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1.
广西南宁空气中孢粉及其致敏性研究   总被引:2,自引:0,他引:2  
本文通过空气中的孢粉调查,选用32种花粉对呼吸道过敏患者进行皮肤敏感试验,既阐明了南宁市空气中孢粉散布的基本规律,讨论空气中花粉含量与气候的关系,也明确了该市主要致敏花粉是蒿属、禾本科、藜科及桑科植物的花粉,为呼吸道过敏性疾病的预防、诊断及治疗提供了重要依据。  相似文献   

2.
滦河流域及周边地区花粉与植被关系的研究   总被引:3,自引:0,他引:3       下载免费PDF全文
滦河流域及周边地区空气中的花粉组合基本上反映了当地的植被面貌, 与植物的花期相对应, 乔木植物的花期多在春季, 草本植物的花期多在夏秋季, 该地冬季基本上无植物开花, 冬季空气中的花粉应是当年或多年春、夏、秋季散落在地上又被风吹到空气中的表土花粉和一些外来花粉 ;表土花粉随海拔高程的降低依次出现山地草甸、针阔混交林或以针叶树为主的针阔混交林、山地灌草丛、滨海平原草甸和滨海草甸或滨海盐生草甸的等 5个花粉组合带, 分别为蒿 (Artemisia)唐松草 (Thalictrum)松(Pinus)桦 (Betula) 孢粉组合带、松桦栎 (Quercus) 蒿孢粉组合带、藜科 (Chenopodiaceae)蒿禾本科 (Gramineae)中华卷柏 (Selaginellasinensis) 孢粉组合带、藜科蒿菊科 (Com positae)香蒲 (Typha) 孢粉组合带和藜科蒿莎草科 (Cyperaceae)禾本科孢粉组合带 ;由于花粉在河水中是以悬移质颗粒被搬运, 因此在不同时期沉积物花粉组合存在着一定的差异, 其中洪水期间河水对孢粉的分选作用最为明显。  相似文献   

3.
中国早第三纪孢粉植物群纲要   总被引:13,自引:0,他引:13  
张一勇 《古生物学报》1995,34(2):212-227
简要地叙述中国大陆及陆架区早第三纪孢粉植物群的纵向演变和横向分异,将纵向演变归纳为6个主要的孢粉植物群发展时期。即:1)早古新世榆科花粉发育期;2)晚古新世正型粉扩展期;3)早始新世榆科-桦科-胡桃科花粉繁盛期;4)中始新世壳外科花粉发育期;5)晚始新世蒺藜科花粉扩展期;6)渐新世松科花粉发育期。据横向地区差异,将中国大陆及陆架区划分为7个早第三纪孢粉植物地理区,为:1)东北暖温带至亚热带湿生孢粉植物区,2)华北暖温带至亚热带中生孢粉植物区,3)西北暖温带至亚热带旱生孢粉植物区,4)中南亚热带中生孢粉植物区,5)东海南部陆架亚热带湿生孢粉植物区,6)南方亚热带、热带中生至湿生孢粉植物区,7)西藏亚热带中生孢粉植物区。对以上各期的孢粉植物区的主要特征和各地理区范围,代表性的孢粉和特征分别进行叙述,并以此对中国早第三纪的主要含孢粉地层列表进行了对比。  相似文献   

4.
本文对云南省香格里拉地区(海拔3 400~4 700 m)7个植物群系下采集的21个现代苔藓样品进行了孢粉研究,探讨了现代孢粉组合与样点周围植被之间的关系,以及主要孢粉类型的代表性与传播能力。结果表明,香格里拉地区不同植物群系的孢粉组合具有不同的代表性成分与变化特征,能较好地反映当地植被状况。桦木林和黄背栎林的孢粉组合中指示性成分分别是高含量的桦木属和常绿栎类花粉;冷杉林下的样品,除采自仅有稀疏冷杉的冷杉林下的样品外,其他样品的孢粉组合都较好地反映了高含量的冷杉属花粉;杜鹃灌丛和蔷薇灌丛的孢粉组合分别以高含量的杜鹃花科和蔷薇科花粉为特征;在花粉产量低且植被较开阔的流石滩疏生草甸中,孢粉组合以高含量的草本花粉和外来乔木花粉(如松、冷杉等)为主。松属花粉在本研究区各植物群系下所有样品的孢粉组合中均有较高含量,说明松属花粉产量高、传播能力最强,具有超代表性;铁杉属和桤木属花粉也具有较强的传播能力,它们是外来花粉的主要成分,在不同植物群系下其花粉含量的高低与当地植被的郁闭度及当地植被花粉产量有关;桦木属和常绿栎类花粉代表性强,花粉产量高,也具有较强的传播能力;冷杉属花粉具有明显的低代表性,但其传播能力较强;杜鹃花科花粉的代表性较好,但传播能力差,其花粉散布范围基本在有母体植物生长的地方;柳属花粉代表性低,其花粉含量高于1.0%可能指示柳树的存在;单裂缝孢子的蕨类植物在本研究区部分样品中有较高含量,说明单裂缝孢子的蕨类植物比三裂缝孢子的蕨类植物可能更能适应海拔3 400 m以上的高海拔环境。  相似文献   

