Pollen Species Research Articles

Host Range Expansion of Nest-Parasitic Moths Pyralis regalis and Hypsopygia mauritialis in Social Wasp Nests: New Findings and Implications for Biological Control

Parasitic moths are common in social wasp (Hymenoptera) nests, attacking many species of Polistinae and a few species of Vespinae. In the Republic of Korea, two moth species are known to parasitize the brood of Polistes rothneyi koreanus: Pyralis regalis (Pyralidae) and Anatrachyntis japonica (Cosmopterigidae). Although previously reported elsewhere, a novel case of parasitization was recently documented in the Republic of Korea, in which Hypsopygia mauritialis (Pyralidae) was identified in the nests of social wasps. Pyralis regalis is the most common parasitic moth in the Republic of Korea, feeding on the nests of 11 species of social wasps, mostly the Korean Vespa species. To that list of hosts, we add a species of Dolichovespula and two species of Polistes. Parasitism of Vespa velutina nigrithorax, an invasive alien hornet, by both P. regalis and H. mauritialis, was observed for the first time. However, their potential to control invasive alien hornets is expected to be low. This study provides new insights into the diversity of nest-parasitic moths in social wasp nests and their hosts in the Republic of Korea, and highlights the potential for these moths to impact pest populations.

Long‐term arid and hot climate during earlyMid‐Cretaceousindicate by unvaried Cheirolepidiaceae‐dominant palynoflora from the Liupanshan Basin, China

The Mid‐Cretaceous was characterized by long‐term and stabilized high temperatures confirmed by numerous palaeoclimatic information from marine sedimentary archives. However, few terrestrial records have yet been employed to verify the terrestrial humidity under this long‐term hot climate. The Liupanshan Basin, located in central China during the Cretaceous contains thick Aptian‐Albian sediments. Here, we reconstructed a long‐term palaeovegetational record during late Aptian to Albian from the Huoshizhai Section and Sikouzi Section, Liupanshan Basin. Five palynological assemblages were defined from the bottom to top of these strata, and a total of 124 types of palynomorphs including 47 spore species and 77 gymnosperm pollen species were recognized in the palynological assemblages. Sporopollen analysis revealed that the spore‐pollen spectra of Huoshizhai Section were dominated byPerinopollenitesand Bisaccate pollen. In Sikouzi section, theClassopolliscontent dominate in all samples (average 63.8%), with a few other pollen, including conifer bisaccates types,Perinopollenites,Jiaohepollis,Ephedripites,Cycadopitesand a few spores. The sporopollen assemblage reflected that the flora of the central Asia continent gradually changed from Taxodiacean‐dominated to Cheirolepidiaceae‐dominated in the late Aptian and the Albian, which further indicates that the central Asia continent palaeoclimate gradually changed from a wet and cold climate to a long‐term dry and hot climate with small fluctuation. In addition, theClassopolliscontent also presented a slightly increased trend from late Aptian to late Albian, which probably indicated a gradually intensified hot and dry climate. The thermophilic floral changes and warmer/cooler ratio of the Sporomorph Ecogroup Model at the middle Madonghshan Formation also shows slightly decreased trends which correspond to the global short‐term cooling events at the Aptian‐Albian transition.

The Clinical Significance of Pollen and Fungi Concentrations for Allergic Rhinitis: A Three-Year Study.

The relationship between disease severity and exposure to allergensin allergic rhinitis (AR) patientsisnot fully clarified presently.We aimed to detect the correlation between airborne pollen and fungi concentrations in a Mediterranean region with symptomscores. A total of 98 patients suffering from AR rated their symptoms at the time of exacerbation using the Total 5 Symptoms Score (T5SS) and the Visual Analogue Scale (VAS). Patients' quality of life (QoL) was estimated by using either disease-specific (Rhinoconjunctivitis Quality of Life Questionnaire(RQLQ) and mini-RQLQ) or generic (Short-Form 36 (SF-36) and Beck Depression Inventory (BDI)) questionnaires. All patients' responses were correlated with aerobiological data. Skin prick tests (SPTs) were used to detect sensitivities to the most common registered pollen and fungi species. A significant positive correlationbetween total pollen and fungi counts and disease-specific questionnaires was found only for the RQLQ. Accordingly, a significant positive correlation was found between total pollen and fungi counts and T5SS (r = 0.655, p = 0.021), with breathing (r = 0.620, p = 0.032) and sneezing (r = 0.660, p = 0.020) being strongly affected. Moreover, a tendency towarda higher VAS score was found as total pollen and fungi counts increased (r = 0.523, p = 0.081). We found a significant correlation between patients' symptoms and pollen and fungal air concentrations. Our results emphasize the clinical significance of pollen and fungi maps in everyday clinical practice.

