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1

Larsson, Kent, Sofie Lindström, and Dorothy Guy-Ohlson. "An Early Permian palynoflora from Milorgfjella, Dronning Maud Land, Antarctica." Antarctic Science 2, no. 4 (December 1990): 331–44. http://dx.doi.org/10.1017/s0954102090000463.

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A preliminary palynological study of Beacon Supergroup sedimentary rocks exposed at Milorgfjella, Dronning Maud Land, has yielded a relatively rich and well preserved palynoflora dominated by spores and pollen grains, but also including acritarchs and green algae. The palynoflora is dominated by the pterophyte spores Punctatisporites gretensis, Punctatisporites parvus, Granulatisporites spp., Microbaculispora tentula Horriditriletes spp. and Verrucosisporites andersonii, and the gymnosperm pollen grains Plicatipollenites spp. and Cannanoropollis spp. Also present are the lycopod spore Jayantisporites pseudozonatus, the praecolpate pollen grain Marsupipollenites striatus and the monocolpate pollen grain Cycadopites cymbatus. The palynoflora indicates freshwater conditions or, at least, a major freshwater influence on the depositional environment. Comparison of the palynoflora with others from Gondwana suggests an Early Permian (Asselian–Sakmarian) age.
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2

Kawahata, Hodaka, Rena Maeda, and Hideaki Ohshima. "Fluctuations in Terrestrial–Marine Environments in the Western Equatorial Pacific during the Late Pleistocene." Quaternary Research 57, no. 1 (January 2002): 71–81. http://dx.doi.org/10.1006/qres.2001.2282.

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AbstractLarge heat storage capacity in the western equatorial Pacific has played an important role in modulating global climate. The fluctuation in pollen and spore abundances, together with organic matter (OM) and lithogenics sedimentation, was investigated to reconstruct terrestrial and marine environmental change around New Guinea during the Late Pleistocene. Although appreciable contribution from Indonesian Maritime Continent was expected, the majority of the pollen and spore grains found in core C4402 was transported from New Guinea. Fern spores accounted for 70% (46–90%) of the total pollens and spores. Positive correlation between lithogenic content and the relative abundance of fern spores suggests that lithogenics could be derived from coastal lowland.The mass accumulation rate (MAR) of pollen and spores varied from 44 to 7,031×10−3 grains cm−2 yr−1 with maxima in oxygen isotope stages (OIS) 2, 3, 4, and around the OIS 4/5 boundary. Less rainfall during glacial times generally enhanced transport of pollen by wind to Site C4402. Their scavenging from the water column was promoted by high activity of the biological pump. Pollen record from core C4402 suggests that lower montane group vegetation was dominant relative to lowland vegetation and upper and mid-montane group during glacial times. Although appreciable contribution by terrestrial OM is expected from high correlation of MAR between organic carbon (OC) and pollen and spores, fairly low COrganic/N ratios and δ13C values (around −20‰) of OM demonstrate that OM in core C4402 is mainly of marine origin.
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3

Katsimpris, Petros, Christos Nikolaidis, Theodora-Eleftheria Deftereou, Dimitrios Balatsouras, Athanasia Printza, Theodoros Iliou, Triantafyllos Alexiadis, et al. "Three-year pollen and fungi calendar in a Mediterranean region of the Northeast Greece." Allergologia et Immunopathologia 50, no. 2 (March 1, 2022): 65–74. http://dx.doi.org/10.15586/aei.v50i2.491.

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Introduction and objectives: Pollen calendars have been proved clinically important in allergic disease management, as differences in airborne allergens exist not only between different countries but also between regions of the same country as well. This study aims to provide new data regarding the atmospheric pollen and fungi content of a Mediterranean region (Western Thrace/North-East Greece) and discuss seasonal trends, differences in pollen grains and fungi spores’ circulation over the years, and correlations with climate parameters. Material and methods: A 7-day continuously running volumetric trap was used to collect circulating pollen grains and fungi spores. Pollen taxa and fungi were characterized by standard protocols and counted as grains /m3 and average total grains and spores. The primary allergenic pollen season was discovered, and their 10-day averages were measured over time. Correlations with temperature, rain, and humidity were assessed by single linear regression analysis. Results: Pollen grains from nine pollen families were identified, including five arboreal, two nonarboreal taxa, and spores from two fungi species. The three most prevalent taxa were Oleaceae, Poaceae, Pinaceae, and Cladosporium in the fungi. Peak pollen concentrations were detected during April and May, with daily averages exceeding 170 grains/m3. Poaceae presented the longest pollen season of 342 days and Oleaceae the shortest, extending to only 110 days, during the 3years. Cladosporium was the fungus with the highest spore concentration (180,129.9 spores) compared with Alternaria (28,026.1 spores). Correlations with meteorological parameters showed variable associations among different taxa, with rainfall and relative humidity being the most significant determinants. Conclusion: In this study, the pollenic and fungal spectrum of a Mediterranean region and information that can be proved clinically significant for the appropriate diagnostic and therapeutic approach of allergic patients was presented.
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4

Śliwińska-Wyrzychowska, Anna, Kazimiera Chłopek, Edyta M. Gola, and Monika Bogdanowicz. "The usefulness of aerobiological methods in monitoring lycopod sporulation." Plant Ecology and Evolution 151, no. 2 (August 22, 2018): 284–89. http://dx.doi.org/10.5091/plecevo.2018.1385.

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Background and aims – The purpose of the study was to determine whether the concentration of lycopod spores present in aeroplankton reflects their release during sporulation and whether it is a good indirect tool to estimate the condition of lycopod populations in Poland.Methods – The study was conducted in Sosnowiec, S Poland. The airborne spores were continuously captured by the volumetric spore trap during a period of eleven years (1998–2008). Plant pollen grains and spores from the trap were macroscopically identified, counted and expressed as daily pollen grain and spore concentrations in 1 m3 of air. Key results – The average monthly sum of captured lycopod spores varied in the analysed period of time from 0.3 to 4.1 spores per year. Their yearly concentration was small in comparison to the ascertained pollen grains and did not exceed 0.5% of all airborne particles captured in a given year. In addition, they showed seasonal fluctuations with the highest concentration of spores usually detected in July. This finding is in accordance with the typical time of lycopod sporulation. In addition, we detected the presence of lycopod spores outside the typical summer sporulation time, i.e. during months of winter and early spring. In our opinion, their presence is related to the phenomenon of lengthened (winter) sporulation of clubmosses.Conclusions – Our results showed only limited transportation of lycopod spores by wind. Therefore, the condition of lycopod populations in Poland can hardly be estimated using aerobiological methods. Nevertheless, the seasonal dynamics of lycopod spore concentration can be recorded by aerobiological methods.
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Luz, Cynthia Fernandes Pinto da, Ortrud Monika Barth, and Cleverson Guisan Silva. "Spatial distribution of palynomorphs in the surface sediments of the Lagoa do Campelo lake, North region of Rio de Janeiro State, Brazil." Acta Botanica Brasilica 19, no. 4 (December 2005): 741–52. http://dx.doi.org/10.1590/s0102-33062005000400009.

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Four samples of the surface sediments of the Lagoa do Campelo lake bottom were collected in a transect of 500 m by 500 m from edge to edge, in a northeast/southwest direction, the dominant wind direction in the region. The analysis of pollen grains, fern spores and algae were used to evaluate their spatial deposition and level of deterioration. In total, 58 types of pollen grains were identified, mainly from herbs as Cyperaceae, Poaceae and Typhaceae. Pollen grains occurred in all the analyzed sediments. The area of highest concentration was the northeast side of the lake. The southwest side showed the highest pollen grain and fern spore degradation and mechanical damage, probably as they were carried across the lake by wind-driven currents, confirming the depositional tendency of damaged palynomorphs in the same direction as the dominant wind. Among the pollen of trees and shrubs, Alchornea, Arecaceae, Cecropia, Celtis, Clethra and Myrtaceae were dominant at more than 1,000 pollen grains per gram of sediment. The quantity of fern spores was practically constant in all samples (± 10% of the total of palynomorphs). The algae Pediastrum tetras (Ehrenberg) Ralfs and Mougeotia occurred in all samples, but Spirogyra only in three of them. The results obtained gave new information about the richness, concentration and distribution of palynomorphs in the lake, representing the local and regional vegetation.
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6

Verma, Divya. "PREVALENCE OF AIRBORNE POLLEN GRAINS AND FUNGAL SPORES IN A CITY OF THAR DESERT, INDIA." Journal of Advanced Scientific Research 13, no. 08 (September 30, 2022): 45–53. http://dx.doi.org/10.55218/jasr.202213808.

