Search Results (27)

The Bełchatów Lignite Mine (BLM) in central Poland, one of Europe’s largest Neogene lignite deposits, provides key insights into palaeofloral evolution. Located in the Kleszczów Graben, the BLM consists of four distinct lithological units: subcoal, coal, clayey-coal, and clayey-sandy units. The study presents a palynological investigation of 31 samples from all units, identifying 78 sporomorph taxa, including 10 plant spores, 15 gymnosperm pollen, and 53 angiosperm pollen taxa. Pollen grains from angiosperms and gymnosperms were consistently observed in all samples, while plant spores were scarce. The analysis reveals three distinct palynological zones, reflecting shifts in vegetation. The first zone is characterized by swamp, riparian, and mixed mesophilous forests, dominated by Taxodium/Glyptostrobus, Ulmus, Carya, Engelhardia, Pterocarya, and Quercus. In the second zone, slightly cooler climatic conditions led to the decline of Taxodium/Glyptostrobus and Alnus, indicating a deterioration of swamp forests. The third zone marks a subsequent recovery of these forests. Palaeoclimatic interpretations indicate three phases: a subtropical-humid climate during the Early Miocene, fluctuating humidity in the late Early Miocene, and a transition to a warm-temperate and humid climate in the Late Miocene. Full article

Calculus deposits of individuals unearthed from Torre Velha (TVCA) and Mós (MOTM), Necropolis, were analyzed to obtain insights about diet, crop cultivation, and plant use. All samples (n = 11) revealed micro-remains, including starch grains, pollen grains, fungal spores, and sclerenchyma fibers. Starch grains were detected in all studied specimens, belonging mostly to wheat and rye, with fewer to barley and various pulses, with fava beans being the most relevant. Mós samples also showed evidence of millets and pollen grains. These include genera with known medicinal properties, suggesting their intentional use for medical purposes. Fungal spores were isolated from samples of both sites, with higher yield in Mós. A major diversity of micro-remains was obtained in Mós individuals, although any differences must be interpreted with caution. The present work is the first to provide insights into the medieval diet in the Northeast region of Portugal through dental calculus analysis and, when combined with written sources, it contributes to the knowledge of the cultural heritage of the Middle Age diets. Full article

In recent years, China has invested substantial funds in ecological restoration, achieving significant accomplishments. The forest coverage rate in the Chengde Bashang area, located in the transitional zone between the monsoon and non-monsoon regions, has now reached 82%. However, the area has also encountered a series of environmental issues, including lake shrinkage, soil salinization, and large-scale die-offs of planted forests. Whether the forests in this region can achieve sustainable development in the future, and whether ecological restoration should prioritize tree planting or grass cultivation, are critical questions that require attention. By studying the historical vegetation dynamics in afforested areas, we can better understand the relationship between climatic environmental changes and vegetation, providing baseline data for future ecological restoration. This study utilized AMS ¹⁴C dates to establish a chronological framework for the core and employed pollen to investigate vegetation dynamics over the past 5000 years in the artificial Larix Mill. forest area. The vegetation and environmental history of this core can be divided into three zones: Zone 1 (5100–4100 a B.P.): vegetation was dominated by pine and spores, with low herbaceous pollen content. Zone 2 (4100–1400 a B.P.): vegetation was primarily herbaceous. Zone 3 (1400 a B.P.–present): arboreal pollen content increased slightly, but herbaceous plants remained dominant. This period included the warm–dry Medieval Warm Period (1400–900 a B.P.), the cold–humid Little Ice Age (900–300 a B.P.), and the recent 300 years of anthropogenic disturbance. Notably, the large-scale afforestation efforts in recent decades are clearly reflected in the profile. A comparative analysis of records from the monsoon–non-monsoon transition zone reveals that, except for Angulinao Lake, other records were dominated by herbaceous vegetation over the past 2000 years. Additionally, the Mu Us Sandy Land, Hunshandake Sandy Land, Hulunbuir Sandy Land, and Horqin Sandy Land in China have experienced aeolian sand accumulation over the same period. Given the anticipated warming–desiccation trend, phytoremediation strategies should favor xerophytic shrubs and herbaceous over monospecific forest plantations. Full article

