Journal articles on the topic 'Arboreal pollen'
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1
Bera, S. K., and H. P. Gupta. "Correlation between pollen spectra and vegetation of Chhota Shigri Glacier in Himachal Pradesh, India." Journal of Palaeosciences 38 (December 31, 1989): 404–10. http://dx.doi.org/10.54991/jop.1989.1675.
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Pollen analysis of modern surface samples and glacial deposits, collected from Chhota Shigri Glacier at different altitudes ranging between 3.750 to 5.010 m, has been carried out to understand the pollen/vegetation relationship. The study reflects the predominance of extra-regional arboreals over local non-arboreal taxa.
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Chauhan, M. S., and M. F. Quamar. "Pollen rain deposition pattern in tropical deciduous Sal (Shorea robusta Gaertn.) forest in Shahdol District, Madhya Pradesh, India." Journal of Palaeosciences 62, no. (1-2) (December 31, 2013): 47–53. http://dx.doi.org/10.54991/jop.2013.334.
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The pollen rain–vegetation relationship study, based on pollen analysis of 6 surface samples from tropical deciduous Sal (Shorea robusta Gaertn.) forest at Khanaudi, Shahdol District reveals the relatively lower frequencies of arboreal taxa in contrast to non–arboreal taxa. Among the arboreals, Shorea robusta, a dominant forest constituent, is not represented appropriately in the pollen–rain and encountered with av. 2% pollen only in the sediments. The under–representation of Shorea robusta pollen, despite being high pollen producer, could be attributed to its poor preservation in the sediments as well as low dispersal efficiency. On the other hand, the consistent presence of Madhuca indica, a common associate of Sal, and Sapotaceae with high frequencies of average 19% and 6%, respectively corresponds more or less with their frequent presence in the forest coupled with good preservation of their pollen in the sediments. However, a large number of other associates of Sal, viz. Terminalia, Lagerstroemia, Emblica officinalis, Syzygium, Holoptelea, Sterculia, etc. occurring appreciably in the forest, denote sporadic presence with av. 10% pollen only owing to their low pollen productivity, since they are entomogamous. Thus, av. 39% arboreal pollen including av. 37% trees and av. 2% shrubs, though scanty, represent the modern Sal forest in the region. The abundance of pollen of grasses, sedges, Tubuliflorae, etc. corresponds with their composition in the ground flora. The consistently moderate frequencies of Cerealia and Cheno/Am coupled with sporadic pollen of Artemisia, Cannabis sativa and Caryophyllaceae indicate the proximity of cultivated land.
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Verma, Divya. "PREVALENCE OF AIRBORNE POLLEN GRAINS AND FUNGAL SPORES IN A CITY OF THAR DESERT, INDIA." Journal of Advanced Scientific Research 13, no. 08 (September 30, 2022): 45–53. http://dx.doi.org/10.55218/jasr.202213808.
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Monitoring of bioaerosols i.e., pollen grains and fungal spores, was undertaken for two consecutive years in a city of Thar Desert- Bikaner, using Gravity Slide Method. A total of 32 different pollen taxa were identified with Annual Pollen Integral (API) of 890 pollen grains per sq. cm in the first year and 906 pollen grains per sq. cm in the second year. The pollen count of non-arboreal plants was much more than that of the arboreal plants. The most prominent annual average pollen percentage was credited to Poaceae (25.91%), followed by Chenopodiaceae/Amaranthaceae (17.57%), Papilionaceae (7.86%) and Cyperaceae (5.95%) among non-arboreal plants: and to Prosopis juliflora (14.84%) amongst arboreal taxa. Two peak seasons were observed in both the years i.e., February to April and August to October for both pollen grains as well as fungal spores. 32 types of airborne fungal spores were reported from the atmosphere of Bikaner during the study. A total number of 6717 fungal spores per sq. cm were counted in the first year and 7117 spores per sq. cm in the second year. The commonest fungal spores encountered were of the species of Cladosporium, followed by Alternaria and Curvularia with annual mean percentage of 24.95%, 23.02% and 11.53 respectively.
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Verma, Poonam, and M. R. Rao. "Modern pollen and vegetation relationship in the teak deciduous forest in Sehore District, Madhya Pradesh." Journal of Palaeosciences 62, no. (1-2) (December 31, 2013): 55–63. http://dx.doi.org/10.54991/jop.2013.336.
