Pollen Analysis
... The utility of subfossil pollen, spores, and other palynomorphs in paleoseismic investigations was first proposed by Mathewes and Clague (1994). Although Faegri and Iversen (1989) and Moore et al. (1991), in their seminal textbooks, discuss the uses of pollen data in geology, including their value in defining marine transgressions and regressions, they did not mention possible applications in paleoseismology. The value of pollen in coastal marsh sediments to define subsidence is well illustrated by Hughes et al. (2002), who used pollen to define four marsh zones (low, middle, high, and forest-edge transition) to reconstruct coseismic subsidence of 0.5-0.69 ...
... Samples were stored in a cold room at 4 • C before processing in 2002. Subsamples of 1-2 ml (by displacement in water) were used for pollen and spore analyses using standard techniques (Faegri and Iversen, 1989;Moore et al., 1991). ...
... every 40 years) throughout the lower portion of LV4 (core depths = 463-777 cm). The samples were prepared for pollen analyses following standard procedures using HCl, KOH, HF and acetolysis (Moore et al., 1991). Lycopodium clavatum tablets (Batch number 3862 with n = 9666 ± 671 spores per tablet) provided by the University of Lund (Maher, 1981) were added to the samples prior to chemical treatment in order to calculate microfossil concentrations and influx (Stockmarr, 1971). ...
... The physical and chemical extraction of non-pollen palynomorphs was carried out using standard palynological techniques modified from Traverse (1988), Faegri and Iversen (1989), Moore et al. (1991), and Wood et al. (1996). Palynological treatments were conducted at the Northeastern Research Institute of Petrified Wood and Mineral Resources (In Honour of His Majesty the King), Nakhon Ratchasima Rajabhat University, Thailand. ...
Fungal spores in Neogene organic-rich sediments from the Hongsa coalfield in northwestern Lao PDR were studied in detail. Fungal spores and the significance of palynological associations are employed for interpreting depositional environment and paleoclimate. The palynological assemblages, recovered from 34 samples, were rich and diversified, consisting mainly of pollen grains of vascular plants, spores of pteridophytes, and fungal spores. Of all 67 fungal taxa from 22 genera identified in this study, 21 are Amerosporae, 20 Phragmosporae, 18 Didymosporae, and 8 Dictyosporae. Although diversified, they yielded low to very low frequencies compared to total palynomorphs. Most palynological and fungal spores in this investigation indicate a Miocene age of the deposits. The presence of Dyadosporites, Brachysporisporites, Diporicellaesporites, Pluricellaesporites, and Dictyosporites of subtropical to warm temperate forests associated with a large number of pteridophytes and evergreen to deciduous vegetation can reinforce the hypothesis of terrestrial origin in a humid and warm climate. Variations in relative abundance and diversity of fungal spores in this study indicate paleoenvironmental fluctuations during deposition, which also conform to the climate interpreted from each palynological zone.
... To enable calculation of pollen, NPPs and charcoal concentrations, an exotic marker, i.e., a Lycopodium tablet with a known concentration of spores (Stockmarr, 1971) was added to the samples before treatment. Identification of pollen and plant spores followed standard keys (Moore et al., 1991;Beug, 2015). NPP identifications were carried out as in van Geel, 1978;van Geel and van der Hammen, 1978;van Geel et al., 1983;Jankovská and Komárek 2000;Komárek and Jankovská 2001;Carrión and Navarro, 2002;Fugassa et al., 2006;Montoya et al., 2012;Barthelmes et al., 2012;Prager et al., 2012;Kołaczek et al., 2013;Dietre et al., 2014;López-Vila et al., 2014;Shumilovskikh et al., 2016;Schlütz and Shumilovskikh, 2017;and Roche et al., 2020. ...
The aim of the present paper is to discuss the application of phytolith (microbiomorphic) and non-pollen palynomorph (NPP) analyses to the geoarchaeological study of a Medieval – Early Modern Time period
farmyard in Graft, a settlement located in the polder region of North Holland, the Netherlands. The authors have assessed the potential of the methods chosen for studying this type of archaeological site during rescue excavations, when archaeologists often have a limited number of samples or methods for
geoarchaeological analysis. The studies conducted have proved the informative value and effectiveness of microbiomorphic and NPP analyses in rescue excavations, especially when applied in combination, thus providing controlling and complementary information for each analysis. The data obtained have provided an important insight into the archaeological interpretation of the cultural layer within the farmyard. In addition, more information was gained on the local palaeoenvironmental dynamics and the phases of economic activity at the farmyard during the 13th–17th centuries CE.
... Los concentrados de polen se prepararon en tres muestras para completar y replicar los resultados anteriores. La preparación siguió el método estándar, incluyendo un tratamiento químico y una separación mineral por líquido denso (Moore et al., 1991). Los posibles efectos de percolación del polen en este tipo de registros no se conocen bien, pero algunos autores cuestionan el uso del polen para datar sondeos de hielo (Ewing et al., 2014), mientras que otros lo dan como método válido (Festi et al., 2017). ...
En este trabajo se presenta el reto que muchas veces supone conseguir un buen modelo de edad independiente en una secuencia paleoambiental. Esta aproximación pasa por la necesidad de combinar diferentes metodologías de datación, con la complejidad que esto implica. Se han seleccionado dos ejemplos de dos archivos paleoambientales muy distintos, y con cronologías muy diferentes. El registro de El Cañizar de Villarquemado, un paleolago en la provincia de Teruel, que alberga en sus sedimentos los últimos 135.000 años de historia y constituye la secuencia continental más larga y continua estudiada en la mitad septentrional de Iberia. Para poder establecer un modelo de edad robusto e independiente fue necesario combinar dataciones de radiocarbono AMS, U-Th, OSL, IRSL, paleomagnetismo y criptotefro-cronología, aunque no todas las técnicas resultaron exitosas. El segundo ejemplo se centra en el reto de datar el hielo presente en el icónico glaciar de Monte Perdido, situado en el Pirineo Central, Huesca. Este registro se consiguió datar mediante radiocarbono en diferentes tipos de muestras y aplicando las técnicas de 210Pb y 137Cs para el periodo más reciente. En ambos ejemplos, las combinaciones de métodos y tipo de muestras datadas permitieron obtener cronologías robustas gracias a una importante inversión de tiempo y financiación, siendo el resultado de la colaboración de varios equipos de investigación. En este trabajo se esbozan las dificultades encontradas en la elaboración de ambas cronologías y se presenta el resultado final, fruto de una modelización que combina las diferentes aproximaciones para obtener los modelos de edad definitivos.
... Pollen morphological studies proved to be indispensable for the understanding of evolutionary processes and systematics (Persson et al., 1996;Carlo and Paula, 2004).The ability to identify plants from their pollen has enabled botanists and ecologists to reconstruct past assemblages of plants and identify periods of environmental change (e.g., Faegri and Iversen, 1989;Moore et al., 1991). Research into the morphological characteristics of pollen grains by scanning electron microscopy (SEM) of specific genotypes and cultivars are important and useful for taxonomy, palaeobotany, phylogeny, breeding programmes, e.g. ...
The studying of Castanea sativa Mill. pollen allows us to determine the details of morphological characteristics and described the most important parameters and pollen sculpture that can be used to identify representatives of species.
The general characteristics and significant morphological traits of pollen grains of 16 genotypes Castanea sativa Mill. collected from M.M. Gryshko National Botanical Garden of Ukraine(Kyiv) were observed via a scanning electron microscope (SEM). The measurement of morphometric parameters was carried out on 50 pollen grains from each
genotype using the AxioVision Rel. 4.8.2.0 program. The length of the polar axis (P) and the equatorial diameter (E) of grain, P/E ratio were measured and their variation was compared among studied genotypes. SEM investigations showed that the pollen grains of Castanea sativa are small-sized, the equatorial view is elliptic, the polar view is angular,
with convex mesocolpia, more or less circular. This study showed the small differences between the genotypes in all measured factors. The average polar axis and equatorial diameter of pollen grains values varied in the interval 19.10 ±0.21–20.53 ±0.21 and 8.86 ±0.05–9.85 ±0.08, respectively. We determined the variation coefficient in the range of
3.37–8.93 %. It was noted that diversity of surface sculpturing of pollen grains in combination with shape and sizes enables to use of a complex of thin morphological signs for Castanea sativa pollen identifications.
