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1.
基于中国北东样带东部森林区8个植被样方和表土花粉资料,定量分析了每种植物与表土花粉类型的关系。结果表明:花粉类型与植物关系密切,在α=0.05的显性水平上,相关系数(correlation coefficient)C值大都在0.5以上;表土花粉组合与植物群落间有较大的相似性,相似系数(CC)大于50%。采用定量描述花粉与植物关系的参数:联合指数(association index)A、超代表性指  相似文献   

2.
西藏两个小湖高分辨率的花粉记录   总被引:10,自引:0,他引:10  
西藏东南部封闭湖泊高分辨率的花粉记录反映,在16 ka BP以前花粉组合以藜科(Chenopodiaceae) 和蒿属(Artemisia) 为主,花粉浓度很低,应为荒漠草原植被。当时气候寒冷干燥,1 、7 月份和年均温分别低于现在当地7 ~10 ℃,0.5~1.5 ℃和4~6 ℃。年降水量仅250 mm 是现今当地年降水量的40 % ;12 ka BP以后气温和降水逐渐增加,出现木本植物花粉,桦属( Betula) 和松属( Pinus)等,在9 .2~5 ka BP发育森林或森林草甸;8~6 ka BP是研究区气候最适宜期,1、7 月份气温均高于现在2~3 ℃,年降水量比现在当地高100 mm 左右;5.5 ka BP以后气温和降水呈非线性下降,主要发育草原植被,直至现在  相似文献   

3.
塔里木盆地北缘侏罗纪孢粉组合   总被引:17,自引:6,他引:11  
本文系统地研究了塔里木盆地北缘侏罗纪的孢子花粉。共发现孢粉化石52属90种,以及藻类化石2属2种。建立侏罗纪的孢粉组合序列如下:(1)Disacciatrileti-Cyathidites组合(早侏罗世早期阿合组),(2)Cyathidites-Cibotiumspora-Disacciatrileti组合(早侏罗世晚期阳霞组),(3)Cyathidites-Neoraistrickia-Disacciatrileti组合(中侏罗世早期克孜勒努尔组),(4)Cyathidites-Clasopolis组合(中侏罗世晚期恰克马克组)。根据孢粉组合特征讨论了地质时代,同时探讨了古植被和古气候的意义。  相似文献   

4.
本文对新疆吐鲁番-哈密盆地3口石油探井中黄山街组,郝家沟组共108块样品进行了孢粉分析研究。自下而上建立了晚三叠世两个孢粉组合,即Aratrisporites-Alisporites组合和Osmundacidites-Chordasporites组合,讨论了组合特征及其时代,并与国内外有关层位及化石群进行了分析比较;探讨了孢粉植物群所反映的古植被和古气候。  相似文献   

5.
沙漠/黄土过渡带13 Ka BP以来季风演化的古植被记录   总被引:15,自引:0,他引:15  
利用花粉分析结果并结合有机碳δ^13C及高精度^14C测年等资料,阐明沙漠/黄土过渡区13ka BP以来古植被记录的季风气候事件。古植被经历了荒漠草原-干草原-半荒漠-湿润草原-荒漠-疏林草原-荒漠草原-草原-荒漠草原9个阶段。冰后期的半荒漠-湿润草原-荒漠对应于其中冷干-凉湿-冷干的Younger Dryas事件,全新世气候适宜期以及4.5-3.5ka BP的另一气候料适宜期等在研究区均有明显表  相似文献   

6.
近年来中国二叠纪古植物学研究简述刘照华李承森耿宝印(中国科学院植物研究所,北京100093)ADVANCESOFPALAEOBOTANICALRESEARCHESOFPERMIANINCHINALiuZhao-huaLiCheng-senGengB...  相似文献   

