Spore-Pollen Analysis And Research On Charcoal Plant Remains Of Changshan Site In 2016

The Changshan site is a very important site in the middle reach area of the Dongliao River.It is well preserved and had been used for a long time from the Neolithic Age to modern times.By systematic archaeological excavation,lots of remains and relics were found.In this paper,the methods of archaeobotany were used.Using the spore-pollen soil samples collected at the Changshan site and the charring particles of palnts collected by systematic flotation sampling with laboratory analysis,abundant information about spore-pollen and carbonized plant remains were obtained.Through the analysis of the collected spore-pollen and carbonized plant remains,we have a preliminary understanding and knowledge about the climate and vegetation,environmental evolution,the level of agricultural development,and plant utilization during the period of the occupation of Changshan site.The spore-pollen soil samples were gathered from the field and identified in the laboratory.Except sample No.2 and No.3,a large number of spores and pollen were found in the other samples,including Asteraceae,Pseudostellaria,Polygonaceae,Polygonaceae,Moraceae,Pine and so on.According to the habitat information reflected by each species,it is found that the environmental changes during the occupation of the Changshan site are very similar to those of the entire Northeast China.During the late Neolithic period,the climate was cold and dry,and the vegetation was mainly grassland;the climate in the early Bronze Age was warm and humid,and the vegetation was mainly grassland.The medium-term climate was improved,tending to warm and humid the woody plants also increased.But the climate gradually deteriorated to dry and cold in the later period with the reduction of vegetation,and the reduction of woody plants was more obvious.The climate in Liao and Jin Dynasties was relatively cool and humid,and the vegetation was mainly sparse forest steppe.The modern climate is cool and humid,and the vegetation was sparse forest steppe.In addition to some charring wood chips,a lot of carbonized plant seeds were found by flotation,of which there were crop seeds including Setaria italica and Panicum miliaceum,and weed seeds including Setaria,Digitaria,Chenopodium,Polygonaceae,Amaranthaceae,Cyperaceae,etc.The charring plant seeds were all herbaceous plants,and the woody plants were not found obviously.After statistical analysis,it was found that the seeds of millet,broomcorn millet and foxtail accounted for the vast majority of charring plant seeds,which were significantly more than other species.Among them,the quantity of seeds of Setaria viridis is large,but the ratio of the quantity of those seeds to the quantity of millet or broomcorn millet was gradually decreasing.It revealed that the economic pattern in the Changshan site had always been dry farming in north China.The agricultural production mode was relatively extensive,although it gradually becomes precision agriculture,but on the whole,it was still quite extensive with the existence of many weeds.Through the analysis of other plant seeds,it was found that,in addition to acquiring plant-based foods,the Changshan site also utilized forexploiting of plant resources in the wild,including collecting edible potherbs,such as alfalfa and crabgrass etc.,and using wild plants as forages for raising livestock.It was also likely that there would be the utilization of plants as medicine,but this was still uncertain.Systematic archaeobotanical studies were carried out at the Changshan site,including researching the spore-pollen and charring plant remains,provide environmental information for a comprehensive archaeological analysis of the site.At the same time,the research is the first case for studying the middle reaches of the Dongliao River using archaeobotanical methods,which provided abundant information for studying the evolution of climatic environment,agricultural development and plant utilization in the region.