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1.
燕山地区花粉散布特征研究   总被引:1,自引:0,他引:1  
燕山南部花粉散布特征研究表明 ,空气中的花粉反映的是植物花期的季节性变化 ;表土花粉是植物多年花粉散布的混合 ;冲积物花粉与空气中和表土花粉显著不同 ,是取样点上游表土花粉的混合 ,与取样点周围植被关系较小。因此 ,根据冲积物花粉恢复古植被 ,反映的是整个流域的植被面貌 ,而不是某一点的植被特征  相似文献   

2.
燕山地区花粉散布特征研究   总被引:8,自引:0,他引:8  
燕山南部花散布特征研究表明,空气中的花粉反映的植物花植的季节性变化。表土花粉是植物多年花粉散布的混合,冲积物花粉与空气中表土花粉显著不同,是取样点上游表土花粉的混合,与取样点周围植被关系较小,因此,根据冲积物花粉复古植被,反映的是整个地流域的植被面貌,而不是某一点的植被特征。  相似文献   

3.
西北干旱区石羊河流域表土花粉分析   总被引:4,自引:0,他引:4  
程波  陈发虎 《中国沙漠》2010,30(2):350-356
干旱区石羊河流域不同植被带55个表土样的花粉分析结果显示,本流域表土花粉组合可以分为两部分,第一部分是荒漠草原带以上的山地植被花粉组合,其特征是云杉花粉占绝对优势,除森林带以外,基本不反映当地植被;第二部分是荒漠带以下的表土花粉组合,主要以灌木和草本植物花粉占优势,基本能反映当地的植被状况。影响石羊河流域表土花粉组合的主要因素是风力。主要科属花粉的浓度与植被状况对应良好,峰值区基本都位于其母体植物占优势的植被带中,但花粉百分含量受研究区气候、植被分布等因素影响,与现代植被的对应关系稍差。大部分灌木和草本花粉的含量变化基本能反映植被,但乔木花粉含量不能正确反映森林分布状况。  相似文献   

4.
天山南坡表土孢粉分析及其与植被的数量关系   总被引:32,自引:4,他引:32  
本文通过对天山南坡各植被带的表土孢粉分析,研究了主要植物花粉的百分含量与其相应樾物盖度之间的数量关系,计算出不同植被带中主要植物的R值之比的比值。  相似文献   

5.
姚祖驹 《地理研究》1989,8(1):101-101
本文是对我国暖温带山地条件下,表土中花粉与植物关系的试验研究。文中通过百分比图谱和浓度图谱的分析,得出了中条山林区表土花粉谱基本上反映了植被的基本特征,而浓度图在反映植被特征要比百分图显著,得出了几种主要树种的花粉百分含量的代表性顺序。对花粉散布规律进行了讨论,认为影响花粉散布的决定性的因素是气流运动和花粉源。本文还提出了在孢粉工作中,野外工作,实验室分析、鉴定、资料处理等过程严格系统化、规范化具有重要意义。  相似文献   

6.
贺兰山西坡4个植被类型(荒漠草原、榆树疏林、青海云杉林、高山灌丛草甸)的18个表土样品和12个捕捉器样品花粉组合与周围植被对比研究表明,表土和捕捉器样品花粉组合能较好地代表当地的植被类型,但荒漠草原带、榆树疏林带和高山灌丛草甸带捕捉器样品花粉组合表现植物建群种比表土样品好,青海云杉林植被带表土样品花粉组合表现植物建群种比捕捉器样品好。松属、蒿属和藜科花粉表土样品花粉组合百分比高于捕捉器样品,表明这4种花粉类型易于在表土环境保存,蔷薇科、豆科和杨属捕捉器样品花粉组合百分比高于表土样品,表明这3种花粉类型不易在表土环境保存。捕捉器样品花粉组合反映植物多样性比表土样品好,绣线菊、百合科、毛茛科和石竹科花粉在捕捉器样品花粉组合出现,而在表土样品花粉组合均未发现。捕捉器样品花粉组合聚类分析结果显示不同植被带花粉组合差异明显,而表土样品花粉组合聚类分析只可区分荒漠草原植被和高山灌丛草甸植被。  相似文献   