Pollen grain structure is one of the diagnostic taxonomic and phylogenetic parameters. Study of morphology and morphometry of pollen grains of Amelanchier spp. allows found new additional diagnostic parameters of species. We determined that pollen of Amelanchier spp. is variable both in size and morphology. SEM investigations showed that the pollen grains various species of Amelanchier are prolate and perprolate, the surface sculpture and shape index of the species vary. The average length of the polar axis varied from 27.38 to 47.14 μm and the width of the equatorial axis was in the range from 14.33 to 28.95 μm. Shape index (P/E) of tested species varied from 1.77 to 2.09. The most average length of pollen was Amelanchier spicata (43.24 μm) and the least length was Amelanchier arborea (13.69 μm). The most average width pollen was Amelanchier canadensis (23.04 μm), and the least width was Amelanchier arborea (16.07 μm). Cluster analysis showed that the relationships of the tested Amelanchier species according to morphological features are represented by two main groups. It is evidently that A. arborea which has the smallest parameters is really separated from other species. A. lamarki, A. spicata and A. canadensis are similar according to morphometric sizes. Studies via scanning electron microscope have established characteristic differences in the morphometric and microsculptural features of pollen for each of the studied Amelanchier spp. which can be used to identify the representatives of species. Differences in the size of pollen grains in comparison with other authors may be the result of many environmental factors specific to the geographical area, climatic conditions of the country such as constantly increasing atmospheric temperature, alternation of rainfall with a dry season and others, which could be the subject of further research.
Upland moorlands are important landscapes, but many are considered degraded as a result of human activities. Consequently, their protection and restoration are of substantial concern. In Europe, restoration activities are often aimed at reversing the effects of 19th and 20th century “agricultural improvements,” which often involved major drainage schemes. However, the ecological effects and long-term ecological context of “agricultural improvement” are not yet fully understood. To develop this understanding, we analyze paleoecological data (pollen, coprophilous fungal spores, microcharcoal) from five upland peatland sites using a range of analytical approaches: cluster analysis, principal component analysis, rate-of-change analysis, and regression analyses incorporating documentary historical data. The sites are located on Exmoor (South West England, UK), a landscape that typifies historic upland degradation. We demonstrate that in this landscape, 19th century drainage is associated with declines in Sphagnum and non-arboreal taxon richness; over longer timescales burning is associated with enhanced graminoid monocot abundance and grazing with lower taxon richness. We also show that rate-of-change in moorland vegetation communities during the 19th century is not distinctive in a long-term context: change has been a constant in this landscape, rather than an exception during the 19th century. Our findings indicate that the aims of “restoration” interventions intended to increase Sphagnum abundances, increase taxon richness and reduce graminoid dominance are consistent with the long-term dynamics of peatland systems, such as those on Exmoor. “Restoration” deemed successful in these terms may or may not resemble pre-drainage conditions, which were themselves a function of millennia of successive moorland management regimes.
Investigations at Oak Tree Fields, Cerney Wick, Gloucestershire, in western England have revealed a sequence of fluvial deposits dating from Marine Oxygen Isotope Stage (MIS) 7 to 5. At the base of the sequence, a series of gravel and sand facies were deposited, initially as part of a meandering river. Reductions in flow energy of the latter and avulsion led to the development of short‐lived channels and episodic backwater environments, the deposits of which are recorded as Facies Associations 1–3. Poorly sorted, probably colluvial deposits formed beyond the limit of the channel (Facies Association 4). Mollusca, Coleoptera, plant macrofossils, pollen and vertebrates recovered from the channel facies indicate broadly similar climatic conditions throughout accretion. Temperature ranges derived from mutual climatic range analysis of the Coleoptera almost completely overlap with those of Cerney Wick at the present day, albeit that winters may have been cooler when the channel was active. Further, the floral and faunal data suggest that the meandering river flowed through an open grassland environment, the latter heavily grazed by large vertebrates, most notably mammoth. Most of the botanical and faunal remains, together with four optically stimulated luminescence (OSL) age estimates ranging from 225 ± 23 to 187 ± 19 ka, suggest correlation of the channel deposits with MIS 7. The basal deposits (Facies Association 1) yielded the majority of vertebrate remains and all the lithic artefacts, most of which seem likely to have travelled only a short distance. Although only a few artefacts were recovered, they add to the relatively limited evidence of human activity from the upper Thames. The channel deposits are overlain by sheet gravels (Facies Association 5) which are attributed to the Northmoor Member of the Upper Thames Formation. These were likely to have been deposited as bedload in a braided stream environment, while two OSL age estimates of 129 ± 14 and 112 ± 11 ka suggest accumulation during MIS 5.
The ~25.5‐ka Ōruanui supereruption (Taupō volcano, New Zealand) erupted >1100 km3 of pyroclastic material during the Last Glacial Maximum. The impacts of this event on climate and the New Zealand environment remain unresolved, particularly on ecological timescales. Using sediment cores from Onepoto maar palaeolake, Auckland (~240 km upwind from source), we have analysed pollen assemblages at contiguous 1‐mm intervals, around an intact 3‐cm layer of the Kawakawa‐Ōruanui Tephra to resolve and assess post‐eruption vegetation impacts and landscape recovery. Sediments immediately above the tephra record a decline in the relative abundance of the dominant canopy species of Fuscospora, and concurrent increase in the abundances of grasses, herbs, ferns and shrubs. These changes reflect a brief (<10 years) part‐defoliation of canopy trees, permitting more light to penetrate and to encourage sub‐canopy vegetation growth. A short‐lived volcanogenic cooling inferred from Antarctic ice core records may have contributed to the changes but cannot be separated from the immediate and direct ecological impacts of ashfall on vegetation following the eruption. Our results, here applied to the world's most recent supereruption, more generally demonstrate the value of millimetre‐scale stratigraphic pollen analysis from non‐varved lacustrine sediments as a tool for assessing past eruptive impacts on sub‐decadal timescales.
(1) Ombrotrophic peat bogs provide valuable records of environmental change on long timescales but are rarely preserved near the major centers of industrial activity. Holcroft Moss is a rare example of a stratigraphically intact lowland peat bog in NW England, which provides a valuable opportunity to trace industrial impacts on vegetation in a sensitive environmental archive close to the early industrializing cities of Manchester and Liverpool. (2) We reconstructed environmental changes at Holcroft Moss before and after the Industrial Revolution using a decadal‐scale record of pollen, non‐pollen palynomorphs, microcharcoal, peat composition (organic content and ash‐free bulk density) and heavy metal content, constrained by a radiocarbon and SCP (spheroidal carbonaceous particle) chronology. We examine the relationship between abiotic and biotic environmental tracers using principal component analysis and evaluate the role of local and regional climatic and anthropogenic drivers using canonical redundancy analysis and partitioning of variation. (3) Results show significant changes in bog vegetation composition during the last 700 years. Prior to 1750 CE, climate and agro‐pastoral activity (grazing and fires) were the main drivers of vegetation change. Subsequently, regional coal‐fired industry contributed to major increases in atmospheric pollutants (dust, heavy metals, and acid deposition) that severely impacted vegetation, driving the decline of Sphagnum. Grasses rose to dominance in the 20th century associated especially with bog conversion and cumulative nitrogen deposition. Although atmospheric pollution significantly decreased in the post‐industrial era, vegetation has not returned to pre‐industrial conditions, reflecting the ongoing impact of global change drivers which pose challenges for conservation and restoration. (4) Synthesis. Paleoecological studies are needed to reveal the long‐term history of vegetation degradation and to offer guidelines for restoration and conservation practices. This study reconstructs the last 700 years of a peat bog located between Manchester and Liverpool, revealing the timing and nature of vegetation changes across the trajectory of early industrialization and eventual post‐industrial decline. Our study reveals the progressive dominance of regional anthropogenic forcing and highlights that the present‐day vegetation does not have past analogs within the last 700 years. Conservation measures favoring the reintroduction of Sphagnum are justified in redressing the major biological legacy of the Industrial Revolution, while steps to increase Calluna should also be considered in light of its resilience to dry and fire‐prone conditions. This study presents the last 700 years of a peat bog located between Manchester and Liverpool, revealing the timing and nature of vegetation changes across the trajectory of early industrialization and eventual post‐industrial decline.