This study investigates the composition, abundance, and seasonal variability of airborne pollen in Siirt, a transitional region between the Irano-Turanian and Mediterranean phytogeographical zones in southeastern Türkiye. The main objective was to assess pollen diversity and its relationship with meteorological parameters over a two-year period (2022–2023). Airborne pollen was collected using a Hirst-type volumetric pollen and spore trap; a total of 18,666 pollen grains/m³ belonging to 37 taxa were identified. Of these, 70.67% originated from woody taxa and 29.33% from herbaceous taxa. Peak concentrations occurred in April, with the lowest levels in December. The dominant taxa, all exceeding 1% of the total, were Pinaceae (31.00%); Cupressaceae/Taxaceae (27.79%); Poaceae (18.42%); Moraceae (4.23%); Amaranthaceae (2.42%); Urticaceae (2.13%); Quercus (1.55%); Fabaceae (1.29%); and Rumex (1.02%). Spearman’s correlation analysis revealed significant relationships between daily pollen concentrations and meteorological variables such as temperature, humidity, precipitation, and wind speed. These findings highlight that both climatic conditions and the surrounding vegetation, shaped by regional land cover, play a crucial role in determining pollen dynamics. In conclusion, this study provides the first aerobiological baseline for Siirt and contributes valuable data for allergy-risk forecasting and long-term ecological monitoring in southeastern Türkiye. Full article

Molds are frequent indoor contaminants, where they can colonize many materials. The subsequent aerosolization of fungal spores from moldy surfaces can strongly impact indoor air quality and the health of occupants. The investigation of fungal contamination of habitations is a key point in evaluating sanitary risks and understanding the relationship that may exist between the fungal presence on surfaces and air contamination. However, to date there is no “gold standard” of sampling indoor air for such investigations. Among various air sampling methods, impingement can be used for capturing fungal spores, as it enables real-time sampling and preserves analytical follow-up. Its efficiency varies depending on several factors, such as spore hydrophobicity, sampling conditions, etc. Sampling devices may also impact the results, with recovery rates sometimes lower than filtration-based methods. The Coriolis µ air sampler, an impingement-based device, utilizes centrifugal force to concentrate airborne particles into a liquid medium, offering flexibility for molecular analysis. Several studies have used this device for air sampling, demonstrating its application in detecting pollen, fungal spores, bacteria, and viruses, but it is most often used in laboratory conditions. The present case study, conducted in a moldy house, aims to investigate the efficiency of this device in sampling fungal spores for DNA analysis in indoor environments. The results obtained suggest that the use of this device requires an optimized methodology to enhance its efficiency and reliability in bioaerosol research. Full article

Primary Biological Aerosol Particles (PBAPs) range in size from a few nanometres to hundreds of micrometres and include particles such as pollen and fungal spores, which are significant due to their prevalence and potential to induce allergic reactions and other health-related issues. This study employs real-time fluorescence spectroscopy devices, the Wideband Integrated Bioaerosol Sensor (WIBS-NEO) and IBAC-2, to monitor PBAPs in the urban environment of Dublin, Ireland, during a six-week campaign in the summer of 2019. The WIBS-NEO demonstrated moderate correlations (R² = 0.5–0.7) in comparison with Hirst volumetric air sampler data for pollen and fungal spore concentrations following appropriate data filtering. In contrast, the IBAC-2 showed poor correlation with ambient fungal spore concentrations and lacked the necessary particle size ranges for reliable pollen measurement. Comparative analysis between WIBS-NEO and IBAC-2 revealed moderate correlation (R² ≈ 0.6) for small fluorescent particles (fluorescent particles between 0.7 and 1.5 μm optical diameter) but lower correlation for larger particles and specific bioaerosol types. The findings suggest that while the WIBS-NEO is effective for real-time bioaerosol monitoring, further refinement is needed for IBAC-2. This study underscores the potential of using advanced real-time monitoring tools in urban environments and highlights the need for continued development to address current limitations. Full article

Background: Bioaerosols can represent a danger to health. During SARS-CoV-2 pandemic, portable devices were used in different environments and considered a valuable prevention tool. This study has evaluated the effectiveness of the air treatment device “AEROK 1.0^®” in reducing microbial, particulate, and pollen airborne contamination indoors, during normal activity. Methods: In an administrative room, airborne microbial contamination was measured using active (DUOSAS 360 and MD8) and passive sampling; a particle counter was used to evaluate particle concentrations; a Hirst-type pollen trap was used to assess airborne pollen and Alternaria spores. Statistical analysis was performed using SPSS 26.0; p values < 0.05 were considered statistically significant. Results: The airborne bacterial contamination assessed by the two different samplers decreased by 56% and 69%, respectively. The airborne bacterial contamination assessed by passive sampling decreased by 44%. For fungi, the reduction was 39% by active sampling. Airborne particles (diameters ≥ 1.0, 2.0 μm) and the ratio of indoor/outdoor concentrations of total pollen and Alternaria spp. spores significantly decreased. Conclusions: The results highlight the effectiveness of AEROK 1.0^® in reducing airborne contamination. The approach carried out represents a contribution to the definition of a standardized model for evaluating the effectiveness of devices to be used for air disinfection. Full article

