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本文根据湖东北侧 4个钻孔的孢粉分析 ,1 4 C和古地磁测试 ,并结合钙质超微化石、介形类和有孔虫所确定的海侵地层 ,将太湖地区划为 10个孢粉带 ,再参照长江下游相关资料 ,着重对 12 .7— 1.5万年以来的 4个孢粉带作了较深入的环境探讨 ,揭示出 带 (12 .7— 7.0万年 )为常绿落叶阔叶混交林 ,反映温暖湿润的亚热带气候 ,其主要温暖阶段冬温较今高 4— 5°C,当时湿度相对偏大 ,当然其中也有凉湿与干凉时段。 带 (7.0— 3.0万年 )为疏林草原 ,反映冷 (半 )干气候 ,其主要寒冷阶段年均温为 8°C左右。但仍存在剧烈的气候波动。 带 (3.0— 2 .1万年 )为温性常绿落叶阔叶混交林 ,反映温凉湿润的季风海洋性气候 ,其主要温凉阶段生长季月均温比现在低约 3°C。其中亦有更为干冷或暖湿时期。 带 (2 .1— 1.5万年 )为森林草原 -草原或干草原植被 ,其极干冷阶段年均温约 8°C,年降雨量 40 0 m m左右
Based on the sporopollen analysis, 14C and paleomagnetic tests of 4 boreholes on the northeastern side of Lake Huanghuang and the transgression strata determined by calcareous nannofossils, ostracods and foraminifera, 10 sporopollen, and then refer to the relevant data of the lower reaches of the Yangtze River, focusing on the 12 127,000 to 15,000 years of four sporopollen made in-depth environmental studies reveal the band (12.7-7.0 million) as The evergreen and deciduous broad-leaved mixed forest reflects the warm and humid subtropical climate. The main warm winter temperature is 4-5 ° C higher than that of the present day. At that time, the humidity was relatively large, of course, there were also cool, wet and dry periods. Belt (7.0-3.0 million years) is a sparse grassland, reflecting the cold (semi) dry climate, the average annual temperature during the main cold phase is about 8 ° C. However, there are still severe climate fluctuations. The belt (3.0-2.1 million years) is a temperate evergreen and deciduous broad-leaved mixed forest reflecting the warm, wet and humid monsoon maritime climate with a mean monthly mean temperature of about 3 ° C lower than the current temperature during the main warm-cool phase. There are also more dry or warm wet period. Belts (2.1-1.5 million years) are forest steppe-steppe or steppe vegetation with an average annual temperature of about 8 ° C in very dry and cold periods and an annual rainfall of 40 0 m m