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Pollen analyses of 19 surface soil and mud samples in and around Kusumelli Swamp near Shahganj, Sehore District of Madhya Pradesh were carried out to understand modern pollen and vegetation relationship in the dry deciduous teak dominated forest region. The palynological assemblage demonstrates pervasiveness of non–arboreal (herbs) forms in comparison to arboreal (trees and shrubs) taxa. Maximum arboreal pollen are recorded in forest floor (average 37%) in comparison to lake floor sediments (average 33%) followed by forest vicinity mud (average 29%) and forest edge open area (average 24%). The most common constituent of modern forest floristic, i.e. teak (80–90%) is recorded by average of 1% in lake, forest and adjoining floor sediments. The other members such as Madhuca indica (average 2.1%), Syzygium sp. (average 1.6%), Terminalia sp. (average 1.4%), Butea monosperma (average 1%), Embilica officinalis (average 0.7%), Diospyros sp. and Lannea grandis (average 0.6%) are also recorded in low frequencies. This discrepancy in the pollen deposition pattern is possibly due to their low pollen production and partial preservation in sediments. Stumpy pollen frequency of Sal (average 0.4%) recovered in open area and lake floor sediments could be ascribed to its anemophilous mode of pollination and transportation through low turbulent winds and water from nearby area. However, better representation of Holoptelea (average 4.4%) and Buchanania lanza (average 3.8%) in all sediment samples can be substantiated through their huge pollen production and higher dispersal efficiency. In addition, non–arboreal representatives such as Asteraceae (Tubuliflorae and Liguliflorae), Caryophyllaceae, Malvaceae, Brassicaceae, Chenopodiaceae/Amaranthaceae and Cannabinaceae, etc. more or less reflect actual composition of the ground flora. The comparative database generated on pollen–vegetation spectra will serve a modern pollen analogue for factual appraisal of fossil pollen successions deposited during Quaternary Period in the region.
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Piotrowska-Weryszko, Krystyna, and Elżbieta Weryszko-Chmielewska. "Spatial differentiation of airborne arboreal pollen in Lublin (Poland)." Acta Agrobotanica 68, no. 4 (2015): 333–41. http://dx.doi.org/10.5586/aa.2015.035.
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The study compared the occurrence of airborne pollen of 7 arboreal taxa (<em>Corylus</em>, <em>Alnus</em>, Cupressaceae/Taxaceae, <em>Populus</em>, <em>Fraxinus</em>, <em>Betula</em> and <em>Carpinus</em>) during the period 2007–2009 from two sites in Lublin city, SE Poland. The sites differed in the character of building development and surrounding vegetation. Pollen monitoring was conducted by the volumetric method using two Hirst-type samplers. Daily and intradiurnal pollen counts were determined. For all the taxa, Spearman’s test revealed statistically significant positive correlations between daily pollen fluctuations at two sites. Nevertheless, the Mann–Whitney <em>U</em>-test showed differences for Cupressaceae/Taxaceae, <em>Fraxinus</em>, <em>Populus</em> and <em>Corylus</em> between sites. The intradiurnal pattern of pollen concentration was characterized by high variation. Cupressaceae/Taxaceae and <em>Populus</em>, clearly differed in hourly pollen concentrations at both sites. Moreover, in the case of <em>Betula</em> and <em>Alnus</em> it was shown that a part of pollen recorded in Lublin can originate from long-distance transport. High pollen concentrations can be expected at different hours of the day. The lowest average pollen concentrations at both sites were found during morning hours at 5 and 6 a.m. Based on the obtained results, it can be concluded that data from a single pollen-sampling device are not representative of some taxa in the particular districts of the city. Average data obtained from at least two pollen samplers could provide optimum results.
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Kutluk, Hatice, and Burhan Aytug. "Airborne pollen flora of a deciduous mesic forest in Turkey." Bangladesh Journal of Plant Taxonomy 17, no. 1 (June 29, 2010): 23–31. http://dx.doi.org/10.3329/bjpt.v17i1.5388.
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Airborne pollen composition of a deciduous mesic forest in northwestern Turkey is compared with the flora of the forest and a wider area. The airborne assemblage is constituted by 641.553 pollen belonging to 32 orders, 54 families and 96 genera. Of these, 380.000 (59.2%) belong to native and 257.180 (40.1%) to non-native plants. Among the native taxa arboreal pollen (AP) is represented by 55.7% and non-arboreal (NAP) by 44.3%. All of the arboreal elements of the forest are Quercus, Castanea, Carpinus, Ulmus, Alnus, Populus, Salix, Fagus, Tilia, Acer, Corylus, Prunus, Rubus, Ligustrum, Phillyrea which represented in the airborne assemblage. Incorporation of NAP to airborne composition is less than AP and they more likely provide an indication of the composition of local plant communities and hence represent vegetation of immediate vicinity. The most common NAP taxa are Poaceae, Plantaginaceae, Asteraceae, Urticaceae, Apiaceae, Cannabaceae, Polygonaceae and Cyperaceae. Pollen of climbers are less represented than AP but more than NAP taxa. Platanus orientalis (30.7%) and Pinus and Cupressus (20.2%) constitute half of the non-native flora; the rest is the pollen of exotic, alien and horticultural taxa from numerous parks and gardens in İstanbul.