7.
选取南洛河上游洛南盆地10 种植被类型下40 处样点表土苔藓开展孢粉与植被关系的研究.结果表明,表土中孢粉组成能很好地反映植被类型.森林表土中乔木植物花粉含量平均值大于40%,且有较高含量的中华卷柏孢子;疏林草原、灌丛群落中乔木植物花粉平均含量分别为13.2%和16.6%,灌木植物花粉相对草丛群落含量较高;草丛群落和农田中乔木花粉平均含量均<10%,草本植物花粉>80%,灌木植物花粉<1%.洛南盆地表土孢粉总浓度平均为1.42×105粒/g,与植被覆盖度关系较弱,而与植被类型有一定联系,能辅助植被类型的辨识.聚类分析和PCA分析都能较好区分森林和非森林植被,前者能较好地区分松林和混交林,后者能较好地区分农田和灌、草丛植被,且比聚类分析更加稳定.松属、栎属等乔木花粉具有较强的扩散能力,能指示区域植被,松属没有表现出很强的超代表性,栎属具有低代表性;蒿属花粉与植被覆盖度间的相关关系较差,具有明显的超代表性,其大量出现与人类的干扰有一定的联系,禾本科花粉具有很好的植被指示性和低代表性,藜科花粉的高含量主要指示了高强度的人类活动;中华卷柏孢子在地层中的大量出现具有指示森林或松林环境的意义.  相似文献   

8.
天山乌鲁木齐河源区大西沟表土花粉散布特征   总被引:13,自引:5,他引:13  
在天山乌鲁木齐河源区大西沟垂直植被带表土孢粉分析及植被调查的基础上,对大西沟垂直带的植被与表土孢粉的关系进行了探讨。从表土孢粉百分比含量可划分出4个孢粉带,其对应的植被带分别为高山垫状植被、高山草甸、亚高山草甸和云杉(Picea)林带。孢粉百分含量基本上反映了大西沟地区垂直植被带分布的特征。云杉、麻黄(Ephedra)、藜科(Chenopodiaceae)和蒿属(Artemisia)等植物花粉明显表现为超代表性。山谷上升气流在天山山地垂直植被带的表土孢粉散布中起着重要的作用。  相似文献   

9.
青藏高原是我国重要的高寒草甸分布区和畜牧区,畜牧活动对区域植被和生态的影响作用受到众多学者的广泛关注。通过采集青藏高原东部高寒草甸区共49个放牧家畜粪样品(牦牛粪样品30个、马粪样品11个、羊粪样品8个),并在区域植被调查的基础上,对粪样品开展了花粉分析。结果表明:这3种类型的粪样品花粉组合以莎草科(Cyperaceae)、禾本科(Poaceae)、龙胆科(Gentianaceae)、毛茛科(Ranunculaceae)花粉为主,可较好地反映区域植被群落特征,食草动物粪花粉中有少量谷物类禾本科花粉出现反映了当地居民少量耕种燕麦用来饲养牲畜。3种放牧家畜在采食习性上存在一定差异,牦牛采食的植物种类比羊和马略多,牦牛和马对杂草类禾本科和唐松草属植物的采食率低于羊,对龙胆科、菊科和蒿属植物的采食率明显高于羊。放牧家畜通过选择性采食适口性好的莎草科和禾本科优势植物种类直接影响高寒草甸区植被群落结构和功能。研究区粪花粉组合与表土花粉组合对比发现,乔木花粉和紫菀属花粉含量在表土样品中显著高于粪样品,而禾本科和龙胆科花粉含量在粪样品中高于表土样品,上述差异指示粪花粉更能反映区域植被群落特征,放牧家畜选择性采食导致粪花粉与表土花粉组合有所区别。本研究为评估青藏高原放牧家畜采食习性以及畜牧活动对区域植被的影响提供了新的研究思路和手段,也为今后在青藏高原开展考古遗址中保存的粪样品花粉分析,据此重建古植被群落和古人类生产活动信息,提供了重要的现代过程依据和借鉴资料。  相似文献   