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Monitoring of bioaerosols i.e., pollen grains and fungal spores, was undertaken for two consecutive years in a city of Thar Desert- Bikaner, using Gravity Slide Method. A total of 32 different pollen taxa were identified with Annual Pollen Integral (API) of 890 pollen grains per sq. cm in the first year and 906 pollen grains per sq. cm in the second year. The pollen count of non-arboreal plants was much more than that of the arboreal plants. The most prominent annual average pollen percentage was credited to Poaceae (25.91%), followed by Chenopodiaceae/Amaranthaceae (17.57%), Papilionaceae (7.86%) and Cyperaceae (5.95%) among non-arboreal plants: and to Prosopis juliflora (14.84%) amongst arboreal taxa. Two peak seasons were observed in both the years i.e., February to April and August to October for both pollen grains as well as fungal spores. 32 types of airborne fungal spores were reported from the atmosphere of Bikaner during the study. A total number of 6717 fungal spores per sq. cm were counted in the first year and 7117 spores per sq. cm in the second year. The commonest fungal spores encountered were of the species of Cladosporium, followed by Alternaria and Curvularia with annual mean percentage of 24.95%, 23.02% and 11.53 respectively.
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7

Calderón LLosa, Oscar Manuel, Denisse Cevallos Levicek, Germán Ramón, Laura Barrionuevo, Karla Robles, Ivan Tinoco, and Iván Chérrez. "Initial study of trap and identification of environmental pollens and fungi spores in Samborondon, Ecuador." Revista Alergia México 71, no. 1 (April 23, 2024): 52. http://dx.doi.org/10.29262/ram.v71i1.1322.

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Initial study of trap and identification of environmental pollens and fungi spores in Samborondon, Ecuador Introduction: The identification of local aeroallergens in any geographical area is essential for the specific diagnosis and treatment of allergic diseases. Our objective was to identify and registry the most important aeroallergens trapped at the aerobiology station in the city of Samborondon, Ecuador.Material and methods:Pollen grains and fungal spore counts were performed according to the standardized technique with a Hirst-type collection equipment, Burkard spore trap for seven days, following the recommendations of the National Allergy Bureau (NAB) of the American Academy of Allergy Asthma and Immunology (AAAAI). The equipment was installed on the roof of the Universidad de Especialidades Espiritu Santo (UEES), 25 m above ground level, coordinates: 2°07 ́57 ́ ́S 79°52 ́06 ́ ́W, in the city of Samborondon. The sampling period was performed from November 2022 to April 2023.Results:We identified the following pollen families: Poaceae (258 grains/m3), Apocynaceae (Plumeria rubra pc) 214 grains/m3, Lamiaceae (180 grains/m3), Asteraceae - Ambrosía spp.- (60 grains/m3), Chenopodiacea (27 grains/m3), Myrtaceae (17 grains/m3), Pinaceae (11 grains/m3), Betulaceae (7 grains/m3).Also identified fungical spores: Fuzariella spp./Leptosphaeria spp. (1899/m3), Cladosporium spp. (1407/m3), Nigrospora spp. (1183/m3), Dreschlera/Helmintosporum spp. (329/m3), Alternaria spp. (98/m3), Pithomyces spp. (79/m3), Curvularia spp. (48/m3), Stemphylium spp. (46/m3).Conclusions:We reported the first study of aerobiology (capture and identification of environmental pollens and fungi) in the city of Samborondon. The inhabitants of this area are exposed to different aeroallergens with a predominance of Poaceaes pollen and Fuzzariella spp./Leptosphaeria spp. spores. The identified allergens should be part of the usual allergy studies. The results of this first preliminary study should be compared with information from the forthcoming years, which will help to identify variations in the concentration of seasonal aeroallergens, annual fluctuations, and extend the traps to other parts of the city.Key words: aerobiology, allergic rhinitis, allergic conjunctivitis, pollens.
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8

Khandelwal, Asha. "Long term monitoring of air-borne pollen and fungal spores and their allergenic significance." Journal of Palaeosciences 51, no. (1-3) (December 31, 2002): 153–59. http://dx.doi.org/10.54991/jop.2002.1743.

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The qualitative and quantitative analyses of aerospora at Birbal Sahni Institute of Palaeobotany are assessed for the biogenic pollutants of Lucknow atmosphere. The Impaction method was employed for preparing annual pollen and spore calendars over six years (1969-1970, 1970-1971, 1971-1972, 1983-84, 1984-1985, 1985-1986). As many as 61 types of pollen grains and 27 types of fungal spores have been encountered. The maximum numbers of pollen grains were recorded in the year 1985-86 (24383) and minimum in the year 1969-70 (13005), whilst the maximum number of fungal spores encountered were in 1971-72 (22604) and minimum in the year 1969-70 (12771). It has been visualized that long term pollen/spore monitoring at a particular site provides a strong base for the prediction of aeroallergens as a warning towards the allergenic disorders. The well recognised allergenic pollen and spore of Lucknow area include Argemone mexicana, Amaranthus spinosus, Cannabis sativa, Chenopodium album, Prosopis juliflora, Cyperus rotundus, Ricinus communis, Xanthium strumarium and many species of Aspergillus.
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9

Kobzar, V., and K. Osmonbaeva. "Aeroallergens as Indicators of the Anthropogenic Triads." Bulletin of Science and Practice, no. 9 (September 15, 2023): 43–57. http://dx.doi.org/10.33619/2414-2948/94/05.

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The growing interest in the complex issue of climate change, environmental pollution and aeroallergens is reflected in the queries of Internet users in various search engines. Recently, articles have been published on the impact of changes in the traditional land use system on the concentration and species composition of plant pollen and fungal spores. The total effects of the influence of the anthropogenic triad on plant pollen and fungal spores: 1) an increase in the time of the beginning of the growth of plants and fungi and, consequently, the beginning of their production; 2) earlier terms and lengthening of the pollination season; 3) an increase in the concentration and species composition of pollen of allergenic plants and fungal spores in the air of the regions, especially in the urban environment, along vertical zonality in mountainous conditions; 4) modification, deformation, fragmentation of pollen grains; 5) change in allergenic potential: increase in the number of allergens in pollen; 6) transformation of allergens in fungal spores; 7) change in the geospatial distribution of plant pollen and fungal spores, i.e. transportation of whole pollen, its fragments and spores over long distances; 8) emergence in the regions, on a global scale of new species of allergenic plants and phytopathogens; 9) changes in the qualitative and quantitative composition of pollen and aerospores, due to a change in the traditional system of land use, sowing of new cultivated plants and, accordingly, the introduction of new phytopathogens; 10) vegetation on the pollen of bacteria and fungal spores that change the structure of the pollen grain; 11) trigger effect of aeroallergens in the occurrence of allergic diseases in humans; 12) an increase in the number of indeterminate pollen and spore particles in aerobiological studies.
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10

Rathnayake, Chathurika M., Nervana Metwali, Thilina Jayarathne, Josh Kettler, Yuefan Huang, Peter S. Thorne, Patrick T. O'Shaughnessy, and Elizabeth A. Stone. "Influence of rain on the abundance of bioaerosols in fine and coarse particles." Atmospheric Chemistry and Physics 17, no. 3 (February 16, 2017): 2459–75. http://dx.doi.org/10.5194/acp-17-2459-2017.

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Abstract. Assessing the environmental, health, and climate impacts of bioaerosols requires knowledge of their size and abundance. These two properties were assessed through daily measurements of chemical tracers for pollens (sucrose, fructose, and glucose), fungal spores (mannitol and glucans), and Gram-negative bacterial endotoxins in two particulate matter (PM) size modes: fine particles (< 2.5 µm) and coarse particles (2.5–10 µm) as determined by their aerodynamic diameter. Measurements were made during the spring tree pollen season (mid-April to early May) and late summer ragweed season (late August to early September) in the Midwestern US in 2013. Under dry conditions, pollen, and fungal spore tracers were primarily in coarse PM (> 75 %), as expected for particles greater than 2.5 µm. Rainfall on 2 May corresponded to maximum atmospheric pollen tracer levels and a redistribution of pollen tracers to the fine PM fraction (> 80 %). Both changes were attributed to the osmotic rupture of pollen grains that led to the suspension of fine-sized pollen fragments. Fungal spore tracers peaked in concentration following spring rain events and decreased in particle size, but to a lesser extent than pollens. A short, heavy thunderstorm in late summer corresponded to an increase in endotoxin and glucose levels, with a simultaneous shift to smaller particle sizes. Simultaneous increase in bioaerosol levels and decrease in their size have significant implications for population exposures to bioaerosols, particularly during rain events. Chemical mass balance (CMB) source apportionment modeling and regionally specific pollen profiles were used to apportion PM mass to pollens and fungal spores. Springtime pollen contributions to the mass of particles < 10 µm (PM10) ranged from 0.04 to 0.8 µg m−3 (0.2–38 %, averaging 4 %), with maxima occurring on rainy days. Fungal spore contributions to PM10 mass ranged from 0.1 to 1.5 µg m−3 (0.8–17 %, averaging 5 %), with maxima occurring after rain. Overall, this study defines changes to the fine- and coarse-mode distribution of PM, pollens, fungal spores, and endotoxins in response to rain in the Midwestern United States and advances the ability to apportion PM mass to pollens.
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Dąbrowska-Zapart, Katarzyna, and Tadeusz Niedźwiedź. "Height and hourly variations in the concentration of airborne pollen grains and fungal spores in Sosnowiec (Poland)." Alergoprofil 16, no. 1 (February 20, 2020): 21–23. http://dx.doi.org/10.24292/01.ap.161120220.