There are two main ways in which human impact on vegetation has been conceptualized using pollen data. First, the action of humans on vegetation is to reduce the extent of tree cover, under the assumption that tree clearance equates to the conversion of land for agricultural activities or is a consequence of pre‐agrarian disturbance regimes such as fire. Second, humans alter the compositional makeup of vegetation, through deliberate selection or unforeseen consequences of land use. A complementary method to the landscape reconstruction algorithm is the Multiple Scenario Approach. This approach also relies on a detailed understanding of relative pollen productivity and pollen dispersal models but takes as its starting point maps, or scenarios, of vegetation cover in the past. The ability to identify pollen grains to a high taxonomic level, and thus provide a more detailed evidence base for reconstruction of human impacts, has been, and remains, a significant challenge.
Pollen analysis has been a key technique for attempting to understand the environmental context of archaeological sites since the middle of the twentieth century. This chapter considers pollen and macroscopic plant remains, with a focus on their differing properties in terms of dispersal, preservation, quantification, and so on. Pollen may be preserved in a variety of archaeological contexts, of which the most suitable are those that are permanently waterlogged. Macroscopic plant remains are those which are visible to the naked eye, although their precise identification often requires use of a microscope. Macroscopic plant remains are often found in similar contexts to pollen, especially on waterlogged archaeological sites and in ‘off‐site’ contexts such as lakes and mires, where they may be hugely abundant and indeed form the bulk of the sediment matrix.
Lake and peat sediments are frequently used to reconstruct palaeoclimate records from all continents using a variety of proxy techniques. This chapter explores the advances that have occurred in the last 20 or more years for using lake and peat sediments to reconstruct past climate change. It demonstrates the impact these advances have had for palaeoclimate research, and implications for archaeology. Fossilized insect remains are often abundant in a wide range of sediments, including lake, river, and peat deposits. Fire is a natural disturbance in many ecosystems, and lake sediments often contain charcoal that can be used to infer fire dynamics. Ombrotrophic bogs have accumulated deep peat deposits throughout the last 10 000 years in temperate latitudes and elsewhere around the world. The chapter focuses on the research that underpins estimates of past palaeoclimate variability as inferred from peatlands.
Previous palaeoenvironmental reconstructions have implied that East Asia was dominated by a zonal climate pattern during the Eocene, with an almost latitudinal arid/semiarid band at ~ 30° N. However, this long-standing model has recently been challenged by growing body of multidisciplinary evidence. Some studies indicated that central China was characterized by climatic fluctuations between humid and drier conditions during the Early Eocene, akin to the present East Asian monsoon (EAM) regime. Using palynological assemblages in the Tantou Basin, central China, we quantitatively reconstructed climate changes from the Late Palaeocene to Early Eocene to better understand climate change in central China. Palynological assemblages revealed that the coniferous and broad-leaved mixed forest in this area received no less than 800 mm of annual precipitation and experienced a climate change from warm and wet to relatively cool and dry. According to palaeoclimate curves, a sudden climate change occurred in the Early Eocene, with the mean annual temperature and precipitation decreasing by 5.1 °C and 214.8 mm, respectively, and the climate became very similar to the present climate, which is controlled by the monsoon. Therefore, this significant climate change during the Early Eocene may signal the emergence of the EAM in East Asia.
Grotta Mora Cavorso (Jenne, Latium), a complex karstic system in Central Italy, has returned one of the most precious Prehistoric palaeontological and anthropological heritage. Through the analysis of pollen spectra and charcoals from cave stratigraphic levels (Late Pleistocene final phases—Holocene), the overall vegetation trend of the site was pointed out. Although taphonomy and palynology of cave deposits are complex, pollen assemblage represents a reliable source for inferring past vegetation; indeed, climatic, environmental, and cultural interactions determine fossil pollen record. Site formation processes and postdepositional bias should be generally considered in the analysis of stratigraphic sequences used to define paleoenvironmental conditions. The sediment deposits from Grotta Mora Cavorso showed a vegetation pattern point in out a progressive increase in woody plants from lower levels upward. Palynological investigations highlighted a changing environment predominantly characterized by cooler and perhaps more humid conditions than today, with plant subalpine and marsh communities nearby the cave. The ecological requirements of the identified plant taxa supplied useful indications to reconstruct ancient and modern environments of the Simbruini Mounts and the Upper Aniene River valley. This scenario, in accordance with previous faunistic and carpological findings and palynological analyses from Latium, provided a further perspective on the vegetation history, biodiversity, and climate of an important crossroads between the Adriatic and the Tyrrhenian coasts. A palynological study from the sediment deposits of Mora Cavorso Cave is presented. The stratigraphic layers dated back from the Late Pleistocene to the entire Holocene. Pollen analysis revealed a changing environment in the upper Aniene River Valley. An important perspective on the vegetation profile of a valuable prehistoric site was provided.
The profile of the Lipowo palaeolake (NE Poland) preserves a record of environmental and climate changes from the Last Glacial Termination (16.5k cal ka BP), stretching from the Oldest Dryas to the youngest Allerød warm oscillation. In this interdisciplinary study of the lacustrine succession at Lipowo, we used biological and geochemical indicators and multiproxy analyses to reconstruct environmental changes in the lake ecosystem, such as mollusc, zooplankton and vegetation development, trophic state, water temperature and water level. Four cold and four warm climate oscillations of different durations were identified on this basis: the Older Dryas climate deterioration and two short‐term coolings within the Allerød Interstadial, separated by warm periods in the Bølling and Allerød. The covering of the lake series by diamicton deposits from the melting of dead‐ice blocks is a particularly interesting and rare phenomenon for a postglacial area. The hydrological system of the catchment was generally closed, with a periodically opening and existing flow‐through lake. Over the period of the lake's existence, vegetation changed in general from steppe tundra to forest with birch and pine. For most of this time, the palaeolake was mainly oligotrophic, with increased productivity and a higher trophic level only notable during the middle Bølling.
Aim
Pinewood decline and scrubland expansion are major features of Late Holocene vegetation history in the Cantabrian Range. However, the drivers of this remarkable vegetation shift remain to be investigated. Here, we aim at disentangling the role of past land use and climate in shaping the high‐elevation Cantabrian landscape during the past two millennia.
Location
Cantabrian Range (northern Iberia).
Taxa
Pinus sylvestris , Betula , Ericaceae, Juniperus , Poaceae.
Methods
We conducted high‐resolution multiproxy palaeoecological analyses (pollen, plant macrofossils, microscopic charcoal and dung fungi) on lake sediments from Lago del Ausente to reconstruct vegetation, fire occurrence and grazing through time. The chronology is based on ¹⁴ C (terrestrial plant macrofossils) and ²¹⁰ Pb dating, and Bayesian age‐depth modelling (‘rbacon’). We carried out cross‐correlation analysis to quantify vegetation responses to fire.
Results
Between 250 and 900 CE, the vegetation above 1700 m a.s.l. consisted of subalpine scrubland and scattered P. sylvestris trees/stands. Pinewoods with Betula were widespread at slightly lower elevation. This vegetation was resilient to moderate fire disturbance associated with limited pastoral activities. In contrast, enhanced fire occurrence alongside heavier pastoralism led to the demise of pinewoods and their replacement with Betula stands, subalpine scrublands, and meadows between 900 and 1100 CE. Later, the subalpine scrubland‐birch tree line did not respond to Little Ice Age cooling. However, further intensification of transhumant herding between 1300 and 1860 CE (‘La Mesta’) triggered birch decline and the establishment of the modern treeless landscape.
Main conclusions
The extant high‐elevation vegetation of the Cantabrian Range is largely the legacy of intensive land use starting more than one millennium ago. Recurrent and severe fires to promote pasturelands led to the regional extirpation of the previously widespread Pinus sylvestris . Future management should aim at preserving the valuable cultural open landscape of mountain scrubland and meadows and also at restoring patches of ancient pine‐birch woodlands.
Large amounts of carbon in alpine sediments have been expected to be sensitive to climate change, but how carbon accumulation responds to climate change remains unclear. Thus, we explored the impact of different factors on the carbon accumulation rate (CAR) of alpine sediments by combining a variety of climatic variables, vegetation data and erosion indicators based on two alpine sediment successions on Taibai Mountain, the highest peak in central and eastern mainland China. One succession is near the modern treeline (Paomaliang Swamp, PML) and the other is located at the upper forest line (Sanqing Chi, SQC, a small lake). We used our previously published organic carbon content data and for the first time calculated the CAR, and further used pollen and physicochemical indicators to quantify the contributions from climate, vegetation and soil. We found that their contributions varied during different periods and between the two sediment successions. For the PML succession, from 5850 to 4000 calendar years before present (cal. a BP), the CAR was low, which was related to low annual temperatures, low vegetation cover and strong soil erosion. From 4000 to 2400 cal. a BP, a high CAR coincided with high annual temperatures, high vegetation cover and weak soil erosion. From 2400 to 200 cal. a BP, the CAR decreased, mainly attributed to low vegetation cover. Local vegetation cover had major impacts on the CAR in the SQC succession during the Middle–Late Holocene. In general, the local factor interpretation rate in SQC (83%) was higher than that of PML (47%), related to the vegetation stability of continuous forest and the treeline. This study highlights the important role of the local environment in determining carbon accumulation in the alpine region.
