根据野外调查和室内鉴定、分析了黄土高原350~280 ka PB前后的气候迁移变化问题。资料表明,在地处黄土高原南缘的陕西长安少陵塬第3层古土壤形成中晚期和第4层古土壤形成的早期有代表荒漠草原环境的石膏发育,指示当时黄土高原气候发生...根据野外调查和室内鉴定、分析了黄土高原350~280 ka PB前后的气候迁移变化问题。资料表明,在地处黄土高原南缘的陕西长安少陵塬第3层古土壤形成中晚期和第4层古土壤形成的早期有代表荒漠草原环境的石膏发育,指示当时黄土高原气候发生了显著的干旱化与大幅度的荒漠草原南迁,与现在这个地区气候相比,气候带向南迁移了约4个纬度,也说明在这段时间内荒漠草原广布于黄土高原。石膏的发育还揭示,在350~280 ka PB前后黄土高原气候发生了性质的转变,第3层古土壤发育中晚期和第4层古土壤发育早期最少各有一个时期气候特别冷干,当时该区已基本不受夏季风的影响,并处于冬季风气候控制的环境下。展开更多
野外调查和室内分析资料表明,黄土高原中部的洛川一带500ka前后发育的第5层古土壤上、下部分层的CaCO3淀积层和部分Fe2O3已迁出了古土壤层,该层古土壤是不具CaCO3淀积层的淋溶性中酸性土壤,剖面构型为Bts Cs Cl Bk C型。这一古土壤底部...野外调查和室内分析资料表明,黄土高原中部的洛川一带500ka前后发育的第5层古土壤上、下部分层的CaCO3淀积层和部分Fe2O3已迁出了古土壤层,该层古土壤是不具CaCO3淀积层的淋溶性中酸性土壤,剖面构型为Bts Cs Cl Bk C型。这一古土壤底部之下发育了风化淋滤黄土层,指示当时风化淋滤深度和强度比现今大,是250万年来最温湿气候事件的显示。该层古土壤发育时亚热带气候迁移到了黄土高原中部,当时年均温度为15℃左右,年均降水量为850mm左右。展开更多
Daily temperature data from 599 stations across China for the years 1961 to 2007 were used to analyze the changes in the natural regional boundaries. The results show that the accumulated temperature ≥10℃ and its du...Daily temperature data from 599 stations across China for the years 1961 to 2007 were used to analyze the changes in the natural regional boundaries. The results show that the accumulated temperature ≥10℃ and its duration changed dramatically from the end of 1990s to the early 21 st century. The amplitude of natural regional boundaries was greater in the 21st century than it was in the 20th century. In the eastern region of China, the climatic zones were migrating generally northward, with the northern edge of the subtropical zone and the eastern section of the warm temperate zone showing an obvious northward shift of up to 1-3° of latitude. The climatic zones moved south in the Qinghal-Tibet Plateau, western Inner Mongolia, and some areas of western Xinjiang, and slightly to the north in other parts of the western region.展开更多
文摘根据野外调查和室内鉴定、分析了黄土高原350~280 ka PB前后的气候迁移变化问题。资料表明,在地处黄土高原南缘的陕西长安少陵塬第3层古土壤形成中晚期和第4层古土壤形成的早期有代表荒漠草原环境的石膏发育,指示当时黄土高原气候发生了显著的干旱化与大幅度的荒漠草原南迁,与现在这个地区气候相比,气候带向南迁移了约4个纬度,也说明在这段时间内荒漠草原广布于黄土高原。石膏的发育还揭示,在350~280 ka PB前后黄土高原气候发生了性质的转变,第3层古土壤发育中晚期和第4层古土壤发育早期最少各有一个时期气候特别冷干,当时该区已基本不受夏季风的影响,并处于冬季风气候控制的环境下。
文摘野外调查和室内分析资料表明,黄土高原中部的洛川一带500ka前后发育的第5层古土壤上、下部分层的CaCO3淀积层和部分Fe2O3已迁出了古土壤层,该层古土壤是不具CaCO3淀积层的淋溶性中酸性土壤,剖面构型为Bts Cs Cl Bk C型。这一古土壤底部之下发育了风化淋滤黄土层,指示当时风化淋滤深度和强度比现今大,是250万年来最温湿气候事件的显示。该层古土壤发育时亚热带气候迁移到了黄土高原中部,当时年均温度为15℃左右,年均降水量为850mm左右。
基金supported by the National Natural Science Foundation of China (Grant No.40875053)
文摘Daily temperature data from 599 stations across China for the years 1961 to 2007 were used to analyze the changes in the natural regional boundaries. The results show that the accumulated temperature ≥10℃ and its duration changed dramatically from the end of 1990s to the early 21 st century. The amplitude of natural regional boundaries was greater in the 21st century than it was in the 20th century. In the eastern region of China, the climatic zones were migrating generally northward, with the northern edge of the subtropical zone and the eastern section of the warm temperate zone showing an obvious northward shift of up to 1-3° of latitude. The climatic zones moved south in the Qinghal-Tibet Plateau, western Inner Mongolia, and some areas of western Xinjiang, and slightly to the north in other parts of the western region.