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The aim of the work was to compare the qualitative and quantitative composition of aeroplankton in Sosnowiec (Poland) at three heights. The research was conducted on July 3rd, 4th and 5th, 2018 with the help of three Burkard spore traps: one stationary and two portable ones. The analyses were carried out at an altitude of 83 m, 15 m and at the ground level. Aerobiological data was recorded every hour and the collected pollen grains and fungal spores were determined later on. The relationships between individual meteorological conditions and different features of the alder pollen season were determined using Spearman’s rank correlation coefficients. The research has shown that the greatest fluctuations in the daily pollen count occurred at the lowest measuring point, i.e. at the ground level. The largest part of the determined palynomorphs were fungal spores, the most numerous of which was Cladosporium, followed by Alternaria, Epicoccum and Botrytis. Statistical analysis showed that the highest concentrations of fungal spores and plant pollen grains were influenced by wind speed, maximum gust of wind and solar radiation.
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12

Kasprzyk, Idalia. "Co-occurrence of airborne allergenic pollen grains and fungal spores in Rzeszów, Poland (2000-2002)." Acta Agrobotanica 61, no. 2 (2012): 65–73. http://dx.doi.org/10.5586/aa.2008.034.

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The co-occurrence of airborne allergenic pollen grains and fungal spores was estimated in Rzeszów in the years 2000-2002. The volumetric method was used in this aerobiological study. Six taxa of pollen grains and five types of fungal spores characterized by strong allergenicity and/or high concentrations in the air were analyzed. The time series of pollen grains and fungal spores were compared using PCA analysis. The periods of the greatest concentrations of tree pollen did not coincide with similar periods for herbaceous plants and fungal spores. From February to mid-March, <i>Alnus</i> pollen dominated in the air. The second period was characterized by <i>Betula</i> pollen. It occurred in April. Herbaceous pollen and fungal spores occurred in the air simultaneously (from mid May to the end of August), creating a risky situation for sensitized people. The periods of the highest concentrations of <i>Epicoccum</i> and <i>Ganoderma</i> fungal spores did not coincide with the same period for the examined plant taxa. In Rzeszów the probability of becoming exposed to very high concentrations of allergenic pollen and fungal spores at the same time was high, especially in July, when the highest concentrations of Poaceae, <i>Alternaria</i> and <i>Cladosporium</i> were noted. The hypersensitivity to only one plant or fungal allergen is rarely encountered. Under the present scenarios of global warming, pollen seasons of many taxa will be longer and sufferers will have year-long symptoms.
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13

Walter, O. J., O. H. Adekanmbi, T. O. Onuminya, and J. D. Olowokudejo. "Evaluation of Pollen Grains and Spores Potential in Revealing Vehicle Travel History on the Ife-Ondo Road, Southwestern Nigeria." Journal of Applied Sciences and Environmental Management 27, no. 8 (September 3, 2023): 1817–23. http://dx.doi.org/10.4314/jasem.v27i8.28.

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This study focuses on the significance of airborne pollen grains and spores as markers for tracking vehicles along specific routes. Using standard methods, the research examined monthly pollen distribution and its correlation with meteorological data. Dust and soot samples were collected monthly from the car air filters of commercial vehicles traveling on the Ife-Ondo road and subjected to palynological analysis for a period of 24 months. The findings revealed a total of 393 pollen grains and 131 spores, representing 40 pollen and 22 spore types from 27 and 17 families, respectively. Notable markers among these include Hagenia abyssinica, Podocarpus milanjianus, Theobroma cacao, Cannabis sativa, and Myrianthus arboreus, among others. These markers serve as crucial identifiers for vehicle-related investigations. The study revealed a statistically significant positive correlation between monthly total airborne pollen concentrations and relative humidity, rainfall, and wind speed. In a practical context, the study has created a valuable dataset and monthly atlas of pollen and spore types. This resource can be instrumental for security agencies in their efforts to investigate vehicle-related crimes and monitor vehicular movements along the Ife-Ondo road.
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Jankovská, Vlasta. "Pollen- and Non Pollen Palynomorphs- Analyses from Svalbard." Czech Polar Reports 7, no. 2 (June 1, 2017): 123–32. http://dx.doi.org/10.5817/cpr2017-2-12.

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We analysed fifteen samples of a shallow profile “Sverrefjellet Volcano “, located in the NW part of Svalbard – Bockfjord region (see Fig.1). Frequency of pollen grains, spores and NPP (Non Pollen Palynomorphs) was quite low. Only the local taxa (e.g. Salix and Cyperaceae) produced pollen in greater abundance. The pollen spectrum was considerably varied, although pollen grains and spores of most taxa were present in low abundances. This was due to low pollen and spores productivity of the Arctic flora, which propagates mostly in a vegetative way. To obtain as much information from the profile under study as possible, we analysed the non- pollen palynomorphs as well. We succeeded above all in determination of eggs, buccal tubes and claws of the Tardigrada phylum (Jankovská 1991). The determination has been recently verified by specialists in the field, prof. L. Kaczmarek and dr. M. Roszkowska (in Jankovská et al. 2016). The results of the pollen- and NPP analysis are presented in pollen- and NPP diagram, which represents a picture of the species-poor Arctic flora.
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15

Golińska, Barbara. "Changes in the concentration of grass pollen in the atmosphere of Poznań." Acta Agrobotanica 59, no. 1 (2012): 317–24. http://dx.doi.org/10.5586/aa.2006.033.

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The aim of the study was to determine the concentrations of grass pollen during the vegetation season in the atmosphere of Poznań against the background of the content of pollen of other plants and mould fungi. Observations were conducted in 1997. Concentrations of pollen grains and spores of mould fungi in the atmosphere were assessed by the volumetric method. For this purpose, the Burkard apparatus (Seven-Day Recording Volumetric Spore Trap) was set up on the roof of the 8-storey high building of the Maximum College of the Agricultural University in Poznań. The continuous, 24-hour work of the apparatus made possible to monitor concentrations of allergenic pollen throughout the experiment. The tape was glued to a microscopic glass and evaluated under the light microscope. The number of pollen grains and mould spores on individual sections (2 mm per hour) of the tape allowed determining their concentration per 1 m<sup>3</sup> of air. Microscopic evaluation was conducted every 24 hours, collecting analytical material from the trap at 10 a.m. in which pollen and spores were determined. From among many wind pollinated taksons of plants, species from the grass family - because of their long period of pollination and clinical significance - play an important role in the structure of allergenic pollen in the atmosphere of Poznań. The highest concentration of grass pollen was recorded during the period from the end of May to the end of the first decade of July. From then on, the concentration of grass pollen in the air dropped rapidly and remained on a low level, not exceeding 7.5 pollen grains calculated per 1 m<sup>3</sup> air per 24 hours. The higher concentration of grass pollen was recorded on June 29<sup>th</sup> - 360.4 grains · m<sup>-3</sup>. In terms of 24-hour period, the highest concentrations of the pollen grains in the air on a day without rain occurred between 9 and 11 a.m., whereas the lowest - at night.
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16

Guarín, Fernando Alzate, Mario Alberto Quijano Abril, Astrid Alvarez, and Ramiro Fonnegra. "Atmospheric pollen and spore content in the urban area of the city of Medellin, Colombia." Hoehnea 42, no. 1 (March 2015): 9–19. http://dx.doi.org/10.1590/2236-8906-52/2013.

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The atmosphere of the urban area of the city of Medellin, Colombia was monitored with the objective of identifying airborne pollen and spores throughout a whole year. Sampling was performed between February 2010 and March 2011, coinciding with the La Niña climate phenomenon, which is characterized by a considerable increase in precipitation. Samples of airborne spores and pollen were obtained from a suction Hirst-type volumetric sampler. A total of 62 pollen and spores types were recorded during sampling, of which 30 were angiosperms, two were gymnosperms, 10 were monilophytes, and 20 were fungi. The families displaying the highest pollen counts were Oleaceae, Poaceae, Cyperaceae, Chenopodiaceae and Polypodiaceae. We recorded an inverse relationship among precipitation and the quantity and diversity of pollen grains and fern spores. The angiosperm and gymnosperm taxa showed the greatest recorded grains throughout the sampling year with respect to the species mentioned herewith, which have been reported as allergenic in various aerobiological studies.
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17

Behling, Hermann, and Raquel R. B. Negrelle. "Vegetation and pollen rain relationship from the tropical Atlantic rain forest in Southern Brazil." Brazilian Archives of Biology and Technology 49, no. 4 (July 2006): 631–42. http://dx.doi.org/10.1590/s1516-89132006000500013.

