Search

Despite the sudden burial to which they were subjected during the eruption of 79 AD, many of the soil samples from the Vesuvian area are poor or devoid of pollen. This research assesses whether a carbonization process may be responsible for the complete or partial loss of pollen grains or, at very least, for them going unrecorded during pollen analyses. The discovery of a certain number of pollen grains in plant material from Oplontis has made it possible to investigate which heating conditions they may have been subjected to. For this purpose, in this study, modern pollen grains were exposed to different temperatures for different time intervals in order to observe their modification. The data collected indicate that exposure to high temperatures, even for a short time, can significantly impact pollen grains to the point of making them undetectable during palynological analyses. Modern pollen grains similar to those of Oplontis are observed after exposure to 300 °C for 15 min. The state of preservation of the Oplontis reticulate grains makes prolonged exposure to 300 °C or higher temperatures unlikely. The temperature indications obtained are compatible with data from other studies. The hypothesis of combustion may also explain the small dimensions of many grains found in the Vesuvian sites. [ABSTRACT FROM AUTHOR]

The article compares two different methods of defining pollen seasons based on 10 years of birch and grass pollen data from Berlin, Germany, and Vienna, Austria. The study found that the European Academy of Allergy and Clinical Immunology (EAACI) definition correlated significantly with allergic rhinitis symptoms reported by users of electronic diaries. The analysis showed differences in the start, end, and duration of pollen seasons between the two cities, highlighting the importance of accurately defining pollen seasons for clinical trials and allergen immunotherapy. The study confirmed the applicability of both the EAACI and percentage analysis (PA) methods in describing pollen season characteristics for different regions. [Extracted from the article]

Benefiting from the rapid development of environmental DNA (eDNA) technologies, sedimentary DNA (sedDNA) emerges as a promising tool for monitoring plant compositions in remote regions. The Tibetan Plateau (TP), renowned for its harsh environment and numerous ponds and lakes, presents a potentially demanding region for the application of sedDNA on vegetation investigations. Here, we used the g and h universal primers for the P6 loop region of the chloroplast trnL (UAA) intron to amplify plant DNA in surface sediments from 59 ponds and small lakes on the southwestern TP. The applicability and limitations of using plant DNA metabarcoding for modern vegetation monitoring and palaeo-vegetation reconstructions have been assessed by comparing sedDNA, pollen, and vegetation survey data. Our results showed that plant DNA metabarcoding recorded 186 terrestrial taxa, of which 30.1% can be identified at the species level. The plant sedDNA approach can effectively disclose the dominant plant taxa (including Asteraceae, Cyperaceae and Poaceae) and significant vegetation assemblages in the vicinity of the investigated sites. The number of taxa and taxonomic resolution of plant sedDNA exceeded that of pollen analysis (75 taxa detected, 5.3% can be identified at species level). Unlike pollen that retains a broad spectrum of regional plant signals (including Pinus and Artemisia), plant sedDNA mirrors very local plants, underscoring its utility in local vegetation monitoring and reconstructions. To conclude, plant DNA metabarcoding of (small) lake sediments warrant increased attention in the future for local vegetation monitoring and reconstructions on the TP. [ABSTRACT FROM AUTHOR]

The Holocene infill of an intermittently open-closed barrier estuary (Painkalac Creek/Aireys Inlet) was examined on the southern margins of Australia, through aerial LiDAR, coring, sedimentology, radiocarbon dating and pollen analysis. It is found that almost all the accommodation space within the estuary has been occupied, with a thick sequence (>9 m) of sediments being deposited rapidly soon after flooding by the sea. The rate of sedimentation was 4.8 mm/year which closely matches the rate of sea level rise (4.5 mm/year) during the 1200 year period that the estuary infilled, from around 8000–6800 years ago. The evidence of estuarine deposition above the elevation of the modern intertidal zone provides significant further evidence for the presence of the mid-Holocene highstand sea level in this relatively unstudied part of the Australian coast. The pattern of infill departs from the traditional barrier evolution models. The first phase of infill was likely tide dominated with subtidal sand shoals being found landward of a subtidal bedrock sill. Once a beach-barrier sequence formed, the estuary infilled in a more traditional manner, with lateral progradation of a flood tide delta and central mud basin infill. The barrier estuary of Painkalac Creek therefore has undergone a complex evolutionary history, characterised by a change in process dominance from classic tidal to wave-dominated form. Infill occurred in a keep-up (or fast catch-up) mode, with geological control occurring in regard to the presence of an intertidal bedrock sill at the mouth of the estuary. [ABSTRACT FROM AUTHOR]

Pollen morphology and the reproductive biology of Calophyllum brasiliense were investigated in Parque Estadual das Fontes do Ipiranga, São Paulo, Brazil. The study encompassed pollen analyses using light, scanning, and transmission electron microscopy. Additionally, we collected data on reproductive biology, main visitors/pollinators, fruit set, and seed germination. The species exhibits individuals with perfect flowers (hermaphrodites) as well as male individuals with staminate and perfect flowers. Flowering occurs in October and November, and flowers have diurnal anthesis and pollen as a floral resource. Pollen grains are monads of medium size, isopolar, oblate-spheroidal to prolate-spheroidal, 3-(4)-zonocolporate, with exine fossulate-perforate with supratectal microechini. Hermaphrodite individuals have the highest proportion of malformed pollen due to their reduced grain size. The pollen grains from the hermaphrodite individuals displayed a low viability (0.06%), while those from male individuals had higher viability (66.38% and 55.78% for perfect and staminate flowers, respectively). The stigma was receptive throughout the anthesis period. Cross-pollination between perfect flowers of male and hermaphrodite individuals resulted in 8.80% success in fruit set, but led to the development of one abnormal seedling. Cross-pollination between staminate flowers and perfect flowers of hermaphrodite individuals showed a 7.70% success rate and the control group showed an 8.00% success rate, both groups leading to the development of normal seedlings. This tree species shows relatively low reproductive success and relies on pollinators (mainly Apis mellifera, Paratrigona subnuda, Tetragonisca angustula, and Halictidae sp. 1) for the setting of fruits and seeds. [ABSTRACT FROM AUTHOR]

This study discovers the distribution of vegetation in the Sougna Mountain and its modern pollen representation and investigates the relationships with environment and land use variables. A total of 31 moss polsters were collected between 138 and 1364 m above sea-level from wooded to open areas (e.g. cork oak forest, pine reforestation, and shrubland). At each sampling site land use and environment variables were collected. The vegetation in the Sougna Mountain is scattered in a mosaic along three vegetation belts which are displayed in distinct pollen assemblages dominated by the pollen equivalents of the vegetation types (Quercus suber forest, matorrals of Erica spp. and Cistus spp. and Pinus pinaster reforestation). The variation between the variables and pollen data was performed using CCA analysis. The anthropogenic variables such as grazing, and cultivation, contribute to discrimination of the degraded and grazed areas. High precipitation and altitude have a rather good correlation to wooded communities and consequently a good relation to the tree cover. Our results show that the pollen types of Poaceae, Cannabis, Plantago, Nicotiana, Asteraceae, and Urtica are related mostly to human practice and distinguish the disrupted communities. The presence of those taxa in the pollen diagram must be interpreted carefully. A high taxonomic resolution is recommended to prevent the overestimation of the abundance of some taxa. Our results contribute to the advancement of palynological reconstructions of past vegetation and land use in Sougna Mountain and generally in the Rif landscape. [ABSTRACT FROM AUTHOR]

AbstractAdesmia is the most species-rich genus in the informal Adesmia clade and temperate South America Leguminosae. The pollen morphology, ultrasculpture, and ultrastructure of 25 species of Adesmia were studied using light, scanning, and electron transmission microscopy to explore micromorphological data informative to the taxonomy of the genus. Additionally, a principal component analysis was performed to elucidate patterns of quantitative data variation among species concerning the most recent molecular data. We provide novel data about the genus, a comprehensive description of the pollen grains and sexine ultrasculpture, and descriptions of the exine ultrastructure. Furthermore, we suggest delimiting two pollen types based on the size of equatorial and polar axis dimensions to help in future palynotaxonomic studies and character optimisation focusing on pollen traits. [ABSTRACT FROM AUTHOR]