Pronounced glacial and interglacial climate cycles characterized northern ecosystems during the Pleistocene. Our understanding of the resultant community transformations and past ecological interactions strongly depends on the taxa found in fossil assemblages. Here, we present a shotgun metagenomic analysis of sedimentary ancient DNA (sedaDNA) to infer past ecosystem-wide biotic composition (from viruses to megaherbivores) from the Middle and Late Pleistocene at the Batagay megaslump, East Siberia. The shotgun DNA records of past vegetation composition largely agree with pollen and plant metabarcoding data from the same samples. Interglacial ecosystems at Batagay attributed to Marine Isotope Stage (MIS) 17 and MIS 7 were characterized by forested vegetation (Pinus, Betula, Alnus) and open grassland. The microbial and fungal communities indicate strong activity related to soil decomposition, especially during MIS17. The local landscape likely featured more open, herb-dominated areas, and the vegetation mosaic supported birds and small omnivorous mammals. Parts of the area were intermittently/partially flooded as suggested by the presence of water-dependent taxa. During MIS 3, the sampled ecosystems are identified as cold-temperate, periodically flooded grassland. Diverse megafauna (Mammuthus, Equus, Coelodonta) coexisted with small mammals (rodents). The MIS 2 ecosystems existed under harsher conditions, as suggested by the presence of cold-adapted herbaceous taxa. Typical Pleistocene megafauna still inhabited the area. The new approach, in which shotgun sequencing is supported by metabarcoding and pollen data, enables the investigation of community composition changes across a broad range of taxonomic groups and inferences about trophic interactions and aspects of soil microbial ecology.
Precipitation is a key climate parameter of vegetation and ecosystems in the Iberian Peninsula. Here, we use a regional pollen–climate calibration model and fossil pollen data from eight sites from the Atlantic coast to southern Spain to provide quantitative reconstructions of annual precipitation trends and excursions and their regional patterns for the last 11 700 years. The Early Holocene (11 700 to 11 000 cal. a BP) was characterized by high precipitation values followed by a slowly declining trend until about 9000 cal. a BP in the south and about 8000 cal. a BP in the north. From 8000 to 6000 cal. a BP the reconstructed precipitation values are the highest in most records, especially in those located in the Mediterranean climatic region in the southern part of the peninsula, with maximum values nearly 100% higher than the modern reconstructed values. The results suggest a declining precipitation during the Late Holocene in the south, with a positive excursion at around 2500 cal. a BP, while in the north precipitation remained high until 500 cal. a BP. However, the Late Holocene climate reconstructions in the Iberian Peninsula are biased by intensifying human impact on vegetation. The statistical time series analyses using SiZer technique do not indicate any statistically significant high‐frequency drought events in the region. In general, our results suggest regional differences in the precipitation patterns between the northern and southern parts of the peninsula, with a more distinct Middle Holocene period of high humidity in the south.
Predicting the effects of ongoing climate warming on vegetation requires a long‐term perspective of past ecosystem dynamics. We therefore analysed the sedimentary record from the mire Gola di Lago (985 m a.s.l.) in southern Switzerland, to better understand the vegetation response to past rapid climate change. We present a high‐resolution pollen and plant macrofossil study from the Lateglacial to the Early Holocene (13 400–10 400 cal. a BP), a climatic transition that represents a close analogue to current global warming. The vegetation responses during this time match previously analysed palaeoecological sites south of the Alps. At the end of the Bølling‐Allerød interstadial, the site was surrounded by open larch forest. The beginning of the Younger Dryas was characterized by the local presence and rapid expansion of Pinus cembra, whereas the second part was dominated by Pinus sylvestris, Betula and Larix decidua. These vegetation dynamics agree well with independent climate data indicating a cold and dry start and a subsequent shift to slightly warmer climate. The following rapid temperature increase at the beginning of the Holocene resulted in an increase in forest density and the establishment of novel temperate vegetation assemblages, without major changes in species diversity. Noteworthy, during the Younger Dryas–Early Holocene transition, long‐lived cold‐adapted tree line species such as P. cembra and L. decidua persisted over several centuries, while open boreal forests dominated by P. sylvestris and Betula expanded, indicating high resilience to climatic changes. The results of Gola di Lago suggest that climate warming led to a significant change in vegetation communities through species range shifts. Our study also indicates that some species may potentially be able to locally persist under current global warming, forming novel vegetation assemblages with newly establishing species.
Palyno-anatomical characterization of some selected species of Boraginaceae and Fabaceae using light microscopy (LM) and scanning electron microscopy (SEM) was conducted. Six species of them belongs to four genera of family Boraginaceae and other six species belongs to four genera of Fabaceae. The current study aimed to investigate palyno-anatomical features for correct identification and taxonomic significance. Pollen grains were acetolyzed and observed both qualitatively and quantitatively through light microscopy and scanning electron microscopy. Statistical data was analyzed through cluster analysis which categorized plants into clusters. Principal component analysis (PCA) was carried out to illustrate morphological variation among selected plant species. Studied plant species showed variation in shape, size, aperture type, exine ornamentation of pollen, size and shape of epidermal cells, types of stomata, guard cells, subsidiary cells and trichome types. Exine thickness was recorded maximum 2.30 ± 0.1 μm in Lablab purpureus and minimum 1.05 ± 0.2 in Gastrocotyle hispida. PCA summarized 73.78% of accumulative variance. Trichome index was observed highest 62% on the adaxial surface of Heliotropium europaeum and lowest 21% on adaxial surface of L. purpureus. These findings reinforce the importance of palyno-anatomical features in the characterization and identification of taxa. It was concluded that description of palyno-anatomical characteristics presented in this study, highly contribute to our knowledge for correct identification of plant species.
Palynological features of tribe Astagaleae L. have been observed with scanning electron microscopy (SEM), to assess features that can be used to re-examine the placement and taxonomic position of tribe. The palynomorph attributes of 10 species included in three genera of Astragaleae (Astragalus L., Glycyrrhiza L., and Oxytropis DC.) are investigated. The assignment of genus Oxytropis in tribe Astragaleae was also reevaluated based on pollen characters. Pollen appear to be prolate, prolate-spheroidal, and subprolate. Polar axis size (P) varies from 31.3 μm ±1 to 17.5 μm ±1.4 and equatorial axis size (E) varies from 22.2 μm ±1.8 to 13.1 μm ±0.9. Prominent apertures found consistently dispersed along the surface of pollen. Three kinds of ornamentation pattern were recorded, that is, reticulate or reticulate-perforate and perforate. The studied species display variation in equatorial and polar diameter, aperturation and sculpturing pattern, exine thickness, and pollen shape. On the basis of descriptive pollen features, a dichotomous taxonomic key and UPGMA analysis has been made for effortless and quick identification. The study concluded that disparities of the entire features are typically unrelenting and concerned with the species and shows potential systematic significance. The combination of palynological attributes in association with additional traits has prospective for systematic identification at species and genus level.
The pollen morphology, with special reference to exine sculpture, of some species of the gymnosperms was assessed for the first time from the subalpine and alpine zones of western Himalayas northern Pakistan. The pollen of all these species is airborne and allergenic, so pollen morphology helps for identification of this allergenic pollen at specific level. Different morpho-palynological characteristics were analyzed including size range of pollen, polar and equatorial diameter ratio, exine ornamentation, sculpturing, exine thickness, pollen type, and shape. For accurate and quick identification of species, taxonomic key was made based on different morpho-palynological characteristics. The quantitative data were processed using SPSS software. Gymnospermal pollen includes inaperturate, rarely 1-colpate observed in (Cupressaceae), hexazonocolpate in (Ephedraceae), vesiculate, bissacate in (Pinaceae), and inaperturate in (Taxaceae). Different pollen shapes observed were prolate (4 spp), sub-spheroidal (7 spp), and oblate (1 spp). Variation was observed in exine sculpturing granular (4 spp), reticulate (1 spp), areolate-punctate (3 spp), and psilate (2 spp). This is based on the analysis of 10 plants belonging to four families of gymnosperms. Distinct pollen shape has emerged as the most diagnostic feature to separate some genera such as spheroidal in (Cupressaceae, Taxaceae), prolate and radiosymmetrical in (Ephedraceae), and bilateral in (Pinaceae). Exine thickness and sculpturing proved to be helpful at generic and specific levels. The results reinforced the significance of gymnospermal pollen morphological features which were used as aid for valuable taxonomic tool in plant systematics.