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The relationship between the southern Brazilian tropical Atlantic lowland rain forest and modern pollen rain was studied by pollen traps. The study was carried out on a one hectare plot undisturbed rain forest of the reserve Volta Velha and two secondary forests, ± 50 and 7 years old. About 248 identified tree, shrub and herb species (excluding epiphytes) of 50 families were represented by 126 different pollen and spore types (including non-local taxa). The calculated average influx of pollen rain from the native Atlantic rain forest was 12465 pollen grains per cm² and year. The influx from the ± 50 years old and from the 7 years old secondary forest was relatively low (4112 and 3667 grains per cm² and year, respectively) compared to the undisturbed rain forest. The occurrence of pollen grains of herbs and fern spores were significantly higher in the secondary forests than in the undisturbed rain forest.
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18

Nair, P. K. K. "Pollen spore morphology and plant evolution." Journal of Palaeosciences 45 (December 31, 1996): 130–33. http://dx.doi.org/10.54991/jop.1996.1227.

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Spores and pollen grains both are resistant to environmental stress and diagnostic by virtue of the unique exine characteristics, by which it has emerged as a reliable tool in evolutionary biology, both of fossils and present day plants, at various taxa levels. “Sporae Dispersae” being the only morphological material reflecting continuity of evolutionary lineage through geological time, there is new scope for its application in fixing stratigraphic successions and phyletic origins. The triphyletic theory of the origin and evolution of angiosperms has been explained to demonstrate the value of pollen grains and spores in phylogenetic taxonomy, and further, the emerging areas of application of the principles of morphological evolution of pollen grains have been indicated.
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19

IANOVICI, Nicoleta, Cristina MARIA, Mădălina Nicoleta RĂDUŢOIU, Anca HANIŞ, and Dorina TUDORICĂ. "Variation in Airborne Fungal Spore Concentrations in Four Different Microclimate Regions in Romania." Notulae Botanicae Horti Agrobotanici Cluj-Napoca 41, no. 2 (December 6, 2013): 450. http://dx.doi.org/10.15835/nbha4129032.

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Airborne fungal counts and types were examined in four regions from Romania. The aim of our study was to determine the concentrations of Alternaria, Cladosporium, Drechslera-type, Epicoccum and Nigrospora atmospheric fungal spores in urban areas: Braşov, Bucharest, Cluj-Napoca and Timişoara. Other objective of this study was to examine the relationships between atmospheric fungal spores and pollen. Few studies have confirmed the high frequency and concentrations for some of these spore types in Romania. The sampling sites differed in habitat characteristics, such as vegetation and microclimate. Airborne spores’ sampling was carried out using the Lanzoni volumetric sampler and during August 2008. The totals of airborne spores recorded in this study show a considerable variation. Cladosporium and Alternaria have been identified as the most abundant and frequent fungal aeroallergens in Timişoara and Bucharest. Drechslera-type, Epicoccum, and Nigrospora had very low values of spore count in all sites. Observations show that seven types of pollen appear regularly and few of these are in great abundance. Fungi are present in the air in concentrations considerably in excess of that of pollen grains. Ambrosia artemisiifolia is the most important pollen allergen in all of the sampled areas discussed here, especially in western country (Timişoara).
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Santos, R. P., L. M. Rebelo, E. F. Costa, A. A. X. Santiago, V. N. Freire, J. A. K. Freire, G. A. Farias, T. M. Oliveira, G. A. Bezerra, and B. S. Cavada. "Sporopollenin Nanostructure of Ilex paraguariensis A.St.Hil Pollen Grains." Microscopy and Microanalysis 11, S03 (December 2005): 78–81. http://dx.doi.org/10.1017/s1431927605050932.

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Pollens appear like a fine to coarse powder that is liberated by the microsporangia of Gimnosperms and Angiosperms. The pollen grain wall, the sporoderm, envelopes the microgametophytes (male gametophytes), which produce the male gametes of seed plants. Pollen grains are interesting from the material science point of view since the native polymer, the sporopollenin, found in the sporoderm outer layer (exine), is one of the toughest known materials which is degraded by oxidation but is resistant to reduction. This property permits the sporopollenin persistence as an unaltered polymer in sediments of great age, e.g the Ordovician period, 400 million years ago. Sporopollenin is a mixture of fatty acids, phenyl-derivatives as p-coumaric acid, and carotenes [1]. Its nanostructure is not yet completed revealed. Therefore, more studies must be performed. A number of models have been proposed for the sporopollenin nanostructure of spores and pollen grains [2]. Rowley et al. [3-4] interpret exine structure as being formed by helical subunits, based on transmission and scanning electron microscope (TEM and SEM) studies. The atomic force microscopy (AFM) is the ideal method to study the sporopollenin nanostructure [5] since the arrangement of components is not visualized easily through other microscope techniques (e.g. TEM and SEM). In the present work, we used AFM to study the sporopollenin nanostructure of the Ilex paraguariensis A.St.Hil. exine, an Angiosperm (Aquifoliaceae).
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Gazi, Md Yousuf, Subrota Kumar Saha, SM Mainul Kabir, and Md Badrul Imam. "Sedimentological and Palynological Approach for Determining the Depositional Environment of the Outcropping Surma Group Mudrocks in the Sitakund Anticline, Chittagong-Tripura Fold Belt, Bangladesh." Dhaka University Journal of Science 66, no. 1 (January 31, 2018): 37–42. http://dx.doi.org/10.3329/dujs.v66i1.54542.

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Sitakund anticlinal structure exposes about 1.5 km of Surma group sediments and has been chosen for a comprehensive study of the mudrocks depositional environment based on sedimentological and palynological evidences. Five mudrock facies have been identified in this region. They are Mudstone Dominated, Sand/Silt Streaked Shale, Fissile Shale, Laminated Shale and Lenticular Bedded Shale. The palynological assemblages from these samples have been analyzed qualitatively, and a variety of pollen, spores, algae and fungi identified. The pollen and spores have been attributed to parent plants located at the immediate and more regional surrounding areas during the deposition of these sediments. Palynological assemblages incorporates ample of Palmae grains such as spores in the Palmipollenites and Proxaperites and predominance of pteridophytic spores. The occurrences and abundances of these pollens indicate that the deposition of the Surma mudrocks took place at the proximity of the shore level. Coastal fluvial environment is also triumphed after the previous depositional event which is apparent by the occurrence of palynomorphs of pteridophytes, angiosperms and algal origin. Dhaka Univ. J. Sci. 66(1): 37-42, 2018 (January)
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Barreto, Cintia F., Cynthia F. P. da Luz, José A. Baptista-Neto, Claudia G. Vilela, and Ortrud M. Barth. "Palynological analysis of a sediment core obtained in Guanabara Bay, Rio de Janeiro, Brazil." Anais da Academia Brasileira de Ciências 79, no. 2 (June 2007): 223–34. http://dx.doi.org/10.1590/s0001-37652007000200005.

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The sediment of a core collected about 2 km north of Paquetá Island, Guanabara Bay, was submitted to pollen analysis, in order to recognize the dynamics of the regional vegetation, and the anthropic influence. Radiocarbon dating of a sample next to the bottom of the core indicates an age of 4.210 ± 40 14C yrs B.P (calibrated age). It was possible to establish four palynological zones. Starting at the bottom of the core, a decrease in palynomorph concentration, the presence of degraded pollen grains and spores, and the predominance of ombrophilous forest pollen grains were observed in the basal portion of Zone I. These data may indicate the presence of an exuberant Atlantic Forest, dominated by a marine regressive event. The concentration of well-preserved palynomorphs increased in Zone II, with the predominance of the ombrophilous forest vegetation also, and an expressive increase of hygrophytes, indicating more humid environmental conditions. Palynomorph concentration decreased again toward the top of Zone III, and the field vegetation was predominant. In the upper Zone IV occurred a strong decrease in pollen and spore concentration, with predominance of field vegetation also, and the appearance of exotic pollen grains, showing the anthropic influence at this time.
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Di Menno di Bucchianico, Alessandro, Raffaela Gaddi, Maria Antonia Brighetti, Denise De Franco, Annarosa Miraglia, and Alessandro Travaglini. "Status and Trend of the Main Allergenic Pollen Grains and Alternaria Spores in the City of Rome (2003–2019)." Sustainability 15, no. 7 (April 3, 2023): 6150. http://dx.doi.org/10.3390/su15076150.