The article discusses a study conducted at Lake Tenndammen in Svalbard, focusing on the sedimentary units and pollen analysis. The lake is located in a biodiversity hotspot with a variety of plant species. The study involved radiocarbon dating and analysis of pollen types to understand the environmental changes over time. The findings suggest a correlation between human activities and changes in the pollen spectra, reflecting the industrial and post-industrial history of the region. [Extracted from the article]

Quantitative palynofloral analysis of late Berriasian to early Hauterivian aged sediments from the Vocontian Basin of southeast France has involved fifty-four outcrop samples from Vergol (Montbrun-les-Bains) and twenty-seven from La Charce (Serre de l'Âne). All samples were marls except for two from the early Valanginian Barrande layers, thin black layers rich in organic carbon. Sampling was focused particularly on the Berriasian/Valanginian, early/late Valanginian and Valanginian/Hauterivian boundaries with two of these particularly important as La Charce is the GSSP for base Hauterivian and Vergol is a GSSP candidate for base Valanginian. Although little has been previously published on the palynology of the Vocontian Basin, this study has benefitted from many previous multi-disciplinary studies in the area; the numerous palynofloral events recorded are tied closely to the standard ammonite zonation. Analyses were mainly focused on the dinocysts, but miospores have also been considered in terms of their palaeoenvironmental response, allowing broad assessment of relative sea level changes. Some linkage between peaks in coastal/lowland ratios, the d13C curve through the Weissert carbon isotope excursion (CIE) and the Muderongia group (possible reduced salinity) have been shown. A new dinocyst zonation scheme is proposed, involving twelve zones, eight of which cover the Valanginian; previous schemes are briefly discussed. Two genera, twenty-three species and five subspecies of stratigraphically-significant dinoflagellate cysts are described as new, two genera have been emended and thirteen new combinations have been proposed. The diagnosis of one acritarch genus has been emended and two new combinations effected. [ABSTRACT FROM AUTHOR]

• New palynological evidence of the Silves Group, Algarve Basin, Portugal is presented. • The Triassic-Jurassic boundary lies in the upper part of the Silves Group in the Silves Marl-Carbonate Evaporitic Complex, in the Loulé Rock Salt Mine. • Onslow microflora is recognized in the Silves Group, lower part of the Silves Marl-Carbonate Evaporitic Complex. This paper presents the results of palynostratigraphic studies in the Silves Group in the Algarve Basin, Portugal. From bottom to top comprises the Silves Sandstones, the Silves Marl-Carbonate Evaporitic Complex, and the Volcano-Sedimentary Series. This study aims to detail the age of the Silves Group, bracketing the Triassic-Jurassic transition, using palynology. For this purpose, 250 samples were collected from 14 main sections. Previous results from a section above the Variscan unconformity, enabled to date the base of the Silves Sandstones and the onset of the Mesozoic sedimentary cycle in the Algarve Basin to lower Carnian. In this work, the top of the Silves Sandstones, containing Camerosporites secatus , Enzonalasporites vigens , Granuloperculatipollis rudis , Lagenella martinii , Patinasporites densus , Samaropollenites speciosus , and Vallasporites ignacii , is dated to the upper Carnian. The base of the Silves Marl-Carbonate Evaporitic Complex, consisting of Alisporites sp., Araucariacites australis , Classopollis meyerianus , Classopollis torosus , Paracirculina quadruplicis and Triadispora sp., indicates an upper Carnian age. The presence of Alisporites diaphanus , Araucariacites australis , Cerebropollenites macroverrucosus, Classopollis meyerianus , Classopollis torosus , Perinopollenites elatoides , Calamospora mesozoica , and Kraeuselisporites reissingeri allows to date the top of the Silves Marl-Carbonate Evaporitic Complex as upper Rhaetian-lower Hettangian. This study allows to date the Silves Group in the Algarve Basin from the lower Carnian to lower Hettangian (Triassic-Jurassic boundary) for the first time. The Carnian microflora provides new insights of the Onslow Microflora in the Western Tethys. [ABSTRACT FROM AUTHOR]

The Poaceae family, one of the most diverse and widespread angiosperms, is prevalent in various natural and urban environments and is a major cause of allergies, affecting over 20% of the population in Europe, specifically in Ireland. With extensive grasslands, Ireland supports numerous grass species, though pollen release varies due to the family's complexity. The Hirst spore-trap is commonly used to sample airborne pollen, but the area of influence is debated and may differ by pollen type. This study compares grass pollen seasons between rural Carlow and urban Dublin, aiming to create forecast models for airborne pollen and identify key grass areas influencing the main pollen season (MPS). Two Hirst samplers were analyzed, using data up to 2020, and two threshold models (based on Swedish and Danish studies) were tested to find the best fit for Ireland. Airmass footprints were calculated using Hysplit and combined with grassland data to pinpoint major pollen sources. The results showed that Carlow had higher pollen concentrations but shorter seasons than Dublin. The Swedish threshold method was the most accurate for Ireland, with the Wicklow Mountains identified as a significant pollen source. These findings improve the understanding of pollen dynamics and support better public health and allergy management. [ABSTRACT FROM AUTHOR]

Commercially cultivated Prunus species are commonly grown in adjacent or mixed orchards and can be infected with unique or commonly shared viruses. Apple (Malus domestica), another member of the Rosacea and distantly related to Prunus, can share the same growing regions and common pathogens. Pollen can be a major route for virus transmission, and analysis of the pollen virome in tree fruit orchards can provide insights into these virus pathogen complexes from mixed production sites. Commercial honey bee (Apis mellifera) pollination is essential for improved fruit sets and yields in tree fruit production systems. To better understand the pollen-associated virome in tree fruits, metagenomics-based detection of plant viruses was employed on bee and pollen samples collected at four time points during the peak bloom period of apricot, cherry, peach, and apple trees at one orchard site. Twenty-one unique viruses were detected in samples collected during tree fruit blooms, including prune dwarf virus (PDV) and prunus necrotic ringspot virus (PNRSV) (Genus Ilarvirus, family Bromoviridae), Secoviridae family members tomato ringspot virus (genus Nepovirus), tobacco ringspot virus (genus Nepovirus), prunus virus F (genus Fabavirus), and Betaflexiviridae family member cherry virus A (CVA; genus Capillovirus). Viruses were also identified in composite leaf and flower samples to compare the pollen virome with the virome associated with vegetative tissues. At all four time points, a greater diversity of viruses was detected in the bee and pollen samples. Finally, the nucleotide sequence diversity of the coat protein regions of CVA, PDV, and PNRSV was profiled from this site, demonstrating a wide range of sequence diversity in pollen samples from this site. These results demonstrate the benefits of area-wide monitoring through bee pollination activities and provide new insights into the diversity of viruses in tree fruit pollination ecosystems. [ABSTRACT FROM AUTHOR]

Glacial periods have been considered as inhospitable environments that consist of treeless vegetation at higher latitudes. The fossil record suggests many species survived the Last Glacial Maximum within refugia, usually at lower latitudes. However, phylogeographic studies have given support to the existence of previously unknown high-latitude refugia that were not detected in the fossil record. Here, we test the hypothesis that cold-tolerant trees of Patagonia survived cold periods in microclimatically favourable locales where hybridization occurred between sister taxa. To study local presence through glacial periods in multiple refugia, we used pollen records and genetic information (isozymes, microsatellites, and combined nuclear and chloroplast DNA sequences) of population pairs of Nothofagus antarctica and N. pumilio that belong to the ancient subgenus Nothofagus which can potentially hybridize in nature, along their entire latitudinal range in Patagonia. Studied species share the N. dombeyi type pollen, which was abundant at >20% in the northernmost latitudinal bands (35–43°S), even during the Last Glacial Maximum. Mid- and southern latitudinal records (44–55°S) yielded lower abundances of ~10% that increased after c. 15.0 cal. ka BP. Therefore, fossil pollen evidence suggests a long-lasting local presence of Nothofagus throughout glacial–interglacial cycles but mostly as small populations between 44°S and 51°S. We found species-specific and shared genetic variants, the latter of which attained relatively high frequencies, thus providing evidence of ancestral polymorphisms. Populations of each species were similarly diverse, suggesting survival throughout the latitudinal range. Estimates of coalescent divergence times were broadly synchronous across latitudes, suggesting that regional climates similarly affected populations and species that hybridized through climate cycles, fostering local persistence. Graphical Abstract [ABSTRACT FROM AUTHOR]

