Pollen Spores Research Articles

The Quantitative Reconstruction of Paleoclimate in the Huangling Region of the Chinese Loess Plateau during the Middle and Late Holocene

The Huangling region is located in the central part of the Chinese Loess Plateau, which is sensitive to climate change due to the transitional characteristics of the natural environmental zone in which it is located. In this study, we utilized a spore–pollen analysis of the Tianjiahe (TJH) profile in Huangling to apply the pollen–climate factor conversion function method. This approach allowed us to quantitatively reconstruct the paleotemperature and paleoprecipitation of the Huangling area during the Middle and Late Holocene. The results show that the Huangling area experienced four climatic stages during the Middle and Late Holocene, including mild and slightly humid → warm and humid → warm and slightly humid → warm and humid. Except for the period of 5.3–4.72 kaBP, during which the climate was relatively cool and dry compared to the present, the climate in the remaining period (4.72–0.03 kaBP) was warmer and more humid than that of the present. The above results provide an important insight for further exploring the mechanism of paleoclimate change and predicting future climate change.

Subfossil Spore–Pollen Spectra of Northern Yakutia as a Key to the Interpretation of Paleoecological Studies

Subfossil Spore–Pollen Spectra of Northern Yakutia as a Key to the Interpretation of Paleoecological Studies

Late Quaternary Dynamics of Landscape and Climate in the North of the West Siberian Plain Revealed by Paleoecological Studies of Peat and Lake Sediments

West Siberian mires covering more than 50% of area in the subarctic are still poorly investigated despite their thick peat sediments suitable for paleogeographic research of past long-term landscape and climatic changes. In this research, a combination of paleoecological methods were used, including the analysis of pollen, spores, diatoms, NPPs, and macrofossils, the measurement of peat humification, and quantitative paleoclimate reconstruction. This multi-proxy approach was applied to study a palsa bog (frost peat heave mound) located in the north of western Siberia on the border of the northern taiga and forest–tundra (65°18′56″ N, 72°52′27″ E). Chronology is based on 21 radiocarbon dates, which were calibrated in CLAM. Studies have shown that sediments of palsa bog Nadym of a 1050 cm thickness were formed both in the Holocene and earlier periods of the Quaternary. Radiocarbon dating worked well for peat sequences (610 cm thick), but failed for underlying lacustrine and mineral sediments (440 cm thick). Numerous remains of salt-water diatoms and exotic Neogene pollen were found in the lacustrine sediments (650–850 cm). The oldest sediments (850–1050 cm) have signs of secondary epicryogenic diagenesis in the form of cryogenic iron-enriched granules. Both lacustrine and bottom sediments contain abundant coniferous pollen. At the same time, spore–pollen complexes dated to the Last Glacial Age were not found in low sediments because of failed dates. To explain this, the authors turn to the hypothesis of glyacioisostatic compensation, according to which the study area was uplifted during the Last Glacial Age and the ancient deposits underwent secondary diagenesis in subaerial conditions. Holocene lacustrine sedimentation began to form about 9800 cal. a BP. These lacustrine sediments turned out to be enriched in redeposited Neogene pollen and diatoms. It was interpreted as an influence of excess humid climate in combination with geological subsidence of landscape in the study area during the Early Holocene. This caused lake formation and introduction of exotic microfossils via surface run-off from higher-relief areas in the catchment. Syngenetic sedimentation in the Nadym section is associated only with peat-mire deposits covering the last 8400 cal. a BP. For this time, the dynamic of vegetation cover and quantitative changes in paleoclimate were reconstructed using spore–pollen, macrofossil, humus, and NPP data as well as the information–statistical method of V.A. Klimanov. The spore–pollen analysis revealed four main phases in the development of vegetation cover: 1. Spruce–birch forests with open meadows and lakes (8400–7600 cal. a BP); 2. Dominance of spruce forests and thawed eutrophic (minerotrophic) mires (7600 to 6500 cal. a BP); 3. Coniferous–birch forests and thawed mesotrophic mires (6500 to 4500 cal. a BP); 4. Birch–pine forests and oligotrophic (ombrotrophic) bogs with permafrost mounds—palsa bogs (approx. the last 4500 years). Quantitative reconstructions of paleoclimate based on pollen data show that in most cases the periods of a sharp decrease in mean January and mean July temperatures coincided with episodes of low solar activity. The assumption was made about the determining influence of solar activity on the formation of permafrost in the soils and mires of the study area. Sun minima caused permafrost formation in the mire periodically since 8400 cal. a BP in study peatland, but complete freezing of the peat mire and formation of the palsa bog occurred at c. 2800 cal. a BP.