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Today a large part of the European population is exposed to levels of air pollution exceeding the standards recommended by the World Health Organization. Moreover, air pollution and the seasonal emission of allergenic pollen are progressively affecting human health and can cause severe allergic reactions, particularly when air pollution combines with pollen allergen peaks. Unlike atmospheric pollutants of anthropogenic origin, pollen sources have a pulsating trend that leads to high values in the flowering period and values close to, or equal to, zero in the rest of the year. This aspect makes essential the definition of data coverage standards for the main allergenic taxa. For air quality assessment detailed classification criteria for monitoring stations are defined by international standards, not the same from the European Standards for the Sampling and analysis of airborne pollen grains and fungal spores. This paper describes the status and the air concentration trends of the main allergenic pollen and the Alternaria spore measured in Rome from 2003 to 2019 by the Aerobiological Monitoring Center of Tor Vergata (Rome) and calculated by the Seasonal Kendall test with the open-source OpenAir R package. The analysis was carried out on the daily concentrations of the most widespread allergenic taxa in Italy: Asteraceae, Betulaceae, Corylaceae, Cupressaceae/Taxaceae, Poaceae, Oleaceae, Urticaceae and the Alternaria spores.
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Haratym, Weronika, Elżbieta Weryszko-Chmielewska, and Marta Dmitruk. "An analysis of the content of pteridophyta spores in aeroplankton of Lublin (2013–2014)." Acta Agrobotanica 67, no. 3 (2014): 21–28. http://dx.doi.org/10.5586/aa.2014.041.

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Similarly to fungal spores and pollen grains, pteridophytic spores can cause allergies in humans. Pteridophyta spore concentrations in the air of Lublin, under the conditions of central-eastern Poland, were first studied over the period 2013–2014. The volumetric method was used in this study. The research showed that that spores of ferns belonging to the following genera: <em>Asplenium, Athyrium, Blechnum, Botrychium, Cystopteris, Dryopteris, Matteuccia, Osmunda, Polypodium</em> and <em>Pteridium</em>, occur in aeroplankton. Spores were recorded in low concentrations and they occurred in a dispersed pattern during the season. They were found to be absent on some days. Among the above-mentioned genera, <em>Dryopteris</em> and <em>Athyrium </em>showed the highest content of spores in aerosol. In both years of the study (2013 and 2014), similar annual spore counts were recorded, respectively 69 and 63. The most spores were identified in August.
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Chandra, Anil, and Madhav Kumar. "Palynology of the Late Tertiary sediments (DSDP Site 218) in the Bengal Fan, Indian Ocean." Journal of Palaeosciences 46, no. 3 (December 31, 1997): 51–69. http://dx.doi.org/10.54991/jop.1997.1348.

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Palynological assemblage from DSDP Site 218 in the Bengal Fan comprises spores, pollen, fungal fruiting bodies and dinoflagellate cysts. The palynofloral composition has minor variation in core no. 27 to 12. The microthyriaceous fungal remains show comparatively higher frequency than other fungal entities. The gymnosperms are represented mostly by the pollen grains of Podocarpaceae and Araucariaceae. Angiosperm pollen are sparsely observed in the assemblage. The pteridophytic spores occur mostly in the bottom and middle cores (core nos. 27-26 and 23-20). Recycled Cretaceous spores have also been found in most of the core samples. This palynoassemblage from Site 218 is comparable to that of the Miocene sediments of northeast India. The environmental relationship of the taxa shows similarity with the modem plants inhabited in the subtropical climate.
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Tiwari, R. S., and Ram-Awatar. "Sporae-dispersae and correlation of Gondwana sediments in Johilla coalfield, Son Valley Graben, Madhya Pradesh." Journal of Palaeosciences 37, no. (1-3) (December 31, 1988): 94–114. http://dx.doi.org/10.54991/jop.1988.1604.

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The dispersed spores and pollen grains preserved in the sediments exposed along Johilla River Section, Ganjra Nala Section and in three bore-cores, viz., JHL-23, JHL-24, JHL-25, in Johilla Coalfield have been described. The rich miofloral assemblage consists of 58 genera and 126 species, out of which seven species are new on the basis of their morphological characters. These are - Callumispora paliensls, C. saksenae, Osmundacidites baculatus, Dentatispora mammoida, D. reticulata, Gondisporites reticulatus and Lunatisporites paliensis. On the basis of the composition of spores and pollen grains, it has been concluded that the South Rewa Gondwana Basin shows a broader relationship with equivalent strata in other basins of India. In general, the monosaccate pollen has a better representation in the Talchir as well as Barakar sediments which is suggestive of relatively cooler conditions than those in Damodar Valley. Six palynological zones have been identified on the basis of quantitative analysis.
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Balme, Basil E. "Fossil in situ spores and pollen grains: an annotated catalogue." Review of Palaeobotany and Palynology 87, no. 2-4 (August 1995): 81–323. http://dx.doi.org/10.1016/0034-6667(95)93235-x.

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Gedl, Przemysław, and Jadwiga Ziaja. "Palynofacies from Bathonian (Middle Jurassic) ore-bearing clays at Gnaszyn, Kraków-Silesia Homocline, Poland, with special emphasis on sporomorph eco-groups." Acta Geologica Polonica 62, no. 3 (December 28, 2012): 325–49. http://dx.doi.org/10.2478/v10263-012-0018-7.

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ABSTRACT Gedl, P. and Ziaja, J. 2012. Palynofacies from Bathonian (Middle Jurassic) ore-bearing clays at Gnaszyn, Kraków- Silesia Homocline, Poland, with special emphasis on sporomorph eco-groups. Acta Geologica Polonica, 62(3), 325-349. Warszawa. The palynological organic matter of dark clays from Bathonian ore-bearing clays exposed at Gnaszyn (Częstochowa, Kraków-Silesia Homocline, Poland) consists of high proportions of land-derived particles; aquatic elements (mainly dinoflagellate cysts) are comparatively rare. Terrestrial particles include black opaque phytoclasts, dark brown phytoclasts, cuticle remains and subordinate sporomorphs. The latter are represented by eighty-four taxa of spores and pollen grains. They represent various groups of plants, including Bryophyta, Sphenophyta, Lycophyta, Pteridophyta, Pteridospermophyta, Cycadophyta or Ginkgophyta and Coniferophyta. The most frequent sporomorphs in almost all samples from Gnaszyn are Callialasporites (Araucariaceae), Cerebropollenites and Perinopolleniteselatoides (Taxodiaceae) pollen grains, fern spores with triradiate tetrad mark, bisaccate pollen grains belonging to conifers (Pinaceae or Podocarpaceae) and also to Pteridospermophyta. Quantitative analysis of the palynofacies shows fluctuations of particular element ratios, which correlate with lithology. Clay intervals that contain siderite concretion levels yielded lower amounts of cuticles in relation to sporomorphs (mainly pollen grains) and dinoflagellate cysts. Intervals of monotonous clays and silts are characterized by a higher ratio of cuticles in relation to other elements, especially dinoflagellate cysts. Also, quantitative analysis of the sporomorphs shows changes in frequency of the representatives of various plant communities, which coexisted during the Jurassic: Upland, Lowland, River, Pioneer, Coastal and Tidally-influenced. These changes might have reflected sealevel fluctuations, which affected vegetation growing on adjacent land. However, the dominance of Callialasporites pollen grains, which belong to the Coastal community, indicates that the Gnaszyn assemblage was mainly influenced by the seashore vegetation. The high frequency of Araucariaceae pollen grains and the presence of ferns representing the Osmundaceae, Cyatheaceae, Dicksoniaceae, Schizeaceae, Gleicheniaceae and Matoniaceae indicate a warm climate without large seasonal amplitudes during the deposition of the Gnaszyn succession.
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Agnihotri, Deepa, S. S. K. Pillai, Neha Aggarwal, Rajni Tewari, Andre Jasper, and Dieter Uhl. "Palynomorphs from the Barakar Formation of Dhanpuri Open Cast Mine, Sohagpur Coalfield, Madhya Pradesh, India." Journal of Palaeosciences 67, no. (1-2) (December 31, 2018): 171–84. http://dx.doi.org/10.54991/jop.2018.56.

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Well preserved palynomorphs from the Barakar Formation of Dhanpuri Open Cast Mine, Sohagpur Coalfield, Shahdol District, Madhya Pradesh are reported for the first time. The palynomorphs include megaspores and spores/pollen grains. Dispersed megaspores are represented by 6 genera and 13 species comprising Banksisporites indicus, B. utkalensis, Banksisporites sp., Barakarella shuklae, Barakarella sp., Biharisporites sp. Bokarosporites rotundus, Bokarosporites sp., Jhariatriletes baculosus, Jhariatriletes sp., Talchirella flavata, T. trivedii and Talchirella sp. The microspore assemblage shows dominance of monosaccate pollen grains namely Parasaccites obscures, P. korbaensis and Plicatipollenites indicus, along with sub–dominance of non–striate bisaccate taxa Scheuringipollenites barakarensis and S. maximus. Other palynomorphs include trilete Callumispora barakarensis, striate bisaccate pollen grains Faunipollenites sp. and Striatopodocarpites multistriatus, non striate bisaccate genera Ibisporites diplosaccus and Platysaccus ovatus, along with Tiwariasporis gondwanensis and Vitreisporites sp.
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Sandesh Thaware, Jayshree. "ELECTRON MICROSCOPIC STUDIES OF SOME ANTICANCER PLANTS POLLEN GRAINS." International Journal of Advanced Research 9, no. 10 (October 31, 2021): 1386–93. http://dx.doi.org/10.21474/ijar01/13695.