Gene flow affects the genetic diversity and structure of tree species and can be influenced by stress related to changing climatic conditions. The study of tree species planted in locations outside their natural range, such as arboreta or botanical gardens, allows us to analyse the effect of severe fragmentation on patterns and distances of gene flow. Paternity analysis based on microsatellite marker genotyping was used to analyse how fragmentation affects gene flow among individuals of Quercus rubra L. distributed in a small isolated group of trees (15 trees) planted in the arboretum on the North Campus of the University of Göttingen. For paternity analysis, 365 seedlings from four seed parents were selected and genotyped using 16 microsatellites. The analysis revealed the majority of pollen (84.89%) originated from trees within the site and identified three large full-sib families consisting of 145, 63 and 51 full-sibs. The average pollen dispersal distance for the four seed parents ranged from 17.3 to 103.6 meters. We observed substantial genetic differentiation among effective pollen clouds of the four seed parents (G"ST = 0.407) as a result of cross pollination between neighboring trees. No self-fertilization was observed. Gene dispersal via pollen followed the expected distance-dependent pattern, and we observed a significant influx of external pollen (15.11%, ranging from 8.64 to 26.26% for individual seed parents) from a diverse set of donors (30). Long-distance pollen dispersal could explain the presence of significant genetic variation even in isolated natural Q. rubra populations. [ABSTRACT FROM AUTHOR]

The new species, Paepalanthus fonsecae (Eriocaulaceae), is described and illustrated. It is placed in P. sect. Conodiscus due to its dimerous flowers, subcylindrical receptacles, and a gynoecium with the nectariferous branches of the style inserted below the level of the short stigmas on the fused portion of the style. The new species is compared with similar congeners, especially P. echinoides, from which it is mainly distinguished by having an elongated aerial stem covered by membranaceous and flat leaves, and the inflorescences consisting of usually fewer but longer scapes, each subtending a wider capitulum with elliptic involucral bracts. Paepalanthus fonsecae is known from two collections from central Brazil in the municipalities of Alto Paraíso de Goiás and Cavalcante and, according to IUCN criterion B, it should be treated as critically endangered (CR). Detailed comments on the species' distribution and morphology, along with new anatomical and palynological data, are provided. [ABSTRACT FROM AUTHOR]

The present investigation breaks new ground by examining the Raniganj sediments in the Kendudihi section of the Ib‐River Coalfield, Odisha, India. The study identifies a megaflora consisting of 25 species of Glossopteris, Vertebraria indica, stem casts and equisetaceous stems. The microflora is predominantly composed of Striatopodocarpites spp., with a secondary presence of Densipollenites spp. The lithological signatures, including off‐white fine‐grained sandstone with thin bands of silty shale and grey shale, indicate that these sediments belong to the Late Permian succession of the Lower Gondwana sequence, specifically the Raniganj Formation. The macrofloral assemblage found in the lowermost grey shale can be attributed to the Wordian–Capitanian age, while the microfloral assemblage in the upper silty shale resembles that of the Wuchiapingian‐Changhsingian age. Well‐preserved palynomorphs and megafossils, along with the abundant occurrence of lath‐shaped translucent phytoclasts in the grey and silty shale of the Raniganj sediments exposed in the Kendudihi section, explicitly suggest that the sediments were deposited in proximal, low‐energy swampy settings. Additionally, the moderate occurrence of charcoal (20%), along with the existence of degraded organic matter (DOM: 7.6%) and amorphous organic matter (AOM: 16.4%), indicates that the sediments might have been deposited in oxic–dysoxic conditions. The palynological and megafloral studies reveal a warm‐temperate climate with low humidity and intermittent spells of hot and cold seasons, associated with abundant rainfall. The occurrence of phosphorite in the form of nodules and thin lenses, as well as biogenic structures at the juncture of the Raniganj and Barren Measures formations, suggests a marine incursion in the area during the deposition of the late Barren Measures and early Raniganj sediments. X‐ray diffraction (XRD) analysis identified fluorapatite (Ca5(PO4)3F) as the predominant phosphatic mineral phase in the phosphatic nodule, siltstone and claystone. The Post‐Archean Australian Shale composition, normalized rare earth element (REE) patterns of samples from this area, reveals slight positive La (average La anomaly: 1.02) and Gd (average Gd anomaly: 1.05) anomalies and heavy REE enrichment compared to light REE, explicitly indicating a marine environment. [ABSTRACT FROM AUTHOR]

• Pollen analysis is vital to determine the geographical and botanical origins of honey. • The pollen percentage is used to distinguish honey as monofloral or multifloral. • The dominant pollen source is identified. • Twenty five percent of the samples exhibited a high diversity index. Melissopalynology plays a pivotal role in identifying and managing the geographical and botanical origins of honey. In this study, forty-five honey samples were collected from three potential districts in the North Wollo zone, Ethiopia. The pollen grains of these samples were analyzed using the procedures outlined by the International Commission for Bee Botany (ICBB) to determine the botanical sources of the honey. Among the samples, twenty-five were classified as monofloral, while the remaining twenty were identified as multifloral honey. Nineteen plant species from twelve different plant families were identified as the honey bee floras in the North Wollo zone. The dominant families, representing over 45% of the pollen grains in the samples, were Asteraceae (9 samples), Myrtaceae (5 samples), Papilionaceae (4 samples), Fabaceae (2 samples), Hypericaceae (2 samples), Acanthaceae (1 sample), Brassicaceae (1 sample), and Ericaceae (1 sample). Bidens spp., Trifolium rueppellianum, and Eucalyptus globulus emerged as the top three honey bee floras in terms of relative percentage and frequency. Furthermore, eleven samples exhibited a high diversity index range (H) of 1.56% in Lasta and 1.01% in the Meket districts, while the remaining thirty-four samples showed a lower diversity index ranging from 0.31 to 0.99. Our findings underscore the importance of conserving bee floras to enhance honey production and ensure sustainability in beekeeping practices in the North Wollo Zone. [ABSTRACT FROM AUTHOR]

Fire is an essential component of the landscapes and forests of the Pacific Northwest, including the temperate rainforests of the Olympic Peninsula. Previous fire history reconstructions from the peninsula show that fire return intervals varied throughout the postglacial period, primarily in response to climatic changes and corresponding shifts in vegetation. However, much less is known about the fire history of the low-elevation forests of the Olympic Peninsula and the role of cultural fire regimes in these environments. The purpose of this study was to reconstruct the paleoenvironmental history of a low-elevation study site, Beaver Lake, located in the northwestern part of the peninsula. Using macroscopic charcoal, pollen, and sedimentological analyses of a ca. 3440-year-long record, we reconstructed a high-resolution record that shows fire activity was remarkably high during the late Holocene for an area considered part of a temperate rainforest. However, patterns of burning varied throughout the record, with the first third (ca. 3440 to 2350 cal yr BP) and last third (ca. 800 cal yr BP to the present day) recording much higher amounts of fire activity compared to the middle portion (ca. 2350 to 800 cal yr BP), which recorded very little fire activity. Larger and/or more severe fires that likely burned during multi-year droughts correlate with peaks in magnetic susceptibility and pollen trends that indicate substantial geomorphic responses and successional changes in forest structure following these events. Cooler temperatures and a wetter climate, indicated by nearby glacial advancements, may have staved off fire activity during the period of low fire activity. Cultural burning by the Indigenous tribes of the Olympic Peninsula likely contributed to the observed fire activity at Beaver Lake as nearby prairies were managed for resource procurement, indicated in particular by an increase in herbaceous morphotype charcoal during the past 800 years. [ABSTRACT FROM AUTHOR]