Reconstruction of Late Glacial Conditions of Exogenic Landscape Formation of Central Kamchatka: Data on Spore–Pollen Analysis

Reconstruction of Late Glacial Conditions of Exogenic Landscape Formation of Central Kamchatka: Data on Spore–Pollen Analysis

Spider Web: A Natural Sampler for Analysis of Airborne Pollen–Spores from Santiniketan, West Bengal

Spider Web: A Natural Sampler for Analysis of Airborne Pollen–Spores from Santiniketan, West Bengal

Measurement report: An exploratory study of fluorescence and cloud condensation nuclei activity of urban aerosols in San Juan, Puerto Rico

Abstract. Many atmospheric aerosols are cloud condensation nuclei (CCN), capable of activating as cloud droplets when the relative humidity exceeds 100 %. Some primary biological aerosol particles (PBAPs), such as plant spores, pollen, or bacteria, have been identified as such CCN. Urban environments are a source of these bioaerosols, some of which are naturally produced by the local flora or are transported from surrounding regions and others of which are a result of human activities. In the latter case, open sewage, uncovered garbage, mold or other products of such activities can be a source of PBAPs. There have been relatively few studies, especially in the tropics, where PBAPs and CCN have been simultaneously studied to establish a causal link between the two. The metropolis of San Juan, Puerto Rico, is one such urban area with a population of 2 448 000 people (as of 2020). To better understand the fluorescent characteristics and cloud-forming efficiency of aerosols in this region, measurements with a wideband integrated bioaerosol spectrometer (WIBS), a condensation nuclei (CN) counter and a CCN spectrometer were made at the University of Puerto Rico – Río Piedras Campus. Results show that the CCN / CN activation ratio and the fraction of fluorescing aerosol particles (FAPs) have repetitive daily trends when the FAP fraction is positively correlated with relative humidity and negatively correlated with wind speed, consistent with previous studies of fungi spores collected on substrates. The results from this pilot study highlight the capabilities of ultraviolet-induced fluorescence (UV-IF) measurements for characterizing the properties of FAPs as they relate to the daily evolution of PBAPs. The use of multiple excitation and emission wavelengths, along with shape detection, allows the differentiation of different PBAP types. These measurements, evaluated with respect to previous, substrate-based analysis of the local fungal and pollen spores, have established a preliminary database of measurements that future, longer-term studies will build upon.

Palynology of the North Karanpura basin, Bihar, India 4. Subsurface Palynology of the bore-hole no. K.5

The present paper deals with subsurface Palynology of Barakar Stage and Barren Measures present in the bore-hole no. K.5, located in the Baral-Raniganj-Kevendai area, North Karanpura basin (Sheet no. 73E/1), Bihar, India. 34 dispersed spore pollen genera and 39 species have been recovered from Barakar Stage while Barren Measures have yielded 51 genera and 67 species. The palynological assemblage of both Stages comprises trilete, monolete, monosaccate, bisaccate, polysaccate, polyplicate and colpate spores-pollen. The palynological assemblage of Barren Measures have been subdivided into three palynological zones on the basis of percentage of spores-pollen in the material.