5.
燕山地区表土花粉与植被间的数量关系   总被引:25,自引:0,他引:25       下载免费PDF全文
 根据表土花粉分析和植被样方调查,燕山地区各植被带的表土孢粉组合在总体面貌上代表了植被组成,但孢粉组合不等于植被组成,而影响其差异的原因是孢粉保存、孢粉产量、外来孢粉和孢粉鉴定。表土花粉的代表性因种属不同而差异颇大,乔木植物花粉中松(Pinus)、桦(Betula)、胡桃  相似文献   

6.
中国古生物学会孢粉学分会第七届二次学术年会于2007年6月5日—8日在石家庄河北师范大学顺利举行。来自全国各科研院所、高等院校和石油、花粉资源开发、出版行业等系统的100多位代表出席了本次会议。会议共收到论文摘要67篇,学术报告55个。内容涉及早期生命、几丁虫、生物地层、孢粉相、古植被与古环境、第四纪孢粉与环境、考古、表土花粉、空气孢粉、花粉形态学与系统演化、埋藏学、花粉营养学、数据库、植硅体和硅藻等众多方面。反映了中国孢粉学在近年所取得的丰硕成绩。朱日祥院士和郑卓教授分别作了题为“早期人类与环境”和“中国表…  相似文献   

7.
本文对云南泸沽湖周边山地不同植被类型下采集的32个表土样品和36个泸沽湖湖泊表层样品进行了孢粉分析,探讨了不同植被类型内的表土孢粉散布特征,对比分析了山地表土与湖泊表层孢粉分布特征的差异。结果表明,不同山地植被类型的孢粉组合具有不同的代表性成分与变化特征,能够较好地反映相应的植被类型。湖泊表层孢粉研究表明,湖泊内不同位置的孢粉组合差异较小,说明湖泊表层孢粉反映的是区域植被的平均分布状况。对比分析泸沽湖周边山地表土与湖泊表层样品的孢粉组合,两者存在一定的差异,表现为:湖泊表层的孢粉组合中乔木花粉(主要是松属)平均含量比表土高,但波动范围要小;草本花粉平均含量要低,且波动范围也小。这可能是由于乔木植物植株较高,而且有些乔木植物花粉具有气囊,更易借助风力将花粉传播到比较远的湖泊中的原因造成的。冷杉和铁杉花粉在所有样品中含量都相对较低,分别不高于6.5%和3.6%;桦属、桤木属、常绿栎类花粉的最高值出现在有这些母体植物生长的表土样品中,在其他样品中则明显较低。在表土孢粉样品中经常可以见到冷杉的气孔器,但在湖泊表层样品中却没有见到,说明气孔器不易到达湖泊中。该研究是对中国西南表层孢粉研究的有益补充,同时为泸沽湖新生代特别是第四纪化石孢粉解释提供了可靠的参考和依据。  相似文献   

8.
中国晚白垩世孢粉植物群   总被引:12,自引:4,他引:8  
本文根据我国已发表的资料,综合分析研究了我国各地晚白垩世及早、晚白垩世时限前后的孢粉植物组合,特别对其中的被子植物花粉演进序列进行了探索,并和北半球五个主要的晚白垩世孢粉植物发育地区(加拿大西部,美国东部、中西部,东欧,前苏联远东地区)连续的晚白垩世被子植物花粉演化序列进行了对比研究,提出我国晚白垩世孢粉植物群发展基本上可分为四个主要阶段,即(1)前短轴类被子花粉发育期,(2)短轴类被子花粉发育期,(3)进化被子花粉发育期,(4)脊榆粉发育期,它们发育的时限分属于赛诺曼期(Cenomanian),土仑期至桑托期(Turonian-San-tonian),坎佩尼期(Campanian)和马斯特里赫特期(Maastrichtian)。根据孢粉植物群特征和其所反映的古气候,将我国晚白垩世孢粉植物群分为两个孢粉植物地理区,即;东北中生孢粉植物区和西北—东南旱生孢粉植物区,后者又分为西北亚区和东南亚区。  相似文献   

