孢粉-植被-气候关系研究进展

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。     

A taphonomic study of modern pollen assemblages from dung and surface sediments in arid environments of Spain

Coastal plant communities in arid southeastern Spain are characterized by insect-pollinated scrub species, which fail to occur in Quaternary pollen sequences from valleys, marshlands and marine cores. We investigate pollen–vegetation relationships in samples from soil surfaces, animal dung, and sediments in depressions or basins that, in theory, should have pollen spectra that are comparable to those from sedimentary basins elsewhere. Pollen spectra from basins or depressions are very susceptible to long-distance wind and water transport. This can mask representation of pollen from the surrounding insect-pollinated vegetation, as can over-representation of basin-margin halophilous and hydrophilous pollen. Pollen spectra from biogenic materials of animal origin are the best analogues of local and regional vegetation, and show the best analytical potential in terms of pollen concentration and taxon diversity. Pollination properties of the species studied indicate they will rarely be found in most conventional pollen records. It cannot be stressed too strongly that insight into Quaternary vegetation of arid regions demands complementary pollen analysis of coprolites, urine-cemented deposits, and cave sediments with preserved biotic remains, in addition to water-lain sediments.     

中国第四纪晚期孢粉记录整理

孢粉数据库是重建过去植被格局以及研究古气候变化和大气圈-生物圈-人类活动相互关系的基础,而孢粉取样信息的记录和整理是建立孢粉数据库的重要前提。该文在收集我国1960–2008年发表的孢粉研究文献的基础上,整理分析了第四纪晚期,尤其是2万年以来(全新世为主)全国孢粉采样点的信息,包括采样地点名称、详细采样位置、省份、采样点经纬度和海拔高度、样品类型、取样深度、孢粉样品数量、14C测年数量及年代记录、覆盖的时间段和参考文献。总结发现,我国目前共有2324个表土/湖泊表层花粉采样点和987个第四纪晚期的地层沉积剖面和钻孔,其中高质量的地层孢粉采样点714个。虽然我国以及部分国际上从事第四纪研究的科学家尽了最大努力开展中国疆域的孢粉学研究,但由于人力、物力以及地形条件的限制,在我国仍然存在部分孢粉采样的"地理空隙",比如北方和西北荒漠地区、青藏高原无人区、中南部山区和东部人类活动频繁区域。然而,该数据信息库的不断完善,将为中国第四纪孢粉数据库的建立奠定良好基础。     

Spatial variation of pollen deposition in north london

Pollen data from a monitoring network of 14 impact samplers in Islington, North London are used to investigate spatial variations in the abundance of Gramineae, Betula and Platanus pollen deposition. Weekly accumulative pollen counts were collected from January through to October over two consecutive years. Differences in deposition between sites are examined in relation to topography, local sources, and climatic variables.     

Fluorescence microscopy of pollen and spores: a tool for investigating environmental change

Fluorescence microscopy of fossil pollen and spores has only been exploited by palynologists for geological time scales. A reconstruction of ecological change, blanket peat erosion and consequent sediment flux within an area of moorland in the north of England during the late Holocene has provided an opportunity to evaluate whether fluorescence microscopy of pollen and spores can be used as a tool for reconstructing environmental change at shorter and more recent timescales.The fluorescence properties of pollen and spores in samples of blanket peat (sediment source) and reservoir sediments (sediment sink) were assessed during routine pollen counts. Fluorescence varied with taxon. Bog surface processes such as moorland fire and dessication were observed to have no visible effect on fluorescence, but air pollution deposition (indicated by Pb) did have an effect, although exactly which pollutant(s) is responsible is unclear.The effect on fluorescence of the physical processes associated with peat erosion and re-sedimentation in reservoirs was examined. Spores of lower plants found in reservoir sediment samples with a high content of eroded peat were well preserved (fluorescing at blue-green wavelengths), suggesting that the eroded peat was transported from the bog surface to the reservoir as peat fragments containing pollen and spores. There is a direct correlation between the proportions of pollen and spores with extinguished fluorescence (very poor preservation state) in sediment samples, and sediment accumulation rate. This relationship is probably not applicable for quantitatively estimating sedimentation rate at other sites due to the effect of local factors. However, the relationship can provide the basis for a simple, quick and relatively inexpensive method of examining qualitative shifts in sediment flux, which can be conducted during routine pollen counts.     