Background and aims: Pteris is widely distributed with ca. 65 species in the Tropics. In Brazil, 24 species were recognized and five of them are endemic to the Atlantic Forest. The objective of the present paper is to re-evaluate the taxonomy of Pteris occurring in Brazil, based on new morphological evidence of old and recent specimens deposited in herbaria, analysis of types, and observations in the field. M&M: The new approaches are based on morphological data such as SEM images of the spores and from the examination of herbarium collections mainly from SP and RB Herbaria. Results: Four species are being recognized in the present paper (P. lata, P. organensis, P. praealta, and P. sericea). For two of them, two new combinations into Pteris are presented: P. organensis and P. praealta. A key to distinguishing the newly recognized species and its relative taxa, as well as descriptions, illustrations, and comments are presented in this paper. Conclusions: By reviewing herbarium materials, mainly observing the morphology of the spores, and collecting more specimens in the field, it was possible to recognize three species (Pteris lata, P. organensis, and P. praealta) in Brazil and also verify the correct application of the name Pteris sericea to the Brazilian plants. All these names had been previously synonymized in previous studies. After this study, 27 species of Pteris are recognized in Brazil. [ABSTRACT FROM AUTHOR]

The value of deep‐water sedimentary successions as reliable records of environmental change has been questioned due to their long response times and sediment pathways leading to complex responses to climatic change and tectonic signals over differing timescales. We studied the Gulf of Corinth, Greece, to test the value of deep‐water stratigraphic successions as records of external controls on sediment flux in a setting with short response times and transport distances. The confinement of the rift basin allows for a near‐complete accounting of clastic sediment volumes. The recent acquisition of high‐resolution seismic reflection data, utilisation of International Ocean Discovery Programme Expedition 381 cores and a robust chronological framework, enable evaluation of the stratigraphy at a high temporal resolution. Combining borehole and high‐resolution seismic reflection data, distinct seismic units can be correlated to multiple paleoenvironmental proxies, permitting quantification of sediment flux variation across successive glacial–interglacial cycles at ca. 10 kyr temporal resolution. Trends in average sediment flux since ca. 242 ka show ca. 2–9 times greater sediment flux in cooler glacials compared to warmer interglacial conditions. The Holocene is an exception to low sediment flux for the interglacials, with ca. 5 times higher rates than previous interglacials. The short and steep configuration of the Sythas canyon and its fan at the base of an active submarine normal fault results in deep‐sea deposition at all sea‐level stands. In contrast, adjacent canyon systems shut down during warm intervals. When combined with palynology, results show that periods of distinct vegetation re‐organisation correlate to sediment flux changes. The temporal correlation of sediment flux to palynology in the Gulf of Corinth over the last ca. 242 kyr is evidence that variability of sediment supply is largely governed by climate‐related changes in hinterland catchments, with sea‐level and tectonics being second‐order controls on sediment flux variability. [ABSTRACT FROM AUTHOR]

This study was intended to determine the melissopalynological characteristics, LAB color, browning index, total phenolic content, antioxidant activity, phenolic profile, and their correlations within Iranian honeys. Ten honey samples were collected from beekeepers in various floristic regions of Iran, along with two commercial multi-floral samples. To determine the antioxidant activity, three methods of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, β-carotene bleaching, and Ferric reducing/antioxidant power (FRAP) were used. Phenolic compounds were analyzed by high-performance liquid chromatography with diode-array detection (HPLC–DAD). Pollen analysis revealed that bees primarily fed on the Fabaceae and Asteraceae families in the Iranian flora. The local samples were taxonomically categorized as multi-floral honey. Besides, the commercial samples demonstrated the lowest levels of total phenolics and relatively poor antioxidant activity across all three methods. Syringic acid and luteolin were the predominant phenolic compounds in all samples. A strong correlation (p < 0.01) was found between color, melanoidin content and antioxidant activity, while no significant correlation existed between phenolic content and antioxidant activity. Overall, the results confirmed that examined multi-floral honeys exhibited inferior antioxidant activity compared to studies conducted in other regions worldwide, possibly due to sugar-fed bees, insufficient levels of potent phenolic constituents, and post-harvest thermal treatments. [ABSTRACT FROM AUTHOR]

The paper presents a new section of the late Palaeocene‐early Eocene, palynological assemblages and stable carbon isotopes from the Lakadong sandstone member of the East Khasi Hills of Meghalaya (India). The Palaeocene‐Eocene transition (PET) is marked by stratigraphic markers of dinoflagellate cysts (taxa of Apectodinium augustum, now Axiodinium augustum) and negative carbon isotope excursion. The palynofloral assemblage indicates the sequence represents warm, humid tropical to subtropical conditions with heavy rainfall. The depositional environment of the Lakadong Sandstone Member is interpreted to be neritic. The new insights of this study in this section suggest the PET with the occurrence of Apectodinium acme consisting of A. augustum at CS5‐15a. [ABSTRACT FROM AUTHOR]

This article explores the molecular mechanisms underlying pollen tube growth in pear trees. The researchers focused on the role of flavonoids, a group of plant secondary metabolites, in regulating pollen development and growth. They identified a specific gene, PbrF3H, that is involved in flavonoid biosynthesis and found that it is regulated by a transcription factor called PbrMYB186. Knockdown experiments showed that both PbrF3H and PbrMYB186 are essential for flavonoid production and pollen tube growth. The study provides insights into the regulatory network of flavonoids in pear pollen tubes. [Extracted from the article]

The widespread use of pollen analysis in various fields in Indonesia is hampered mainly by the application of pro-analyst chemicals in standard pollen preparation. To solve this problem, a new pollen preparation technique using technical chemicals was developed. The results of comparison between this new technique with the standard technique used before showed that the pollen-spore yields, the quality of pollen slides, and the slide visibility resulted from both techniques is comparable. Furthermore, the new technique reduced the chemical cost of the standard technique by IDR. 87,125.00 per sample. [ABSTRACT FROM AUTHOR]

Strong aggradational tendencies during the late Pleni-Weichselian have been noted in river valleys in central Europe. Thick series of mineral deposits were laid down, but also organic or mineral-organic horizons were formed under favourable conditions. The study area is located in the central section of the valley of the River Warta within an extraglacial area of the last glaciation. At the Warenka site alluvia, that attain thicknesses of 16 m, were analysed. Lithofacies analysis, OSL dating of mineral sediments and radiocarbon dating of organic and mineral-organic strata were performed. Organic and mineral-organic deposits were also subjected to pollen and Cladocera analyses. Together this set of analyses was used to determine fluvial processes and environmental conditions during the late Pleni-Weichselian. The results obtained allow the conclusion that these levels were deposited in the sedimentary environment of a low-energy, sand-bed braided river, which operated in the period from approximately 30 to 24 cal kBP – the late Pleni-Weichselian. During this time, there were periods when shallow water bodies were formed on the valley bottom, where deposition of organic material was possible. The presence of this type of sediment made it possible to reconstruct the vegetation cover; this had the character of a steppe-tundra, periodically shrubby steppe-tundra. Short-lived reservoirs were characterised by shallow-water settings with weakly developed vegetation and temporary influence of floodwaters as indicated by changes in cladoceran assemblages. Pollen spectra, low concentration of cladocerans, as well as the presence of the cold-tolerant Cladocera taxa are indicative of cold climatic conditions. [ABSTRACT FROM AUTHOR]

This study employed scanning electron microscopy to investigate the pollen morphology of Taiwanese Asparagaceae species, revealing that their pollen morphology closely aligns with that of other monocotyledonous plant taxa such as Asparagales, Commelinales, and Bromeliales. Despite the overall similarity, variations in pollen morphology across different genera were noted, highlighting its potential utility in classification. Unlike the wide diversity observed in flower morphology, Asparagaceae pollen morphology appears conservative, rendering it less effective as a taxonomic marker at the species level. The study also delved into the effects of pollenkitt and harmomegathy on pollen morphology, discovering that pollenkitt partially or completely coats the pollen surface, potentially complicating the identification of exine sculpture. Furthermore, the harmomegathic effect was observed to influence aperture dynamics. Consequently, observing both hydrated and dried pollen is advisable, as it can more accurately depict the pollen's aperture morphology and offer additional insights for pollen grain analysis. [ABSTRACT FROM AUTHOR]

