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1.
太白山北坡花粉通量与表土花粉研究   总被引:5,自引:0,他引:5  
太白山北坡各森林植被带乔木花粉百分比多高于45%,与植被组成类似。高山草甸带捕捉器样品乔木花粉百分比低于15%,与植被组成一致,但表土花粉组合中乔木花粉百分比高于50%,外来花粉数量较多,进行高山带古环境研究应予注意。太白红杉林花粉通量最低,高山灌丛草甸最高。落叶栎林带表土花粉浓度最低,红桦林带最高。表土中松、冷杉属花粉百分比远高于花粉捕捉器,表明其在表土中有较好的保存能力。落叶松属和杜鹃花科花粉在表土及捕捉器中百分比均较低,表明对植被指示性良好。栎属与桦属花粉通量类似,但桦属花粉浓度大于栎属,表明栎属较桦属易于保存。  相似文献   

2.
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   

3.
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   

4.
白洋淀湖面捕捉器样品、湖底捕捉器样品和湖泊表层沉积物样品花粉组合及花粉通量均能较好地反映地方和区域植被特征。湖面捕捉器花粉通量明显低于湖底捕捉器,通过对比湖面、湖底捕捉器花粉通量,发现白洋淀湖泊有91%以上的花粉由地表径流携带而来。判别分析结果表明:湖水和空气在花粉传播和沉积过程中均存在对花粉的搅匀和混合作用,样品类型间花粉组合差异大于样点间差异,花粉来源途径的不同对湖泊花粉组合影响明显。  相似文献   

5.
对尼洋河流域5个不同植被带下18个表土样品的孢粉分析结果显示:不同植被带下表土花粉组合差异显著,表土花粉组合与现代植被带在空间分布、建群种和优势种属方面基本一致,两者对应结果分别为:高山草甸为莎草科组合带;亚高山灌丛为沙棘属-蒿属组合带;高山栎林为栎属-蔷薇科-蒿属组合带;高山松林为松属组合带;针阔混交林为松属-冷杉属-蒿属组合带。年均降水量(MAP)是影响尼洋河流域表土孢粉组合的重要因素。草本、乔木花粉百分含量与研究区MAP值呈显著相关,草本花粉的百分含量与MAP值呈明显负相关,而乔木花粉则相反。研究区孢子和花粉浓度不一定随MAP增加而显著增加。  相似文献   

6.
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   

7.
浙江庆元百山祖地区拥有中国最典型的中亚热带常绿阔叶林以及山地生态系统完整的垂直带谱,基于对该区海拔高度300~1 700 m所采集的9个表土花粉样品的孢粉组合图式,探讨该区植被与表土花粉之间的关系。结果表明,该区表土花粉谱按照海拔从高至低可划分为3个孢粉组合带,分别对应于常绿落叶阔叶混交林和温性针叶林、常绿阔叶林和暖性针叶林带以及次生针阔混交林林和农田地带(人类活动干扰导致),以松属(Pinus)、栲属(Castanopsis)、栎属(Quercus)等木本植物占优势,以里白属(Hicriopteris)和水龙骨科(Polypodiaceae)为主的蕨类植物也较多。该区冷杉属(Abies)花粉含量和产量都较低,可能与目前百山祖冷杉数量较低及其分布范围相对较窄有一定关系。此外,基于孢粉复合分异度指数的孢粉多样性的分析结果表明,人类干扰因素导致该区较低海拔的表土孢粉不能反映区域的地带性植被。  相似文献   