7.
通过四川螺髻山(1984、2017年)表土和化石孢粉与植被的关系分析发现:孢粉组合中木本植物含量(91.0%)占绝对优势,松属、冷杉属、青冈属、常绿栎类、落叶栎类、桤木属、杜鹃花科、禾本科和蒿属为主要花粉类型;人工次生林花粉组合能很好地反映母体植被的群落特征,并可指示优势种的存在和人类活动痕迹;针阔混交林花粉组合能较好地反映群落整体特征,花粉类型能与母体植被中优势种较好地对应;常绿阔叶林、针叶林和灌丛草甸的花粉组合难以反映母体植被的群落特征。DCA表明,花粉谱的百分含量,能较好地区分人工扰动植被和天然植被,但人工次生林、常绿阔叶林和针阔混交林之间以及针叶林和灌丛草甸之间未能区分。30年前后表土孢粉组合变化明显,1984年样品以松属、青冈属和桤木属等花粉为主,而2017年采样分析中松属、桤木属花粉占绝对优势。随着人类活动的加强,部分地区松树和桤木大面积飞播或种植,表土孢粉组合对当地植被指示意义与扰动强度呈负相关关系。现生植被与表土孢粉组合的差异能为恢复古植被和古环境提供参考,但原生植被已经被破坏地区的孢粉图谱,就很难作为重建历史时期植被的根据。本研究可以为亚热带山地利用孢粉学恢复第四纪时期植被与气候,探讨人类活动与环境的关系提供理论依据和实践参考。  相似文献   

8.
刘炳仑 《化石》2008,(1):24-25
一般认为,埋藏在海、陆地层中的油、气资源等各种沉积矿藏的形成和分布,都与当时的古植被、古地理、古地貌和古气候有着十分密切的关系.而这一切的一切,又都与植物的孢子-花粉结下了不解之缘.  相似文献   

9.
本文对新疆吐鲁番-哈密盆地3口石油探井中黄山街组、郝家沟组共108块样品进行了孢粉分析研究。自下而上建立了晚三叠世两个孢粉组合,即Aratrisporites-Alisporites组合和Os-mundacidites-Chordasporites组合,讨论了组合特征及其时代,并与国内外有关层位及化石群进行了分析比较;探讨了孢粉植物群所反映的古植被和古气候。  相似文献   

10.
通过对青藏高原东北缘不同群落19个样点的表土花粉组合特征及其与植物群落之间关系的研究,发现:(1)针叶林和高山灌丛的花粉组合特征与植物群落有较好的对应关系,落叶阔叶林和针阔混交林的花粉组合基本上能反映植被群落特征,草本植物的花粉组合未能反映植物群落的数量特征;(2)主要花粉类型中松属、云杉属和桦属花粉具超代表性,杜鹃花科、杨属和柏科花粉具低代表性;(3)通过花粉相对含量降趋势对应分析(DCA)能较好地区分不同植被类型。该研究成果可为本地区及相似地区的古植被和古环境重建提供基础和验证资料。  相似文献   