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Pisaric, Michael FJ, Julian M. Szeicz, Tammy Karst, and John P. Smol. "Comparison of pollen and conifer stomates as indicators of alpine treeline in northwestern Canadian lake sediments." Canadian Journal of Botany 78, no. 9 (September 1, 2000): 1180–86. http://dx.doi.org/10.1139/b00-092.
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We compare fossil pollen and stomate assemblages in 29 lake sediment surface samples from mountainous regions in northwestern Canada to characterize the relationship between modern vegetation, and pollen and stomate deposition. Modern pollen spectra were dominated by arboreal taxa originating from lower elevation sites. Pinus pollen frequently reached 30% of the pollen sum, regardless of elevation. Alpine-tundra vegetation has lower pollen abundance, even in the alpine-tundra zone, where it dominates the sparse vegetation cover. Fossil stomates were observed in all but one site where trees currently exist in the vicinity of the lake, while no stomates were found in the sediments from alpine-tundra sites. The highest concentration of stomates occurred in lake sediments from closed-canopy forested areas. Our data suggest that different boreal forest types may be differentiated based on pollen assemblages and that the presence of stomates clearly distinguishes vegetation zones dominated by arboreal vegetation from alpine-tundra zones where trees are not present.Key words: pollen, conifer stomates, treeline, Pacific Northwest.
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Gajewski, K., A. M. Swain, and G. M. Peterson. "Late Holocene Pollen Stratigraphy in Four Northeastern United States Lakes." Géographie physique et Quaternaire 41, no. 3 (December 18, 2007): 377–86. http://dx.doi.org/10.7202/032693ar.
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ABSTRACT Four pollen diagrams from Maine, New York, and Pennsylvania provide fine resolution (40 or 80 years) records of vegetation change in northeastern United States during the past 2000 years. A long term increase in pollen accumulation rates (PAR) of Picea occurred at the three sites in Maine and New York. Around 1100 years ago, Tsuga and Fagus decreased and Quercus and Castanea increased at Ely Lake in northeastern Pennsylvania. Around 500 years ago, Tsuga and Fagus greatly decreased in Maine and northern New York, while in northeastern Pennsylvania there was an increase in Tsuga and Fagus and a decrease in Quercus and Castanea pollen. Non-arboreal PAR were negligible prior to the European settlement of the area, after which there was an abrupt increase in non-arboreal pollen types.
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Trivedi, Anjali, Anju Saxena, and Mohan Singh Chauhan. "Study on modern vegetation distribution in Sevan Tal area, Raebareli District, Uttar Pradesh." Journal of Palaeosciences 68, no. (1-2) (December 31, 2019): 139–46. http://dx.doi.org/10.54991/jop.2019.40.
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Pollen analysis of ten surface sediment samples from Sevan Tal, Raebareli District (U.P.) reveals a good assemblage of arboreals (trees & shrubs) comprising Holoptelea integrifolia, Acacia nilotica, Syzygium cumini, Madhuca indica and Shorea robusta, etc. However, plant diversity in forest groves has been observed in eastern and southern fringes but are less diversified in northern and western flanks due to arable and heathland, respectively in the area. Together with av. 4% shrubs, the trees constitute av. 23.3% arboreal pollen. Even then, in general, the reduced frequencies of the trees could be ascribed to their low pollen productivity since they portray a strong tendency of entomophily. Among the non–arboreals, Poaceae with av. 35% pollen subdues the other herbaceous elements. The substantially increased frequencies of cultural taxa, viz. Cerealia, Chenopodiaceae/ Amaranthaceae (Cheno/Am), Artemisia, Cannabis sativa and Brassicaceae, more particularly on the northern and western flanks, truly reflect the intensive agriculture practice in the region. The consistent presence of marshy taxa such as Cyperaceae coupled with Polygonum plebeium, P. serrulatum and Liliaceae suggests the intermittent wetlands in the proximity of the lake. In all, the representation of the non–arboreals corresponds closely with their factual occurrence in the ground flora, constituting the largest chunk of av. 75% pollen. The frequent record of Potamogeton together with Lemna, Typha, etc. denotes the existence of the lakes around the sampling provenance. This comparative database on pollen vis–à–vis vegetation relationship serves as modern analogue for the appropriate assessment of the pollen sequence from the sediment deposit in terms of past vegetation and climate change in the Central Ganga Plain. Moreover, the representation of the arboreals, particularly trees, in the spectra symbolizes the prevailing climatic condition in the study area.
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González-Fernández, Estefanía, Sabela Álvarez-López, Alba Piña-Rey, María Fernández-González, and Francisco Javier Rodríguez-Rajo. "Data Mining Methods to Detect Airborne Pollen of Spring Flowering Arboreal Taxa." Forests 12, no. 12 (December 18, 2021): 1801. http://dx.doi.org/10.3390/f12121801.