We present results from a palaeoecological analysis conducted on deposits accumulated in an oxbow lake of the Prosna River (Poland), next to the Grodzisko fortified settlement. Palaeobotanical and geochemical analyses—supported by radiocarbon dating—were performed to (i) reconstruct palaeoenvironmental conditions of the oxbow lake and its surrounding area; (ii) determine the beginning of the human activity in the fortified settlement vicinity; and (iii) assess the impact of human pressure on the environment. The Grodzisko fortified settlement was originally located on a river island, encircled by a wetland, improving its defensive value. Increases in the water level (1800–1300 BC and 700–200 BC) created a small lake/moat around the fortified settlement. Indicators for human activity from pollen records suggest the presence of human populations from the late Neolithic, ca. 2800 BC, with a clear intensification ca. 1700 BC. From ca. 1600 BC, a decrease in some decidous trees suggests forest clearance. Low levels of human activity indicator pollen ca. 2000 BC suggest a reduction of human pressure (possible depopulation). The regular presence of macrocharcoal pieces and an increase in human activity indicator pollen from ca. 1300 to 200 BC provide evidence for renewed human habitation around the sampling site.
The paper studies sediments from Lake Tikozero that have accumulated successively in the littoral of Lake pre-Imandra, Imandra lagoon, and an open lake isolated from a parental freshwater body. The ‘Apatity’ bog was concurrently formed on the Lake Imandra coast. Lithological, ¹⁴C, pollen and diatom data and findings of previous investigations provide the regional Holocene stratigraphy, which is subdivided into the early (c. 11 550–8200 cal a bp), middle (c. 8200–4000 cal a bp) and late (last 4000 cal a bp) Holocene sub-stages. In the early Holocene, environments became favourable for diatoms after c. 9700 cal a bp. Birch phytocoenoses and pine forests with birch flourished in the area. In the middle Holocene, the west-central Kola Peninsula was covered by a pine-birch forest with alders. Lake Tikozero became shallow and desiccated in a warm and dry climate between c. 6300 and 4000 cal a bp; and a Sphagnum raised bog developed in the adjacent area, provoked by lowering of the water table. Spruce appeared in a pine-birch forest and indicates a colder and wetter climate in the late Holocene. The flooding of Lake Imandra created a number of new small lakes; and fens occurred along the wet shores.
Lake-level reconstructions are a key tool in hydro-climate reconstructions, based on the assumption that lake-level changes primarily reflect climatic changes. Although it is known that land cover changes can affect evapotranspiration and groundwater formation, this factor commonly receives little attention in the interpretation of past lake-level changes. To address this issue in more detail, we explore the effects of land cover change on Holocene lake-level fluctuations in Lake Tiefer See in the lowlands of northeastern Germany. We reconstruct lake-level changes based on the analysis of 28 sediment records from different water depths and from the shore. We compare the results with land cover changes inferred from pollen data. We also apply hydrological modelling to quantify effects of land cover change on evapotranspiration and the lake level. Our reconstruction shows an overall lake-level amplitude of about 10 m during the Holocene, with the highest fluctuations during the Early and Late Holocene. Only smaller fluctuations during the Middle Holocene can unambiguously be attributed to climatic fluctuations because the land cover was stable during that period. Fluctuations during the Early and Late Holocene are at least partly related to changes in natural and anthropogenic land cover. For several intervals the reconstructed lake-level changes agree well with variations in modelled groundwater recharge inferred from land cover changes. In general, the observed amplitudes of lake-level fluctuations are larger than expected from climatic changes alone and thus underline that land cover changes in lake catchments must be considered in climatic interpretations of past lake-level fluctuations.
In this study, we analysed a ˜54‐m sediment core consisting of Quaternary sediments overlying the Neoproterozoic Muhos Formation in central western Finland, adjacent to the Gulf of Bothnia. The sediments recovered were logged, and their sedimentological characteristics defined. Two fine‐grained sediment units were subjected to biostratigraphical studies using pollen and diatom analyses. In addition, two sand‐rich units and a wooden stick were dated by the optically stimulated luminescence (OSL) and 14C‐AMS methods. The core sediments were divided into six units, where several diamicton, sand and gravel, and silt‐and‐clay‐dominated beds were studied. The results indicate that the sediment succession of the core beneath the Holocene Litorina Sea and the Ancylus Lake sediments of the Baltic Basin were deposited in glacial and lacustrine environments that existed in the Oulu River valley during the time period between the Saalian glaciation (MIS 6) and the Holocene. The stratigraphical evidence, supported by the OSL ages, suggests that the Scandinavian Ice Sheet (SIS) entered the Muhos area during the Saalian glaciation, and at least during three separate time intervals in the Weichselian stage. Stratigraphically controlled and age‐bracketed evidence shows that the first Weichselian SIS advance extended further south in the eastern part of Fennoscandia than previously estimated, and that this ice growth phase occurred during the Early Weichselian Herning Stadial (MIS 5d). The subsequent ice growth phases occurred during the Middle (MIS 4) and Late (MIS 2) Weichselian substages. The lacustrine and littoral sediments of the Muhos core were correlated with the late Eemian interglacial (MIS 5e) and two Weichselian interstadials (MIS 5c and MIS 3).
The intertidal environment of the Ponzos beach (NW Iberian Peninsula) hosts a sedimentary sequence (including large wood fragments) deposited during the first half of the Holocene in a hygrophilous continental wetland. Pollen and macrofossil data alongside radiocarbon dating allow reconstruction of the changes that occurred during the Early and Middle Holocene in the landscape of the NW Iberia coastal lowlands, as well as the local wetland plant communities, in response to the climate variations and the eustatic sea‐level oscillations. The sequence represents the evolution of a coastal wetland from its initial phases as a hygrophilous wetland towards the subsequent installation of a freshwater lagoon. Pollen data show the dominant role of Atlantic (mainly deciduous) woody taxa, the scarcity of conifers and the lack of Mediterranean elements in the coastal landscapes around the Ponzos site. The presence and abundance of some taxa such as deciduous Quercus, Castanea, Fagus, Tilia and Ulmus during the Early Holocene provides further support for the occurrence of glacial refuges in the Cantabrian‐Atlantic area during the Last Glaciation. The diverse vegetation that characterizes the modern landscapes in this territory established later, spreading from these glacial reservoirs of biodiversity. In this sense, the notable and early presence of Fagus at the beginning of the Holocene, a tree also previously recorded during several phases of the Last Glacial Cycle on the NW Iberia coasts, is noteworthy. In addition, during the Early and Middle Holocene are recorded other trees that are currently extirpated as natural taxa in the area, such as Pinus, Tilia and Carpinus.
This chapter presents the available evidence for the impact of people on vegetation around the time of the ‘Scandinavian’ settlement of the North Atlantic islands. A common phenomenon around the time of landnám is the expansion in the pollen of Poaceae and/or Cyperaceae. These ubiquitous taxa have frequent fluctuations and declines throughout the Holocene spectra and cannot, alone, be designated as providing anthropogenic ‘footprints’. The Norse settlement of Iceland offered fresh opportunities for plants to migrate westwards with the wave of Norse colonists, resulting in the addition of a number of new species to the Icelandic flora. Reconstructions of the pre-settlement vegetation of Iceland contrast markedly with the currently open and exposed character of the landscape. A notable change to the flora of Greenland around the time of Norse settlement is the appearance and increase in Rumex acetosella.