Amber flora and fauna from Early Eocene Vastan Lignite Mine, Cambay Basin, Gujarat: Ecological Diversity and Environmental Significance

Abstract Micro and macrofossil assemblage have been recovered and documented from the lignite beds of the Vastan lignite mines, Cambay Basin, Gujarat. These are extracted after dissolving amber pieces inclusive of pollen spores, epiphyllous fruiting fungal bodies, algal elements, insect fossils with some unidentified biotic groups. Of these, the major dominant flora belongs to angiosperm origin, in accompaniment to pteridophyte spores and fungal elements. Recorded palynotaxa viz. Proxapertites, Spinizonocolpites, Neocouperipollis and Acanthotricolpites are significant elements for tropical humid vegetation. Rich terrestrial amber palynomorphs and palynodebris suggest proximity source vegetation. Characteristic biotic interactions within the dense evergreen tropical rain forest environment is suggestive of mutual association among groups during the Early Eocene and share close affinities with those of Kutch and Barmer, Bikaner and Nagaur basins.

Decline of Neogene lignite formation as a result of vegetation and climate changes reflected in the middle Miocene palynoflora from the Ruja lignite deposit, SW Poland

The paper presents results of a palaeobotanical investigation of the borehole core Komorniki 97/72 from the Ruja lignite deposit, Lower Silesia. In the deposit lignites of three (2nd Lusatian, 2nd A Lubin, and 1st mid-Polish) middle Miocene groups of seams are present. The lignites of the 1st and 2nd groups are important correlation horizons throughout much of the Polish Lowlands and eastern Germany. The results of the palynological studies (spore–pollen, algae and fungi) and plant macroremains studies show that during the mid-Miocene mires' development, the vegetation was characteristic of wetlands (i.e., swamp and riparian forests, shrub bogs, and reed marshes) as well as mesophytic forests. The results were also used for palaeoclimatic investigation. The mean annual temperature (MAT), for each of the three sections, based on the coexistence approach (CA) method, was estimated in the range of 15.7–17.8 °C. Nevertheless, the frequency of thermophilous (palaeotropical and palaeotropical/warm-temperate) taxa indicate climate changes during the formation of the studied sediments. Composition of the spore–pollen spectra from the 2nd Lusatian seam (i.e., the presence of Meliaceae and Sapotaceae, which currently have pantropical distribution) show that the climate was humid and warm, close to subtropical. Later, many palaeotropical taxa disappeared, and the composition of the spore–pollen spectra indicates a warm temperate climate with slight fluctuations. Above the 1st mid-Polish seam, the climatic conditions changed in a way that did not favor the further formation of lignite deposits. These results correspond with the current understanding of climate change in the middle Miocene in Europe.

Subfossil Spore–Pollen Spectra from Larch Forests of Central Evenkia: Special Aspects of Interpretation for Paleoecological Research Purposes

Subfossil Spore–Pollen Spectra from Larch Forests of Central Evenkia: Special Aspects of Interpretation for Paleoecological Research Purposes

Diagnostics of the Beginning of Agricultural Development of the Northwest of the East European Plain by Spore–Pollen Spectra

Diagnostics of the Beginning of Agricultural Development of the Northwest of the East European Plain by Spore–Pollen Spectra

Palinostratigraphy and Paleoenvironments in the Gorodishchi Section (Middle Volga River Region, Kimmeridgian–Hauterivian)

Abstract —Eight dinocyst-based and three spore- and pollen-based biostratigraphic units are defined in the Kimmeridgian, Volgian, and Hauterivian of the Gorodishchi section, based on a biostratigraphic analysis of the successions of marine and terrestrial palynomorphs. Algological assemblages are described in more detail, and additional criteria for the definition of dinocyst zones established by previous researches are given. A more detailed biostratigraphic subdivision of the middle part of the Volgian is proposed. A local dinocyst zone in the Hauterivian and a biostratigraphic succession of spore–pollen units in the entire section are described for the first time. The research results demonstrate that the boundaries of many palynostratigraphic units exhibit a considerable correlation potential. Based on a biofacies analysis of the microphytoplankton, the dynamics of transgressive–regressive events is studied in relation to the accompanying oxygen and trophic conditions. Possible relationships between marine paleoenvironments and climatic changes reconstructed on the basis of spore–pol­len data are discussed.