Numerous Aspergillus fumigatus (Af) airborne spores are inhaled daily by humans and animals due to their ubiquitous presence. The interaction between the spores and the respiratory epithelium, as well as its impact on the epithelial barrier function, remains largely unknown. The epithelial barrier protects the respiratory epithelium against viral infections. However, it can be compromised by environmental contaminants such as pollen, thereby increasing susceptibility to respiratory viral infections, including alphaherpesvirus equine herpesvirus type 1 (EHV-1). To determine whether Af spores disrupt the epithelial integrity and enhance susceptibility to viral infections, equine respiratory mucosal ex vivo explants were pretreated with Af spore diffusate, followed by EHV-1 inoculation. Spore proteases were characterized by zymography and identified using mass spectrometry-based proteomics. Proteases of the serine protease, metalloprotease, and aspartic protease groups were identified. Morphological analysis of hematoxylin-eosin (HE)-stained sections of the explants revealed that Af spores induced the desquamation of epithelial cells and a significant increase in intercellular space at high and low concentrations, respectively. The increase in intercellular space in the epithelium caused by Af spore proteases correlated with an increase in EHV-1 infection. Together, our findings demonstrate that Af spore proteases disrupt epithelial integrity, potentially leading to increased viral infection of the respiratory epithelium. Full article

The climatostratigraphic scale of the Upper Middle Pleistocene in the northwest of the East European Plain contains a number of controversial issues, one of which is the position of the Likhvin (Holstein) Interglacial and lesser warm (interstadial) climatic events. To approach this problem, we have studied two sections of Quaternary deposits, Bolshaya Kosha (a well-known and long-studied natural exposure) and Nazarovo (a new, previously unknown section studied in a borehole), in which warm intervals of the Middle Pleistocene are recognized. In both sections, we performed lithological and paleobiological (carpological, spore-pollen) analyses and luminescence dating. In the Bolshaya Kosha section, seeds of the extinct species Caulinia goretskyi were revealed, which allowed us to attribute the obtained IRSL (ca 250–260 ka) dates to the post-Likhvin Bolshaya Kosha interstadial. The sum of data let us propose that both our IRSL and recently published ²³⁰Th/U dates (ca 240–290 ka) underestimate the age by 10–15%, and the post-Likhvin Kosha interstadial deposits were formed in the late MIS 9. In the Nazarovo section, palynological study showed the conditions of a relatively warm interstadial, with a change in the composition of vegetation from northern to middle taiga forests. According to IRSL dating, the section was formed in the MIS 10 late glacial between 330–370 ka. The two studied interstadials bracket the Likhvin (Holstein) Interglacial and sedimentary units in the Bolshaya Kosha section are proposed to have formed in MIS 9e. Full article

The formation of Quaternary glaciers represented a pivotal event in the climatic and geological history of the Tibetan Plateau. However, due to the scarcity of direct evidence for low-latitude glaciation, the timing and extent of late Quaternary glaciation on the Tibetan Plateau remain controversial. This study focuses on the Liangwang Mountains, which are located in the southeastern part of the Tibetan Plateau and has a maximum elevation of 2820 m, as the subject of investigation. Through a comprehensive application of glacial landform analysis, scanning electron microscopy (SEM)-based micromorphology analysis of quartz sand, and spore-pollen data analysis, we uncovered evident signs of glacial activity in this region during the Quaternary period. Our research identified typical glacial landforms such as cirques, U-shaped valleys, fluted moraines, and terminal moraines. Additionally, spore-pollen analysis revealed a high frequency of fir pollen, indicating cold climatic conditions during that time. Furthermore, the micromorphology analysis of quartz sand further corroborated the glacial origin of these deposits. Based on these combined findings, our study confirms that the Liangwang Mountains experienced glaciation during the Quaternary period, making them glacial relics at the lowest latitude currently known in mainland China. This discovery provides a valuable reference for understanding the paleoclimate and glacial history of the Tibetan Plateau and its surrounding regions. Full article