Evaluation of grass pollen quality control for allergy test kit production using pollen morphological characters

Grass pollen is one of the leading causes of allergies in throughout the world. The symptom level depends on the personal immunity. Pollen allergy test kits are suitable for detecting allergic symptoms, which they are produced from pure pollen of specific species. The production of pollen allergy testing kits requires accurate botanical standards and identification for the process of quality control of raw materials basing on Thai Food and drug ministration (Thai FDA). To produce allergy test kit, we focused on the pollen of these 6 common grass species and also use pollen morphological characters for detection and identification. Therefore, this study focused on the method for qualification control and standardization for prototype product of grass pollen allergy testing kit. Six common grass species as Megathyrsus maximus (Jacq.) B.K.Simon & S.W.L. Jacobs, Oryza sativa L., Sorghum bicolor (L.) Moench, Urochloa eminii (Mez) Davidse, Urochloa mutica (Forssk.) T.Q.Nguyen and Zea mays L.). The criteria were: 1) common in Thailand and Southeast Asia; 2) high density in the atmosphere; and 3) severity of the allergic reaction. The modified acetolysis were applied for samples preparation. The pollen morphological (polar and equatorial axes, exine, porus, annulus and ornamentation) were observed and measurement under light and scanning electron microscope. The character matrix was analyzed based on a regression tree and Tukey’s HSD test to assess support for the different pollen morphological characters. The distinguished character is ornamentation. The results were successfully described the pollen species and showed that the pollen morphologies were useful for contaminated detection. In addition, this method was suitable applied for qualification control of the raw materials for grass pollen allergy testing kits production.

Effects of pollen concentration on allergic rhinitis in children: A retrospective study from Beijing, a Chinese megacity

With global climate change and rapid urbanization, the prevalence of allergic diseases caused by pollen is rising dramatically worldwide with unprecedented complexity and severity, especially for children in mega-cities. However, because of the lack of long time-series pollen concentrations data, the accurate evaluation of the impact of pollen on allergic rhinitis (AR) was scarce in the Chinese metropolis. A generalized additive model was used to assess the effect of pollen concentration on pediatric AR outpatient visits in Beijing from 2014 to 2019. A stratified analysis of 10 pollen species and age-gender-specific groups was also conducted during the spring and summer-autumn peak pollen periods separately. Positive associations between pollen concentration and pediatric AR varied with the season and pollen species were detected. Although the average daily pollen concentration is higher during the spring tree pollen peak, the influence was stronger at the summer-autumn weed pollen peak with the maximum relative risk 1.010 (95% CI 1.009, 1.011), which was higher than the greatest relative risk, 1.003 (95% CI 1.002, 1.004) in the spring peak. The significant adverse effects can be sustained to lag10 during the study period, and longer in the summer-autumn peak (lag13) than in the spring peak (lag8). There are thresholds for the health effects and they varied between seasons. The significant effect appeared when the pollen concentration was higher than 3.74 × 105 grain·m−2·d−1 during the spring tree pollen peaks and 4.70 × 104 grain·m−2·d−1 during the summer-autumn weed pollen peaks. The stratified results suggested that the species-specific effects were heterogeneous. It further highlights that enough attention should be paid to the problem of pollen allergy in children, especially school-aged children aged 7–18 years and weed pollen in the summer-autumn peak pollen period. These findings provide a more accurate reference for the rational coordination of medical resources and improvement of public health.