The archaeological sites in the open‐cast mine of Schöningen, Germany, represent outstanding archives for understanding Middle Pleistocene interglacial–glacial transitions and human adaption. Aquatic microfossil and pollen assemblages from the ‘Reinsdorf sequence’, likely correlated to Marine Isotope Stage 9, document environmental changes from a thermal maximum to succeeding glacial conditions recorded in two sequences of excavation sites 12 II and 13 II. Multi‐proxy analyses enable detailed reconstruction of lake‐shore and landscape developments despite variable microfossil preservation in changing carbonate‐ and organic‐rich deposits. Rich aquatic vegetation with abundant charophytes suggests repeated phases with water depths of 0.5–2 m at site 13 II, while even greater temporary depths are deduced for 12 II DB. Mesorheophilic and mesotitanophilic ostracod species indicate stream inflows with medium–low calcium contents of >18 mg Ca L–1 originating from nearby springs. Diatoms point to meso‐eutrophic conditions and an alkaline pH of the lake water. Interglacial conditions with thermophile forests but no aquatic microfossils preserved, suggesting a dry or only temporarily flooded site, mark the beginning of the sequence. Continuous presence of aquatic organisms and overall dominance of small tychoplanktonic diatoms during a subsequent cool steppe phase provide evidence for increased water depths and unstable habitats characterized by erosion and probably prolonged periods of lake ice cover. During the succeeding boreal forest‐steppe phase, surface runoff into the productive, shallow lake decreased due to a more extensive vegetation cover. Concurrently, intensified groundwater input in contact with the nearby salt wall caused elevated salinities. Following a lake level drop, stream inflows and lake levels increased again towards the end of the Reinsdorf sequence and promoted development of a diverse fauna and flora at the lake shore; thereby maintaining an attractive living and hunting environment for early humans during a phase of generally cooler temperatures and landscape instability at the transition into a glacial period.
The settlement of Iceland is known to have had profound impacts on vegetation and landscape stability, but there remain uncertainties around the spatial variability and timing of environmental change, and the impacts of settlement on aquatic ecosystems. Here a new multiproxy palaeoenvironmental reconstruction spanning the last 3000 years is presented from Kalmanstjörn, a small lake in Mývatnssveit, northeast Iceland. Sedimentology, pollen and non‐pollen palynomorphs, and geochemical proxies, dated using tephrochronology, are used to reconstruct terrestrial vegetation, landscape stability and aquatic ecosystems. The data reveal complex environmental dynamics after settlement. At this site, substantial tree populations persisted until the late 15th century, in strong contrast to the rapid deforestation shown by almost all other records from Iceland. The eventual loss of woodland may have been caused by changes in direct human activity and the location of extensive grazing, in combination with Little Ice Age climatic cooling. The loss of woodland was accompanied by increased soil erosion. Conversely, the lake ecosystem showed an immediate response to settlement, becoming more productive for several centuries, perhaps in response to increased availability of nutrients from grazing herbivores. The late persistence of woodland in the Kalmanstjörn record adds to our understanding of the spatial variations in ecosystem responses to settlement in Iceland, while the evidence for decoupling of the aquatic and terrestrial systems suggests that palaeolimnological reconstructions focusing on aquatic ecosystem responses may be important new sources of information on the wider ecological consequences of human settlement.
Palynological and geochemical analyses provide valuable information about modern and past climatic regimes and vegetation. The impact of climate and humans on past vegetation in the semi-arid areas of northwestern Iran has received increased interest in the wake of warming temperatures in the Middle East. Palynological and down-core XRF elemental abundances from a peat core from Lake Neor enabled a reconstruction of vegetational changes of the past 7000 years over the highlands of northwestern Iran. Periods of increased arboreal pollen (AP) types and high (Artemisia + Poaceae)/Chenopodiaceae ratios along with low titanium abundances, high percentages of total organic carbon, more negative δD values, and higher carbon accumulation rates suggest a relatively wet climate. These conditions have persisted during the periods 6700-6200, 5200-4450 and 3200-2200 cal a BP. The overall low AP values, substantial rise of Chenopodiaceae, high Ti abundances and low values of palaeo-redox proxies, are all evidences of a drier climate, as has been reconstructed for the periods 6200-5200 and 4030-3150 cal a BP and the last 2200 years. An important feature of the last centuries is the increase of anthropogenic and pastoral indicator pollen types. Our results may provide basic data to predict future trends in vegetation dynamics under future climate change in western Asia.
Qikirtajuaq is a long island facing the Inuit village of Akulivik on the northeastern coast of Hudson Bay (Canada) that is rich in archaeological sites. Kangiakallak‐1 (JeGn‐2), one of the main sites on this island, is a large multicomponent site that includes Dorset and Thule Inuit winter houses. This study documents the dynamics of palaeoenvironmental conditions in the successive occupations of the Kangiakallak‐1 settlement based on plant macrofossils, pollen and non‐pollen palynomorph analyses and archaeological research. The data indicate that Dorset inhabitants constructed their dwelling at about 772 cal. a BP. The site was reused by the Thule Inuit a few decades later, starting at about 671 cal. a BP. Thus, Kangiakallak‐1 is one of the few sites, at least in Nunavik (northern Québec, Canada), that were rapidly reoccupied by the Thule Inuit after the departure of the Dorset inhabitants, which indicates a possible overlap between the two cultures in the Akulivik region. The palaeoecological data show that both Dorset and Thule inhabitants left clear footprints at the local scale in the form of several nitrophilous species that became established in and near the houses and persisted over a long period. The deposition of domestic waste (including bone fragments, skin, burnt fat and charcoal fragments) inside the subterranean dwellings fertilized the soil and led to the growth of unique nitrophilous plants. These changes transformed the houses into exceptional floristic refuges.
Purification protocols to extract pollen from lake sediments contain chemicals that alter the carbon and oxygen pollen‐isotope values according to pollen characteristics and family affiliation. Modern (raw) pollen of broad‐leaved (Alnus glutinosa, Betula pendula, Carpinus betulus, Corylus avellana, Fagus sylvatica and Quercus robur) and coniferous tree species (Picea abies and Pinus sylvestris) were treated with potassium hydroxide (KOH), hydrofluoric acid (HF), sodium hypochlorite (NaClO) and sulphuric acid (H2SO4) to test the impact on δ13Cpollen and δ18Opollen and assess the applicability in purification protocols. Pollen of broad‐leaved and coniferous trees reacted differently to chemical exposure, but response patterns are generally alike. Alterations of δ13Cpollen values vary between + 1.0‰ (B. pendula, NaClO‐treatment) and −5.0‰ (P. sylvestris, H2SO4‐treatment). The δ13Cpollen values of raw and chemically treated samples seem to be related after treatments with KOH, NaClO and HF, whereas the application of H2SO4 led to inconsistent changes among species. The impact of chemicals on δ18Opollen are more diverse and offsets range between +1.1‰ (C. avellana, NaClO‐treatment) and −17.9‰ (P. sylvestris, H2SO4‐treatment). In general, the use of isotope‐altering chemicals in purification protocols should be brought to a minimum, but the application of KOH and NaClO seems mostly unproblematic before δ13Cpollen and δ18Opollen analysis.
Aim: Temperate forests are currently facing multiple stresses due to climate change, biological invasions, habitat fragmentation and fire regime change. How these stressors interact with each other influences how, when and whether ecosystems recover, or whether they adapt or transition to a different ecological state. Because forest
recovery or collapse may take longer than a human lifetime, predicting the outcomes of different stressor combinations remains difficult. A clearer vision of future forest trajectories in a changing world may be gained by examining collapses of forests in the past. Here, we use long-term ecological data to conduct a post-mortem examination
of the decline of maritime pine forests (Pinus pinaster Ait.) on the SW Iberian Peninsula 7000–6500 years ago.
Location: Portugal and Spain.
Methods: We compared four palaeoecological records—two with pine declines and two without—using a multiproxy approach. Bioclimatic differences between the four sites were explored. Proxies for past vegetation and disturbance (fire and grazing) were compared with independent palaeoclimatic records. We performed functional traits analysis and used phase plots to examine the causes of pine decline.
Results: The pine decline represents a critical transition in SW Iberia, which lies close to maritime pine's bioclimatic limits. Prolonged drought likely killed trees and suppressed the fires that normally stimulate pine germination and pinewood recovery. Increased grazing pressure facilitated the rapid spread of resprouter shrubs. These
competed with pine trees and ultimately replaced them. Our data highlight complex interactions between climate, fire, grazing and forest resilience.
Main Conclusions: The pine decline occurred at least a century after post-fire resprouters overtook obligate seeders in the vegetation, constituting an early-warning signal of forest loss. Fire suppression, resprouter encroachment and grazing may threaten the persistence of Mediterranean forests as droughts become more frequent and extreme.
