摘要:
本文在对北京东甘池东剖面进行孢粉分析、炭屑统计、烧失量测定等的基础上,通过与北京东甘池西剖面、坟庄剖面、高里掌剖面的孢粉谱等对比,讨论了北京地区不同沉积环境和地貌单元中沉积物沉积和孢粉沉积的差别,进一步分析了东甘池东剖面、西剖面整个时期孢粉浓度偏低,特别是7000aB.P.以后孢粉浓度、炭屑统计、烧失量产生低值的原因。为科学地利用孢粉资料和其他古气候记录资料恢复过去植被和气候提供了一定的依据。
Abstract:
In this paper, 197 samples were gathered from a 820cm profile at Dongganchi of Fangshan in Beijing, and the pollen assem-blages, charcoal, loss-on-ignition were obtained, Based on the investigations of pollen assemblages, charcoal, and loss-on-ignitionand comparison with the pollen assemblages of west profile at Dongganchi, Fenzhang profile and Gaoiizhang profile, the differenceslandform units and in different sedimentary environments pollen deposits were discussed. For example, the east and west profiles ofDongganchi are located between two proluvial fans, Fenzhang profile of Fanshan is located in the front of marginal depressions ofproluvial fan, and Gaolizhang profile is located in, alluvial plain. So the primary reason of the decrease of pollen-spore concentration,charcoal and loss-on-ignitions in east and west profiles of Dongganchi since 7000a B. P. was given. An important information couldbe provided for further studies of paleovegetation and paleoclimate research by this.