11.
Qinghai Lake is the largest inland saline lake in China. it is situated in the northeastern part of the Qinghai Xizang Plateau. This paper is based on the information of the sporo-pollen assemblages of 47 samples from the drill core and surface samples. The general treads of vegetational and climatic changes since 11,000 years B. P. may be subdivided in ascending order as follows: In the first stage which corresponds to zone Ⅰ of the sporo-pollen assemlage, the vegetation during the past of 11,000–10,000 years was represented by a temperate shrub, semi-shrub and steppe, consisting of Chenopodiaceae. Artemisia, Nitraria, Ephedra and Gramineae were predominant. At the same time, some subalpine conifers, Pinus, Picea and Betula, would grow by the side of rivers and lakes, the climate was warmer and wetter than that of the Late Pleistocene. Due to the rising temperature in this zone, the Pleistocene-Holocene boundary might be estimated at about 11,000 years B. P.. The vegetation of the first stage belonges to temperate steppe with a few trees: In the second stage (ZoneⅡ of pollen), the vegetation was characterized by a temperate forest steppe during this period of 10,000 to 8,000 years B. P. Forest area apparently increased and some broadleaf deciduous and need leaf evergretn trees, such as Quercus, Betula, Pinus and Picea, grew by lakes and on mountains. At this time, the climate was warmer and wetter than that of the first stage. In the third stage (Zone Ⅲ) between B,000 and 3,500 years B. P, The vegetation was composed of a temperate mixed broad-leaf deciduous and needle-leaf evtrgreen forest. The needle-leaf evergreen forest consisting of Picea, Pinus, Abies, Betula grew in temperate zone mountains. The climate was relatively warm and wet. The fouth stage (zone IV), the vegetation was dominated by shrub semishrub, dwarf semishrubs, steppe and semi-arbors. Some trees consisting of Betula, Picea, and Pinus decreased in number in the lake regions. Some subalpine cold temperature evergreen trees, such as Abies and picea disappeared from the lake region. This indicated that the climate was warmer and drier during the past 3500–1500 years B. P. than the third zone. In the fifth stage (pollen zone V), the vegetation comprised steppe and desert from 1500 years ago to the present time. Some arborealtrus such as Betula and Pinus were less increased about 500 years B. P. at this time the temperate and wet slightly, rose up. From the above analysis, it is clear that the Qinghai lake region has been confronted with the vegetational and climatic changes since ll,000 years B. P. Therefore, the palynoflora of the Qinghai lake has its significance in Geography and vegetational history.  相似文献   

12.
大小兴安岭泥炭的孢粉记录及演变过程研究   总被引:4,自引:0,他引:4  
根据3个高位泥炭剖面孢粉分析,揭示大注兴安岭分别于5000aB.P.、2700aB。.P.以来孢粉组合特征和植物群与气候演变过程。小兴安岭北部山地森林疲宣传早分为2个时期,5000-3000aB.P.桦为主落叶阔叶林;3000aB.P.--现今为红松、云冷杉为主,混有少量桦寒温必殖阔叶混交林。气候由温凉偏干向冷偏湿方向发展大兴安岭北部山地,2700~1800aB.P.以来,已构成针叶林为主(樟子松  相似文献   

13.
In this paper, the division of the two pollen zones is discussed based on the results of pollen and spores analysis and 14C dating in the Daganba area, Zhijin County, central Guizhou Province. Zone Ⅰ represents a forest of mixed evergreen-deciduous broad-leaved trees closed subtropic mountain and dominated by Fagus, Quercus, Cyclobalanopsis, Carpinus and Castanea (Castanopsis, Lithocarpus) together with Pinus, Tsuga and Abies till 23000 yr B.P. It stands for the Dali interstadial climate, cool and moist. Zone Ⅱ vegetation adopted dry climate. During the time from 23000 yr B. P. to the fullglacial period the forest cowered and the fern extended. The pioneer trees such as Pinus, Betula began to grow towards the end of the dry phase. The genus Fagus is of great importance in studing ecology and geography of the flora. The retirement and growth of Fagus forest reveals the paleoenvironment changes.  相似文献   

14.
11000年以来太湖地区的植被与气候变化   总被引:12,自引:0,他引:12  
根据太湖盆地3个钻孔、约自11000年以来的孢粉分析结果将其划分为3个阶段:1)11000—9000aB.P,该段虽以Pinus为主的针叶植物占有一定的优势,但起主导作用的仍以壳斗科为主的阔叶乔木种类,尤其是其间尚含有不少的亚热带成分,推测当时该区地带性植被已为亚热带落叶常绿阔叶林,鉴于植被中尚含有少量耐寒的Abies和Picea,推测当时气温可能较今略低;2)9000—5000(5400)aB.P,该段为常绿阔叶林大发展时期,气候温暖适宜,为全新世最佳期,气温约较今高1—2C;3)5000?aB.P.-现在,孢粉组合特征显示,阔叶木本植物就总的来说呈下降趋势,尤其是亚热带成分,与其相反,针叶和一些暖温带成分的含量则略有上升,表明该段气温较前一阶段有所下降,但该阶段的植被受人类活动的影响较大。  相似文献   