Reconstructing Holocene vegetation history and human impact on vegetation is critical for understanding past interactions between humans and nature. This study concentrates on the lower West River area in Southern China, offering high-resolution reconstructions of vegetation changes over the last 9000 years. Our findings reveal that during the Holocene Climatic Optimum (9–5 ka BP), the area was predominantly covered by dense evergreen broad-leaved forests. Around 5.1 ka BP, the emergence of marsh forests, as evidenced by abundant pollen of Glyptostrobus and in situ buried woods and roots, indicated a transition towards a wetland ecosystem. Notably, a thriving wetland environment and high production of peat deposits dating from 4.3 ka to 2.5 ka BP reflect the continuous drop of lake levels and the formation of swamps driven by a climatic pattern marked by decreased precipitation, potentially linked to a reduction in summer monsoon intensity during the latter part of the Holocene. This period of wetland expansion also coincides with the earliest evidence of rice cultivation in Southern China, suggesting a relationship between agricultural development and regional landscape changes. Additionally, millennial-scale paleo-megafloods are not only identified by lithological features but also by pollen taxa and principal component analysis. Despite the temporary disruptions of the marsh forest, it demonstrated resilience, quickly recovering within decades. By approximately 2.5 ka BP, a significant increase in rice-type Poaceae pollen and Pteridophyte spores, alongside the sharp decline of Glyptostrobus and a decrease in arboreal taxa, were observed. This shift in pollen spectra, coupled with a PC1 curve of principal component analysis, points to intensified human activity as a primary driver behind the collapse of the local wetland ecosystem. These findings align with regional evidence from the Pearl River Delta and coastal Southern China, highlighting extensive human intervention in natural forests and the onset of large-scale agriculture post-2.5 ka BP. Full article

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. Full article

Our study aimed to quantify the pollen trapped by the seeds and relate it with the airborne pollen concentrations. Individual Populus spp. tuft-like seeds were sampled while suspended twice a day in 2017 and 2018 during the seed dispersal season. The seeds were submitted to laboratory treatment for pollen extraction, which was quantified using an optical microscope. Airborne pollen was monitored using a seven-day Hirst-type volumetric spore sampler. A correlation analysis was performed between the airborne pollen, the pollen on the seeds, and the meteorological parameters. A total of 26 pollen grains/mg was counted in the airborne tuft-like seeds, with 26 different taxa being identified, compared with the 18 pollen taxa identified in the airborne samples. Quercus, Poaceae, Urticaceae, Pinus, and Platanus were the most frequent pollen found on the seeds, while in the atmosphere, pollen from Urticaceae, Quercus, and Cupressaceae were the most representative. A tendency of higher pollen concentrations found in the afternoon samples, both airborne and on the seeds, was observed. Correlations between the meteorological parameters and pollen concentration found airborne and in the seeds were overall not significant. Thus, airborne poplar tuft-like seeds can trap and transport pollen, most of which has been recognized to induce respiratory allergies. Full article

The objective of our work was to reconstruct transgressive-regressive events in the Northern Caspian Sea during the Khazarian epoch of its Pleistocene history to determine the natural conditions of the development of the basins and to assess their response to climate change. This work is based onstudies of the sedimentary formations of the upper part of the Quaternary sequence in the Northern Caspian Sea. The borehole was drilled in the eastern part of the depression Shirotnaya, the sea depth was 11.9 m, and the depth of drilling was 56.4 m. The core was subjected to lithological, malacological, and palynological analysis. This paper discusses the results related to the interval 56.0–26.6 m. The structure, facies-lithological, and malacological composition of the core capture three transgressive stages of the Caspian, namely the Early Khazarian, Late Khazarian, and Hyrcanian stages, separated by regressive phases. The representative spore-pollen assemblages made it possible to carry out the climatic and stratigraphic subdivision of the studied Khazarian deposits and to suggest a provisional version of the history of climatic and phytocenotic events during the sedimentation period. The results of our studies have introduced new discussion points into the paleogeography of the Northern Caspian Sea. Full article

This study explores the sedimentary environment and tectonic implications of the Upper Carboniferous Yanghugou Formation on the western margin of the Ordos Basin through the analysis of major elements, trace elements, and rare earth elements in 23 mudstone samples. The results indicate moderate chemical weathering conditions, as reflected in the Chemical Alteration Index (CIA) and Component Variability Index (ICV) values. Warm and humid paleoclimatic conditions are suggested by Rb/Sr, Sr/Cu, spore, and pollen fossil samples. The paleosalinity of the water is identified as a transitional phase of a brackish water environment based on Sr/Ba and Th/U ratios. Additionally, V/(V + Ni) and δU values imply a transitional phase of a weak oxidation–reduction environment for the water. In accordance with the La-Th-Sc, Th-Sc-Zr, Th-Co-Zr, (La/Yb)-∑REE, and (La/Th)-Hf discrimination diagrams, it is inferred that the study area is part of a continental marginal tectonic setting. The sediments are primarily derived from an upper-crust felsic source area. The sedimentary period of the Yanghugou Formation in the western margin of the basin is considered a marginal rift basin characterized by north–south compression and western rift extension. This setting is influenced by the active continental margin of the Alxa block and the passive continental margin of the Qilian–north Qinling orogenic belt. Full article