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Variations in the airborne pollen load are among the current and expected impacts on plant pollination driven by climate change. Due to the potential risk for pollen-allergy sufferers, this study aimed to analyze the trends of the three most abundant spring-tree pollen types, Pinus, Platanus and Quercus, and to evaluate the possible influence of meteorological conditions. An aerobiological study was performed during the 1993–2020 period in the Ourense city (NW Spain) by means of a Hirst-type volumetric sampler. Meteorological data were obtained from the ‘Ourense’ meteorological station of METEOGALICIA. We found statistically significant trends for the Total Pollen in all cases. The positive slope values indicated an increase in pollen grains over the pollen season along the studied years, ranging from an increase of 107 to 442 pollen grains. The resulting C5.0 Decision Trees and Rule-Based Models coincided with the Spearman’s correlations since both statistical analyses showed a strong and positive influence of temperature and sunlight on pollen release and dispersal, as well as a negative influence of rainfall due to washout processes. Specifically, we found that slight rainfall and moderate temperatures promote the presence of Pinus pollen in the atmosphere and a marked effect of the daily thermal amplitude on the presence of high Platanus pollen levels. The percentage of successful predictions of the C5.0 models ranged between 62.23–74.28%. The analysis of long-term datasets of pollen and meteorological information provides valuable models that can be used as an indicator of potential allergy risk in the short term by feeding the obtained models with weather prognostics.
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Bunting, M. Jane. "Pollen–vegetation relationships in non-arboreal moorland taxa." Review of Palaeobotany and Palynology 125, no. 3-4 (July 2003): 285–98. http://dx.doi.org/10.1016/s0034-6667(03)00005-8.
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Lee, Jaeyoung, Chang-Pyo Jun, Sangheon Yi, Yongmi Kim, Eunmi Lee, and Dongwook Kim. "Modern pollen–climate relationships and their application for pollen-based quantitative climate reconstruction of the mid-Holocene on the southern Korean Peninsula." Holocene 32, no. 3 (November 21, 2021): 127–36. http://dx.doi.org/10.1177/09596836211060493.
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A modern pollen dataset is a prerequisite for reconstructing quantitative paleoclimate and paleovegetation cover using fossil pollen records. Although multiple modern pollen–climate datasets have been established covering a wide range of climate conditions, such datasets are exceedingly rare for the Korean Peninsula (KP). In this study, we acquired a modern pollen dataset from 198 surface soil samples collected on 37 mountains on the southern KP. Redundancy analysis (RDA) and variation partitioning results identified mean annual temperature (Tann) as the most important climate variable shaping pollen assemblages on the southern KP. Using the pollen–climate relationships inferred from the RDA, we applied the Huisman–Olff–Fresco model and determined that arboreal pollen taxa responded sensitively to the climatic gradient, whereas non-arboreal pollen taxa did not. We applied weighted averaging–partial least squares (WA-PLS) and the modern analog technique (MAT) to the pollen dataset, and a comparison of the results showed that MAT performed better than WA-PLS. A transfer function was applied to fossil pollen records from the areas covered by our dataset; the results confirmed that annual precipitation (Pann) and Tann were modulated by different mechanisms, with Pann strongly affected by El Niño–Southern Oscillation-driven typhoons during the Holocene, whereas Tann was mainly influenced by the Tsushima Warm Current from 7500 to 5100 cal yr BP depending on Kuroshio Current inflow intensity, and subsequently followed by the East Asian winter monsoon during 5100–3400 cal yr BP.
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Gillson, L., and K. I. Duffin. "Thresholds of potential concern as benchmarks in the management of African savannahs." Philosophical Transactions of the Royal Society B: Biological Sciences 362, no. 1478 (January 5, 2007): 309–19. http://dx.doi.org/10.1098/rstb.2006.1988.
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In the Kruger National Park (KNP), South Africa, ecosystem managers use a series of monitoring endpoints, known as thresholds of potential concern (TPCs), to define the upper and the lower levels of accepted variation in ecosystems. For woody vegetation, the current TPC suggests that woody cover should not drop by more than 80% of its ‘highest ever’ value. In this paper, we explore the utility of palaeoecological data in informing TPCs. We use calibrated fossil pollen data to explore variability in vegetation at two sites over the past 5000 years, to provide a long-term record of changes in woody vegetation cover and a context for interpreting more recent vegetation change. The fossil pollen data are calibrated using studies of modern pollen and vegetation from KNP; arboreal pollen percentage was simulated using pollen–landscape modelling software for savannah landscapes of varying woody vegetation cover, and the relationship between vegetation and pollen data was quantified using nonlinear regression. This quadratic equation was then applied to fossil pollen data in order to estimate woody vegetation cover from arboreal pollen percentages. Our results suggest that the TPCs have not been exceeded during the period represented in the pollen record, because estimated woody vegetation cover has remained above 20% of its highest ever value. By comparing the fossil pollen data with TPCs, our study demonstrates how palaeoecological data can be presented in a form that is directly relevant to management objectives.