Palynomorphic studies of 65 common mellitophilous and 16 allergenic flora of Arid and Northern irrigated agroecological zones of Pakistan are carried out in this study by using field emission scanning electron microscope (FESEM). Mellitophilous pollen were extracted from honey samples of selected sites. For collection of local allergenic pollen, previously identified allergy‐causing plants were selected. Pollen morphological examination was carried out under FESEM. Diverse range of pollen shapes ranging from monad to polyad and sculpturing ranging from psilate to echinate, scabrate to reticulate, bireticulate, or echinolophate were observed. Brassicaceae, Myrtaceae, Asteraceae, Rosaceae, and Poaceae were observed to be dominant allergenic and mellitophilous families of the selected sites. Allergenic pollen and honey samples collection Melliferous pollen extraction from honey samples Allergenic and melliferous pollen preparation for field emission scanning electron microscope (FESEM) studies Taxonomic studies of allergenic and melliferous pollen and their sculpturing using FESEM Development of detailed allergenic and melliferous pollen spectrum Diverse range of the pollen shapes were observed ranging from monad to polyad Pollen sculpturing ranging from psilate to echinate, scabrate to reticulate, bireticulate or echinolophate were observed. Brassicaceae, Myrtaceae, Asteraceae, Rosaceae, and Poaceae families were observed to be dominant allergenic and mellitophilous families of arid and northern irrigated agro ecological zones of Pakistan Pollen sculpturing ranging from psilate to echinate, scabrate to reticulate, bireticulate or echinolophate were observed. Brassicaceae, Myrtaceae, Asteraceae, Rosaceae, and Poaceae families were observed to be dominant allergenic and mellitophilous families of arid and northern irrigated agro ecological zones of Pakistan
Northeastern Brazil has thousands of wetland fossiliferous deposits with megafauna and, in some cases, associated lithic artefacts. The timing of the arrival of humans in South America and the extinction of megafauna is still debated and these sites contribute both to this discussion and to the reconstruction of the Upper Pleistocene and Holocene paleoenvironment. Lagoa do Quari, 40 km south of São Raimundo Nonato, Piauí state, is a marsh deposit in the present semi-arid caatinga environment, excavated by an interdisciplinary team in 2002-2003. This paper presents the archaeological, paleontological, geological, chronological, stratigraphical and palynological results and their implications for the Quaternary of northeastern Brazil. The site has a rich megafaunal bonebed at the bottom, dominated by Eremotherium giant sloth remains with poor biodiversity, and a sandy-silty deposit at the top; two 14 C dates constrain this latter layer to 9944-9557 and 6308-6177 cal. years BP and the associated rich lithic industry of quartz and chert shows a technical continuity throughout the Holocene in the region. Palynology describes an open landscape with periodic wet phases which could explain the richness of the archaeological occurrences in Holocenic Brazilian prehistory. This research offers a model of interdisciplinary inquiry into the paleoenvironment and prehistory of lowland South America.
In southern Iberia, the surroundings of the Strait of Gibraltar are known as a crossroad for population movements, cultural exchanges, and trade from Late Prehistory to modern times. However, questions remain about the impact of this historical development on the environment. The settlement of La Silla del Papa, an important hillfort in southern Andalusia (Cádiz), was occupied during the entire Iron Age, replaced by the coastal town Baelo Claudia during Roman times, and re‐occupied during Early Medieval times. As such, La Silla del Papa and its territory represent an ideal location for long‐term studies on human‐environment interactions. Within the framework of the interdisciplinary project “Archeostraits,” geoarchaeological investigations in the surroundings of La Silla del Papa aimed at constraining ecological conditions and human‐environment interactions during the mid‐ and late Holocene and during major human occupation phases. Our results document an early mid‐Holocene marine embayment in the lower floodplain of the Río del Cachón, rapidly turning into a coastal lagoon and later into freshwater‐dominated wetlands. After approximately 2100 BP (c. 150 BC), fluvial and alluvial deposition increased, suggesting a high anthropogenic impact on the local landscape during Roman or post‐Roman times. Palynological results reveal fluctuating agricultural and pastoral activities and distinct periods of landscape opening during the Neolithic and Iron Age.
The northern Greater Khingan Range is located in northernmost Northeast China on the southern edge of the permafrost zone of the Northern Hemisphere. Isolated, sporadic and continuous permafrost belts are distributed from the southeast to the northwest in this area. Sixteen surface soil samples were collected from the three permafrost belts, and a 30‐cm‐deep soil profile was sampled from the continuous permafrost belt. A 70‐cm‐long sediment core was recovered from a small lake in the continuous permafrost belt. Measurements of mineral magnetism and analysis of total organic carbon (TOC) and total nitrogen (TN) were performed on the soil samples, while mineral magnetism measurements, pollen analysis and accelerator mass spectrometry (AMS) 14C dating were made on the lake sediment samples. The purpose was to explore whether the mineral magnetism of the soils and sediments in combination with TOC, C/N and pollen data would be indicative of recent and past permafrost alterations. Stable single domain (SSD) ferrimagnets were rarer in relative and/or absolute terms in the surficial isolated‐sporadic permafrost and the upper horizons of the soil profile, suggesting stronger gleization and thawing. The variations in TOC and C/N support these inferences. Temporal changes in mineral magnetism of the sediment core indicate varying pedogenesis and gleization and permafrost aggradations and degradations in the catchment and shifts of the permafrost belts over the past ~1000 years. The reconstructed permafrost alterations attributable to local climate changes suggested by the pollen data can be related to northern hemispheric and regional climate changes in the past ~1000 years and are helpful for predicting migrations of the permafrost belts in the future.
Southern Siberia is characterized by complex climatic and vegetation patterns, and the late‐Quaternary evolution of climate and vegetation in this vast region is still poorly understood. This study uses pollen, spores, testate amoebae and plant macrofossils to characterize environmental and climatic changes at Bezrybnoe Mire (Western Sayan Mountains, southern Central Siberia). Pollen data indicate permanent forest cover in the region during the Late Holocene and subtle variations in abundances of dominant taxa (Pinus sibirica, Abies sibirica, Larix, Pinus sylvestris and Betula pendula). Higher values of Betula and Artemisia at the beginning of the record (>2500 cal. a BP, probably c. 3300 cal. a BP) and c. 420–140 cal. a BP suggest slight expansion of birch forest and steppe. The intervening period has higher values of dark taiga taxa, suggesting a shift to higher moisture levels. Superimposed on this longer‐term variation, the testate amoeba record of mire wetness reveals 12 sub‐millennial episodes of drier conditions (with a sample resolution of c. 50–90 years). Mire plant communities reacted to the high‐frequency fluctuations in moisture but with a delayed response of c. 30–40 years. Both the short‐ and long‐term variations in moisture show general concordance with neighbouring regional records and align with observed cultural changes of the Eurasian steppe region. These variations in moisture probably relate to the degree of penetration of the moisture‐bearing Westerlies into southern Siberia.
There is a notable lack of palaeoecological records, particularly quantitative palaeoenvironmental reconstructions, for northeast Sweden. Here I use a lake sediment record from lake Flocktjärn to reconstruct Holocene terrestrial vegetation change and lake ecosystem dynamics, and to study the relationship between these components of the environment. After a period in which the vegetation around the lake is characterized by boreal forest, thermophilous arboreal taxa such as Ulmus establish in the Flocktjärn area from 6000 cal. a BP onward. Picea becomes abundant from 2930 cal. a BP onward, in line with results from other records from the region. The chironomid fauna of the lake shows high turnover before 7700 cal. a BP, after which an assemblage dominated by taxa indicative of shallow, warm and relatively nutrient rich conditions establishes. A transition to chironomid taxa that are indicative of slightly lower temperatures and lower nutrient levels occurs at 5260 cal. a BP. A chironomid‐inferred mean July air temperature record shows unreliable inferences for the record pre‐dating 7700 cal. a BP, a Holocene Thermal Maximum with temperatures around 14 °C between 7700–5260 cal. a BP, and temperatures around 12.5 °C between 5260 cal. a BP and the present. A numerical comparison between upland vegetation change and chironomid faunal dynamics for the first time shows that either vegetation change directly impacted on the chironomid fauna of the lake, or alternatively an external factor impacted on both the terrestrial and the aquatic ecosystem, resulting in concurrent changes in both parts of the ecosystem. This novel evidence of ecosystem connectivity is of vital importance to landscape management, as ongoing climate and land use change is likely to lead to increased pressure on lake ecosystems.