8.
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   

9.
吕新苗  陈辉  李双成  郑度 《山地学报》2004,22(2):199-206
应用TWINSPAN分类和DCA排序对东祁连山地区7个不同植被类型的表土花粉组合及其与环境的关系进行定量研究。表土花粉类型可分为3组:Group1为花粉产量大的本地花粉,可较好地反映当地植被的特征;Group2为产量小的本地花粉,反映植被特征较差;Group3为外来花粉,在土壤地层中较常见。样地排序结果可划分出6个组:(1)山地草原化荒漠,(2)青海云杉林,(3)祁连圆柏林,(4)金露梅灌丛,(5)矮嵩草草甸,(6)小嵩草草甸,各组具有不同的花粉组合特征;但山杨—白桦林可能是由于花粉自身和花粉保存等原因,花粉组合无突出特征,难以区分。海拔高度和干燥度是影响表土花粉和植被分布的重要因素。藜科/蒿属(C/A)、木本花粉/非木本花粉(AP/NAP)随植被变化也反映出与植被分布的一致性。  相似文献   

10.
北方草原区主要群落类型表土花粉分析   总被引:38,自引:2,他引:36  
建立花粉与现代植被的关系是利用地层沉积物中的花粉记录恢复古植被、古气候研究的基础工作之一。中国北方草原区39个表土花粉研究表明,蒿属、藜科是草原区花粉组合的主要成分,以禾本科为建群种的草原群落花粉组合以蒿属花粉为主,禾本科花粉多低于10%。禾本科花粉的低代表性可能与其分蘖繁殖、花粉产量低有关。草原区表土花粉浓度与植被盖度相关不明显。典型草原与荒漠草原花粉组合存在着明显的区别,典型草原区藜科花粉百分比一般低于25%,荒漠草原区一般高于25%。DCA分析表明,草原区针叶树、莎草科、石竹科花粉代表较湿润的环境,蒿、藜科、锦鸡儿、柽柳、白刺花粉代表较干燥的环境,阔叶树、禾本科、菊科、毛茛科、蓼科、豆科、唇形科(百里香)、虎榛子+榛、蔷薇科花粉代表的环境介于前两组之间。DCA分析用于草原区花粉组合研究具有较好的环境指示意义。  相似文献   

11.
53 pollen traps and surface samples were collected in order to detect the characteristics of pollen assemblages and their relationships with vegetation and climate in 16 forest communities located in 10 mountains in northern China. The results show that 72% of the pollen taxa (80 taxa) are the same between the traps and the surface samples. The dominant taxa in the plant communities are consistent with the main pollen taxa in the pollen assemblages at the same sites. In Pinus plant communities, both Pinus pollen influx and concentration are higher, indicating the high pollen productivity and good pollen preservation ability of Pinus. In Picea and Abies plant communities, Picea and Abies have lower pollen influxes but higher concentrations, suggesting their low pollen productivities but better pollen preservation abilities. In Betula and Quercus plant communities, Betula and Quercus have higher pollen influxes but lower concentrations, revealing their high pollen productivities but poor pollen preservation abilities. The study of relationships between pollen and vegetation with discriminant analysis shows that pollen assemblages from both trap and surface samples can reflect the characteristics of different communities and distinguish different ecological areas, but surface samples can reflect the dominant components of communities much better than the traps. The study on correlations between pollen assemblages and climate with DCCA reveals that significant correlations exist between pollen assemblages and mean temperature of the coldest month (r = 0.84 for trap samples, r = 0.72 for surface samples), and then annual mean precipitation (r = 0.73 for trap samples, r = 0.71 for surface samples).  相似文献   

12.
53 pollen traps and surface samples were collected in order to detect the characteristics of pollen assemblages and their relationships with vegetation and climate in 16 forest communities located in 10 mountains in northern China. The results show that 72% of the pollen taxa (80 taxa) are the same between the traps and the surface samples. The dominant taxa in the plant communities are consistent with the main pollen taxa in the pollen assemblages at the same sites. In Pinus plant communities, both Pinus pollen influx and concentration are higher, indicating the high pollen productivity and good pollen preservation ability of Pinus. In Picea and Abies plant communities, Picea and Abies have lower pollen influxes but higher concentrations, suggesting their low pollen productivities but better pollen preservation abilities. In Betula and Quercus plant communities, Betula and Quercus have higher pollen influxes but lower concentrations, revealing their high pollen productivities but poor pollen preservation abilities. The study of relationships between pollen and vegetation with discriminant analysis shows that pollen assemblages from both trap and surface samples can reflect the characteristics of different communities and distinguish different ecological areas, but surface samples can reflect the dominant components of communities much better than the traps. The study on correlations between pollen assemblages and climate with DCCA reveals that significant correlations exist between pollen assemblages and mean temperature of the coldest month (r = 0.84 for trap samples, r = 0.72 for surface samples), and then annual mean precipitation (r = 0.73 for trap samples, r = 0.71 for surface samples).  相似文献   

