A Study On The Evolution Of The Geomorphology And The Relationship Between Man And Land In The Neolithic Period In The East Of Jianghuai

The east of Jianghuai Plain is located in the Lixia River Plain,which is in the north of the Yangtze River of Jiangsu Province,south of the waste Yellow River,west of the Beijing-Hangzhou Grand Canal,and east of the South Yellow Sea.Under the comprehensive effect of the Three Rivers(Yangtze River,Yellow River,Huai River)and the One Sea(Yellow Sea),this area gradually became landfall in the middle and later stages of the Holocene,and along with Neolithic culture emerged in the area and flourished to decline.Quaternary researchers have done environmental archaeological research on coastline changes,Holocene climate evolution,and the flat distribution of sites.However,there are few studies on how the ancient ancestors used and depended on the paleogeographic environment to carry out economic and cultural activities with regional characteristics.In this paper,we selected the Gangxi section of the Jianhu in Jiangsu Province(GX2 Section)and the famous Huai'an Qingliangang site for the analysis of paleoenvironmental indicators,establishes regional stratigraphic sequences,and combines the AMS14C dating results to obtain basic understanding of the sea level change and the landform evolution in this area.and analyze the land forming process of the study area under the comprehensive effect of "three rivers and one sea" in the Centennial scale.The important remains of the typical sites were selected to carry out research on the man-land relationship of the Neolithic Age in the east of Jianghuai Plain.And it is emphasized that the main economic activities of the Neolithic culture are promoted and blocked by different landform units(lagoons,salt marshes,shallow lakes,marshes and land).At the same time,combined with the spatial and temporal distribution patterns of the Neolithic sites and analyzes the source and direction of Neolithic culture in the east of Jianghuai Plain as well as the relationship with the paleogeographic environment.Since 8500 cal.a BP,the climate of Jianhu region in Jiangsu Province has undergone a process of partial warm-partial warm humid-partial cool dry.The corresponding vegetation evolution also experienced evergreen,deciduous broad-leaved mixed forest-evergreen broad-leaved forest containing deciduous broad-leaved trees-coniferous forest-coniferous and broad-leaved mixed forest.The evolution process of the geomorphic environment can be roughly considered to be in the 8500-7500 cal.a BP,the sea surface is continuously rising.The GX2 section is below the average tidal level.It is a shallow sea environment;7500-6800 cal.a BP,the rising rate of the sea surface is slower.The Huai River develops,and the terrestrial matters increases.The impact of seawater on the region weakened and the GX2 section is located in the upper part of the intertidal zone;6800-5800 cal.a BP,the coastline was stagnant in the Jianhu region and the GX2 section of the Jianhu was mainly located in the supra tidal zone and the lagoon develops.5800-4200 cal.a BP,the sea water has already withdrawn from the GX2 section of Jianhu region.And the lagoon gradually turns into a freshwater lake;4200-3800 cal.a BP,influenced by sediment deposition,the lake surface is reduced,and the water area is reduced to become a shallow lake-Marsh environment;3800-400 cal.a BP,the GX2 section of the Jianhu region is developed into a freshwater marsh environment.During the middle Holocene,the global sea level became stable,the coastline retreated eastward,the Huai River delta developed and the sand hill formation in Northern Jiangsu Plain,which isolated the influence of seawater.The area has mostly developed into a shallow water-lake and marsh environment,providing suitable living conditions and fishing and hunting resources for the ancient ancestors.It can be considered that the east of Jianghuai Plain is close to the Yellow Sea and is affected by the ocean,so it is not sensitive to the Holocene temperature fluctuations or climate events.Around 6000-4000 cal.a BP,the eastward migration of the coastline in the east of Jianghuai Plain and the development of the lake and marshland network environment have made it possible to migrate the northern and southern cultures,providing favorable geographical conditions.There are different channels for the spread of culture between the cultural northwards in the Taihu Lake area and the cultural southwards in the Haidai area.The culture of the Taihu Lake area was mainly in the narrow rivers of Nanjing and Zhenjiang,crossing the ancient Yangtze River,and then carrying the cultural factors of Ningzhen area to the Qingdun area along the coastline to form a gathering.Then,along the Sand hill coastline,another settlement is formed in the Funing area.The northern boundary of the site is the ancient Huai River basin.The northern part of the ancient Huai River is the distribution area of the Haidai Culture,and the Qingliangang Site may be a stronghold southward.The channel of cultural transmission may migrate southwards along the Grande Canale to the Zhoubeidun Site of Gaoyou,and eastward to Xinghua and Taizhou.Then they arrived at the Ningzhen area in the opposite direction of the Liangzhu Culture,which is spread northward.