Bolshaya Imandra, the northern sub‐basin of Lake Imandra, was investigated by a hydro‐acoustic survey followed by sediment coring down to the acoustic basement. The sediment record was analysed by a combined physical, biogeochemical, sedimentological, granulometrical and micropalaeontological approach to reconstruct the regional climatic and environmental history. Chronological control was obtained by 14C dating, 137Cs, and Hg markers as well as pollen stratigraphy and revealed that the sediment succession offers the first continuous record spanning the Lateglacial and Holocene. Following the deglaciation prior to c. 13 200 cal. a BP, the lake's sub‐basin initially was occupied by a glacifluvial river system, before a proglacial lake with glaciolacustrine sedimentation established. Rather mild climate, a sparse vegetation cover and successive retreat of the Scandinavian Ice Sheet (SIS) from the lake catchment characterized the Bølling/Allerød interstadial, lasting until 12 710 cal. a BP. During the subsequent Younger Dryas chronozone, until 11 550 cal. a BP, climate cooling led to a decrease in vegetation cover and a re‐advance of the SIS. The SIS disappeared from the catchment at the Holocene transition, but small glaciers persisted in the mountains at the eastern lake shore. During the Early Holocene, until 8400 cal. a BP, sedimentation changed from glaciolacustrine to lacustrine and rising temperatures caused the spread of thermophilous vegetation. The Middle Holocene, until 3700 cal. a BP, comprises the regional Holocene Thermal Maximum (8000–4600 cal. a BP) with relatively stable temperatures, denser vegetation cover and absence of mountain glaciers. Reoccurrence of mountain glaciers during the Late Holocene, until 30 cal. a BP, presumably results from a slight cooling and increased humidity. Since c. 30 cal. a BP Lake Imandra has been strongly influenced by human impact, originating in industrial and mining activities. Our results are in overall agreement with vegetation and climate reconstructions in the Kola region.
The paper presents the results of a palaeoecological study of Neolithic archaeological layers from a wetland, multilayer site, Serteya II (Western Russia). It contains , domestic structures, rich organic artefacts, skeletons, and ecofacts preserved within lacustrine deposits that are extremely important on a European scale. We employed a set of specialised palaeoecological analyses and accelerator mass spectrometry radiocarbon dating to identify the principal environmental conditions which attracted Neolithic hunter-fisher-gatherer communities from 4300 to 1600 cal. BC. The distinct impact of communities using a nonproductive economy on the ecology of the palaeolake shore zone was recorded. Also, palaeolake water level changes influenced the palaeoeconomic activity of local Neolithic societies, such as gathering of plants (for the medicinal use or serving as dietary components), fishing activities, and possible funeral practices. In addition, the identified phases of high-water level changes, which were responses to climatic oscillations, were correlated with supraregional climatic events, especially ca. 6.2, 5.9, and 4.2 ka cal. BP. Thus, our results allowed for the reconstruction of environment transformations and conditions of Neolithic communities' activity, as well as for a better understanding of the relationships between local Neolithic communities' way of life and neolithisation processes in Eastern Europe.
Wood macrofossil remains of alder and willow/poplar have been recovered from a sediment sequence in the valley of the Turker Beck in the Vale of Mowbray, North Yorkshire. These remains have yielded radiocarbon dates early in the Devensian Late Glacial (14.7-14k cal a BP), equivalent to the early part of the Greenland Interstadial (GI-1e) of the GRIP ice-core record. These are the earliest dates recorded for the presence of alder in the Late Glacial in the British Isles. Associated biological remains have provided a palaeoenvironmental record for this early part of the Greenland Interstadial, generally indicative of open environments dominated by herbaceous taxa on both the wetland and dryland surfaces. However, stands of alder, birch and willow woodland were also present, and indicate the possibility that such tree species survived in cryptic refugia in Britain as elsewhere in northern Europe during the Last Glacial Maximum. The absence of alder pollen at Turker Beck, in a sequence in which its macrofossil remains are relatively abundant, lends support to the view that pollen can be a poor indicator of the presence of tree species in Late Glacial sequences in northern and western Europe.
Buried karst features result from a complex interplay between carbonate bedrock and structural geology. The enhancement of carbonate aquifers through this interplay creates hydrogeologically-complex subsurface drainage networks and highly variable surface topographies. This paper reports on the sediment fill and fossil pollen record from a large enclosed negative karst landform at Coolough, near Galway City in the west of Ireland. It was discovered during the preliminary site investigation for the proposed N6 Galway City Ring Road. Major joint sets developed in the Carboniferous (Mississippian) limestone bedrock govern the local hydrogeology and structural evidence suggests that a local fault has controlled the east-west propagation of the deep enclosed depression. Fluvial and lacustrine palaeoenvironments are interpreted from the sediments infilling the enclosed depression, within which three discrete diamicts are identified, potentially representing distinct phases of glaciation. Pollen assemblages, which reflect palaeoenvironments of open woods and grasslands, have been correlated with other deposits in Ireland and Europe and suggest a minimum date of the Early Pleistocene for the oldest of the diamicts, and thus an upper age limit on the development of the karst depression. Fluvial disturbance to the deposit is evident and is likely to be responsible for the chronological discrepancy between the Early Pleistocene and Middle Pleistocene sediments both recorded from the deposit infill. The findings of this multidisciplinary study contribute to an understanding of Quaternary landscape evolution in western Ireland.
The quality assurance and authentication of crude herbal drugs play important role in the effective therapeutic effect of herbal drug and their products. There are many reported problems in quality assurance of herbal crude drugs concerning to their correct identification. The present study was designed with the aim to document the authentication and quality assurance of the herbal crude drugs (Argyrolobium roseum and Viola stocksii) thorough light microscopy (LM) and scanning electron microscopy (SEM). The detailed foliar anatomical studies showed polygonal epidermal cells having anticlinal walls in Argyrolobium roseum while rounded epidermal cells were observed in Viola stocksii. The anomocytic stomata type was observed in Argrolobium roseum while actinocytic was noticed in Viola stocksii. The pollen of studied species appeared as tricolporate showing reticulate exine sculpturing in Argrolobium roseum while fine perforations were recorded in Viola stocksii. Furthermore, quantitative analysis of phenols, flavonoids, and antioxidant activity showed high flavonoid and phenol content in Argyrolobium roseum as compared with Viola stocksii. It was observed that Argyrolobium roseum was discriminated from the Viola stocksii based on the leaf and pollen micromorphological traits by using LM and SEM techniques. It was concluded that LM and SEM techniques were found useful for the quality assurance of botanicals and their authentication. Polygonal epidermal cells having anticlinal walls were found in Argyrolobium roseum and rounded were observed in Viola stocksii. The pollen were tricolporate showing reticulate sculpturing in Argrolobium roseum while perforations in Viola stocksii LM and SEM are found to be very useful tools for quality assurance of herbal drugs (Argyrolobium roseum and Viola stocksii)
Late Glacial coversand landscapes are important archives of environmental change during the Pleistocene–Holocene transition as well as of Final Paleolithic human adaptation to these changes. However, extensive reconstruction of these landscapes is hampered by the fact that they are often preserved best when covered with later eolian, alluvial and/or marine sediments. These paleolandscapes are generally mapped by means of manual or mechanical coring to date, which is rather expensive and labor‐intensive. This study aims to develop a more efficient methodology to map paleolandscapes buried within the coversand and below Holocene floodplain deposits, using a case study in NW Belgium. Electric cone penetration testing is established as a primary technique for mapping the paleotopography of thin organic rich layers within the coversand, in combination with core sampling for lithostratigraphic correlation and validation. Radiocarbon dating and pollen analyses are used to investigate the chronological and biostratigraphic context, respectively. The results reveal the paleotopography of three undulating organic rich stabilization surfaces within the coversand, which were formed from the GI‐1d to GI‐1a. These paleosurfaces provide valuable contexts for studying Final Paleolithic archaeology in the coversand region specifically, but the developed methodology is applicable to Paleolithic archaeology in general.
Between 2800 and 2400 cal BC pastoralists from Central Europe migrated into the eastern Baltic paving the way for the Corded Ware Culture (CWC), and a new type of economy, animal husbandry. Traditionally the CWC people were viewed as highly mobile due to the lack of substantial traces of dwellings and material culture at settlement sites; they were reliant on an economy based on animal husbandry as demonstrated by zooarchaeological and stable isotopic evidence. However, this paradigm is beginning to shift. Here, we present new AMS radiocarbon (14C) measurements, pollen and macrobotanical data from sediment samples and a portable fish screen, as well as technological, molecular and isotopic data obtained from ceramic vessels from three CWC sites in the eastern Baltic. Overall, our results indicate a de‐Neolithisation process undergone by some CWC groups, particularly in lacustrine and coastal ecotones, and a shift to hunting, gathering and fishing.
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