13.
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   

14.
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   

15.
对青海湖地区黑马河、泉湾湿地进行了植被样方调查,并由湖岸向外每间隔100~150 m采集表土与苔藓样品进行花粉分析。结果显示,黑马河、泉湾湿地表土花粉与对应样方植被关系密切,花粉组合能较好地反映样方植被特征,同时,桦木属、蒿属、藜科、白刺属、胡颓子科、麻黄科等花粉类型少量出现,为外来花粉。R值分析表明莎草科花粉相对呈高代表性,毛茛科、委陵菜属、禾本科、菊科、报春花科、玄参科等呈低代表性。该研究为在青海湖及其它地区利用花粉重建古植被提供了重要的参考依据。  相似文献   

16.
哈拉湖位于青海省境内祁连山系西部,属于高山内陆湖泊。对哈拉湖域进行了植被样方调查及表土、湖底表层沉积物花粉分析,结果显示该流域表土花粉组合能较好地反映样方植被群落特征,高寒荒漠草原植被样点花粉组合以蒿属、菊科、藜科花粉为主,高寒草甸样点莎草科花粉占绝对优势。R值分析结果显示藜科、莎草科和蒿属花粉具有超代表性,而禾本科、菊科、豆科花粉具有低代表性特征。湖底表层沉积物中的花粉分析结果显示湖泊沉积物花粉受控于湖泊近源植被,花粉组合能较好反映湖区整体植被特征,花粉分布具有均一性。沉积物表层花粉组合以蒿属、藜科为主,双气囊型花粉如云杉属、松属等少量出现,表明河流和风力是哈拉湖沉积物花粉输入的主要动力。该研究为在哈拉湖地区利用花粉重建古植被提供了重要的参考依据。  相似文献   

17.
神农架北坡表土常见花粉的R值研究   总被引:14,自引:4,他引:14  
根据表土孢粉分析和植被样方调查的比较研究,获得了神农架北坡表土常见花粉的R值,常绿阔叶树花粉一般具有较低代表性,R值变化于0.70左右,绝大部分落叶阔叶树花粉也具有较低代表性,R值变化于0.68-0.88之间,但桦,桤木和槭却表现异常,针叶树有气囊花粉具有明显的超代表性,R值变化在1.35-2.44之间,松表现最为强烈,草本植物花粉的R值变化较大,代表性较差,影响R值的因素很多,植物的生态特性,花粉特征,花粉源距离,花粉产量,地形等作用尤为明显。  相似文献   

18.
Sampling of airborne pollen and spores at Ny-Alesund on Spitsbergen in the summer of 1986, by means of a Burkard pollen and spore trap, revealed only very low concentrations of air spora: a cumulative diurnal mean for the whole season of less than 200 pollen grains and just in excess of 9,000 moss and fungal spores. The most frequent pollen types recorded were those of the local taxa: Saxifraga, Salix and Oxyria digyna , whereas the share of pollen of exotic taxa, Betula, Pinus, Juniperus and Alnus , contributed only 9% of the total pollen sum. Back trajectories and pollen registrations at various aerobiological stations in Scandinavia designate central Finland as a possible source area both for the Betula and Pinus pollen. The maximum diurnal mean concentration of Cladosporium was merely 40 spores per m3 air. One may assert that the air at Ny-Alesund is almost free from allergenic pollen and spore types.  相似文献   

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