Morphological studies of the pollen grains of Wadi El-Natrun plants, West Nile Delta, Egypt

Pollen morphology is regarded as an additional tool for solving taxonomic problems at the family, generic, or species level. Seventy-three flowering plants, trees, shrubs, and herbs were collected from the Wadi El-Natrun region (West Nile Delta, Egypt) from March to July 2008. They were extracted for their pollen grains. The pollen was mounted on glass slides, examined using a light microscope, photographed, and identified. The identified pollen grains were conserved in the herbarium of the Environmental Studies and Research Institute (ESRI) Minufiya University, Sadat City, Egypt, as reference key pollen from the Wadi El-Natrun area for palynologists, botanists, taxonomists, and workers in other, related, sciences.     

A reconstruction of the history of a Holocene sand dune on Great Barrier Island, northern New Zealand, using pollen and phytolith analyses

Aim   To reconstruct the history of a Holocene sand dune using pollen and phytolith analyses, and to identify the strengths, weaknesses and compatibility of these two methods in the interpretation of Quaternary coastal environments.
Location  Great Barrier Island, northern New Zealand.
Methods  Pollen and phytolith analyses were carried out on a sequence through a Holocene sand dune containing a palaeosol.
Results  Phytoliths were present throughout the sequence. Grass phytoliths increased at the expense of tree phytoliths following fire disturbance. Pollen (and spores) was preserved only in the palaeosol part of the profile. Pteridium fern spores increased at the expense of tall tree pollen following the fire disturbance.
Main conclusions  Lack of phytolith production by many species and problems of taxonomic specificity in many others restricts the usefulness of phytolith analysis to defining only broad vegetation types. In New Zealand, gymnosperms are invisible in the phytolith record and ferns are extremely under-represented. In contrast, pollen analysis usually provides a great deal of information regarding the composition of a particular vegetation type. The loss of microscopic charcoal fragments during the phytolith extraction process is a disadvantage in the reconstruction of environments where fires have occurred. The greater durability of phytoliths compared with pollen means that phytoliths may be found in sediments where pollen has not been preserved. The phytolith record may also provide evidence of wetter environments that are not apparent in the pollen record. Unlike grass pollen, which is widely dispersed and therefore blurs the spatial record, the presence of grass phytoliths in sediments indicates a local source. The simultaneous application of both methods potentially provides a powerful tool in ecological interpretation and the reconstruction of Quaternary coastal environments.     

Efficient and sensitive identification and quantification of airborne pollen using next‐generation DNA sequencing

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.     

江西安源组植物化石一新属——Jiangxifolium

为了探讨安源煤系的煤层对比,我们对江西丰城县攸洛勘探区内60个钻孔进行了系统的化石采集工作,发现可能属于真蕨类的一个新属——江西叶属(Jiangxifolium gen. nov. ), 化石产于晚三叠世安源组中下部的深灰色粉砂岩中.攸洛勘探区位于丰城县南约28km,区内安源煤系总厚>850m,煤系地层根据岩性从下往上分为5段,现将地层和化石产出层位自上而下介绍如下:     

The Belgian Pollen Phone Service: Immediate and direct information to hay fever sufferers

The Belgian Pollen Phone Service gives continuous information about the pollen content of the air. A comparison of the number of incoming phone calls with the pollen content of the air revealed a surprisingly good correlation. This article underlines the success of this service. It confirms the high susceptibility of hay fever sufferers at the beginning of the season. It also highlights that pollinosis is not always limited to birch and grass pollen allergy and it demonstrates the necessity for the continuous determination of the pollen content of the air. Allergies to mugwort pollen seem to be less important. The Pollen Phone Service is a prompt way to provide allergic subjects with recent pollen information.     

The Belgian Pollen Phone Service: immediate and direct information to hay fever sufferers

The Belgian Pollen Phone Service gives continuous information about the pollen content of the air. A comparison of the number of incoming phone calls with the pollen content of the air revealed a surprisingly good correlation. This article underlines the success of this service. It confirms the high susceptibility of hay fever sufferers at the beginning of the season. It also highlights that pollinosis is not always limited to birch and grass pollen allergy and it demonstrates the necessity for the continuous determination of the pollen content of the air. Allergies to mugwort pollen seem to be less important. The Pollen Phone Service is a prompt way to provide allergic subjects with recent pollen information.     