Huberia DC. is a genus belonging to the family Melastomataceae, which comprises 37 species distributed in vegetation formations of the Amazon Forest and Andes complex and the Atlantic Forest biome. Recent phylogenetic studies have modified the circumscription of the genus to include the genera Behuria Cham. and Dolichoura Brade. Furthermore, the genus was placed in the new tribe Cambessedesieae, together with the genera Cambessedesia DC. and Merianthera Kuhlm. In view of the relevant contribution of palynology to taxonomic and phylogenetic studies, this study aimed to expand the palynological knowledge of Huberia. Samples from 22 species were obtained from specimens deposited in the herbaria of the Rio de Janeiro Botanical Garden (RB), National Museum/UFRJ (R), Municipal Botanical Museum of Curitiba (MBM), and Federal University of Paraná (UPCB). Flower buds were acetolysed and used to prepare pollen sediment slides. Slides were mounted with glycerinated gelatin and analyzed and photographed under a light microscope. The results showed pollen grains in monads, small, varying in shape from prolate-spheroidal to subprolate; heteroaperturate (colporate and pseudocolpate), tricolporate, with a small, very small, or non-existent polar area in syncolporate pollen; colpi long or very long and narrow, endoaperture lalongate with median constriction in most species and lolongate in others; exine perforate, rugulate, or striate microreticulate and the sexine thicker than the nexine. Based on the findings of this study, it is concluded that palynological characters provide information for the taxonomy of the group. [ABSTRACT FROM AUTHOR]

Passifloreae is the largest tribe of the family Passifloraceae sensu stricto. Within the tribe, palynological studies are mostly restricted to the largest genus, Passiflora, given its large number of species, ca. 500 taxa. Consequently, other genera within the tribe are frequently underexplored, particularly in terms of pollen characters. Given the importance of pollen morphology for the taxonomic classification of Passifloraceae s.s., it is necessary to describe the pollen characters of Basananthe Peyr., Deidamia Noronha ex Thouars, and Efulensia C.H.Wright. The characters analyzed here include dispersion unit, polarity, size, shape, aperture number, aperture type, operculum type, and sexine ornamentation. Subsequently, 10 metric variables were subjected to principal component analysis. The results show that the studied genera could be easily distinguished based on pollen characters, confirming the importance of palynology. The pollen of all studied species, regardless of the genus, had the same aperture number and type, namely 3-colporate. Sexine ornamentation ranged from microreticulate to reticulate, without spines. Here, pollen characters of Basananthe, Deidamia, and Efulensia are compared with those of closely related genera and Passiflora, contributing to a more comprehensive and up-to-date understanding of the group. The results confirm the importance of analyzing pollen attributes for the taxonomy of Passiflora s.s. [ABSTRACT FROM AUTHOR]

Core samples from four boreholes (SAV-1, SAV-117, SAV-124, SAV-125) within the Vaddugudem block of the Godavari Valley Coalfield, Southern India have been palynologically investigated to understand the stratigraphic setting of that area. Only 60 out of the 172 samples yielded identifiable palynoassemblages. From the observed palynofloral composition, five distinct palynoassemblages (Scheuringipollenites Assemblage: PA-I, Striatopodocarpites + Faunipollenites Assemblage: PA-II, Striates + Striasulcites Assemblage: PA-III, Striates + Guttulapollenites Assemblage: PA-IV, Lundbladispora + Verrucosisporites Assemblage: PA-V) were identified. Furthermore, five distinct palynozones (Scheuringipollenites barakarensis Zone = PZ-1, Striatopodocarpites + Faunipollenites Zone = PZ-2, Gondisporites raniganjensis Zone = PZ-3, Guttulapollenites gondwanensis-Striatopodocatpites tiwarii Zone = PZ-4 and Playfordiaspora cancellosa Zone = PZ-5) were identified. These correspond to the Artinskian (PZ-1), Wordian–Capitanian (PZ-2 and PZ-3), Wuchiapingian–Changhsingian (PZ-4) and Induan–Olenekian (PZ-5), respectively. The study site is situated within a geologically active region within the basin, primarily attributed to the exposure of elevated basement rocks on the eastern side of the borehole locations. Notably, the palynozones appear as relatively narrow layers in the boreholes investigated within this tectonically disturbed basin. The repetition of palynoassemblages and palynozones at small intervals suggests that the boreholes are located in a fault zone with multiple fault planes and that palynomorphs were reworked along these fault planes. Fault slices of different lithological units containing palynoassemblages may have intersected the boreholes. Specifically, the recurrence of thin marker palynoassemblages and palynozones, which show similarities in age to the Barakar and Lower Kamthi/Raniganj formations, is likely attributable to tectonic disturbances, such as faulting. This disturbance may have induced the reworking or migration of palynomorphs along the fault plane. As a result, it is concluded that variations in the stratigraphic abundance of these reworked palynomorphs can serve as indicators of tectonic settings, even when these settings are not readily discernible in the geological record. [ABSTRACT FROM AUTHOR]

Here we present the palynological composition of a single sample of the elusive purple honey collected in southern North Carolina and discuss how it fits within a nearby statewide South Carolina melissopalynological study. 302 samples were collected by nineteen beekeepers participating in this year-long project, submitting honey samples while honeybees were actively collecting nectar. The absence of pollen of Pueraria (kudzu) in the purple honey dismisses the often-suggested link between the unique tint of the purple honey and kudzu's purple pollen. A second hypothesis hinting that the tint could be linked to ripened berries is not reinforced by our investigation as pollen of Ericaceae (eg blueberries) and Rosaceae (eg blackberries) were not found in the purple honey sample but were commonly found in classic golden honey analyzed. The presence of Vitis pollen supports the possibility that bees forage on wild muscadine grapes (Vitis rotundifolia) which was available in the foraging area. This study cannot discredit the possibility that bees were foraging on berry juices or other sugar sources containing purple pigments because these sources contain little or no pollen. A third hypothesis proposes a link between purple honey and the sourwood tree, Oxydendrum arboretum. This hypothesis is supported by this investigation as the dominant pollen type recovered in the purple honey was sourwood, with 19% in relative abundance, a significant percentage for this plant. We suggest chemical analysis of purple honey samples be conducted to determine if berry juice or sourwood is the more likely source of the pigmentation. [ABSTRACT FROM AUTHOR]

Research on the food sources used by bees in agricultural landscapes is crucial to promote pollinator conservation measures in and around cultivated areas. This investigation aims to identify and quantify the pollen resources exploited by Schwarziana quadripunctata (Lepeletier 1836), assessing the trophic niche of this bee in agricultural areas with coffee plantations. Pollen analysis was conducted based on the pollen load of the corbiculae of 70 bees, sampled during the flowering period of two species of coffee trees in commercial plantations located in Rio de Janeiro, Minas Gerais and Espírito Santo states, Brazil, in 2019 and 2021. A total of 78 pollen types from 23 botanical families were identified, with Coffea arabica and Coffea canephora comprising 92% of the samples. Cestrum sp. (2.3% – Solanaceae), Fabaceae sp. 1 (0.9%), Solanum sp. (0.75% – Solanaceae) and Chamaecrista sp. (0.71% – Fabaceae) were the next most prevalent. The dominance of the coffee tree pollen confirms the floral constancy of S. quadripunctata during periods of intense flowering. Excluding coffee pollen, the most represented families were Solanaceae (46.6% of the samples), Fabaceae (27.5%), Rubiaceae (8.51%), and Meliaceae (2.53%). The findings reveal that S. quadripunctata actively forages from sources other than coffee, even during the intense flowering of these plants, highlighting the importance of floral resources in the proximity of plantations. The use of pollen sources beyond the coffee tree highlights the importance of conserving nearby forest fragments and maintaining a diverse array of plants surrounding coffee trees even during coffee flowering. [ABSTRACT FROM AUTHOR]