9.
在新疆阿尔泰山中段的红山嘴地区选取一条沿海拔745-2 413 m的不同植被带群落样方进行调查, 对应采集37个表土样品进行孢粉统计和排序分析, 初步探究了红山嘴地区的植被与表土孢粉之间的对应关系, 并将之与新疆阿尔泰西部的喀纳斯西坡孢粉垂直带进行对比。结果表明, 红山嘴地区表土孢粉谱依照海拔高度自上而下划分为4个孢粉组合类型, 分别对应亚高山草甸、山地森林、灌丛草原和荒漠草原。乔木植物中云杉属(Picea)和松属(Pinus)花粉, 灌木植物中麻黄属(Ephedra)及草本植物中的苋科和蒿属(Artemisia)因受到自然风力、水流及人为活动的影响, 表现出明显的超代表性; 乔木植物中的落叶松属(Larix)花粉, 草本植物中的禾本科及莎草科花粉, 却在其自身为优势种的群落中呈现低代表性; 蒿属与苋科花粉百分含量的比值(Ar/Am)能较好地反映该区气候垂直带的干湿状况, 灌丛草原带的Ar/Am低, 在一定程度上反映了人类活动对草原灌丛化的影响。与新疆阿尔泰西部的喀纳斯西坡孢粉垂直带相比, 红山嘴垂直带的孢粉类型偏少, 同时相似的孢粉带在该区的分布高度比喀纳斯西坡高。此外, 排序分析(RDA)结果表明, 年降水量是影响该区表土孢粉组合的主要环境因子。  相似文献   

10.
孢粉-植被-气候关系研究进展   总被引:20,自引:0,他引:20       下载免费PDF全文
随着全球变化研究的不断深入 ,第四纪孢粉学研究已取得了长足的进步 ,特别是近些年来 ,孢粉 植被 气候关系研究已成为世界孢粉学界的热点之一。空气孢粉学的研究在大气环境污染监测、花粉过敏症、农业收成预报和第四纪植被与环境重建等方面得到了广泛应用 ,并不断发展 ;近年来 ,为开展全球范围的古环境研究 ,各大洲相继建立了孢粉数据库 ,大量开展表土孢粉研究。中国第四纪孢粉数据库的建立 ,汇集了我国近半个世纪积累的孢粉资料 ,并利用中国第四纪孢粉数据 ,系统开展了中国现代表土孢粉、6kaBP(中全新世 )及 1 8kaBP(末次盛冰期 )的生物群区模拟及重建 ,建立了花粉 气候转换函数和响应面模型 ,并取得了良好的结果 ;冲积物孢粉学和环境考古孢粉学研究 ,也取得了一定成果 ,但研究还有待于深入 ;特征指示种花粉雨研究 ,对古生态环境重建也具有重要的意义。  相似文献   

11.
Guangxi Zhuang Autonomous Region is a subtropic monsoon climate. Plants are various and their blossom period are long. To prevent and cure the respiratory allergic diseases, we made an investigation on the diffusion patterns of airborne allergic pollen grains and spores and their allergization as well in Nanning. Our work paves a way for further similar researches in the south of our country. The relationship between airborne pollen quantity and the climate, the diffution patterns of various pollen grains and the pollen quantity of higher level and lower level are discussed in the present paper.  相似文献   

12.
《Biophysical journal》2022,121(5):782-792
The structure of pollen grains, which is typically characterized by soft apertures in an otherwise stiff exine shell, guides their response to changes in the humidity of the environment. These changes can lead to desiccation of the grain and its infolding but also to excessive swelling of the grain and even its bursting. Here we use an elastic model to explore the mechanics of pollen grain swelling and the role of soft, circular apertures (pores) in this process. Small, circular apertures typically occur in airborne and allergenic pollen grains so that the bursting of such grains is important in the context of human health. We identify and quantify a mechanical weakness of the pores, which are prone to rapid inflation when the grain swells to a critical extent. The inflation occurs as a sudden transition and may induce bursting of the grain and release of its content. This process crucially depends on the size of the pores and their softness. Our results provide insight into the inactive part of the mechanical response of pollen grains to hydration when they land on a stigma as well as bursting of airborne pollen grains during changes in air humidity.  相似文献   

