed by the grain size and pollen analysis.From 5050 to 4400 cal.yr.BP,the Asian Summer Monsoon was relatively stable and strong,and the climate was warmer and more humid;From 4400 to 4000 cal.yr.BP,Asian Summer Monsoon turned weaker,and the climate was cooler and drier.The climatic event happened at 4400 cal.yr.BP,indicated the climate of Yuchisi Site turned from warm and humid to cool and dry.（3） The human impact factors should be considered when we study the climate changes on archaeological sediments.We should avoid to use the common proxies from Quaternary Geology directly,but select the proxies less influenced by human activity to reconstruct the paleo-climate and paleo-environment correctly.In this study, we didn’t use the proxies,such as Ca,Sr,Na,Mn,which were largely affected by human activities in Yuchisi Site,but selected Al,Fe,Mg,Si,K and Ti to reconstruct the paleo-climate.The results are quite consistent with those by other methods,and have good relationship with the regional climate change.（4） The population of Yuchisi Site had good correlation with the summer monsoon:the stronger the summer monsoon,the larger the population,and vice versa. The primitive social development had close linkage with the climate,and the bad climatic condition was one of the most important reasons which led to the end of primitive culture.The results of population,amino acid and pollen-spore analysis, indicated that the Longshan Culture of Yuchisi Site was not developed from local Dawenkou Culture.（5） Stable carbon isotope compositions in organic matters showed that agriculture of Yuchisi Site was the mix farming of C₃ plant（rice） and C₄ plant（millet）.From the beginning of Dawenkou Culture to the mid-late Longshan Culture,the proportion of cultivated millet slowly increased.But at the end of Longshan Culture,the proportion of cultivated rice obviously increased.The large reduction of agricultural production which may be led by the cooler and drier climate,might be one important reason for the end of Longshan Culture in Yuchisi Site.（6） Mercury variation in the YC1 profile was mainly affected by atmospheric deposit.Mercury accumulation rate was low before 4550 cal.yr.BP,and was mainly affected by climate:the cooler the climate,the higher the mercury accumulation rate in the profile.From 4530 to 4000 cal.yr.BP,Mercury accumulation rate was high,and the climate was not the dominate factor any more,but the ancient human activity was. The shift of mercury accumulation rate happened at about 4500 cal.yr.BP,indicating the coming of Chalcolithic Period in China.The results of lead isotope composition also showed that the lead in the cultural layers of Yuchisi Site likely came from the copper mining from South China（Yunnan,Sichuan,Hubei,Hunan or Guangdong Province） and its smelting,which was corresponding to the source of bronze material of early Shang and Zhou Dynasties.It also indicated the shift of Hg at about 4500 cal.yr.BP in study site was correlated to the development of metallurgical civilization.Based on the analysis of ecological and environmental indexes,and the use of statistical methods,this paper reconstructed the population variation of paleocultural periods of Yuchisi Site,discussed the climate change and the relationship between climate and cultural development,and suggested how to select climatic proxy when studying the archaeological sediments which may be helpful in the future study of environmental archaeology.In addition,the study of heavy metal transported by atmosphere provided natural evidence for the entrance of Chalcolithic Period in China, which was only proved by the statistical result of archaeological relics before,and this finding has enriched our understanding of the developmental history of Chinese metallurgic civilization.The eco-geological methods will play an more and more important roles in the future archaeological research.更多还原