| A little research on ancient lakes on the south coastal plain of Laizhou Bay has been done, except briefly elaborating the development of ancient lakes in historical period from the perspective of historical geography, by looking up the historical document data. Because ancient lakes on the south coastal plain of Laizhou Bay lie in transitional area between sea and land, they receive the influence of sea level changes, river diversion, diastrophism and the activities of human beings, so the course of formation and change of ancient lakes are very complicated. Formation and change of ancient lakes are the results from the interaction of atmosphere, hydrosphere, biosphere, lithosphere and the activities of human beings. So by the study on formation and change of ancient lakes, general picture of environmental evolvement in the studied area can be revealed.The thesis concentrates on Judian Lakeingshuibo Lake sedimentary area which lies in the northern west of Shouguang City. By field investigation, the scope of Judian Lake?Qingshuibo Lake is fixed. Many bore holes in Shuangwangcheng Reservoir which lies in the sedimentary area are drilled and lots of terra drill data are collected. Five typical sections, i.e. section I ?I ,II 桰I,III桰II, IV桰V'and V ?V are drawn. The vertical sedimentary sequence of this sedimentary area is divided cbmbining the granularity features of sediments. By comparing with the strata of "Holocene Series of the coastal plain of Laizhou Bay" and combining 14C age measurement, the strata position and features of the lagoon梥hallow sea梑each sedimentary facies are confirmed. The stratigraphic division of upper marine facies of Holocene is done and the sedimentary environment of every stratum is affirmed. By spore-pollen analysis of 10 samples and combining the features of spore-pollen assemblage and climatic environment, the features of evolvement of climatic environment of this sedimentary area since the Middle Holocene are obtained. At the same time, by gathering a lot of historic document data, the historical evolvement of ancient lakes such as Judian Lake桻ingshuibo Lake, Heizhongbo Lake and Biehua Lake and the reasons of vanishment of lakes are discussed. By consulting the course of the evolvement of ancient lakes in Hebei Plain, the law of the evolvement of ancient lakes in the south coastal plain of Laizhou Bay is summed up. Based on the above analysis, the other factors reflecting the features of environmental evolvement and the spore-pollen assemblage of Huabei Plain, the features of environmental evolvement in the south coastal plain of Laizhou Bay since the Middle Holocene is summarized. Specific contents include the following:1. Introduction.The significance and purpose of choosing this subject, and achievement home and abroad in this field are introduced.2. Sketchy circumstances in the studied area.The scope of the studied area is defined, quaternary geomorphic and geologic condition is introduced, and the achievement of predecessors' studies on ancient lakes and environmental evolvement on the south coastal of Laizhou Bay is summed up.3. The acquirement of environmental information of sediments ------ take Judian lake桻ingshuibo lake as an example.Firstly, the lithologic features of bore holes in Judian lake ?Qingshuibo lake sedimentary area is analyzed, and five typical sections are drawn. Secondly, granularity analysis of sediments of upper marine facies of Holocene is done. Thirdly, by comparing with Holocene strata of the coastal plain of Shandong Peninsula, sedimentary strata of this area are divided into four layers, and sedimentary environments are comfirmed. Finally, through analyzing spore-pollen of 10 samples and consulting the research achievement of the subject, "Ancient Geographic Environmental Evolvement on the Coastal Plain of Laizhou Bay since Holocene", the features of climatic and environmental changes of this area since the Middle Holocene are gained.4. Formation and evolvement of ancient lakes.Firstly, the environmenta...
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