Pollen, fruit, and seed morphology of the Cistus species (Cistaceae) from Turkey were investigated by light microscopy (LM) and scanning electron microscopy (SEM) to describe their characteristics and to clarify the diagnostic importance of these properties for taxonomical purposes. The pollen grains are oblate-spheroidal, with the polar axis ranging from 32 to 55 μm, and the equatorial axis ranging from 34.25 to 57 μm. Microreticulate-rugulate, striato-reticulate, microechinate, and microreticulate with smooth supratectal elements were found on exine sculpturing. The fruits are ovoid, oblong-globose, or ovoid-globose, and their size ranges between 3–11.2 mm in length and 2.9–10.3 mm in width. Capsule surface patterns can be divided into three types, namely irregularly reticulate, striate, and reticulate-areolate. The hairs on the capsule show variation in type: pilose, bifurcate, and stellate. The seeds are polyhedral, ovoid, rhomboid, oblong, or tetrahedral, and their color varies between dark brown, reddish-brown, yellowish-brown, and black. Four seed coat ornamentation types were observed: reticulate-ruminate, reticulate-rugose, colliculate-ruminate, and alveolate-rugose. Cluster analysis and principal component analysis revealed that the pollen dimension, exine sculpturing, capsule size, capsule indumentum type, capsule surface pattern, seed color, and seed coat ornamentation are the most significant variables to differentiate the Cistus species studied. [ABSTRACT FROM AUTHOR]

Changing climatic conditions is a perpetual circumstance for mankind. In this study, we investigate local environmental and climatic changes near Kangerlussuaq, west Greenland. Our reconstruction is based on a lake sediment core and methods include chemical proxies and a palynological analysis. The investigated site is located 15 km from the Aasivissuit Inuit summer hunting ground, which has been in use for caribou hunting for more than 2000 years. The presented climatic reconstruction covers the time from c. 560 CE to present time. We identify three distinct periods of climate regimes: From c. 560–1100 CE conditions were stable, warm and humid, and summer temperatures were 1.5–2°C warmer than today. 1100–1600 was a period of cooler and very arid conditions with more sea ice, corresponding to the Neoglacial cooling. In this period, we detect two wildfire events and subsequent temporary caribou abandonment of the area. From 1600 to present we find increasingly warmer conditions with more precipitation and less extensive sea ice cover, gradually approaching today's climate regime in Kangerlussuaq. We review the existing literature regarding the Aasivissuit summer hunting ground, which was first used concurrently with the detected cooling. Despite climatic deterioration, the hunting ground was regularly in use throughout the Neoglacial and onwards, with peak hunting intensity in the early 1700s. The detected wildfires and reindeer abandonment are interpreted to be localized events at the coring site and did not affect the hunting ground. Our findings highlight the resilience of the Inuit hunters to climatic changes as well as the advantages and limitations of local environmental reconstructions. [ABSTRACT FROM AUTHOR]

We present a multiproxy analysis of a sediment core from Freshwater Pond, Barbuda, one of just a few inland paleoenvironmental records from the Lesser Antilles. Our results shed light on the relative contributions of climate variability and Pre- and Post-Columbian human activities to vegetation and fire dynamics on Barbuda. The presence of macroscopic charcoal and pollen of ethnobotanically-useful and disturbance-indicator plant taxa in the sediment record suggests that Pre-Columbian subsistence activities occurred within a few kilometers of the pond between ~150 BCE and ~1250 CE. Our record extends anthropogenic fires back into the early Ceramic (500 BCE–1500 CE) and possibly late Archaic Ages (3000–500 BCE) adding evidence to the timing of arrival of the island's earliest inhabitants. The history of island-wide biomass burning inferred from microscopic charcoal fragments showed heightened fire activity between ~540 and ~1610 CE followed by a period of quiescence that reflected the transition from Pre- to Post-Columbian land-use practices associated with European colonization of the region. The British established a permanent settlement on Barbuda in the 1660s, but given Barbuda's unsuitability for large-scale agriculture, timber harvesting, small-scale farming, and livestock rearing, activities that left no detectable charcoal footprints likely dominated post-colonial land use. The lack of any clear correspondence between the reconstructed histories of fire and effective moisture at Freshwater Pond supports the idea that Late-Holocene fire activity on Barbuda was driven primarily by human activity. [ABSTRACT FROM AUTHOR]

Herbaria are vital resources of biodiversity education and conservation. They contain significant dried collections and botanical data of plant species that are useful for taxonomy, systematics, and plant-based applied research applications. Verbascum L. is the largest genus within the Scrophulariaceae family globally. However, the high morphological diversity within the genus poses significant challenges for accurate species delimitation. This study investigated the pollen and seed morphology of seven distinct Verbascum groups (comprising 10 taxa, including three endemics) from southeastern Anatolia using scanning electron microscopy (SEM). SEM analyses revealed that all examined taxa possessed tricolporate pollen apertures, with pollen shapes varying between prolate spheroidal and oblate spheroidal. Seeds exhibited a light brown to dark brown color, with a prismatic oblong shape and alveolate surface. The seed coat ornamentation consisted of irregular polygonal cells, densely covered with distinct vesicles. Findings demonstrate significant morphological distinctions in both pollen and seed characteristics, suggesting their utility in taxonomic discrimination within Verbascum groups. Notably, the detailed micromorphology revealed by SEM proved to be particularly valuable for classifying these taxa. These results contribute the understanding of the taxonomic diversity within Verbascum and highlight the crucial role of SEM in uncovering microstructural details for accurate species identification. [ABSTRACT FROM AUTHOR]

Background: The systematic status of sect. Tuberculata and its taxonomy have recently attracted considerable attention. However, the different bases for defining the characteristics of sect. Tuberculata has led to many disagreements among the plants in this group. Camellia neriifolia and Camellia ilicifolia have been the subject of taxonomic controversy and have been treated as different species or varieties of the same species. Therefore, it is important to use multiple methods, i.e., integrative taxonomy, to determine the taxonomic status of C. neriifolia and C. ilicifolia. This is the first study to systematically explore the taxonomic position of these two plants on the basis of Morphology, Anatomy, Palynology and Molecular Systematics. Results: Extensive specimen reviews and field surveys showed that many differences exist in C. neriifolia and C. ilicifolia, such as the number of trunk (heavily debarked vs. slightly peeling), leaf type (smooth thin leathery, shiny vs. smooth leathery, obscure or slightly shiny), leaf margin (entire vs. serrate), flower type (subsessile vs. sessile), number of styles (3–4 vs. 3), and sepal (ovate vs. round). Moreover, C. neriifolia has a more distinctive faint yellow flower color, and trunk molting was more severe in C. neriifolia than that in C. ilicifolia. In addition, micromorphological analysis of the leaf epidermis showed that the two species differed in the anticlinal wall, stomatal apparatus, and stomatal cluster, and pollen morphology analyses based on pollen size, germination furrow, and polar and equatorial axes showed that they are both distinct from each other. The results of the phylogenetic tree constructed based on the whole chloroplast genome, protein-coding genes, and ITS2 showed that both C. ilicifolia and C. neriifolia were clustered in different branches and gained high support. Conclusions: The results combine morphology, anatomy, palynology, and molecular systematics to treat both C. neriifolia and C. ilicifolia as separate species in the sect. Tuberculata, and the species names continue to be used as they were previously. In conclusion, clarifying the taxonomic status of C. neriifolia and C. ilicifolia deepens our understanding of the systematic classification of sect. Tuberculata. [ABSTRACT FROM AUTHOR]