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Pollen is appropriately referred by some as Golden dust extremely valuable on account of their tremendous applications in science, industries and public health. No other plant part even though extremely tiny in size is packed with so much information and power. Similar to other plant parts, pollen characters are so varied that the classification system of plants can be built up entirely on the basis of pollen morphology.Palynology is the distinct branch of biology that deals with the dispersed microscopic tiny living and fossil entities including pollen grains, spores, algal and fungal fragments and others. An important aspect of Palynology is the Pollen morphology. The importance of Palynology in taxonomic and phylogenetic consideration of plants is well known. The changes occurring through hybridization and years of cultivation are reflected in pollen morphology. The scope and interest in the study of pollen morphology have widened with the advent of Scanning Electron Microscopy (SEM) and with regards to unipalynous taxa particularly the understanding of finer morphology is of fundamental importance. SEM gives a correct understanding of exine surface as the electron photographs of the surface replica of the exine provides the exact picture of the ornamentation pattern. The variation in the pollen morphological characters helps in the classification of plant taxa and their assessment of their phylogenetic relationship. In the present investigation, the pollen morphological studies were carried out of some ethnomedicinal plants like Catharanthus roseus, Allamanda cathartica, Datura metel, Brassica juncea, Raphanus sativus and Cleome viscosa pollen grains by Scanning electron microscopy. All that they possess anticancer characteristics in common.
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Chan-Yeung, Moira, and Santiago Quirce. "Aeroallergens and Asthma." Canadian Respiratory Journal 1, no. 4 (1994): 248–56. http://dx.doi.org/10.1155/1994/780479.

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The main aeroallergens in both the indoor and outdoor environment that have been implicated in the pathogenesis of allergic asthma are reviewed. Pollen and fungal spores are important outdoor aeroallergens that cause sensitization in atopic subjects, leading to rhinitis and asthma in a proportion of the sensitized subjects. Each pollen type displays a particular seasonal periodicity: tree pollen are prevalent in the late winter and spring, grass in the spring and summer and weed mainly in the fall. There are regional differences in the type of pollen grains in Canada. Although the pollen grains arc large fragments less than 10 µ can reach the lower airways to cause asthma. Some fungal spores. such asAlternariaandCladosporium, have been implicated in asthma. The full clinical impact of fungi in asthma has yet lo be clarified. With the construction of homes that are tightly scaled to conserve heat and the use or wall to wall carpet. the type and concentration of indoor aeroallergens have become increasingly different from outdoors. House dust mite and pet allergens have now been shown to he important acro:dlergcns that sensitize children in infancy and are risk factors for asthma. Clinicians should recognize the importance of aeroallergens in asthma because avoidance and/or reduc1iun of exposure is an important part of the management besides drug therapy.
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Tripathi, R. P., B. D. Sharma, and K. L. Shrivastava. "Plant microfossils from the lignite deposit (Eocene) of Barsinghsar in Bikaner District, Rajasthan, India." Journal of Palaeosciences 47 (December 31, 1998): 110–15. http://dx.doi.org/10.54991/jop.1998.1278.

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Plant microfossils from the Eocene lignite sample collected from Barsinghsar near Bikaner, Rajasthan have been described in this paper. The plant microfossils include algal filaments and nets, fungal hyphae and spores, bryophytic thalli and capsules (?), pteridophytic cuticles and spores, cuticles of gymnosperms and various kinds of pollen grains, and cuticles and peculiar fructifications (?) of angiosperms. Palaeoecological conditions during sedimentation of Eocene lignite in Rajasthan have also been discussed.
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Bhivgude, S. W. "Curvularia As Bio-pollutant in the Houses of Asthmatic Patients at Ambajogai Dist. Beed (MS)." Plantae Scientia 2, no. 3 (September 15, 2019): 45–47. http://dx.doi.org/10.32439/ps.v2i3.45-47.

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Indoor Curvularia spores are potential sensitizers in human beings, their prevalence is important for diagnosis and environmental management of asthma. Human beings are known to suffer from major allergens such as fungal spores, pollen grains and house dust present in the atmosphere. Inhalation of air borne fungal spores is the main causative factor for respiratory allergic diseases in human beings. Indoor survey of aeromycoflora was performed by using Rotorod air sampler, Petri plate exposure and eosinophil count of asthmatic patient in Ambajogai. The highest concentration of Curvularia spores was recorded in the house of patient. ‘W’ (12.08 %) in the month of September 2000.
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STUKINS, STEPHEN. "IS ABERRANCY A RELIABLE INDICATOR FOR MAJOR PALEOCLIMATIC DISTURBANCE?" PALAIOS 37, no. 5 (May 24, 2022): 145–49. http://dx.doi.org/10.2110/palo.2021.019.

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ABSTRACT Aberrant forms of many different spore and pollen taxa (sporomorphs) are often used to assess timings and extent of environmental stress at major extinction/climate events. However, little is known about the normal level of malformations in these taxa. Malformation can manifest in several different ways, including significant size differences (± from the accepted range for the species), retention of pollen/spores within tetrads, and unusual and inconsistent morphological aberrations. This study analyses one commonly used pollen genus, Classopollis, and its aberrant forms, from the Bajocian of Argentina. Tetrads, including those incorporating malformed/aborted pollen grains, are found to be common, showing that tetrads of Classopollis are not a reliable signal of major environmental disturbance. The results and discussion presented here emphasize why palynological data must be interpreted in context of the depositional dynamics, facies changes and how they affect the assemblages in conjunction with understanding variations in the strategies of individual flora.
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KLEPZIG, MIRIAN CAZZULO. "Significado Peleoecológico de Alguns Palinomorfos Ocorrentes nos Carvões Eopermianos do Rio Grande do Sul, Sul do Brasil." Pesquisas em Geociências 28, no. 1 (June 30, 2001): 81. http://dx.doi.org/10.22456/1807-9806.20169.

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Organic-walled palynomorphs of unknown botanical affinity identified in Early Permian coals from Rio Grande do Sul State, South Brazil, together with spores and pollen grains are analysed in this study. Among the identified taxa are: Tetraporina punctate, Tetraporina horologia, Maculatasporites gondwanensis, Brazilea scissa, Quadrisporites horridus, Quadrisporites lobatus, Pilasporites calculus, Portalites gondwanensis. Besides these palynomorphs, some considerations about Botryococcus braunii, a colonial alga occurring in the associations are presented. The morphological similarity between these microfossils and some algal spores spanning in age from Devonian until Recent permit significant comparisons which improve the knowledge on the spectrum of habitats of these palynomorphs. This study corroborates the idea that the peats, originated in lagoons located in coastal plains, were formed by a biomass composed of spores and pollen grains, plant cuticles, wood remains, fungi and algae, in addition to some forms related to Acritarcha or incertae sedis. Minor marine ingressions would be responsible for the occurrence, in the peat-plant association, of elements related to marine microplankton, like acritarchs, thus confirming the inference of a transitional (barrier/lagoon type) depositional environment for the coals as previously suggested by other authors.
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Pummer, B. G., H. Bauer, J. Bernardi, S. Bleicher, and H. Grothe. "Birch and conifer pollen are efficient atmospheric ice nuclei." Atmospheric Chemistry and Physics Discussions 11, no. 10 (October 5, 2011): 27219–41. http://dx.doi.org/10.5194/acpd-11-27219-2011.

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Abstract. The ice nucleation of bioaerosols (bacteria, pollen, spores, etc.) is a topic of growing interest, since their impact on ice cloud formation and thus on radiative forcing, an important parameter in global climate, is not yet fully understood. Here we show that pollen of different species strongly differ in their ice nucleation behaviour. The average freezing temperatures in laboratory experiments range from 240 K to 255 K. As the most efficient nuclei (silver birch, Scots pine and common juniper pollen) have a distribution area up to the Northern timberline, their ice nucleation activity may be a cryoprotective mechanism. Far more intriguingly, it has turned out that water, which has been in contact with pollen and then been separated from the bodies, nucleates as good as the pollen grains themselves. So the ice nuclei have to be easily-suspendable macromolecules located on the pollen surface. Once extracted, they can be distributed further through the atmosphere than the heavy pollen grains and so augment the impact of pollen on ice cloud formation even in the upper Troposphere. Our experiments lead to the conclusion that pollen ice nuclei, in contrast to bacterial and fungal ice nucleating proteins, are non-proteinaceous compounds.
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Pummer, B. G., H. Bauer, J. Bernardi, S. Bleicher, and H. Grothe. "Suspendable macromolecules are responsible for ice nucleation activity of birch and conifer pollen." Atmospheric Chemistry and Physics 12, no. 5 (March 7, 2012): 2541–50. http://dx.doi.org/10.5194/acp-12-2541-2012.

