Pollen Assemblage Of Different Vegetation Types And Its Use In The Reconstruction Of Paleo-vegetation In Anyang Area

Anyang,as the ancient capital of late Yin Shang Ruins,has existed for more than 3,000 years.The study of Paleo-vegetation of Anyang area is important to understand the human activity in the past and its impact on vegetation and climate,and also is the essential components of the environment Archaeological of Anyang areas and Cultural Studies of Yin Ruins.In order to understand the environmental background of the occurrence of Yin Shang culture in Anyang area,we collected 122 surface samples and 29 paleo-soil samples which came from the layer just below the layer of yinshang sites in Anyang area.The results of pollen analysis of these samples will not only be helpful to reveal the background environment of occurrence Yin Ruins culture in Anyang area,so as tounderstand YinShang Culture well,but also can provide a theoretical and basis data for understanding environmental changes over the past and predict future environmental changes better in Anyang areas.The pollen analysis results of total of 122 surface soil show that the average arboreal pollen percentages are 18%,where Pinus and Ulmus are dominant pollen assemblages;and the shrubby pollen percentages below 3%,with Rhamnaceae as the dominant pollen types; herbaceous pollen percentages added up to73%,with Poaceae,Artemisia,Chenopodiaceae and Cruciferae as the major pollen types;Selaginella sinensis are the mainly fem spores with percentages less than 1%..In main pollen types,Pinus and Poaceae are mainly distributed in the eastern part of Anyang City,Artemisia is mainly located in the west of the city, Chenopodiaceae mainly appeared in the urban areas and near the its major roads,Cruciferous is mainly distributed in urban areas and in the northwest part of city,Humulus and Urtica usually appeared in the waste land.The pollen assemblages of different vegetation types such as vegetable land,farmland,woodland,wasteland,rapeseed land have different characters, and they can generally be sorted by PCoA.In the farmland and vegetable land,Poaceae has a high percentages with an average of 27%,and lower Artemisia percentages with average of 8%;In the wasteland and woodland,the arboreal pollen percentages are highest with average of 19%in all the vegetable types,where Pinus and Ulmus are dominant pollen types; Cruciferae has the highest pollen percentages(70%),and arboreal has the lowest pollen percentages in the rapeseed land.The pollen analysis of total of 29 paleo-soil samples which came from the below layer of Yinshang sites show that:the average arboreal pollen percentages are 42%,with Pinus as main pollen type;Shrubby pollen percentages below 2%;The average herbaceous pollen percentages add up to 46%,where Poaceae,Artemisia,Chenopodiaceae,Compositae and Ranunculaceae are dominant pollen types;Selaginella sinensis is the mainly fern spores.Higher arboreal pollen percentages(higher than 30%) and the appearrence of evergreen Quercus,indicate a warm and wet climate with forest or forest-steppe as the major vegetation type before the occurrence of Yinshang Culture.In the main pollen types, Pinus has a high percentage in the Anyang urban and its surrounding,evergreen Qurcus is mainly distributed in northern and southwest of Anyang,Poaceae is mainly located in the surrounding regions of Anyang City,Artemisia is mainly distributed in the western region and part of eastern region of Anyang,Chenopodiaceae is mainly distributed in southeastern and northwest of Anyang.In some paleosoil samples,the Poaceae pollen percentages are higher or near 20%which is very similar with the modern farmland,indicating the exist of farmland before the appearance of Yinshang Culture..The pollen assemblages contrast between the surface samples and paleo-soil samples indicate:with the fly of time,trees in Anyang area gradually reduced because of high arboreal pollen percentages in the paleosoil;and farmland in the eastern region gradually increased with the increase of proportion of Poaceae pollen the decrease of Arternisia pollen percentages. In western region of Anyang,for the higher altitude and near to the Taihang Mountains, Artemisia pollen percentages are higher both in the surface and in the paleosoil samples.