Descriptive systematics of Upper Palaeocene–Lower Eocene pollen and spores from the northern Niger Delta, south-eastern Nigeria

Fossil pollen and spores are a vital source of information on the geological history of tropical vegetation including reconstructions of vegetation diversity and composition. However, such work relies on a sound taxonomic framework, and this is challenging to achieve because of the large number of pollen and spore morphotypes that are encountered in palynological preparations from tropical sediments. In tropical West Africa, for example, extensive taxonomic work on Cretaceous–Paleogene pollen and spores was undertaken in the later part of the twentieth century, but more recent palynological work has focussed on stratigraphy and basin evolution, and there is a need for additional taxonomic work on the pollen and spores of this region. We have undertaken a descriptive systematic study of pollen and spores (sporomorphs) from 15 sediment samples spanning the Upper Palaeocene–Lower Eocene of south-eastern Nigeria. A palynoflora consisting of 29 spores, two gymnosperm pollen grains, and 138 angiosperm pollen grains is described. Two new spore species are proposed, and one new genus and 18 new species of angiosperm pollen are proposed. The general vegetation type represented by the palynoflora consists of palm-dominated swamps, perhaps with mangroves. The richness of each sample ranges from 29 to 76 sporomorph taxa, and rarefaction analysis suggests an increase in diversity from the Palaeocene to the Eocene in this region. Samples from the Palaeocene Upper Nsukka Formation are dominated by pollen with botanical affinities to the Arecaceae (palms) and Araceae (arums), and this assemblage is very similar to the Palaeocene in the Neotropics.

Identification of Candidate Genes Involved in the Determinism of Pollen Grain Aperture Morphology by Comparative Transcriptome Analysis in Papaveraceae.

In the last decade, certain genes involved in pollen aperture formation have been discovered. However, those involved in pollen aperture shape remain largely unknown. In Arabidopsis, the interaction during the tetrad development stage of one member of the ELMOD protein family, ELMOD_E, with two others, MCR/ELMOD_B and ELMOD_A, can change the morphology of apertures from colpus (elongated) to pore (round). Here, comparative transcriptome analysis is used to identify candidate genes involved in the determination of pollen aperture morphology in Papaveraceae (order Ranunculales). Furthermore, the role of ELMOD genes in the genetic determinism of aperture shape was tested by comparative analysis of their expression levels using RNA-seq data and RT-qPCR. Two pairs of species belonging to two different subfamilies were used. Within each pair, one species has colpate pollen and the other porate (Fumarioideae-Dactylicapnos torulosa, 6-colpate, and Fumaria bracteosa, pantoporate; Papaveroideae-Eschsholzia californica, 5-7 colpate, and Roemeria refracta, 6-porate). The transcriptomes were obtained at the tetrad stage of pollen development. A total of 531 DEGs were found between the colpate and porate pollen species groups. The results from RNA-seq and RT-qPCR indicate that pollen aperture shape is not determined by the relative expression levels of ELMOD family genes in Papaveraceae. However, genes related to callose wall formation or cytoskeleton organisation were found, these processes being involved in pollen aperture formation. In addition, transcriptomes from anthers with pollen during the tetrad stage of three species (D. torulosa, R. refracta, and F. bracteosa) were obtained for the first time. These data will be available for further studies in the field of floral evolution and development.

Phytolith analyses of tropical plants and topsoil from western Peninsular Malaysia and their implications for paleoenvironmental reconstruction

The underrepresentation of many important rainforest species in pollen records still hinders accurate paleovegetation reconstructions in tropical Southeast Asia. In this study, we conducted a modern phytolith study of 141 plant and 15 surface soil samples around the forests of Jerai Hill in western Peninsular Malaysia to evaluate the potential of phytolith assemblages as a proxy for indicating tropical vegetation types. In the plant samples, including many Dipterocarpaceae species, tracheary annulate/helical phytoliths occur most commonly, followed by silicified epidermis, silicified stomata, elongate entire, sclereid, trichomes, irregular. A few diagnostic phytoliths with unique morphological features are found in dicotyledonous trees, palms, and ferns, such as spheroid ornate (sph_orn) and spheroid echinate (sph_ech). In contrast, the phytolith assemblage of surface sediment is dominated by sph_orn, sph_ech, and spheroid psilate. This suggests that similar to pollen, the contribution from dominating forest vegetation rich in Dipterocarpaceae species is obscure in phytolith deposits. However, phytolith analysis highlights the representation of monocotyledons and a few dicotyledonous trees. The more sensitive indication of Poaceae short-cell phytoliths than pollen for parent plants implies that their ratio to forest indicator phytoliths might be a valuable proxy of landscape openness. Additionally, the statistical analysis confirms that phytolith assemblages in the heath forest are slightly different from those in the lowland dipterocarp forest, exhibiting their potential to indicate various vegetation types.