Некоторые исследования рода Camellia L. (Theaceae) с представителями во Вьетнаме

Many studies have been conducted to classify the genus Camellia, yet they have not been entirely consistent. Therefore, doing research on some of the taxonomic systems of the genus Camellia will serve as the basis for the classification and arrangement of recently discovered species into a consistent system. A series of studies based on morphology as well as molecular biology techniques, the classification of pollen spores, and the analysis of leaf anatomy were examined. The systems based on morphological characteristics were inherited and widely recognized, thereby becoming an appropriate method to classify the genus Camellia with representatives in Vietnam.

Palaeoclimate of the Paleogene Dongying Formation in Bozhong Sag of Bohai Bay Basin

It was showed that the sedimentary environment of lacustrine basins is more susceptible to basin size than that of marine basins, leading to frequent changes in sedimentary environment and large differences in sediment supply and types. Based on the comprehensive analysis of clay minerals, spore pollen, major elements and trace elements, the sedimentary environment of Dongying Formation and its evolution in Bozhong Sag were studied. The results showed that during the sedimentary period of Dongying Formation, the study area was in a subtropical warm and humid climate as a whole. In addition, the vertical distribution of spore pollen and algae was divided into four zones and each one represents different sedimentary environments. Combination zone I is characterized by a large number of spore pollen and algae, including juglanspollenites verus, ulmipollemites minor, abietineaepollenites and pinuspollenites, taxodiaceaepollenites hiatus, leiosphaeridia and granodiscus, and it indicates a relatively hot and dry climatic; Combination zone II mainly contains juglanspollenites verus, ulmipollemites minor, abietineaepollenites and pinuspollenites, pediastrum and leiosphaeridia. Compared with I, the number of spore pollen and algae decreases, but the number of pediastrum increases a lot, which represents warm and humid climate. The combination zone III is dominated by abietineaepollenites and pinuspollenites and chaetosphaeridium, and the species and quantity decrease significantly. It indicates a relatively hot and humid climate at that time. Combination zone IV contains a small amount of spore pollen and algae, and it means the climate was warm and humid at that period. The frequent changes of sedimentary environment in lacustrine basins are influenceded by regional tectonic environment and basin scale. Using S/A and E-T parameters, the paleoclimate in the study area was delineated and 10 sedimentary environment interfaces were identified, which further illustrated the characteristics of frequent fluctuations of sedimentary environment in lacustrine basins.

Ultrasound-assisted ethanol extraction of Actinidia arguta pollen possesses antioxidant activity and protects DNA from oxidative damage.

Actinidia arguta pollen owns abundant nutrients, such as vitamins, polyphenols, etc., however, little research on its antioxidant ability and biological function was conducted. In this study, we observed A. arguta pollen spore structure by SEM (Scanning electron microscope), analyzed the phenolic composition of A. arguta pollen extract (AAPE) obtained by four extraction methods (A: ultrasound-assistedextraction with water, B: heatrefluxextraction withwater, C:ultrasound-assistedextraction with ethanol, and D: heatrefluxextraction withethanol). Total phenolic content, total flavonoid content, antioxidant activities (ferric reducing/antioxidant power [FRAP], chelating activity, and DPPH⋅ scavenging activity) were also determined. Finally, we investigated its protective effect on DNA and lymphocytes damage response to oxidative stress. The results showed that the morphology of A. arguta pollen was similar to other pollen of the genus A. Lindl., but differs from them slightly in the specific morphology indicators. What is more, AAPE obtained by different extraction methods exhibited a protective effect against DNA oxidative damage, they also possessed a strong cytoprotection effect on mouse lymphocytes, especially the extraction obtained by method C, which had the highest total phenolic content (15.05±0.34mg GAE/g), strong ferrous ion-chelating ability (0.37±0.023mg Na2 EDTA/g), DPPH⋅ scavenging activity (IC50 =0.14±0.04mg/ml), and FRAP (7.13±0.33mg Trolox/g). This paper provided a new edible natural antioxidant for human which will protect us from oxidative stress. PRACTICAL APPLICATIONS: This study was the first to report the morphology of Actinidia arguta pollen by SEM analysis, and studied the effects of different extraction methods on antioxidant activities and cytoprotective effect of A. arguta pollen extract. We believed that our research makes a significant contribution to the literature, because the results of this research provide a reference for the development of a new edible natural antioxidant.