A palynological study of 84 cutting samples from Cape Three Points 1 (CTP-1) well in the Tano basin allows the identification of three biozones based on the First Appearance Datum (FAD) and Last Appearance Datum (LAD) of stratigraphically significant sporomorphs taxa recovery. These are Elateropollenites jardinei - Reyrea polymorphus Zone, Elaterocolpites castelainii - Afropollis jardinus Zone, and Cretacaeiporites polygonalis - Classopollis classoides Zone, which permit an age assignment of early - middle Albian, late Albian - early Cenomanian and late Cenomanian respectively. The diagnostic miospores from the samples are characteristic of the Albian-Cenomanian Elaterate paleofloral Province in a semi-arid to arid climate, with sediments yielding mixed kerogen assemblage which reflects a marginal marine or nearshore environment. Four palynofacies assemblages (P-1 to P-4) and kerogen types identified indicate deposition under marginal dysoxic-anoxic basin (kerogen type III), shelf to basin transition (kerogen type III/II), a distal suboxic-anoxic basin (kerogen type II>I) and distal dysoxic-anoxic shelf (kerogen type II) conditions respectively. Thermal maturity values obtained from colour changes of psilate spore (Deltoidspora, Cyathidites) reveal that samples from P-1 and P-2 are within immature phase and P-3 and P-4 are mature. [ABSTRACT FROM AUTHOR]

Declines in pollinating insects have been linked to changes in land cover, affecting the availability of nesting sites and floral resources. Our study is the first analysis of changes in pollen load composition of 2 mining bees, Andrena barbilabris (Kirby) and Andrena flavipes (Panzer) (Hymenoptera: Andrenidae), at the same sites in central England, over 75 years. This provides a unique opportunity to remove spatial variation and review temporal changes in pollen diet within the context of landscape change. We analyzed modern-day pollen load composition for these species and compared it with historical data from the same sites. We then examined potential links between land-use change and the bees' diets. Both bees showed dietary flexibility and lower diet breadth for A. barbilabris , and the bees' foraging strategies appear to have changed. Andrena flavipes collected more pollen taxa in a single load, while A. barbilabris appeared to source pollen from greater distances. Landscape changes at the studied sites have affected the nutritional environment for these bees. Our findings are supported by an existing assessment of floral resources, which found floral diversity has decreased overall in both the habitats used by these bees. However, more research is needed on the nutritional content of pollens used by these bees, both now and historically, to estimate how pollen diversity has changed. The bee's-eye view underlines the importance of understanding how species respond to local changes so that effective conservation strategies can be developed. [ABSTRACT FROM AUTHOR]

Eleven Terminalia species growing in streets and gardens in Cairo (Egypt) were investigated for their pollen morphology. The study's objectives were to explore the variation among Terminalia species' pollen pheno-characters and to categorize the various species within this genus according to these pollen characteristics. The results showed that there are significant variations in the pollen morphological characteristics in the genus under study, and as a result, these traits can be regarded as eurypalynous. Each of the two main categories of Terminalia species mono-morphic and di-morphic includes various pollen morphologies, ranging from spheroidal to prolate with hexa-aperture that may be similar or of two types. For each of the eleven species, an identification key and a clustering phenogram for the fifteen major pollen features have been created. The aperture type, aperture similarity, and exine ornamentation are some of the crucial traits for the differentiation of the species examined while the pollen shape class has a poor diagnostic character. According to the unique characteristics of the pollen morphology of the Terminalia species, three groups and two subgroups were identified. [ABSTRACT FROM AUTHOR]

The purpose of the current work was to assess the systematic and taxonomic significance of the pollen morphological characteristics of the Multicaulia section of Hedysarum species found throughout Türkiye using scanning electron microscopy (SEM) and light microscopy (LM) techniques. For this reason, seven different species currently classified in the Multicaulia section were collected from various localities. The pollen grains were nonacetolyzed, prepared and directly measured according to the Wodehouse method. Pollen grains were found to be subprolate in H. nitidum but prolate in others and the exine sculpturing pattern was determined to be microreticulate-perforate in six taxa while only H. varium subsp. syriacum had reticulate-perforate sculpture. The minimum exine thickness was measured at 0.96 µm in H. varium subsp. varium, while among the investigated species, H. nitidum had an exine measurement of 1.38 µm. In this study, multivariate analysis was used to investigate nine qualitative and quantitative features. Data cluster analysis revealed that the pollen characteristics were important in helping to distinguish the different species from one another. The results demonstrated that the genus Hedysarum of the section Multicaulia was divided into two major groups based on variations in pollen dimensions. The usefulness of certain pollen morphological traits was assessed, and the congruency of the palynomorphological investigations was examined. The findings demonstrated the significance of pollen micromorphology in precisely identifying and categorizing the Multicaulia section. [ABSTRACT FROM AUTHOR]

Interpretation of past vegetation using pollen analysis depends on our understanding about the relationship between the modern vegetation and surface pollen assemblages. In the present study, we sampled the modern pollen-rain in a mixed environment of cultivated land and dry and wet tropical forests in central India. We established to which extent modern vegetation types are reflected in the pollen-rain and explained biases in the modern pollen spectra. Our study revealed that the modern pollen assemblages do not fully represent the extant regional vegetation, as many of the forest components, especially trees and shrubs, are either under-represented or remained palynologically silent in the pollen records. Low pollen productivity of most of the tropical deciduous taxa, owing to entomophily, as well as low preservation potential of some tree pollen are primarily responsible for this irregularity in their representation in the pollen spectra. Moreover, Shorea robusta and Tectona grandis pollen, despite being high pollen producers, are not encountered in any sample, which could be further attributed to their poor preservation in surface soil samples, as well as to their low (pollen) dispersal efficiency. Cerealia, Amaranthaceae, Caryophyllaceae, Brassicaceae, Cannabis sativa, Artemisia spp. and Alternanthera spp. indicate agricultural practices and other human activities around the respective study areas. Moreover, the consistent presence of Asteroideae pollen indicates pastoral activities, whereas Sporormiella spp., Sordaria spp., Podosora spp., Delitschia spp., and Cercophora spp. indicate local grazing and herbivory. [ABSTRACT FROM AUTHOR]

Palaeoclimatic and palaeoenvironmental proxy data are presented for the Late Quaternary based on mineralogical, geochemical and palynological analysis of a palaeosoil-sediment section in the lower Kürtün Valley (Samsun region, Northern Türkiye). The geochronology along the section is established based on OSL and radiocarbon dating. The base of the palaeosoil-sediment section consists of a palaeo-terrace fill of the Kürtün Creek dated to 108 ± 9 ka, corresponding to the last interglacial period (MIS5c). After this warm and humid period, the last ice age began. Sea level dropped and the Kürtün Stream deepened its bed. Fluvial terrace deposits were covered with colluvial materials and a palaeosoil sequence formed. The bottommost part of the palaeosoil formation carries the fingerprints of a dry climate of 68 ± 9 ka ago (MIS4). The middle part of the section coincides with MIS2 (28,959 cal BP) and is characterized by humid conditions with arid pulses accompanied by the occurrences of calcrete nodules. The palaeosoil-sediment section ends with the records of MIS1 (8381 cal BP), corresponding to warmer and more humid conditions. This study emphasizes the importance of palaeosoil-calcrete formation in the lower Kürtün Valley for explaining climate changes from MIS5c to MIS1. The results are compatible with studies conducted in the Eastern Mediterranean. High-resolution multi-proxy studies are recommended to better understand the connection between local climates and global climate phenomena in the Late Quaternary. [ABSTRACT FROM AUTHOR]

Monsoon precipitation plays a crucial role in shaping the diversity of vegetation in the Himalayas, both in terms of temporal and spatial distribution. While palynology has traditionally been employed to reconstruct the past climate of the Himalaya, there has been limited understanding of how monsoon-related changes affect the structure and distribution of vegetation. To address this, we analysed pollen data from a 3 m deep sedimentary profile in the higher Sikkim Himalaya to reconstruct monsoon driven changes in vegetation diversity. Our results show a highly fluctuating trend of pollen and diversity parameters at late-Pleistocene-Holocene transition for which fluctuating hydroclimatic conditions and differential pollen preservation in coarser sediments is attributed. During the Early Holocene (10,438–7934 cal yrs BP) favourable hydroclimatic conditions led to a rapid expansion of mixed broad-leaved forests, marked by higher values of richness and alpha diversity. Between 7934 and 5481 cal yrs BP, the region experienced moderate hydroclimatic conditions that facilitated expansion and diversification of woody taxa, and correlated with the global Holocene Climate Optimum (HCO). Conversely, from 5481 to3949 cal yrs BP, declining total pollen count (TPC), species richness, and alpha diversity indicates significant shifts in vegetation composition under deteriorating climatic conditions, which corresponds with the 4.2 ka event worldwide. From 3949 to 2049 cal yrs BP, an increasing yet variable trend in TPC and diversity indices, suggests warm-humid conditions prevailed in the region. During the last 1086 cal yrs, an increasing trend is recorded in the palyno assemblage and diversity parameters suggesting ameliorating climate, matches well with the Mediaeval Climate Anomaly (MCA). Our inferences suggest that the palyno assemblage and diversity parameters are quiet sensitive to warm and humid conditions. [ABSTRACT FROM AUTHOR]