A Laboratory Evaluation of the New Automated Pollen Sensor Beenose: Pollen Discrimination Using Machine Learning Techniques.

The monitoring of airborne pollen has received much attention over the last decade, as the prevalence of pollen-induced allergies is constantly increasing. Today, the most common technique to identify airborne pollen species and to monitor their concentrations is based on manual analysis. Here, we present a new, low-cost, real-time optical pollen sensor, called Beenose, that automatically counts and identifies pollen grains by performing measurements at multiple scattering angles. We describe the data pre-processing steps and discuss the various statistical and machine learning methods that have been implemented to distinguish different pollen species. The analysis is based on a set of 12 pollen species, several of which were selected for their allergic potency. Our results show that Beenose can provide a consistent clustering of the pollen species based on their size properties, and that pollen particles can be separated from non-pollen ones. More importantly, 9 out of 12 pollen species were correctly identified with a prediction score exceeding 78%. Classification errors occur for species with similar optical behaviour, suggesting that other parameters should be considered to provide even more robust pollen identification.

Identification and characterization of honeybee flora calendar in Southwest Jimma Zone, Ethiopia

Abstract. Mossie T, Worku H. 2023. Identification and characterization of honeybee flora calendar in Southwest Jimma Zone, Ethiopia. Asian J For 7: 54-66. The study was conducted to identify, characterize and document major bee forages, develop an appropriate flora calendar, their phenology, and pollen potential in the various agro-ecological conditions of the Jimma Zone, Ethiopia. A total of 90 beekeepers were purposefully selected from three districts and interviewed to get primary data. The density and abundance of flowering plants were determined using quadrat sampling techniques. In addition, pollen specimens were collected using pollen traps at seven-day intervals and were also traced back to plant species level under a light microscope. The study has revealed the presence of 141 pollen and/or nectar-source honeybee plant species belonging to sixty-two families in the study area. Herbs were the most dominant bee flora growth forms, accounting for 62 (44%) of a total of 141 honeybee plant species, followed by trees at 48 (34%) and shrubs at 31 (22%), respectively. The herbaceous plant had a greater density value of plant species per plot than did trees and shrubs. One hundred fifteen (81.6%) were both sources of pollen and nectar, whereas fifteen (10.6%) were pollen sources and the remaining eleven (7.8%) were nectar-source plant species. The Shannon diversity index and evenness were found to be 2.8 and 0.6, respectively. This indicated that the study area has a rich bee floral plant species and is suitable for beekeeping. Two main flowering periods of honeybee plants were followed by two honey flow seasons. Therefore, beekeepers should follow the floral calendar of honeybee plants to exploit the potential of the area for honey production.

Application of In Vitro Tests to Establish an Accurate Diagnosis of Double Sensitization to Vespula and Polistes Species.

Application of In Vitro Tests to Establish an Accurate Diagnosis of Double Sensitization to Vespula and Polistes Species.

Detection of ice core particles via deep neural networks

Abstract. Insoluble particles in ice cores record signatures of past climate parameters like vegetation dynamics, volcanic activity, and aridity. For some of them, the analytical detection relies on intensive bench microscopy investigation and requires dedicated sample preparation steps. Both are laborious, require in-depth knowledge, and often restrict sampling strategies. To help overcome these limitations, we present a framework based on flow imaging microscopy coupled to a deep neural network for autonomous image classification of ice core particles. We train the network to classify seven commonly found classes, namely mineral dust, felsic and mafic (basaltic) volcanic ash grains (tephra), three species of pollen (Corylus avellana, Quercus robur, Quercus suber), and contamination particles that may be introduced onto the ice core surface during core handling operations. The trained network achieves 96.8 % classification accuracy at test time. We present the system's potential and its limitations with respect to the detection of mineral dust, pollen grains, and tephra shards, using both controlled materials and real ice core samples. The methodology requires little sample material, is non-destructive, fully reproducible, and does not require any sample preparation procedures. The presented framework can bolster research in the field by cutting down processing time, supporting human-operated microscopy, and further unlocking the paleoclimate potential of ice core records by providing the opportunity to identify an array of ice core particles. Suggestions for an improved system to be deployed within a continuous flow analysis workflow are also presented.

An Object Detection System for Identifying Pollen Species

Exposure to airborne allergens, including pollen, is a primary trigger of allergic airway diseases (AAD) or AAD-like symptoms. Pollen has been the subject of international monitoring using manual counts for decades, a labor-intensive process. Current methods of identification are limited in terms of species and timing. We present a method for identifying pollen species in real-time.