The Effects of Air Pollution on Structures, Proteins and Allergenicity of Pollen Grains

The prevalence of allergic disease has increased world wide during the last decades. Pollen allergy is the most typical form of allergic disease. The increase in its frequency during recent years is the most evident. Environmental factors play an important role in the problem of pollen allergy in large cities. The aim of this research is determination of allergenicity of Canna pollen in polluted and non-polluted conditions, detection of their allergenic proteins and also elucidation of some microscopic effects of air pollutants on pollen structure and proteins. Mature and immature pollen grains of Canna indica were collected from polluted and non-polluted areas. Pollen grains were studied by scanning electron microscopy. Mice were sensitized by injection of pollen extract and an adjuvant for five times. Allergy potency of different pollen extracts were compared by means of skin test, blood eosinophills number and IgE levels in sensitized and treated animals. Pollen proteins were studied by SDS-PGE and allergenic proteins were detected by immunoblotting techniques. Scanning electron microscope study of the pollen grains showed that in polluted areas, air born particles accumulated on the surface of pollen and changed both pollen's shape and pollen's tectum. Also many vesicles were released out of polluted pollen and the pollen material agglomerated on the surface of pollen. SDS-PAGE showed that different proteins exist in mature and immature pollen. In pollen collected from polluted area, some of protein bands between 22 and 45 kDa were disappeared . Also in all polluted pollen grains, protein content of pollen decreased in response to air pollution causing the release of pollen proteins. According to our experiments and regarding induction of allergic symptoms, the polluted pollen is more effective than non-polluted one, and mature pollen has more allergy potency than immature one.     

Pollen as the link between floral phenotype and fitness

Pollen plays a key role in plant reproductive biology. Despite the long history of research on pollen and pollination, recent advances in pollen-tracking methods and statistical approaches to linking plant phenotype, pollination performance, and reproductive fitness yield a steady flow of exciting new insights. In this introduction to the Special Issue “Pollen as the Link Between Phenotype and Fitness,” we start by describing a general conceptual model linking functional classes of floral phenotypic traits to pollination-related performance metrics and reproductive fitness. We use this model as a framework for synthesizing the relevant literature, highlighting the studies included in the Special Issue, and identifying gaps in our understanding and opportunities for further development of the field. The papers that follow in this Special Issue provide new insights into the relationships between pollen production, presentation, flower morphology, and pollination performance (e.g., pollen deposition onto stigmas), the role of pollinators in pollen transfer, and the consequences of heterospecific pollen deposition. Several of the studies demonstrate exciting experimental and analytical approaches that should pave the way for continued work addressing the intriguing role of pollen in linking plant phenotypes to reproductive fitness.     

Multivariate statistical and other approaches for the separation of cereal from wild Poaceae pollen using a large Holocene dataset

The separation of the pollen of wild Poaceae species from that of domesticated cereal crops is of considerable importance to palynologists studying Holocene vegetational and agricultural change. Studies of the characteristics of modern pollen populations indicate that it may be possible to distinguish cereal pollen from that of many (but not all) undomesticated Poaceae species, though there are few detailed investigations into the applicability of such studies to palaeoecological samples. This paper assesses the reliability of available keys for identifying sub-fossil grass pollen using a large Holocene dataset obtained from a series of well-dated profiles from lowland Yorkshire, England. Pollen within the dataset is classified using the keys of Andersen (Danmarks Geol Undersøgelse, Arbog, 1978, 69–92, 1979) and Küster (1988), and the resulting identifications are compared. The possibilities of combining the two approaches and employing the multivariate statistical techniques of principal component and discriminant analysis to achieve greater confidence of identification are then investigated. Finally, the findings of the above analyses are used to discuss the interpretation of incidences of large Poaceae pollen (i.e. >37 m grain diameter as measured in silicone oil) within the palynological record, particularly during prehistory. The outcomes of this study will be of relevance to other investigations in which careful identification of large grass pollen is desirable, but where preservation or other factors prohibit accurate or confident identification of pollen surface pattern.     