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Abstract. The ice nucleation of bioaerosols (bacteria, pollen, spores, etc.) is a topic of growing interest, since their impact on ice cloud formation and thus on radiative forcing, an important parameter in global climate, is not yet fully understood. Here we show that pollen of different species strongly differ in their ice nucleation behaviour. The average freezing temperatures in laboratory experiments range from 240 to 255 K. As the most efficient nuclei (silver birch, Scots pine and common juniper pollen) have a distribution area up to the Northern timberline, their ice nucleation activity might be a cryoprotective mechanism. Far more intriguingly, it has turned out that water, which has been in contact with pollen and then been separated from the bodies, nucleates as good as the pollen grains themselves. The ice nuclei have to be easily-suspendable macromolecules located on the pollen. Once extracted, they can be distributed further through the atmosphere than the heavy pollen grains and so presumably augment the impact of pollen on ice cloud formation even in the upper troposphere. Our experiments lead to the conclusion that pollen ice nuclei, in contrast to bacterial and fungal ice nucleating proteins, are non-proteinaceous compounds.
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38

Shu, Ouyang, Deng Xi-Guang, Shen Yan-Bin, Zheng Xiang-Shen, and Liu Xiao-Han. "Late Triassic plant microfossils from Miers Bluff Formation of Livingston Island, South Shetland Islands, Antarctica." Antarctic Science 12, no. 2 (June 2000): 217–28. http://dx.doi.org/10.1017/s0954102000000274.

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A moderately diverse assemblage of plant microfossils has been recovered from the Johnsons Dock Member of the Miers Bluff Formation, Livingston Island, including spores, pollen, acritarchs, wood fragments and cuticles. Containing a total of c. 45 of miospore taxa, the palynoflora is dominated by non-striate bisaccate pollen, but spores of pteridophytes and pollen of gymnosperms are proportionate in diversity. The palynoflora is similar in composition to those indicative of subzones C + D of the Alisporites Zone of Antarctica, and the upper Craterisporites rotundus Zone and the lower Polycingulatisporites crenulatus Zone of Australia as well as the upper Polycingulatisporites crenulatus Zone and Foveosporites moretonensis Zone of New Zealand, suggesting a Late Triassic (possibly Norian–Rhaetian) age. This determination is supported by the sporadic occurrence of Aratrisporites and Classopollis in the palynoflora as well as by the absence of striate bisaccate grains.
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Verma, Poonam, Nivedita Mandal, Mahesh G. Thakkar, M. R. Rao, and Sunil Bajpai. "Palynological record from Chhasra Formation (Early Miocene), Eastern Kutch, Gujarat." Journal of Palaeosciences 62, no. (1-2) (December 31, 2013): 149–55. http://dx.doi.org/10.54991/jop.2013.340.

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A moderately diverse palynoflora consisting of angiospermous pollen and pteridophytic spores has been recorded from poorly known Chhasra Formation (Early Miocene) exposed in a section near Palasawa in eastern Kutch, Gujarat, western India. Dinoflagellate cysts are absent in the section, whereas the fresh water Centropyxis, a testate amoeba, is recorded. Among the important genera recovered are: Hammenisporis, Khariasporites, Acanthotricolpites, Spinizonocolpites, Spinomonocolpites, Retitrescolpites, Meliapollis, Ctenolophonidites, Palaeomalvaceaepollis, Graminidites and Ericipites. Preliminary qualitative and quantitative assessment reveals the dominance of angiospermous pollen grains over pteridophytic spores, and an overall warm and humid coastal climate with tropical rain forest in a lowland coastal setting. Ongoing work in this newly identified section may reveal greater insights into diversity and significance of the Chhasra palynoflora.
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DYUZHOVA, K. V. "SUBRECENT POLLEN ASSEMBLAGES IN ALLUVIAL DEPOSITS OF THE DON AND KUBAN RIVERS AND THEIR SIGNIFICANCE FOR PALAEOGEOGRAPHIC RECONSTRUCTIONS." Lomonosov Geography Journal 79, no. 1 (2024) (March 2, 2024): 48–60. http://dx.doi.org/10.55959/msu0579-9414.5.79.1.4.

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The paper presents the results of studying modern alluvial deposits of the Don and Kuban rivers by the pollen analysis method. The study was carried out to clarify methodological issue, including the movement of pollen and spores by flowing waters. The obtained data show that pollen assemblages of river sediments formed in the process of pollen mixing by water and air characterize the composition of the regional vegetation cover rather than local nearriver plant groups. According to the results for the subrecent sediments of the Don River the transfer of pollen grains and spores by water was insignificant, which can be clearly seen at the border of the forest-steppe and steppe zones. Pollen assemblages of the forest-steppe zone contain 50% of tree species pollen, while in the steppe zone, including its northern part, tree species make up less than 30-35%. Sporadic forest elements such as Picea pollen, Lycopodium species spores and Sphagnum mosses in alluvial deposits of the steppe section of the Don River, as well as in the subrecent sediments of the Sea of Azov, could be neglected in the palaeoreconstructions. The composition of subrecent pollen assemblages of the Kuban River sediments is less variable from the middle course to the mouth with rather stable ratio of components. Pollen of the Caucasian flora elements (Fagus orientalis, Carpinus caucasica) is poorly dispersed by water from high and midmountain landscapes of the upper reaches of the river. The comparison of pollen assemblages from alluvial and marine (the Sea of Azov) sediments have shown that the distortion of fossil assemblages’ composition due to material input by water is minimal
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41

El-Ghazaly, Gamal A., and William A. Jensen. "Development of wheat (Triticum aestivum) pollen wall before and after effect of a gametocide." Canadian Journal of Botany 68, no. 11 (November 1, 1990): 2509–16. http://dx.doi.org/10.1139/b90-315.

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Light and electron microscopy studies show that pollen wall development in plants treated with the gametocide RH0007 and untreated plants was similar until the stage at which sporopollenin is normally deposited on the wall. At this stage, the pollen wall of treated plants is 80% thinner than that of the control. Shortly after this stage, the pollen grains in the treated plants collapse and abort. We conclude that the gametocide clearly acts through the inhibition of sporopollenin formation, which results in pollen death. As sporopollenin is found only in the pollen wall of seed plants and the spores of nonseed plants, harm to other parts of the plant is not expected to occur. Key words: pollen wall development, Triticum aestivum, gametocide.
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42

Ajikah, Linus Bashie, Shadrak Alebiosu Olugbenga, Emuobosa Akpo Orijemie, and Dough Owojoku Onah. "review of aeropalynology research in Nigeria." Allergologia et Immunopathologia 49, no. 6 (November 1, 2021): 31–38. http://dx.doi.org/10.15586/aei.v49i6.241.

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Background: Aeropalynology is a branch of palynology that studies the content of atmospheric pollen grains and spores. The amount, concentration, and distribution of these aerospora are influenced by the seasonal flowering of parent plants and variations in climatic conditions as well as local and regional variabilities. Atmospheric pollen grains and spores are diverse and have been identified as major biological particles that trigger immune cells to release inflammatory chemical mediators, inducing respiratory-linked and allergic conditions, such as polli-nosis, among susceptible individuals. Objective: The burden of these allergic conditions on patients, families, healthcare systems, and governments has risen globally, thereby affecting developing countries, including Nigeria, wherein the financial and infrastructural institutions are not effective enough to mitigate these challenges. Avoidance of allergenic aerospora is an effective mode of addressing pollinosis with its associated conditions. However, there is a need to ascertain the atmospheric quantity, diversity, and pattern of occurrence of allergenic pollen/spores. Results: In this paper, we reviewed published articles on aeropalynology in Nigeria with atten-tion to the design and duration of the study and the used equipment. We further investigated whether identification and quantification of allergy-causing palynomorphs was part of published articles’ foci. Conclusion: The availability of such data/information is crucial for reducing epidemiological uncertainties, enhancing the diagnosis of allergic conditions, and securing a robust set of mitigation strategies and/or effective treatment of these conditions in Nigeria.
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43

Pant, D. D., and Rita Singh. "Possible fossil sporae dispersae of hepaticae and anthocerotales in the fossil records." Journal of Palaeosciences 39, no. (1-3) (December 31, 1990): 20–36. http://dx.doi.org/10.54991/jop.1990.1679.

