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通过对长江三角洲锦溪地区白莲湖附近人工剖面的孢粉研究,重建该地区7 230cal a BP前后的植被和气候。孢粉植物群反映当时气候略有波动,但整体上与全新世气候适宜期的温暖环境相一致。孢粉自下而上可以细分为4个组合带:Zone 1青冈栎含量丰富,反映温暖气候;Zone 2落叶栎有所增多,气候稍有转凉;Zone 3青冈栎含量再度增高,气候变暖;Zone 4松属和落叶栎明显增多,气候再度转凉。从沟鞭藻和相关孢粉类型的分布分析,除底部12号样品因孢粉含量低而未予考虑外,其它样品都指示沉积时期当地受到海水的影响。其中Zone 1和Zone 2孢粉植物群指示两次海水的进退过程。当前孢粉研究结果很好地反映出长江三角洲地区全新世大暖期的气候变化特征,以及与当时海平面变化的关联。
The vegetation and climate of 7 230 cal a BP in the area were reconstructed through the sporopollen research on the artificial section near Bailian Lake in Jinxi of the Yangtze River Delta. The pollen flora reflects a slight fluctuation of climate at that time, but it is generally in accordance with the warm environment of the Holocene climatic suitable period. The pollen grains could be subdivided into four bands from bottom to top: Zone 1 is rich in Cyclobalanopsis glauca, which reflects the warm climate; Quercus variabilis in Zone 2 is increased and the climate is slightly cooler; the content of Cyclobalanopsis glauca in Zone 3 is increased again, Warm; Zone 4 pine and deciduous oak increased significantly, the climate turns cooler again. From the distribution of dinoflagellates and related types of sporopollen, except for the bottom 12 samples, which were not considered due to the low sporopollen content, other samples indicated that the sediment was affected by seawater locally. Zone 1 and Zone 2 pollen flora indicate the course of the two seawater. The current pollen research results reflect the climatic characteristics of the Holocene Megathermal in the Yangtze River Delta and their correlation with the sea level changes at that time.