中国现代花粉数据集

孢粉是重建古植被、古气候的重要基础数据。孢粉数据库对研究样点至区域和全球尺度上的古环境演变规律、古气候变化特征反演和古生物地球化学循环模拟等具有重要意义。该文收集整理了中国1960-2020年间发表和部分未发表的现代花粉数据记录, 包括样品编号、采样位置、采样地经纬度和海拔高度、样品类型、数据来源、数据类型、周边植被信息、参考文献、花粉类群及其含量等信息; 并对数据进行筛选和标准化等处理, 由此整合为中国现代花粉数据集。该数据集由4 497个现代花粉采样点的数据信息组成, 包括660个来自中国第四纪孢粉数据库数据, 1 763个前期整理发表的数据和2 074个近期收集的数据, 涵盖772个花粉类群。样品类型以土壤表层样品(3 332个)为主, 苔藓样品以及湖泊、海洋表层样品等为辅, 广泛分布于全国不同地理区域和植被类型中, 其中以温带荒漠区域(24.91%)和亚热带常绿阔叶林区域(24.02%)最丰富, 其次为温带草原区域(16.14%)和青藏高原高寒植被区域(15.83%)。数据按照来源可分为原始数据(58%)和数值化数据(42%); 按照数据类型可分为原始统计粒数的样点(59%)和以花粉百分比表达的样点(41%)。半个多世纪以来, 科研人员开展了大量的表层现代花粉取样和研究。本数据集虽然仅获取部分记录, 但样点覆盖了我国绝大多数地区, 可有效地用于古植被与古气候重建的现代孢粉与现代植被校验, 并将为中国孢粉数据库的建立与更深入的孢粉研究提供数据支撑。     

Pollen in packrat middens

Fossil packrat middens are used to reconstruct late Quaternary environments in the arid Western U.S.A. Airborne pollen is contributed to middens both directly from the air, and through adherence to plant macrofossils. I examined the filtration of atmospheric pollen by Larrea tridentata leaves (resinous, with sparse recumbent hairs), Cercidium microphyllum twigs (glabrous with recumbent hairs) and Sphaeralcea ambigua leaves (covered with stellate hairs) and evaluated the potential biases of scavenged pollen on the interpretation of pollen records from middens. Pollen grains collected from the surfaces of the plants were most numerous during the spring when (airborne) pollen concentrations were high. Of the species investigated, the Sphaeralcea leaves filtered the greatest number of spring pollen grains from the air (3419 grains cm^?2); captured pollen was very low during other seasons. Sticky Larrea leaves continuously captured airborne pollen ( = 246 grains cm^?2). Pollen captured by smooth Cercidium was consistently low ( = 31 grains cm^?2). Only the spring pollen was filtered in sufficient numbers to obtain minimum pollen counts of 200 grains by all 3 taxa. The plants frequently captured greater proportions of their own pollen. Pollen content of packrat middens will reflect the season of plant macrofossil collection and the species composition of the plants incorporated.     

第四纪花粉的无酸碱分析法

第四纪花粉无酸碱分析方法,是从第四纪沉积物中提取花粉的一种行之有效的方法。该流程简单,易于操作,已被大量分析实验证实,与常规的酸碱分析法相比具有不使用酸碱、流程短、花粉破坏少、成本低、污染少等特点。是目前高精度、高分辨第四纪花粉分析的有力工具。     

燕山南部花粉散布特征

燕山南部花９粉用布特性研究表明,空气中的花粉反映的是植物花期的季节性变化,表 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。     

A method to control the spread of allergenic pollen in archaeological and highly frequented areas

Monuments and archaeological areas are oftencolonized by infesting plants, many of whichproduce allergenic pollen that can causeallergic symptoms in sensitive subjects. Pollen monitoring was carried out by a portablevolumetric spore trap in some Romanarchaeological areas and in two small cities inLatium (Central Italy), before and after achemical treatment to eradicate infestingplants of Parietaria spp. to control thequality of the air. Results indicate that the herbicide treatmentreduced the presence of Parietaria plantsand their pollen concentration in the air inthe sites which were the subject of this study.     

Ragweed and mugwort pollen in Szczecin, Poland

Ragweed (genus Ambrosia) and mugwort (Artemisia vulgaris) pollen grains are known to be very potent aeroallergens, often noted to enter into cross reactions. The aim of the study was to analyse ragweed and mugwort pollen release in Szczecin (western Poland) during the period 2000–2003. Measurements were performed by the volumetric and gravimetric method. Pollen seasons were defined as the periods of 90% of the total catch. Of the 4 years studied, the lowest concentration of ragweed pollen was observed in 2000. In 2000, the annual ragweed pollen count was very high, threefold higher than in 2001. There was a high Ambrosia pollen count in 2003, with the highest daily value of 84 grains/m³. The mugwort pollen season started in the third 10-day period of July and lasted to the end of August in all of the years studied. Analysis of pollen deposition from different Szczecin city’s districts showed that the highest exposure to ragweed pollen allergens occurred in the Majowe district, which is related to the presence of numerous plants of Ambrosia in that district. The mugwort pollen deposition was more abundant in the Żelechowa district, which is an area with villas and gardens. Statistically significant correlations were found between the ragweed pollen count in the air and the maximum wind speed, air temperature and relative humidity and between the mugwort pollen count in the air and air temperature and relative humidity.