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Qinghai, Xu, Yang Xiaolan, Wu Chen, Meng Lingyao, and Wang Zihui. "Alluvial Pollen on the North China Plain." Quaternary Research 46, no. 3 (November 1996): 270–80. http://dx.doi.org/10.1006/qres.1996.0066.
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Mordern alluvial pollen varies with geomorphic setting and depositional facies in sediments of the Yellow, Hutuo, and Luan rivers and in Baiyangdian and Hengshuihu lakes. Most of the arboreal pollen is derived from the mountains, whereas most of the nonarboreal pollen is derived from the plain itself. Alluvium dominated by Pinus pollen and Selaginella spores was deposited during a flood. Hydrodynamic sorting of alluvial pollen exists in the sediments of floodplain, central bar, natural levees, and point bar. In reconstructing the ancient vegetation and past climate based on pollen in alluvium, it is important to consider sedimentary facies and geomorphologic setting.
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Basumatary, Sadhan Kumar. "Studies on pollen deposition pattern in relation to modern vegetation of flood prone region in Assam, India." Journal of Palaeosciences 66, no. (1-2) (December 31, 2017): 191–99. http://dx.doi.org/10.54991/jop.2017.283.
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This paper presents a palynological dataset on Pashumara Wetland and Ranga Reserve Forest to differentiate flooded and non–flooded area in relation to existing vegetation in Assam. Study reveals that the palynoassemblage in Pashumara Wetland is an admixture of arboreal local and extra–local taxa and not fully matches with present vegetation. The various pollen distributions were observed in continuation to study sites and confirmed that pollen deposition pattern in wetland depends on parent plant growth, flood activity and surrounding vegetation. Presence of broken pollen is indicative of long distance transportation under a fluvial environment. The palynoassemblage of Ranga Reserve Forest located in non–flooded area to display modern pollen and vegetation relationship and identification of local arboreal taxa in the region. The main forest elements include Syzigium, Lagerstroemia and Emblica in the palynoassemblage are suggestive of presence of tropical deciduous forest under warm and humid climate. Pollen clumps in the palynoassemblage signifies their local origin and entomophily. This generated palynodata could be precisely utilized to distinguish flooded and non–flooded area and to interpret palaeovegetation and past climate changes in relation to palaeoflood episodes by the analysis of wetland core from the region and to correlate other tropical flood prone region of the globe.
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Puspitasari, Retno, Sri Widodo Agung Suedy, and Sri Haryanti. "Plant diversity based on pollen and spores morphology from sediment lake of Kedung Ombo Purwodadi." NICHE Journal of Tropical Biology 1, no. 2 (November 29, 2018): 35. http://dx.doi.org/10.14710/niche.1.2.35-41.
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Kedung Ombo Lake was an artificial lake that has formed since 26 years ago. Environmental has changed from the terrestrial environment into the aquatic environment, because of that the diversity of flora around the Lake Kedung Ombo was changed. The diversity of flora can be learned through the morphology of pollen and spores. Aimed of this study was to determine the diversity of plants based on the morphology pollen and spores that found in the Lake Kedung Ombo sediment. Sampling took by coring clay soil sediment in depth of 1 m, located near the outlet of Lake Kedung Ombo. Data were analyzed by making the morphology of pollen and spores description. The result showed that morphology of pollen and spores are found in the Lake Kedung Ombo sediment has a variety of shapes and sizes. The plant's diversity obtained are 25 taxa plants that were categorized into 3 taxa of arboreal pollen (AP), 9 taxa of non-arboreal pollen (NAP) and 13 taxa of spores. The dominance of taxa NAP is Celtis sp. (45,12%), this suggested that shrubs or not plant trees were more developed in Lake Kedung Ombo environment. The study concluded that the value of diversity index categorized as low and the value of similarity index categorized as high, it means that plant diversity was quite similar and there is no significant changes of diversity with their presence were quite stable.
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Aucour, Anne-Marie, Claude Hillaire-Marcel, and Raymonde Bonnefille. "Late Quaternary Biomass Changes from 13C Measurements in a Highland Peatbog from Equatorial Africa (Burundi)." Quaternary Research 41, no. 2 (March 1994): 225–33. http://dx.doi.org/10.1006/qres.1994.1024.