The use of spore–pollen assemblages to reconstruct vegetation changes in the Permian (Lopingian) Zechstein deposits of northeast England

New boreholes have enabled, for the first time, extensive palynological sampling through the entire Lopingian Zechstein sequence of northeast England. Palynomorph assemblages have been recovered from throughout the sequence from all five of the evaporation-replenishment cycles (EZ1–EZ5). These assemblages are dominated by pollen grains, with rare trilete spores, and even rarer marine forms such as acritarchs and foraminiferal test linings. The assemblage of pollen grains is of low diversity (35 species) and dominated by taeniate and non-taeniate bisaccate pollen. The assemblage varies to only a limited extent both within and between cycles, although some minor variations and trends are documented. Based on the composition of the dispersed spore–pollen assemblages, and previous work on the Zechstein megaflora, the hinterland vegetation is interpreted as being dominated by conifers that inhabited a semi-arid to arid landscape. This flora is shown to have persisted throughout the entire Zechstein sequence, despite previous assertions that it disappeared as conditions became increasingly drier over the course of the latest Permian.

Late Cretaceous palynology and paleoenvironment of the Razzak-3 well, North Western Desert, Egypt

Palynological analysis of the Bahariya and Abu Roash Formations from the Razzak-3 (RZ-3) well, North Western Desert, Egypt, has yielded rich and very-well-diversified spores, pollen and dinoflagellate cysts which allow subdividing the studied rock units into four pollen/spore (PS) zones and three dinoflagellate cyst (D) zones. Miospores are abundant in the Cenomanian, while dinoflagellates predominate the Turonian-Santonian. A barren interzone delineates the oceanic anoxic event 2 and embraces member “F” of the Abu Roash Formation. The marine/nonmarine palynomorph ratio in the studied samples indicate that the Bahariya Formation was deposited in a nearshore paleoenvironment affected by continental sources with an arid to semiarid hinterland having local or seasonal humid conditions. Deposition of the Abu Roash Formation took place in the transitional zone between the inner and outer shelf. Dinoflagellate cysts in this study are of the Tethyan Realm.

Vegetation and Microtheriofauna Dynamics during the Late Glaciation and Holocene in the Yugyd-Va National Park

The results of studies of the Late Pleistocene and Holocene spore–pollen spectra and the microtheriofauna of loose deposits of four cave localities located in the Shchuger and Kozhym river basins within the territory of the Yugyd-Va National Park on the western slope of the Subpolar Urals are discussed. Assessment of the age of sediments from the karst cavities was based on the data of AMS radiocarbon dating of mammalian bones. The speleogenic formations of the localities studied contain layers assigned to the final stage of the degradation of the Polar Ural (Late Valdai) glaciation (Middle to Late Dryas) and to the Preboreal, Boreal, and Subatlantic periods of the Holocene. Cryoxerophilous tundra species predominated (88.3%) in the fossil microtheriofauna assemblage identified for the Allerod. The Middle Dryas and Allerod, the cold and warm periods of the Late Glacial, respectively, were reflected by the spore–pollen spectra. The microtheriofauna on the western slope of the Subpolar Urals remained quite cryophilous by the end of the Late Dryas. The broad distribution of yernik thickets and goosefoot–gramineous–mixed herb assemblages during that time has been established. The vegetation of the western foothills of the Subpolar Urals consisted of grass–shrub tundra with sparse spruce trees during the Late Preboreal cooling period. The microtheriofauna community also had a tundra-like composition. The presence of dark coniferous taiga forests in the south of the Subpolar Urals and sparse spruce–birch forests with pine and dwarf birch in the undergrowth in the north of the area during the Boreal period has been established. The rodent fauna acquired a forest-like character by that time. Northern taiga dark coniferous forests of spruce with a significant admixture of pine developed on the western slope of the Subpolar Urals by the middle of the Subatlantic period, and the content of tundra elements in the stands increased by the end of this period. The microtheriofauna of the studied region had a typical forest appearance characteristic of all Late Holocene taiga communities in northeastern Europe.

