【摘要】 本文探讨了一万年来的全新世期间,白洋淀兴起、扩张和收缩的变迁过程,恢复了各个发展阶段的古湖淀范围,论述了相应时期的古环境特征,指出了白洋淀令后的演变趋势。更多还原

【Abstract】 The Baiyangdian Lake is situated in a depression between the alluvial fans of yongding River and Hutuo River at the eastern foot of the Taihang Moun-tains. It has long been known as "a bright pearl of the Central Hebei Plain". However, the bright pearl is recently in danger of being annihilated. For this reason it is very important studying its evolutional law since 10,000 years ago and forecasting its developmental trend in the future. According to a large amount of field observations , drill records and historical-archaeological materils, a lithofacies-paleogeographic sectional map of Baiyangdian Area in the Holocene was drawn. It shows that the Holocene Series may be divided into three phases. In the Lower Holocene Series there were mainly alluvial sediments, but limnetic deposits occupied an important place in the Middle Holocene Series and the greyish black oozy layer which represented the limnetic environment possessed greater thickness and wider extent. In the upper Holocene Series the alluvium predominated again and covered over the limnetic deposits of the Middle Holocene Series.Futhermore the auther indicated that the ancient Baiyangolian Lake had undergone three stages of evolution during the last 10,000 years. In the Early Holocene the previous lake which had been died out in the dry and cold weather at the end of the Late Pleistocene rejuvenated once again around the present lake. Owing to the Atlantic Climate Optimum and the transgression in the eastern part of the Hebei Plain, the extent of the ancient lake expanded to the maximum in the Middle Holocene. However, in the Late Holocene the vast ancient Baiyangdidn lake was disintegrated, contracted step by step and died out in greater part, and only the present Baiyangdian Lake survived.The main factors controlling the expansion and contraction of the lake are climatic changes and sea level fluctuations. In addition, both the deposition of the rivers and man’s irrational use of natural resources have accelerated the processes of disintegration and contraction of the lake in the Late Holocene.更多还原