13.
The seasonal incidence of pollen in the atmosphere of Brisbane has been established from a near-continuous, volumetric trapping program over the five-year period, July 1994-June 1999. Grass pollen accounts for 71.6% of the average annual pollen load with highest densities (up to 150 grains/m 3 ) recorded in summer and autumn. Significant contributions were also made by taxa of the Cupressaceae (8.7%) and Urticaceae (1.8%) during spring and of the Pinaceae (4.5%) during winter. Pollen seasons of the Casuarinaceae (6.5%) and Myrtaceae (3.2%) are more extended, the former peaking in late winter and the latter in late spring. The onset and duration of the Poaceae and Urticaceae seasons varied from year to year, being later when precipitation levels were low in the late spring-early summer months. Total pollen numbers and grass pollen densities are substantially less than those recorded from southern Australia. Nevertheless, respiratory disease in Brisbane affects up to 10% of the population, and airborne pollen of Poaceae, Urticaceae, Cupressaceae, Pinaceae, and Myrtaceae have been implicated in the release of allergens.  相似文献   

14.
We developed a novel flow particle analyzer that automatically classifies airborne pollen grains. The design of the particle counter (model KP-1000) is based on that of a flow cytometer, applied to the measurement of airborne particles. The counter classifies pollen species by simultaneously detecting both scattered light and the characteristic fluorescence excited by ultraviolet light in the flow cell. We observed airborne pollen using KP-1000 pollen counters and Durham samplers to compare their performance at three study sites in Japan during the spring pollen season. The pollen counter followed the variation in pollen concentrations, and its daily pollen counts were significantly correlated with the results of the Durham sampling method at all study sites. Although the counter over- or under-counted 2 target pollen species (Cryptomeria japonica and Chamaecyparis obtusa) when they coexisted, a data correction based on the Durham sampling results improved the accuracy of pollen classification of the counter. Our results indicate that the new pollen counter has a strong potential for counting and identifying airborne pollen grains in real time, and it requires further improvement, field trials, and tests with other common airborne pollen grains.  相似文献   

15.
Oleaceae pollen concentrations in the Trieste area are low (<10%) compared to the total number of airborne pollen grains, with only one pollination peak at the beginning of June when the Oleaceae concentration reached 62% of the total pollen count in 1992. This peak was due to an exceptionally high pollination of olive trees in 1992, when airborne pollen concentration rose to 1357 pollen grains/m3 on June 3. Sensitization toOlea increased from 1989 to 1993, when it was present in 23.4% of symptomatic patients, but the role ofOlea in inducing allergic respiratory symptoms is difficult to evaluate because almost all patients were sensitized to other pollens, and in particular to Gramineae: only four subjects were sensitized toOlea alone (1.4%). Despite the low Oleaceae pollen counts, this pollinosis is increasing, probably because of increased cultivation ofOlea in recent years. However, although skin prick test positivity is common in polysensitized patients, its role in inducing sensitization and symptoms is presently less important than that of other pollens.  相似文献   

16.
A survey of airborne pollen was conducted during 1984 in the coastal plain of Israel. The flora of that area is continuously changing due to urbanization and agriculture, thus affecting the airborne pollen spectrum.

Significant pollen counts were monitored throughout the year, with a seasonal peak during spring. Meteorological parameters, such as wind velocity, wind direction and temperature affected pollen content of the air. Under certain conditions, even pollen of insect-pollinated plant species was found in the air.

The most conspicuous among the airborne pollen were olive, cypress and pine trees as well as pollen grains from the Poaceae, Amaranthaccae, Chenopodiaceae, Asteraceae, Brassicaceae and Urticaccae.