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AbstractStable carbon isotope ratios of total organic matter were measured in two cores collected from the Kashiru peatbog in Burundi, Equatorial Africa. The record, which spans at least the last 40,000 yr, documents the C3-C4 biomass balance in the organic sediment. Among the major modern peat formers, most plants are C3 species and are characterized by δ13C values of -25.5 ± 2.3% (vs PDB). The C4 plants, which are characterized by higher δ13C values (-11.3 ± 0.7%) belong to the Gramineae (Miscanthidium sp.) and Cyperaceae families (Cyperus latifolius, C. papyrus, Pycreus nigricans). In the fossil record, δ13C values of total organic matter vary between -28 and -15% in response to the relative fluxes of C3 and C4 plants. Before 30,000 yr B.P., low δ13C values (-23.5 ± 1.1%) match high arboreal pollen contents. From 30,000 to 15,000 yr B.P., higher δ13C values (-17.6 ± 1.1%) correspond to a significant increase in percentages of grass pollen. During this episode, a short and sharp shift toward lighter carbon isotopic compositions at 21,000 yr B.P. is synchronous with higher input of arboreal pollen. From 15,000 to 12,000 yr B.P., the 13C content decreases (δ13C = -22.9 ± 1.4%). This shift, which cannot be explained by an increase in the arboreal vegetation, could be explained by the spreading of C3 Gramineae or C3 Cyperaceae. The interval from 12,000 to 7000 yr B.P. is poorly documented in these cores due to much lower organic matter accumulation. Low δ13C values (δ13C = -25.2 ± 1.3%) are observed from 7000 to 5000 yr B.P., when the pollen data show development of C3 mountain forest. The Late Holocene is characterized by a mixed C3-C4 organic matter accumulation (δ13C = -20.9 ± 1.6%). This study depicts a change in the dominant photosynthetic pathway among the herbaceous components, notably at the glacial-interglacial transition, when C3 plants were favored by increased water supply and/or higher atmospheric CO2 concentration.
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Masi, Alessia, Alexander Francke, Caterina Pepe, Matthias Thienemann, Bernd Wagner, and Laura Sadori. "Vegetation history and paleoclimate at Lake Dojran (FYROM/Greece) during the Late Glacial and Holocene." Climate of the Past 14, no. 3 (March 13, 2018): 351–67. http://dx.doi.org/10.5194/cp-14-351-2018.
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Abstract. A new high-resolution pollen and NPP (non-pollen palynomorph) analysis has been performed on the sediments of Lake Dojran, a transboundary lake located at the border between Greece and the former Yugoslav Republic of Macedonia (FYROM). The sequence covers the last 12 500 years and provides information on the vegetational dynamics of the Late Glacial and Holocene for the southern Balkans. Robust age model, sedimentological diatom, and biomarker analyses published previously have been the base for a multi-perspective interpretation of the new palynological data. Pollen analysis revealed that the Late Glacial is characterized by steppic taxa with prevailing Amaranthaceae, Artemisia and Poaceae. The arboreal vegetation starts to rise after 11 500 yr BP, taking a couple of millennia to be definitively attested. Holocene vegetation is characterized by the dominance of mesophilous plants. The Quercus robur type and Pinus are the most abundant taxa, followed by the Quercus cerris type, the Quercus ilex type and Ostrya–Carpinus orientalis. The first attestation of human presence can be presumed at 5000 yr BP from the contemporary presence of cereals, Juglans and Rumex. A drop in both pollen concentration and influx together with a δ18Ocarb shift indicates increasing aridity and precedes clear and continuous human signs since 4000 yr BP. Also, a correlation between Pediastrum boryanum and fecal stanol suggests that the increase in nutrients in the water is related to human presence and pasture. An undoubted expansion of human-related plants occurs since 2600 yr BP when cereals, arboreal cultivated and other synanthropic non-cultivated taxa are found. A strong reduction in arboreal vegetation occurred at 2000 yr BP, when the Roman Empire impacted a landscape undergoing climate dryness in the whole Mediterranean area. In recent centuries the human impact still remains high but spots of natural vegetation are preserved. The Lake Dojran multi-proxy analysis including pollen data provides clear evidence of the importance of this approach in paleoenvironmental reconstruction. Cross-interpretation of several proxies allows us to comprehend past vegetation dynamics and human impact in the southern Balkans.
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Rodríguez-Rajo, F. Javier, Mª Victoria Jato, and Mª Carmen Seijo. "El polen de Eucalyptus y su incidencia en la atmósfera de Vigo (N.O. España)." Acta Botanica Malacitana 26 (December 1, 2001): 99–110. http://dx.doi.org/10.24310/abm.v26i0.7403.