15.
根据长江三角洲地区全新世9个具代表性钻孔的孢粉分析结果讨论了本区约自12000年以来的环境变迁。孢粉序列表明:本区约在距今12000年前就已发育了亚热带性质的落叶常绿阔叶林,约在9000—5000aB.P.常绿阔叶林获得大发展。孢粉序列良好地记录了古季风盛衰的历史,表现在:12000—10800aB.P.较温湿,东南季风强度加强;10800(或11000-10000(或10300)aB.P.偏闵干,东南季风强度减弱,对应于新仙女木期;约自10000a.P.起,气候好转,气温明显上升,东南季风强度再次增强,约在9000—5000aB.P.温暖湿润,为东南季风强盛期。此外.还讨论了约在距今11000年前的海侵,全新世下限和哥德堡事件的年代问题,并确定哥德堡事件的年限为11000—1000aB。P。  相似文献   

16.
In the previous paper authors found the vegetational and climatic changes in the past 30,000–10,000 years in Beijing. This paper is based on the informations of the sporo-pollen assemblages obtained from the Gaolizang, Dawangzhang, Yinjiahe, Xiwu- tiyng etc. with drilling cores in the vicinity of Beijing. About 12,000–10,000 years ago deciduous broad-leaved trees were flourishing in Beijing. At that time the climate was warm and rather wet. 10,000–8,000 years ago, the herbaceous plants, such as Artemisia, Compositae were flourishing in plain of Beijing and mountainous region was dominant in subalpine conifer forest, consisting of Pinus, Picea and Abies, According to the needle-leaved forest increasing at that time we think about 9,000 B. P. that climate was cool and wetter. In the past 8,000–6,000 years, needle-leaved and deciduous broad-leaved mixed forest, consisting of Pinus, Quercus and Betula thrived under a warm and wetter climate, the bogs were better developed in plain. During 6,000–2,000 years, in general review on the sporopollen assemblages of the Beijing we think that the climate was warm, especial about 5,000 years ago, the flora was mainly composed of deciduous broad-leaved trees, such as Ulmus, Quercus, Morus and Betula. But during 5,600 years ago or so, spruce-fir forest became predominant in the low land and the plain of Beijing again. At that time the annual mean temperature was lower than that of the present. It was corresponed to new glacial period. The flora mainly composed of Pinus was obviously reduced since 2,000 years. The glassland even increased in Beijing.  相似文献   

17.
Late Quaternary vegetation and climatic history of eastern Nepal   总被引:1,自引:0,他引:1  
The late Quaternary vegetation and climatic history at high altitude in eastern Nepal was studied through stratigraphy, radiocarbon dating and pollen analysis. The Thulo Pokhari lake (27°41′ N, 87°43′ E, ca. 3980 m a.s.l.) is just above the subalpine Abies spectabilis–Betula utilis forest zone and surrounded by Rhododendron scrub. The climate in the studied area is very humid under the influence of the monsoon. Silty sediments suggesting lake conditions prevailed at the lower part of the sediment samples, whereas the upper part consisted mainly of herbaceous peat indicating a mire condition. The pollen record extends back to ca. 11000 yr bp . Although the absence of major changes between the pollen assemblages of the Pleistocene and those in the Holocene was attributed to the situation of the sampling plot above the forest limit, the results suggest the following history. (1) The abundance of Pinus pollen around 11000 yr bp represents expansion of the area unoccupied by late successional trees and/or a drier condition. Significant occurrence of Picea pollen is noteworthy, since this genus is absent in eastern Nepal at present in spite of its wide distribution throughout the neighbouring areas of the Himalayas. (2) The increase in abundance of Quercus pollen and the decline in Pinus pollen in the latest Pleistocene represent climatic amelioration favourable to late successional mesophytes. (3) The climate was most moist and mild in the SP-III, although the absolute age of the pollen zone is not distinct. The percentages of broadleaved trees such as Alnus, Betula, Carpinus and Corylus were increased at the expense of Quercus and coniferous pollen types. Sedimentation was interrupted by lake level decline and/or glacial advance during the period from ca. 11000–1600 yr bp . (4) The increase in abundance of coniferous pollen types such as Pinus, Abies and Tsuga indicates that the climate became drier and cooler, and the present subalpine forest zone composed of A. spectabilis, T. dumosa and Betula utilis was established around 1600 yr bp . The formation of bog or alpine meadow vegetation during the period was shown by the 14C dates of the peat and the increase in Rosaceae and herbaceous pollen. (5) The increase in abundance of Ericaceae and Alnus pollen in the SP-V indicates that the present alpine Rhododendron scrub zone has been established since ca. 940 yr bp as a result of human influence on the original vegetation. This interpretation is supported by the decline in the proportion of arboreal pollen. Since the age of the initiation of human influence varies with the altitude and region, further study will be necessary to determine the accurate age.  相似文献   

