杭嘉湖平原全新世沉积的孢粉组合及其意义

本文通过对杭嘉湖平原六个钻孔的全新世沉积的孢粉分析,揭示了本区全新世沉积的六个孢粉组合,它们自下而上分别为:(1)松属、栎属、禾本科孢粉组合;(2)栎属、松属、禾本科孢粉组合;(3)青刚栎属、栲属、栎属、藜科孢粉组合;(4)松属、栎属、禾本科、藜科孢粉组合;(5)栎属、青刚栎属、栲属,禾本科孢粉组合(6)栎属、禾本科、水龙骨科孢粉组合。这六个孢粉组合反映了本地区全新世时期存在着六个古植被演变阶段和相应的六次气候波动,为本地区全新世地层划分提供了重要依据。     

杭州湾北部沿岸全新世的孢粉组合与地层、古地理探讨

杭州湾北部沿岸全新世的孢粉组合可划分成四个综合孢粉带,它们代表四个不同的气候与植被演变阶段,据此可将全新世划为早、中、晚三期,全新统相应地分成下、中、上三层。     

内蒙古赤峰盆地早白垩世地层和孢粉化石群

赤峰盆地是一个晚侏罗世晚期发展起来的陆相断陷盆地,主成盆期为早白垩世。盆地内沉积盖层包括了上侏罗统兴安岭群、下白垩统义县组、九佛堂组、沙海组、阜新组,以及孙家湾组。作者首次比较完整地介绍了赤峰盆地早白垩世岩石地层层序及孢粉化石组合序列,并对各地层单元的区域对比关系和地质时代归属进行了简要讨论。     

典型石漠化区不同植被表土孢粉组合的生态指示意义

通过对南平4个不同植被类型的表土样品的孢粉分析,得出了该区的表土孢粉组合特征.结果显示:研究区内的表土孢粉组合中草本植物占据优势,乔木主要为马尾松,灌木的种类和数量都很少,显示该区植被退化严重,表现出石漠化地区孢粉组合的显著特点.研究区内不同植被类型的表土孢粉组合差别明显,但与其相应的实际植被情况大致相同,能够较好地反映出石漠化地区现代植被的基本状况.表土孢粉组合中有很多喜钙性、旱生性、石生性植物,对生态恢复和重建有很好的指示意义,为该区恢复和重建自然生态环境提供参考性依据.     

Spore-pollen-climate factor transfer function and paleoenvironment reconstruction in Dajiuhu, Shennongjia,Central China

The identified results of 121 surface sediment spore-pollen samples in Shennongjia and meteorological data base of 30 years(January,1971―December,2000)of 7 meteorological stations around Dajiuhu, Shennongjia are used in this study.Selecting 55 species of common spore-pollen with the method of space fitting and stepwise regression we construct the pollen climate factor transfer function of annual mean tem- perature:T=7.649-2.33097X Abies -0.10873X Betula -0.17352X Compositae -0.13176X Cruciferae +0.13356XEuphorbiaceae -0.83069X Campanulaceae +1.96494XPyrrosia+0.38411XPteris+2.77741XSelaginella+0.04439XMonolites.We had reconstructed annual mean temperature series by use of the sporo-pollen samples concentra-tion percentage in peat section with 297 cm thickness in Dajiuhu since 15.753 kaBP.The temperature series reflect well the character of climatic change since the late glacial,which indicates extreme cold climate event of the Oldest Dryas,the Older Dryas,the Younger Dryas and the 8.2 kaBP,the same to the climate fluctuations of Bolling Warm Period and Allerod Warm Period,and the character of temperature change fluctuating frequently at the transition age from the late glacial to the Holocene.The reconstructed temperature also indicate Holocene Optimum,late Holocene warm-dry climate,and the character of climatic change in Dajiuhu in the last 1 ka.The conclusion is that the sporo-pollen samples have important climatic significance to surface sediment and the section of Dajiuhu,Shennongjia and important reference value to studying climatic change during the last glaciation by the temperature transfer function and reconstructed temperature series.     

杭嘉湖平原全新世沉积的孢粉组合及其意义

本文通过对杭嘉湖平原六个钻孔的全新世沉积的孢粉分析,揭示了本区全新世沉积的六个孢粉组合,它们自下而上分别为:(1)松属、栎属、禾本科孢粉组合;(2)栎属、松属、禾本科孢粉组合;(3)青刚栎属、栲属、栎属、藜科孢粉组合;(4)松属、栎属、禾本科、藜科孢粉组合;(5)栎属、青刚栎属、栲属,禾本科孢粉组合(6)栎属、禾本科、水龙骨科孢粉组合.这六个孢粉组合反映了本地区全新世时期存在着六个古植被演变阶段和相应的六次气候波动,为本地区全新世地层划分提供了重要依据.