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The paper attempts to find the characters which can distinguish the spores of Hepaticae and Anthocerotales from iso- or micro-spores of pteridophytes and pollen grains of gymnosperms and angiosperms for the identification of possible fossil Sporae dispersae of bryophytes reported from different geological horizons. The problem was approached by looking for characters in fossil spores which are (i) exclusively bryophytic, (ii) prevailingly bryophytic, and (iii) closely matching characters of in situ spores of fossil bryophytes in a first-hand comparison. Our account also takes into consideration the Sporae dispersae which were described or suspected by previous workers as those of bryophytes but which could equally well belong to pteridophytes.
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44

Mandaokar, B. D. "Occurrence of palynofossils from the Tirap River section (Disang Group), Tinsukia District, Assam." Journal of Palaeosciences 48, no. (1-3) (December 31, 1999): 239–43. http://dx.doi.org/10.54991/jop.1999.1307.

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Disang shale exposed on the Tirap River section yielded 23 genera and 24 species of palynomorphs. The palynoassemblage is dominated by pteridophytic spores and angiospermic pollen grains, whereas gymnospermic elements are rare. The presence of Striatriletes, Polypodiisporites, Schizaeoisporites, Striacolporites, Lakiapollis, Tricolpopollenites, Phragmothyrites and Inapertisporites suggests an Eocene age to the assemblage.
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45

Santos, Artai A., Laura Piñuela, Iván Rodríguez-Barreiro, Jose Carlos García-Ramos, and José B. Diez. "Palynology from “The Jurassic Dinosaur Coast” of Asturias (Lastres Fm., Northwestern Spain): Palynostratigraphical and Palaeoecological Insights." Biology 11, no. 12 (November 24, 2022): 1695. http://dx.doi.org/10.3390/biology11121695.

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Abundant fossils of vertebrates (mainly footprints and bones of dinosaurs) and numerous invertebrates occur in the Upper Jurassic deposits of the Lastres Formation in the Asturias region, North of Spain. However, no palynological study has been published from this geological formation; therefore, much palaeoenvironmental and palaeoecological information is still unknown. In this study, a total of 62 morphospecies, belonging to 49 different morphogenera were identified, including pollen, spores, algae remains, fungi spores, dinoflagellates, foraminifera, and scolecodonts from four different locations on the Asturian coast. Spores are the dominant group of palynomorphs, both in diversity and abundance, contrasting with the minor diversity of pollen grains. The age of some key taxa indicates that the palynological assemblage cannot be older than the Kimmeridgian, suggesting a Kimmeridgian-Tithonian age. The botanical and environmental affinities of the pollen and spores indicate the presence of different plant assemblages, including plant communities from humid areas such as the margin of rivers and small freshwater ponds that were dominated by bryophytes and ferns, and a coastal plant community that would inhabit arid areas and would be dominated by gymnosperms and some pteridophytes. The SEM analyses of wood remains show the abundance of charcoalified remains suggesting that wildfires were usual in The Dinosaur Coast of Asturias during the Kimmeridgian.
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46

Pal, Chhaya, and S. K. Roy. "Palynology of the Permian coal from Barjora of West Bengal, India." Journal of Palaeosciences 47 (December 31, 1998): 29–31. http://dx.doi.org/10.54991/jop.1998.1270.

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Palynological investigations carried out on bore-hole BRJ-003 Barjora of Bankura District in West Bengal, India shows that the assemblage is rich in disaccate pollen grains with predominance of Scheuringipollenites, Straitopodocarpites, Striatopicetes, Lahirites along with a few trilete-tetrahedral spores and monosulcates. The general characteristics of the assemblage indicate Barakar palynoflora.
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47

Ewing, Michael E., Carl A. Reese, and Matthew A. Nolan. "The potential effects of percolating snowmelt on palynological records from firn and glacier ice." Journal of Glaciology 60, no. 222 (2014): 661–69. http://dx.doi.org/10.3189/2014jog13j158.

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AbstractThe effects of meltwater percolation on pollen in snow, firn and glacial ice are not fully understood and currently hamper the use of pollen in ice-core studies of paleoclimate. Several studies have suggested that, due to grain size, pollen is not mobilized by meltwater transport. However, these findings contradict many ice-core pollen studies that show pollen concentrations in snow and firn are much higher than concentrations found in the ice layers they eventually form. This study addresses one aspect of this question by investigating whether meltwater percolation can effectively transport pollen within a snowpack. We used nine Styrofoam coolers filled by natural snow accumulation. The coolers were tested in three groups of three replicates each to simulate different glacier snowpack conditions, and spiked at the surface with a known amount of Lycopodium marker spores. The snow was melted to two-thirds the original volume, sampled stratigraphically and tested for spore concentrations. Meltwater effluent was also collected and examined. Results show substantial vertical and horizontal spore transport during the experiment. Peak spore concentrations were found in the bottommost snow layer or in the meltwater effluent in eight of nine coolers, indicating that the majority of surface spores were transported through the snowpack via meltwater percolation and/or runoff.
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48

Luz, Cynthia F. P. da, Ortrud M. Barth, and Cleverson G. Silva. "Modern processes of palynomorph deposition at lakes of the northern region of the Rio de Janeiro State, Brazil." Anais da Academia Brasileira de Ciências 82, no. 3 (September 2010): 679–90. http://dx.doi.org/10.1590/s0001-37652010000300016.

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Palynological analysis of pollen, Pteridophyta spores and algae deposited in the superficial sediments at Lagoa de Cima and Lagoa do Campelo Lakes, located in the north of Rio de Janeiro state, was used to determine the spatial variation of the palynomorphs deposition. A total of 67 pollen types were identified at Lagoa de Cima, with an expressive contribution of regional arboreous taxa, hydrophytes and ruderal plants of the pastureland. The depositional pattern of palynomorphs depends on the fluvial leakage, the proximity of the local sedimentation to the inlet of the Imbé and Urubu Rivers and the bathymetry of lake bottom. The highest concentrations of palynomorphs were observed in the decentralized and less deeper area, without the interference of the northeastern wind. At Lagoa do Campelo, a total of 58 pollen types were identified, among which the majority of the pollen grains came from hydrophytes, with the highest concentrations found along the northeastern shore. The southeastern shore showed high percentages of pollen and spores with degraded exine and mechanical damage, due to the transport through the lakeby the currents caused by the wind, confirmed by the depositional trend of damaged palinomorphs along the same direction as the prevailing winds.
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Mander, Luke, Mao Li, Washington Mio, Charless C. Fowlkes, and Surangi W. Punyasena. "Classification of grass pollen through the quantitative analysis of surface ornamentation and texture." Proceedings of the Royal Society B: Biological Sciences 280, no. 1770 (November 7, 2013): 20131905. http://dx.doi.org/10.1098/rspb.2013.1905.

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Taxonomic identification of pollen and spores uses inherently qualitative descriptions of morphology. Consequently, identifications are restricted to categories that can be reliably classified by multiple analysts, resulting in the coarse taxonomic resolution of the pollen and spore record. Grass pollen represents an archetypal example; it is not routinely identified below family level. To address this issue, we developed quantitative morphometric methods to characterize surface ornamentation and classify grass pollen grains. This produces a means of quantifying morphological features that are traditionally described qualitatively. We used scanning electron microscopy to image 240 specimens of pollen from 12 species within the grass family (Poaceae). We classified these species by developing algorithmic features that quantify the size and density of sculptural elements on the pollen surface, and measure the complexity of the ornamentation they form. These features yielded a classification accuracy of 77.5%. In comparison, a texture descriptor based on modelling the statistical distribution of brightness values in image patches yielded a classification accuracy of 85.8%, and seven human subjects achieved accuracies between 68.33 and 81.67%. The algorithmic features we developed directly relate to biologically meaningful features of grass pollen morphology, and could facilitate direct interpretation of unsupervised classification results from fossil material.
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50

Mendes, Mário Miguel, and Else Marie Friis. "The Nossa Senhora da Luz flora from the Early Cretaceous (early Aptian-late Albian) of Juncal in the western Portuguese Basin." Acta Palaeobotanica 58, no. 2 (December 1, 2018): 159–74. http://dx.doi.org/10.2478/acpa-2018-0015.

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AbstractA new fossil flora is described from the Early Cretaceous of the western Portuguese Basin, based on a combined palynological-mesofossil study. The fossil specimens were extracted from samples collected in the Nossa Senhora da Luz opencast clay pit complex near the village of Juncal in the Estremadura region. The plant-bearing sediments belong to the Famalicão Member of the Figueira da Foz Formation, considered late Aptianearly Albian in age. The palynological assemblage is diverse, including 588 spores and pollen grains assigned to 30 genera and 48 species. The palynoflora is dominated by fern spores and conifer pollen. Angiosperm pollen is also present, but subordinate. The mesofossil flora is less diverse, including 175 specimens ascribed to 17 species, and is dominated by angiosperm fruits and seeds. The mesofossil flora also contains conifer seeds and twigs as well as fossils with selaginellaceous affinity. The fossil assemblage indicates a warm and seasonally dry climate for the Nossa Senhora da Luz flora.
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