18.
潮汕平原近五万年来的孢粉植物群与古气候   总被引:6,自引:0,他引:6  
  相似文献   

19.
长江三角洲东缘晚新近纪沉积的孢粉与古环境研究   总被引:5,自引:1,他引:4  
作者对长江三角洲东缘地区的南汇鹤鸣孔(Hm)、东海1井、高桥G2孔3口钻井晚新近纪地层的孢粉作了研究和对比,划分出了6个孢粉组合带和3个亚带,恢复了本地区植被演替、气候波动的6个阶段:第1阶段为稀疏的针叶、落叶阔叶混交林,反映气候凉冷稍湿;第2阶段为针叶阔叶混交林草地,反映气候温凉略湿;第3阶段为含常绿阔叶树的针叶阔叶混交林,反映气候温和略干;第4阶段为以常绿栎类、栲属、杨梅等为主的常绿阔叶林,反映气候热暖潮湿;第5阶段是以栎、松、禾本科为主的针叶、阔叶混交林,反映气候温暖略干;第6阶段是以落叶栎类、常绿栎类、松为主的落叶阔叶、常绿阔叶、针叶混交林草地,反映气候温暖湿润。这种气候波动与世界性气候变化相一致,为本地区的地层年代划分和对比提供了新的证据,为晚新近纪古植被、古气候、古环境的重建提供了重要的孢粉学资料。  相似文献   

20.
Climate changes are assumed to shift the ranges of tree species and forest biomes. Such range shifts result from changes in abundances of tree species or functional types. Owing to global warming, the abundance of a tree species or functional type is expected to increase near the colder edge of its range and decrease near the warmer edge. This study examined directional changes in abundance and demographic parameters of forest trees along a temperature gradient, as well as a successional gradient, in Japan. Changes in the relative abundance of each of four functional types (evergreen broad‐leaved, deciduous broad‐leaved, evergreen temperate conifer, and evergreen boreal conifer) and the demography of each species (recruitment rate, mortality, and population growth rate) were analyzed in 39 permanent forest plots across the Japanese archipelago. Directional changes in the relative abundance of functional types were detected along the temperature gradient. Relative abundance of evergreen broad‐leaved trees increased near their colder range boundaries, especially in secondary forests, coinciding with the decrease in deciduous broad‐leaved trees. Similarly, relative abundance of deciduous broad‐leaved trees increased near their colder range boundaries, coinciding with the decrease in boreal conifers. These functional‐type‐level changes were mainly due to higher recruitment rates and partly to the lower mortality of individual species at colder sites. This is the first report to show that tree species abundances in temperate forests are changing directionally along a temperature gradient, which might be due to current or past climate changes as well as recovery from past disturbances.  相似文献   

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