杭州湾地区海平面控制下的地貌演化及其对新石器文化的影响

Under the background of global warming, sea level rise and frequent extreme climate events, how would human cope with and adapt to the changing environment are hot spot in the field of global change research. It is important to reconstruct the palaeoenvironment and extreme climate events on the typical delta area. This is also vital for exploring the relationship between human activities and geomorphological environment evolution. Hangzhou Bay with rich Neolithic culture relic is one of the first places where domesticated rice was originated. In addition, this area is characterized by frequent land-sea interaction during the Holocene. These contribute to an ideal area for studying the dynamics of sea level- geomorphological environment- extreme climate events and human adaption. In this project, sediment profiles in the archaeological sites (Kuahuqiao and Xiasun) located in the southern Hangzhou Bay, and natural profiles around the sites are collected as research materials. Through comparing the sediment sequence of the region, the project tries to construct a precise sedimentary stratigraphy, chronology framework, and multi-proxy sequence (including micropaleontological, geochemical and geophysical index). By investigating modern diatom-environment data set of regional tidal flat and estuary and establishing transfer function, the project will analyze the source of diatoms from sediment profiles, and reconstruct the palaeosalt and palaeo-tide level in this area during the Holocene. Based on that, the project will further examine the detailed geomorphological environment evolution, define the extreme climate events, and explore their influences on the Neolithic human being. This project will provide key evidences for the Holocene geomorphological environment evolution and relevant human adaption in the eastern China and establish a new quantitative approach for reconstructing the Holocene sea level change.

全球增温背景下，海平面上升、极端气候环境事件频发，人类如何应对，是全球变化研究的热点。开展典型三角洲地区古环境及极端气候环境事件重建，是探索早期人类活动与地貌演化关系的突破口。杭州湾地区是我国稻作农业的起源地之一，新石器文化丰富，全新世时期海陆环境变迁频繁，是研究海平面变化-地貌环境-极端气候环境事件及人类适应的理想场所。本项目选择杭州湾南岸的跨湖桥和下孙遗址及周边自然岩芯剖面，通过区域地层对比，建立准确的沉积地层序列和高分辨率年代标尺，进行生物、地球物理和化学环境代用指标建立。结合区域潮滩和入海口现代硅藻－环境数据的调查和转换函数研究，定量重建该地区全新世古盐度和古潮水位变化。综合分析杭州湾南岸地区精细的地貌环境演化过程，对极端环境事件进行厘定，深入探讨其对新石器史前人类的影响。该研究将为我国东部全新世地貌环境演化及人类适应研究提供核心证据，并为全新世海平面变化重建研究提供新的定量手段。