| Global climate change and the resulting sea-level change is a hot research issue of the world today. The zone near by the coast is the interaction region with atmosphere lithosphere hydrosphere and biosphere,which is sensitive to climate change and sea level, at the same time it is also a high density and economically quickly-developed area of human. Therefore, to carry out research on the shoreline change and vegetation change related to the survival and development of human and other animals. Because of various hydrodynamic effects and siltation role make the growth of planted community near by the coast show a successional sequence change.If this regular distribution characteristics are associated with the position of the coastline and other environmental features, providing a theoretical idea for us to open investigation.Reconstruction in palynological assemblages-vegetation-climate relationship by Palynology principle has been very mature, especially in the field of oceanography with the continuous application of new technologies on Micropaleontology and high-precision and high-resolution dating method makes use of the principle of palynology quantitative paleoclimate research flourish.Many scholars have studied vegetation condition and surface pollen combination by means of Pollen analysis in arid and semi-arid areas found out that the Chenopodiaceae pollen existed with high contents in this region. Along the coastline due to the tide cyclical fluctuation and the feature of strong surface evaporation, making this region a high saline land. Through field investigation we found that the massive growth of the Chenopodiaceae vegetation along muddy shoreline, and the grouth of various vegetations are parallel to the shoreline from sea to land in order.To this end,this article by choosing two muddy coastl profile as research area. One is Red crowned crane wetland nature reserve in Yanchen city,Jiangsu province,anther one is Red Beach wetland nature reserve in Panjin cite,Liaonin province.By survey and topsoil acquisition, explore the quantitative relations between the Chenopodiaceae pollen contents and shoreline position based on pollen analysis of topsoil, thereby establish proxies for judgmenting medieval strata shoreline position can come true. Combined with previous use of the palynological assemblages on ancient sea-level change base on climatic fluctuation,to verify that conclusions credibility and practicality.According to pollen analysis of the two study areas and after the correction of the data result,it can be conclude that:1.In the muddy coast, after tides and seawater long time effection the land surfacesoil from the sea to the land, The vegetation strip take on the regulation that changed from the Suaeda communities to reed and than to farmland into the law of succession parallel to the shoreline in turn.Among that, Chenopodiaceae Suaeda growth close proximity to the shoreline.2.The chenopodiaceae pollen have the indicated significance to the shoreline location. When the Chenopodiaceae pollen content in the the muddy coast region topsoil more than60%or it Concentration values more than80,000eggs/g, we can determine that the region is nearby the coastline average of high tide.3.Though the ratio between the Chenopodiaceae pollen and Artemisia pollen or the Chenopodiaceae pollen and Gramineae pollen we can also judge the the location of the muddy coast. It can be represented that when the pollen ratio Artemisia/Chenopodiaceae reach0-5%,with an average of1.3%or when the pollen ratio Gramineae/Chenopodiaceae reach0-0.02can determine the location of the shoreline near the high tide level. |
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