Results indicate that most of the airborne pollen grains were of local origin and from cultivated trees. Thus, it is possible to reduce airborne pollen contaminants around human habitations by selection of the proper non-allergenic ornamental plants.  相似文献   

17.
The number and degree of digestion of pollen grains in the midgut and rectum, the midgut proteolytic activity and the time of pollen grain passage through the digestive tract in the stingless bee Scaptotrigona postica (Latreille) have been analyzed. The results show similar protein requirements among larvae, nurse bees and queens, as well as between forager bees and old males, but these requirements are higher in individuals from the former groups than in those from the latter. Although protein requirements have been demonstrated to vary according to a bee's activity in the colony, they are similar among bees from different castes or sexes. These changes in feeding behavior are related to the bee's function and to less competition for nourishment among individuals of the colony. It is also noted that pollen grains took between 6 and 28 h to pass through the digestive tract. Pollen grains are irregularly accumulated in the various regions of the midgut, which may reflect functional differentiation throughout the midgut.  相似文献   

18.
The worldwide human population suffering from allergies continues to increase. Pollen grains are a major source of airborne allergens and significant cause of these diseases. Therefore, continuous monitoring of pollen grains released and transported in the air locally or regionally is required to determine the prevalence of various pollen types and identify intra-day and intra-annual seasonal variations over time. In this study, we developed the first pollen calendar for Mexico City, which includes a large variety of taxa, many of which show a long Main Pollen Season which may last throughout the year. The analysis and comparison of daily, monthly and annual values showed that the occurrence and abundance of the main types of aero-allergenic pollen in the atmosphere were species of Fraxinus, Cupressaceae and Alnus, which occur during the periods from December through March, whereas airborne pollens of several species of Poaceae and Urticaceae occurred throughout the year. The variation in pollen concentration showed that the greatest intra-diurnal variations occurred during the second half of the day. Regarding the relationship of pollen with bioclimatic factors, the increase in temperature favoured the presence of pollen in the air, whereas the increase in pluvial precipitation and relative humidity was associated with a decrease in airborne pollen. Large tracts of the Valley of Mexico have atmospheric conditions that are conducive to the accumulation of airborne particles, including pollen. Anomalous winds from the southeast dominated the surface wind variability during the first months of 2010. These patterns induced extreme values in wind convergence at the lower levels of the atmosphere, which resulted in high concentrations of pollen at our sampling site. We suggest that these conditions are related to the warm phase of the El Niño Southern Oscillation phenomenon (2009–2010).  相似文献   

19.
This paper reports on pollen analyses carried out in the course of a ten-year investigation, on many thousands of cytological smears coming from various organs and systems of the human body, and prepared for diagnostic purposes. The frequency and the significance of the pollen records vary according to the specific cytological field taken into account. In the urinary sediment smears, nipple secretions, and needle aspirations the polliniferous smears are very few, and the pollen number per smear is low (max 14 pollen grains, belonging always or mostly to anemophilous species). In these cases, the pollen records evidence the airborne contamination during medical procedures, the same happens with most of cervico-vaginal smears. In some cervico-vaginal smears, the high frequency of pollen grains belonging to pharmaceutical taxa suggests that lavages with vegetable components were used by the patients before undergoing the test. In nasal, bronchial and conjunctival cytology greater amounts of polliniferous slides were recorded (in bronchial/nasal cytology also a higher number of pollen grains per smears, up to 114–428 respectively) and pollen spectra reflected the vegetational environment of the patients' living sites. In these cases, most pollen grains are thought to be really present on mucosae when the samples were taken. In these cytological fields pollen analysis may be useful for diagnostic purposes, above all in case of allergic pathology to detect the pollen grains causing the disease.  相似文献   

20.
Pollen monitoring is an important and widely used tool in allergy research and creation of awareness in pollen‐allergic patients. Current pollen monitoring methods are microscope‐based, labour intensive and cannot identify pollen to the genus level in some relevant allergenic plant groups. Therefore, a more efficient, cost‐effective and sensitive method is needed. Here, we present a method for identification and quantification of airborne pollen using DNA sequencing. Pollen is collected from ambient air using standard techniques. DNA is extracted from the collected pollen, and a fragment of the chloroplast gene trnL is amplified using PCR. The PCR product is subsequently sequenced on a next‐generation sequencing platform (Ion Torrent). Amplicon molecules are sequenced individually, allowing identification of different sequences from a mixed sample. We show that this method provides an accurate qualitative and quantitative view of the species composition of samples of airborne pollen grains. We also show that it correctly identifies the individual grass genera present in a mixed sample of grass pollen, which cannot be achieved using microscopic pollen identification. We conclude that our method is more efficient and sensitive than current pollen monitoring techniques and therefore has the potential to increase the throughput of pollen monitoring.  相似文献   

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