Detailed palaeogeographical studies of the accumulative fan in the Serteyka River valley in W Russia and underlying biogenic deposits were carried out. The base of a representative core of biogenic sediments in the distal zone is dated to 1291 BC, while its top to 1631 AD. In this paper, palynological, plant macrofossils, Chironomide and Cladocera, geochemical, geochronological and sedimentological analysis were performed. Four phases of biogenic deposition were distinguished by pollen and geochemical analyses. Two of them coincide with the climatic fluctuation during Medieval Climate Anomaly and Little Ice Age. During the formation of the fan, overbank deposits were accumulated also, indicating numerous and intense floods, which are in line with the trend observed for other sites in this region. The accumulative fan is formed by lower, middle and upper deluvia and agricultural diamicton in its top. All units have specific sedimentological and geochemical features as well as low admixture of plant macrofossils. The beginning of the formation of this relief form dates back to the second half of the 17th century AD, and the end of the accumulation falls on the second half of the 18th century AD. Our work suggests that natural conditions had an impact on the formation and development of studied accumulative fan, however, the decisive factor causing the intensification of the slope processes were related with deforestation resulted from strong human impact, which was marked in palynological and macrofossils analyses (e.g. increase in the contribution of plants macrofossils related to agriculture). [ABSTRACT FROM AUTHOR]

The study of pre-European Māori agriculture in New Zealand is hindered by a lack of direct evidence in the form of plant remains. Presented here are the results of pollen and phytolith analyses of three archaeological excavations at Auckland Isthmus, Cambridge, and northern Taranaki. All sites show landscape disturbance by people, and the discovery of pollen of the Māori-introduced cultigen Cordyline cf. fruticosa (ti), suggesting that this species had a wide geographic range, well beyond that considered climatically limited by early ethnographic accounts. The pollen of C. fruticosa can be identified in the Pacific Islands, including New Zealand which has several endemic Cordyline species. The study describes this pollen type and reviews the locations and types of both macro- and microfossils of C. fruticosa previously reported in the Pacific Island region. [ABSTRACT FROM AUTHOR]

Quaternary palynology plays a pivotal role in investigating global climate change and various other research fields, serving as an essential tool for the quantitative analysis of paleoenvironment changes. However, due to the vast diversity of terrestrial ecosystems and intricate interactions between vegetation, climate, and human activities, further advancements are required in the following aspects within this discipline. (1) The accuracy of classification in pollen morphology and fossil pollen identification needs improvement, particularly at the species level. This represents a significant challenge in present Quaternary palynology. Computer-aided intelligent recognition holds promise as a solution for species identification based on more detail pollen morphology. (2) Most pollen-based vegetation and climate reconstructions overlook the significance of bare ground. Neglecting bare ground can lead to substantial inaccuracies when quantitatively reconstructing past vegetation and climate. (3) While pollen records provide reliable information on paleoclimate changes, current quantitative climate reconstruction models heavily rely on modern pollen datasets derived from present-day vegetation disturbed more or less by human activities. This introduces bias and uncertainties into paleoclimate reconstruction. (4) Although pollen can serve as an indicator of human activities, accurately quantifying the intensity of human influence remains challenging. Improving accurate identification of crop pollen, reconstructing reliable land cover/use data, and integrating multidisciplinary data may enhance the identification and quantification of signals related to human activity in pollen records. [ABSTRACT FROM AUTHOR]

An organic geochemical, petrographical, and palynological evaluation was conducted on 30 claystone outcrop samples of the Toraja Formation, along with a geochemical analysis of an oil seep in the Enrekang Sub-basin. The aim of the study was to determine the correlation between oil and source rock in terms of age, depositional environment, organic material sources, and maturity level. The total organic carbon content of the claystone samples varies from 0.03 to 4.52 wt%, which are classified as poor to excellent. The claystones are immature to post-mature with a mixture of Type II and III kerogen. Their vitrinite reflectance values range from 0.47 to 4.52 %Ro. The samples of Toraja Formation rock and the oil seep source rock might have a similar depositional environment, a deltaic marine depositional setting with high oxidizing conditions. Organic material sources for rock and oil samples are dominated by terrestrial input. The oil is inferred to have originated from the Paleogene source rocks, which correlates in age with the Toraja Formation. The recovered palynomorphs from the studied rock samples suggest a late Eocene to Oligocene age with a strong terrestrial influence of shallow marine depositional setting. The biomarker analysis shows that the rock samples have a more substantial contribution from the terrigenous higher plants, while the oil sample indicates a higher degree of marine influence. The maturity levels are also different between the oil (peak mature) and the analyzed rock samples (immature). It is inferred that the oil seep source rock is equivalent to the analyzed rock sample but more mature, having been deposited under more marine conditions. The oil seep source rock is not exposed and is located in the deeper part of the basin. A deeper marine facies (i.e. distal delta front and prodelta facies) in front of the distributary mouth bar within a delta is interpreted as the source rock of the oil seep sample. [ABSTRACT FROM AUTHOR]

The new species Rosa aharbalensis is described and illustrated from Tehsil Damhal Hanjipura of Jammu and Kashmir. It is morphologically similar to Rosa canina, but characterized by having velvety leaves, leaves with up to 9 leaflets, hairy stipules with glandular margins, hairy and eglandular pedicels, one bract and two bracteoles, sepal margins with numerous pinnae, emarginate and obcordate petals, hairy style, larger number of hips per inflorescence, more numerous stamens per flower, hips (pseudo fruits) sub‐globose to ovoid, achenes with sparse hairs, thin pollen exine and indistinct striae and narrow grooves on the exine surface. [ABSTRACT FROM AUTHOR]

Triaspis hypericoides currently comprises three accepted subspecies endemic to woodland savannas of southern continental Africa. After an unusual population belonging to this complex was collected in southwestern Angola, we re‐evaluated the classification of this group. This study was based on the analysis of type specimens, protologues, field photographs and herbarium sheets of all subspecies within T. hypericoides. We reinstate T. canescens, T. hypericoides and T. nelsonii based on differences in leaf, flower and fruit traits. Additionally, the Angolan population is proposed here as a new species of Triapis endemic to the dry miombo woodlands of Bicuar National Park, Huíla Province, southwestern Angola. Triaspis bicuarensis sp. nov. is easily distinguished from T. nelsonii by its alternate (versus opposite) leaves, ovate to widely ovate (versus widely ovate to very widely ovate) leaf laminas, rounded (versus sagittate) leaf base, flat (versus undulate) margins, sparsely white‐tomentose (versus glabrous to glabrescent) abaxial leaf surface, petiole 4–8 mm long (versus 2–3 mm long), compound inflorescences in thyrses (versus corymbs) and bracteoles inserted below apex of peduncles (versus in the middle of peduncles). An identification key to all species belonging to this species complex is presented alongside a complete morphological description for the new species, photographic plates and comments on the distribution, ecology, palynology and taxonomy. These results underline the need for continued revisions of the taxonomy of the neglected African genera of Malpighiaceae. [ABSTRACT FROM AUTHOR]

This article summarizes a study conducted in the Brazilian Atlantic Forest on the pollen carried by Neotropical hawkmoths on their proboscises. The study found that hawkmoths do not show high specificity in their choice of flowers, as individuals with both short and long proboscises visited the same flower species. The most abundant pollen type was Pera from the Peraceae family. The study also emphasizes the importance of interdisciplinary research in informing preservation policies for the Atlantic Forest. [Extracted from the article]