Caste-specific storage of dopamine-related substances in the brains of four Polistes paper wasp species.

How the role of dopamine differs according to the evolution of eusociality and how it is required in the flexible society of Polistes paper wasps need further clarification. In the present study, we compared the storage and usage of dopamine-related substances in brains between the castes of paper wasps. The head widths, lipid stores in the abdomen, and levels of biogenic amines in the brains were measured in newly emerged females before male emergence (workers) and after male emergence (gynes) in four Polistes species. The head widths and the lipid stores were significantly larger in gynes than workers in P. snelleni, P. rothneyi, and P. jokahamae, whereas they did not differ between castes in P. chinensis. The levels of dopamine precursors in the brains were significantly higher in gynes than workers in P. snelleni, P. chinensis, and P. rothneyi, whereas those of dopamine and its metabolites did not differ between castes in these species. In P. jokahamae, the levels of dopamine precursors and dopamine in the brains did not differ between castes, but those of a dopamine metabolite were significantly higher in gynes than workers. Thus, the caste differences in the levels of dopamine-related substances did not always match body sizes and nutritional reserves. Foundresses in P. rothneyi had significantly lower levels of dopamine precursors and higher levels of dopamine and its metabolite than newly emerged gynes. These results suggested that in several Polistes species, dopamine precursors were stored in the brain without dopamine biosynthesis at emergence, and then converted into dopamine in foundresses during colony founding. These neuroendocrinal states in Polistes species largely differed from those in eusocial bees.

Patterns of Phenolic Compounds in Betula and Pinus Pollen.

In this study, phenolic compounds and their antioxidant activity in the pollen of anemophilous Betula and Pinus were determined. Spectrophotometric, high-performance thin-layer and liquid chromatography methods were applied. Free phenolic compounds (free PC) and phenolic compounds bound to the cell wall (bound PC) were analysed in the pollen extracts. Regardless of the pollen species, their content was 20% higher than that in bound PC extracts. Pinus pollen extracts contained 2.5 times less phenolic compounds compared to Betula. Free PC extraction from the deeper layers of Pinus pollen was minimal; the same content of phenolic compounds was obtained in both types of extracts. The bioactivity of pollen (p < 0.05) is related to the content of phenolic compounds and flavonoids in Betula free PC and in bound PC, and only in free PC extracts of Pinus. Rutin, chlorogenic and trans-ferulic acids were characterised by antioxidant activity. Phenolic acids accounted for 70-94%, while rutin constituted 2-3% of the total amount in the extracts. One of the dominant phenolic acids was trans-ferulic acid in all the Betula and Pinus samples. The specific compounds were vanillic and chlorogenic acids of Betula pollen extracts, while Pinus extracts contained gallic acid. The data obtained for the phenolic profiles and antioxidant activity of Betula and Pinus pollen can be useful for modelling food chains in ecosystems.