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RESUMEN. El polen de Eucalyptus y su incidencia en la atmósfera de Vigo (N.O. España). Eucalyptus globulus Labill. es la especie arbórea de la familia Myrtaceae, más frecuente en los alrededores de la ciudad de Vigo formando abundantes y densas masas forestales. Aunque su polen se considera moderadamente alergénico, en áreas en las que, como consecuencia de repoblación forestal ocupa extensiones importantes, puede llegar a causar problemas alérgicos.Entre los años 1995 y 2000 se ha realizado el estudio aerobiológico en la ciudad de Vigo mediante un captador LANZONI VPPS 2000 situado en la margen derecha de la ría de Vigo (42°14'15"N, 8°43'30"W). La cantidad de granos de polen anual de Myrtaceae varía ampliamente, alternándose años de concentraciones bajas con otros de valores elevados que representan entre un I y un 3% del polen total anual. El valor más elevado se detectó en 1997 con 1.147 granos de polen. Se encuentra en la atmósfera de Vigo durante todo el año, aunque las concentraciones más importantes se producen generalmente durante los meses de marzo y abril. Asimismo, a lo largo del día los máximos de concentración tienen lugar entre las 15 y las 17 horas. Finalmente se ha realizado un análisis estadístico para poner de manifiesto la posible correlación existente entre las concentraciones de polen y los principales parámetros meteorológicos. El viento procedente del N-NE fue el parámetro con el que se obtuvo correlación positiva y significativa de forma constante, mientras que esta fue negativa con la humedad relativa.Palabras clave. Meteorología, Myrtaceae, Polen, Eucalyptus, Vigo.ABSTRACT. The Eucalyptus pollea and its incidence in the atmosphere of Vigo (N. W. Spain). Eucalyptus globulus Labill. is the most frequent arboreal species of the Myrtaceac family in the surroundings of the city of Vigo, and it constitues abundant and dense forestal masses. Although its pollen can be considered as a moderated allergen, in areas in which Eucalyptus was used in extended reafforestations, it can cause allergenic problems.From 1995 to 2000 a Hirst-type volumetric sampler (Hirst, 1952), LANZONI VPPS 2000 placed in the left bank of the Vigo estuary (42°14'15"N, 8°43'30"W) was used for collecting airborne pollen. From year to year important oscillations in the annual total pollen was observed, alternating years of high concentrations with other of lower values. Eucalyptus pollen counts represent a percentage that vary between I% to 3% of the total pollen, the high quantity being collected in 1997 with 1,147 pollen grains. The Myrtaceae pollen appears in the atmosphere of Vigo all over the year, although the more important concentrations are registered during March and April. Moreover, maximum daily concentrations occur between 17.00 and 18.00 hours. Finally, a statistical analysis has been carried out in order to search for the possible correlations between pollen concentration and the main meteorological parameters. The N-NE wind and relative humidity were the parameters that show the highest correlation coefficients, positive and negative respectively.Key words. Meteorology, Myrtaceae, Pollen, Eucalyptus, Vigo.
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Cordova, Carlos E., and William C. Johnson. "An 18 ka to present pollen- and phytolith-based vegetation reconstruction from Hall's Cave, south-central Texas, USA." Quaternary Research 92, no. 2 (May 7, 2019): 497–518. http://dx.doi.org/10.1017/qua.2019.17.
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AbstractPollen, spores, phytoliths, and microscopic charcoal from a sedimentary column in Hall's Cave, south-central Texas, provide information for local and regional vegetation change during the last deglaciation and the Holocene in the context of broader regional and global climatic changes. The combination of paleoenvironmental proxy data from the cave indicates that between about 18,000 and 16,500 cal yr BP the cave area was dominated by an open plant community consisting of herbaceous vegetation, dominated by C3 grasses, and scattered trees, primarily Quercus and Pinus species. After about 16,500 cal yr BP, the arboreal component fluctuated, attaining a peak between 14,000 and 13,000 cal yr BP with relatively equal proportions of C3 and C4 grasses, including a sizable proportion of Panicoideae grasses. The Younger Dryas is marked by a conspicuous decrease in arboreal pollen with an apparent increase of C4 grasses toward its termination. Early Holocene recovery of arboreal vegetation is followed by a drying trend marked by the increasing dominance of C4 drought-tolerant Chloridoideae grasses. Increasing human use of the cave in middle to late Holocene times creates noise in the climatic significance of pollen, phytolith, and other proxies, a factor to consider when interpreting paleoenvironmental proxies in other cave sedimentary records.
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Müller, Ulrich C., Jörg Pross, and Erhard Bibus. "Vegetation response to rapid climate change in Central Europe during the past 140,000 yr based on evidence from the Füramoos pollen record." Quaternary Research 59, no. 2 (March 2003): 235–45. http://dx.doi.org/10.1016/s0033-5894(03)00005-x.
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AbstractThe response of Central European vegetation to rapid climate change during the late Quaternary period (Eemian to Holocene) is assessed by data from the new pollen record of Füramoos, southwestern Germany. This record represents the longest late Quaternary pollen record north of the Alps as currently known. Its high degree of completeness allows detailed correlations with Greenland ice cores and sea–surface temperature records from the North Atlantic. Our data show that if climate deteriorations were not long or severe enough to extirpate refugia of arboreal taxa north of the Alps such as during marine oxygen isotope stage (MIS) 5 (i.e., Würm Stadial A, Stadial B, and Stadial C), reforestation with the onset of warmer conditions in Central Europe occurred on a centennial scale. If arboreal taxa became completely extinct north of the Alps such as during MIS 4 (i.e., Würm Stadial D), several thousand years were necessary for the reimmigration from refugia situated in regions south of the Alps. Thus, Dansgaard–Oeschger interstades (DOIS) 24 to 20 and 15 to 11 are expressed in Central European pollen records, whereas DOIS 19 to 16 are not recorded due to migration lags.