Wall ultrastructure of the Permian pollen grain Lueckisporites virkkiae Potonié et Klaus 1954 emend. Clarke : Evidence for botanical affinity

Permian spore–pollen assemblages are dominated by striate bisaccate pollen grains. The botanical affinity of many of these is unknown, which limits their value in ecological reconstruction and biostratigraphy. Lueckisporites virkkiae Potonié et Klaus 1954 emend. Clarke 1965 is a bitaeniate bisaccate pollen grain of uncertain botanical affinity that dominates late Permian Euramerican assemblages, but also bridges phytogeographical provinces. It is classified into three “variants,” which capture a spectrum of morphological variability, but further complicates matters by questioning whether it comprises a natural taxon. Here we report on a TEM analysis of the gross structure and wall ultrastructure of L. virkkiae variants from the upper Permian (Lopingian) of Kimberley, Nottinghamshire, UK. The variants have the same gross structure and wall ultrastructure. The exine consists of a three-layered ektexine composed of a thin tectum, an alveolate infratectum and a thin foot layer, subtended by a solid endexine. Alveolae are either small and rounded, columellate-like, or irregularly shaped, depending on whether the exine is viewed in transverse or longitudinal section. Sacci are protosaccate, with narrow and irregular, or large and voluminous, endoreticulations. Similarities in gross structure and wall ultrastructure suggest that the current taxonomic grouping is correct with the variants representing the range of variation within a single species. We suggest that the differences in morphology are subtle and attributable to harmomegarthy. Comparisons with fossil and modern conifer pollen grains suggest an affinity with conifers. Co-occurrence with the Zechstein conifer macrofossil Pseudovoltzia liebeana (Geinitz) Florin 1880 (Majonicaceae) indicates this as a possible source.

Pollen-spore assemblages of the Navarro Group (Maastrichtian) of Texas, USA: biostratigraphical and palaeoecological significance

Diverse assemblages of spore–pollen floras are present in all formations in the Navarro Group (Maastrichtian) in outcrops of the Austin Section and the subsurface Frio Section. The stratigraphic ranges and relative abundance of spore, pollen, dinoflagellate cysts and acritarchs were used to establish four biozones (A, B, C and D). Biozone A corresponds to the undifferentiated Neylandville Marl–Nacatoch Sand Formation; Biozone B corresponds to the Corsicana Marl Formation; Biozone C corresponds to the lower half of the Kemp Clay Formation; and Biozone D corresponds to the upper half of the Kemp Clay Formation. Biozonal boundaries do not always correspond to formation boundaries. Biozones A, B, C and D of the Austin section are correlated with the subsurface Frio section. The zonal boundaries based on spore–pollen distribution in the Austin and the Frio sections correlate well with the timelines established in these two sections based on dinoflagellate cysts and acritarchs. All Navarro Group formations except the Olmos were deposited in marine environments ranging from intertidal to outer shelf. Olmos Formation sediments were deposited in a range of coastal terrestrial environments with occasional minor influences of the sea. Three transgressive phases (T1, T2 and T3) separated by four regressive phases (R1, R2, R3 and R4) are recognized. During the Maastrichtian the floral composition in Texas changed from predominantly pteridophytic and bryophytic in the early Maastrichtian to predominantly angiospermous flora in the middle and late Maastrichtian. Tropical to subtropical climates prevailed in Texas throughout the Maastrichtian but highland regions such as Llano Uplift and nearby Marathon and Arbuckle Mountains were cooler regions with a temperate to sub–temperate climate. The upper part of the Navarro Group records a gradual cooling trend suggested by the dominance of temperate angiosperm pollen taxa.