北京主要气传致敏花粉年浓度峰值日期预测

PDF HTML阅读 XML下载 导出引用 引用提醒 北京主要气传致敏花粉年浓度峰值日期预测 DOI: 10.5846/stxb202202220416 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 北京市科技计划课题（Z191100009119013） Prediction of date of annual maximum concentration of main airborne allergenic pollen in Beijing Author: Affiliation: Fund Project: Beijing Municipal Science and Technology Project(Z191100009119013) 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:花粉是我国北方引发过敏性鼻炎最主要过敏原，花粉症发病期与花粉浓度高峰期吻合。基于北京地区2012至2020年花粉季多站、逐日分类花粉浓度观测数据分析，得出北京地区花粉浓度在3月上旬至5月中旬（可进一步划分为3月中旬至4月上旬和4月下旬至5月上旬两个高峰期）和8月中旬至9月中旬分别存在两个高峰期，第一个高峰期内优势致敏花粉种类为柏科、杨柳科和松科，第二个高峰期内优势致敏花粉种类为桑科、菊科蒿属和藜科。根据优势致敏花粉年浓度峰值日期观测数据，使用与花粉采样站点位置相匹配的逐日气象观测数据累积值，基于作物模型概念和模糊逻辑原理建立了北京地区主要气传致敏花粉年浓度峰值日期预测模型。经检验，柏科、杨柳科、松科、桑科、菊科蒿属和藜科花粉模型预测准确率分别为87.8%、80.0%、64.4%、86.7%、78.8%和81.8%。基于北京地区主要气传致敏花粉年浓度峰值日期预测模型可为本地花粉症防治提供理论参考。 Abstract:The prevalence and severity of pollen-induced pollinosis has been increasing yearly worldwide in recent years. Pollen is the main allergen causing allergic rhinitis in North China and the onset period of airborne allergenic pollen-induced pollinosis coincides with the peak period of pollen concentration. As one of the mega-cities in the northern region of China, Beijing is becoming increasingly aware of the problems caused by allergenic pollen. Based on the analysis of 12 pollen sampling stations daily classified pollen concentration observation data during pollen season in Beijing from 2012 to 2020, there were two peak periods of pollen concentration in Beijing from early March to mid-May (it could be further divided into two peak periods from mid-March to early April and from late April to early May) and from mid-August to mid-September, respectively. The dominant allergenic pollen species in the first peak period were Cupressaceae, Salicaceae (from early March to mid-April, the annual average concentration accounted for 39.1% and 18.2% respectively) and Pinaceae (from mid-April to early May, the annual average concentration accounted for 18.2%), and the dominant allergenic pollen species in the second peak period were Moraceae, Artemisia and Chenopodiaceae (from mid-August to mid-September, the annual average concentration accounted for 34.4%, 30.4% and 12.7% respectively). The annual maximum concentration of dominant airborne allergenic pollen in Beijing varied significantly among stations and pollen seasons, and fluctuated significantly. In contrast, the variation of the dates of annual maximum pollen concentration of the same species is relatively stable, and its prediction research work is more meaningful for pollen-induced pollinosis control. Based on the observation data of annual maximum concentration of dominant airborne allergenic pollen and the cumulative value of daily meteorological observation data matched with the location of pollen sampling stations, a prediction model of date of annual maximum concentration of main airborne allergenic pollen in Beijing is established based on the principle of crop growth model and fuzzy logic. The results showed that the prediction accuracy of pollen models of Cupressaceae, Salicaceae, Pinaceae, Moraceae, Artemisia and Chenopodiaceae were 87.8%, 80.0%, 64.4%, 86.7%, 78.8% and 81.8%, respectively. Using a model based on fuzzy logic principle and driven by the cumulative values of daily meteorological elements for pollen annual maximum concentration date, combined with the high-resolution regional numerical weather prediction model in Beijing, we can make a reasonable prediction of the time of maximum pollen concentration of different airborne allergenic pollens and provide a theoretical reference for the prevention and control of local airborne allergenic pollen-induced pollinosis. 参考文献 相似文献 引证文献

Mid- to late Holocene vegetation response to relative sea-level fluctuations recorded by multi-proxy evidence in the Subei Plain, eastern China

Reconstructing Holocene changes in regional sea level is useful for understanding future sea-level scenarios. In this paper we examined the sedimentology, pollen, foraminifera, and organic matter properties of a well-dated profile from the Subei Basin that spans the last 6.7 ka. By integrating our findings with the archaeological record, we investigated mid- to late Holocene vegetation responses to relative sea-level fluctuations and considered the impact of climatic variations on cultural development. In the middle Holocene, the rapid and abrupt expansion of salt marsh vegetation (Chenopodiaceae, Cyperaceae, and Poaceae) suggests a relative rise in sea level. From 5.7 to 4.2 cal ka BP, lowland swamps were settled by Neolithic communities, as indicated by peak levels of microscopic charcoal and a significant rise in herbaceous pollen species, such as Cyperaceae, Typha, Myriophyllum, and Poaceae. From 4.2 to 3.7 cal ka BP, a major increase in Chenopodiaceae abundance and a δ13C excursion were observed along with a decrease in Cyperaceae and Poaceae levels, which revealed that human activity significantly decreased following the 4.2 ka climate event. Evidence suggests that the area under investigation experienced a relatively high sea level between 6.7 and 6.0 ka, a relative decrease in sea level between 6.0 and 5.7 ka, a steady sea-level condition between 5.7 and 4.2 ka, and gradual replacement by a freshwater marsh between 5.7 and 4.2 ka. The pollen and δ13 C records demonstrate that the relative sea level rose quickly from 4.2 to 3.7 ka, which could correspond to the 4.2 ka event. Enhanced El Niño-Southern Oscillation (ENSO) variance and intense climatic events in eastern China were the driving forces behind the mid-late Holocene relative sea-level shift. The rise in relative sea level eventually led to the collapse of the Qingdun and Jiangzhuang sites in the Subei Basin. Our results provide independent vegetation evidence of the simultaneous changes in relative sea level and variations in climate.