10.
新疆夏尔希里自然保护区保持着较为原始的生态环境,是研究植被与环境变化的理想区域。通过在保护区内从海拔1 042~2 426 m的山地草原化荒漠带、山地干草原带和山地森林带采集的33个表土孢粉样品,结合对每个样点做的植被样方调查,根据孢粉数据进行有序聚类分析和冗余分析,探讨了表土孢粉组合特征与植被之间的对应关系。结果表明:3个孢粉组合带的特征与各垂直带植被总体上有较好的对应;藜科和麻黄属花粉含量与样方植物盖度无明显相关性,这两类孢粉呈现超代表性分布特征,应该是随气流从低海拔地带传播到山地高海拔地带的区域外花粉;桦属花粉和豆科花粉与对应的桦木林及锦鸡儿灌丛植被群落有较好的对应;A/C比值和孢粉总浓度大小在区分森林带与草原化荒漠植被带时有明显的指示意义;蕨类植物孢子与降水量和海拔高度正相关,豆科植物花粉与温度正相关。由于山地地形因素引起的土壤、水分及光照度差异,在相同海拔高度的阳坡与阴坡形成的森林植被和中山草甸植被交替的过渡植被,因此孢粉组合中出现较多的花粉混合,进而降低了云杉和桦属花粉与植被盖度的相关性,这类木本花粉与植被之间的数量关系较为复杂。该现象在植物生态学分析中具有普遍性,但对表土孢粉数据在植被与气候定量重建中的应用具有较大的影响。在运用山地表土孢粉数据进行植被与气候定量重建时,需要结合植被样方资料和沉积环境特征对表土孢粉数据进行校正和筛选。  相似文献   

11.
The catchment of South Luohe River in Central China is an important region for investigating modern pollen-environment relationship, because it is located in the transitional zone between south and north China, an environment which is sensitive to climate changes. In this study, 40 surface samples under ten vegetation types were collected to reveal the relationship between pollen assemblages and vegetation. The results show that the surface pollen assemblages reflect the vegetation quite well. In forest topsoils, the average of arboreal pollen content is greater than 40%, and the Selaginella sinensis spore is high. As to sparse forest grassland and shrub community, the average arboreal pollen is 13.2% and 16.6% respectively, and the shrub pollen is relatively higher than that of grassland samples. The grassland and farmland are characterized by low percentage of tree and shrub pollen (<10% and <1%), and high percentage of herbs (>80%). Pinus, Quercus and some other arboreal pollen can indicate the regional vegetation because of their dispersal ability. Quercus pollen is under-representative and so is Pinus. Artemisia pollen is significantly over-represented, has poor correlation with the plant coverage, and may reflect human disturbance. Gramineae can indicate plant quite well, but with low representation. High content of Chenopodiaceae probably suggests human impact. Predominant Selaginella sinensis can be used as an indicator of forest environment. Cluster analysis and principal components analysis of pollen assemblages can distinguish forest and non-forest vegetation well. The former method is better at separating pine and mixed forests, while the latter is more stable and could better differentiate farmland and other non-forest area. The first axis of PCA mainly reflects the humidity.  相似文献   

12.
The catchment of South Luohe River in Central China is an important region for investigating modern pollen-environment relationship, because it is located in the transitional zone between south and north China, an environment which is sensitive to climate changes. In this study, 40 surface samples under ten vegetation types were collected to reveal the relationship between pollen assemblages and vegetation. The results show that the surface pollen assemblages reflect the vegetation quite well. In forest topsoils, the average of arboreal pollen content is greater than 40%, and the Selaginella sinensis spore is high. As to sparse forest grassland and shrub community, the average arboreal pollen is 13.2% and 16.6% respectively, and the shrub pollen is relatively higher than that of grassland samples. The grassland and farmland are characterized by low percentage of tree and shrub pollen(<10% and <1%), and high percentage of herbs(>80%). Pinus, Quercus and some other arboreal pollen can indicate the regional vegetation because of their dispersal ability. Quercus pollen is under-representative and so is Pinus. Artemisia pollen is significantly over-represented, has poor correlation with the plant coverage, and may reflect human disturbance. Gramineae can indicate plant quite well, but with low representation. High content of Chenopodiaceae probably suggests human impact. Predominant Selaginella sinensis can be used as an indicator of forest environment. Cluster analysis and principal components analysis of pollen assemblages can distinguish forest and non-forest vegetation well. The former method is better at separating pine and mixed forests, while the latter is more stable and could better differentiate farmland and other non-forest area. The first axis of PCA mainly reflects the humidity.  相似文献   