Early Cretaceous palynofloras from the Bongor basin, Chad, and their palaeoenvironmental and palaeoclimatic significances

A systematic palynological investigation of borehole core and cutting materials enable the correlation of twenty-three wells in the Lower Cretaceous Bongor Basin, Chad. These borehole samples are dated as Early Cretaceous and three ascending palynological zones are recognized, the upper Hauterivian to lower Barremian Dicheiropollis Total Range Zone (I), the upper Barremian Sergipea–Zhonghuapollis Assemblage Zone (II), and the Aptian Afropollis–Pilosisporites–Ephedripites–Cicatricosisporites Assemblage Zone (III). A new species of gymnosperm pollen, Sergipea multipapillata sp. nov., is described from the palynoflora of the Bongor Basin. Regional stratigraphic correlation based on palynofloras of Lower Cretaceous is given between the Bongor Basin and its neighbouring area. In the Early Cretaceous the Bongor Area was an inland sedimentary basin, the changes in the palynoflora indicate changing patterns of vegetation, the palaeoclimate is reconstructed as mainly hot and arid, with seasonal precipitation and transient warm and humid breaks.

Spatio-temporal modeling of airborne pollen concentrations

Keywords: Pollen, Machine Learning, Allergic Disease Abstract Background and aim High concentrations of airborne pollen trigger seasonal allergies and possibly severe adverse respiratory and cardiovascular health events. Predicting pollen concentration accurately is valuable for epidemiological studies to determine the effects on cardiovascular, respiratory, and cognitive health. We aimed to develop a spatiotemporal land-use regression model for pollen, predicting daily concentrations at a fine spatial resolution of 1x1km across Switzerland between 2003 and 2020. Methods Daily pollen concentrations for hazel, alder, ash, birch, and grasses were available from 14 sites. We considered a range of spatial (elevation, tree type), temporal (date, season, month, week and day of the year, national daily pollen concentration) and spatiotemporal predictors (wind speed, wind direction, temperature, precipitation, relative humidity, satellite-observed Normalized Difference Vegetation Index (NDVI), and land-use (CLC, Landsat satellite) to explain variation in total pollen concentration for five specific pollen species. We applied a range of feature engineering techniques to encode categorical variables (land-use) and fill in missing values (Landsat). We applied a random forest model with 5-fold cross-validation. Results The median grass pollen concentration was 24 pollen/m3 (P5-P95 range 0-187 pollen/m3) during the main grass pollen season (May-July for all years). Preliminary results of a model predicting grass pollen concentration achieved an overall R2 of 0.74 and a root mean squared error (RMSE) of 24.12 pollen/m3 (cross-validation). Temperature, humidity, wind speed, NDVI, Landsat, average national daily pollen concentration and date features were the most important predictors for grass pollen concentration. Conclusions Building upon national observed pollen concentrations and using random forest machine learning, these spatiotemporal pollen models will serve to estimate individual residential pollen exposure. Resulting estimates will enable us to study respiratory and cardiovascular mortality and hospital admissions using historical data from the Swiss National Cohort and the Swiss Federal Office of Statistics.

Pollen collected by stingless bees Tetragonula laeviceps (Smith, 1857) (Hymenoptera: Apidae: Meliponini) from Central Sulawesi

The diversity of pollinating insects is used as conservation management. Pollen is gametophyte from male which can give characteristics to its offspring. The pollen carried by bees can be used as an identification of feed favored by bees. This study aims to identity pollen derived from the legs of stingless bees based on the color morphological characteristics of the pollen. The methods include color identification of pollen collected by stingless bees, pollen extraction, acetolysis, and pollen identification. Pollen with the same species at the study site has a color that is not much different. Stingless bees take pollen based on the size and distance of the plant to the hive. Smell and color as a secondary binder for stingless bees. Different plant pollen species can also be influenced by the protein requirements of each stingless bee colony. It can recognize the presence of flowering plants aroud the hive. The size of pollen can affect the bees in taking plant pollen.