13.
通过对浙江嵊州西白山香榧林、针阔混交林、茶园及竹园16份苔藓的花粉分析,研究其表土花粉与现代植被的关系。结果表明:① 研究区植物孢粉共由50科属组成,以乔木花粉(主要为香榧和马尾松)为优势,含量为71.5%~92.9%,草本花粉次之,含量为5.3%~24.7%,蕨类孢子含量最低,含量为1.5%~7.2%,表土花粉组合基本上反映了该区植被的总体特征;② PCA结果显示,香榧和香榧林均能很好的区分出来,说明其具有很好的分异性;③ 香榧花粉在香榧林的含量较高,平均高达41.1%,但在林外,其含量则迅速降低,为5.2%~9.8%,可见香榧花粉的传播距离非常有限。该结果建议当地层中香榧花粉化石的含量达到10%,就可以初步断定在研究区附近有古香榧林的存在。  相似文献   

14.
黑河中游现代孢粉传播过程研究   总被引:1,自引:0,他引:1  
常婧  惠争闯  耿豪鹏  胡小飞  潘保田 《地理科学》2017,37(12):1925-1932
在位于河西走廊的黑河中游地区选取8个河流沉积样品和7个表土样品进行孢粉分析,通过其孢粉百分含量分别探讨河流与风力搬运对孢粉传播的影响。结果表明:风力对孢粉具有较强的搬运能力,能够将区域外或上游山地植被孢粉搬运至中游地区,但其对当地孢粉贡献较小,一般低于10%;河流搬运孢粉的能力大于风力,能够将上游山地植被孢粉大量的搬运至研究区,外来孢粉含量最高可达39.4%,成为孢粉谱的重要成分。表土孢粉组合能够较好的反映研究区现代植被的分布情况;河床沉积物孢粉组合反映的是上游山地植被和研究区植被混合状况。  相似文献   

15.
 蒙古国北部Gun Nuur湖20个表层沉积物孢粉组合与数量分析研究揭示,孢粉组合及浓度分布存在显著空间差异。结果表明:双束松型花粉百分含量由湖泊东南向西北降低,桦属、蒿属、藜科以及禾本科百分含量增加,湖泊东南侧赤松林是造成孢粉组合空间分异的主要原因。孢粉浓度分布与湖泊水深具有良好的对应关系,体现了湖水流对孢粉的二次搬运和富集作用。现代森林草原地带Gun Nuur湖表层孢粉组合中松属含量较高,具超代表性;受松属影响蒿属和藜科花粉含量较低,代表性较低。  相似文献   

16.
神农架巴山冷杉林花粉与植物关系及其森林植被之演替   总被引:24,自引:0,他引:24  
李文漪 《地理学报》1991,46(2):186-194
在神衣架巴山冷杉林中,冷杉花粉数量与其植物盖度接近。在林外,冷杉花粉数量迅速下降,至10km以外则仅有个别出现。用在表土中所取R值对化石花粉组合谱进行了校正。说明现代的巴山冷杉林乃是由栎—桦林演变而来,时间约在300—400BP。  相似文献   

17.
The objective of this study is to investigate pollen-vegetation relationship in the Qilian Mountains. The eastern Qilian Mountains are located in the transitional zone of the Tibetan Plateau, the Loess Plateau and the arid region of Northwest China, which is one of the key areas of global environmental change. A total of 13 surface pollen samples from main vegetation have been collected. Pollen percentages were calculated in all samples. In order to reveal the relationship between pollen composition and the vegetation types from which the soil samples have been collected, Detrended Correspondence Analysis (DCA) ordination method was employed on the pollen data. The results show that dominating vegetation types can be recognized by their pollen spectra: Picea crassifolia forest, alpine shrub and alpine meadow as well. Altitude and temperature determine the distribution of the surface pollen and the vegetation. The good agreement between modern vegetation and surface samples across this area provides a measure of the reliability of using pollen data to reconstruct paleoenvironment and paleovegetation patterns in this or other similar regions. However the loss of Betula pollen in forest needs further investigation. Pollen oxidation is the most important factor contributing to the damage of modern pollen in the study area. Pollen concentrations decrease with the increase of pH values of soils, and decrease sharply when the pH exceeds 7.6.  相似文献   

18.
东祁连山南坡现代花粉雨与植被   总被引:1,自引:0,他引:1  
1 Introduction A significant problem in the analysis of pollen spectra is the incomplete comprehension of the relationship between modern pollen spectra and the vegetation that produces them. Pollen precipitation reflects many factors: pollen production,…  相似文献   

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