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Mighall, T. M., and F. M. Chambers. "Early Ironworking and its Impact on the Environment: Palaeoecological Evidence from Bryn y Castell Hillfort, Snowdonia, North Wales." Proceedings of the Prehistoric Society 63 (1997): 199–219. http://dx.doi.org/10.1017/s0079497x00002437.
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The environmental impact of the Late Iron Age and Romano-British ironworking hillfort of Bryn y Castell in upland southern Snowdonia was investigated by multiple profile pollen and charcoal analysis of nearby valley mire and blanket peat deposits. Pollen data, collected from five radiocarbon dated profiles within a 1.5 km radius of the hillfort, indicate that ironworking activities apparently had only localised impact on the environment. Small-scale declines in certain arboreal taxa can be correlated with occupancy of the site. Betula and Alnus appear to be most affected, with minor loss of Corylus and Quercus. The pattern of arboreal taxa and charcoal values during the ironworking period is considered in the context of evidence for deliberate woodland management, the scale and duration of ironworking, and alternative forms of human disturbance. Overall, the results of the pollen analysis suggest that woodland recovered to its pre-ironworking level except in the immediate vicinity of the hillfort. Integration of the archaeological and palaeoecological data allowed understanding of the resource-based aspects of this prehistoric industrial site and the results have wider implications for the field of experimental industrial archaeology.
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Villagrán, Carolina, and Juan Varela. "Palynological Evidence for Increased Aridity on the Central Chilean Coast during the Holocene." Quaternary Research 34, no. 2 (September 1990): 198–207. http://dx.doi.org/10.1016/0033-5894(90)90031-f.
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AbstractThe late Quaternary vegetation of the semiarid coast of central Chile is inferred from the palynological analysis of profiles from Quereo (31°55′S) and Quintero (32°47′S). Prior to 11,400 yr B.P., wet conditions are suggested by the abundance of pollen indicators of swamp and aquatic taxa, such as Cyperaceae and Myriophyllum, and by the presence of traces of arboreal pollen. Since ca. 10,000 yr B.P., a trend toward increasingly drier conditions is implied by the almost complete absence of arboreal and aquatic taxa, and a general decrease in the diversity of the semiarid shrubland indicators. From 3000 yr B.P. onward, the pollen records show the reappearance of swamp and aquatic taxa, presumably associated with wetter conditions, which led to recolonization by forest taxa at 1720 yr B.P. in Quintero. The drier climate detected along the semiarid coast of central Chile during most of the Holocene extended inland to the Andean foot-hills, within the present mediterranean-type climate zone of Chile, and also affected the distribution of the winter-deciduous Nothofagus forests and the northern boundary of the temperate rain forests.
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Basumatary, S. K., Swati Tripathi, and S. K. Bera. "Early Holocene pollen record of vegetation and climate history in response to the monsoonal activity in East Garo Hills, Meghalaya, India." Journal of Palaeosciences 69 (September 10, 2021): 51–61. http://dx.doi.org/10.54991/jop.2020.30.
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This study presents a palynological analysis in 2.0 m deep sedimentary soil profile procured from Rongre Swamp of East Garo Hills to document changes in vegetation and climate in response to the monsoonal activity since 10,640 cal. BP. Four palaeovegetation and climate zones were recorded based on the frequencies of major pollen taxa in the region. The first phase was around 10,640–7,540 cal. BP broadly shows the existence of tropical forest in the region under the onset of warm and humid climatic condition. Subsequently, between 7,540–5,490 cal. BP, the forest got enriched with increased values of tropical mixed deciduous and evergreen elements. The vegetation scenario as marked by both deciduous and evergreen elements in increased values support the warm and humid climate in response to the relatively high monsoonal activity. Accordingly, in the third phase between 5,490–1,120 cal. BP, the values of major arboreal pollen taxa, Shorea, Mesua, Elaeocarpus and Duabanga have declined as compared to the preceding phase in relation to the relatively less warm and humid climate than the preceding phase in the region. In the last phase around 1,120 cal. BP to present, the forest got deteriorated as evidenced by the decreased values of arboreal pollen taxa. This phase clearly depicts the high anthropogenic activity as evidenced by the abundance of cultural pollen like cereal and Brassica.
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Balakauskas, Lauras, Justina Gaižutytė, Vaidotas Valskys, and Giedrė Vaikutienė. "Analysis of pollen across the surface sediments of Lake Imbradas, Lithuania." Quaternary Research 106 (September 30, 2021): 113–28. http://dx.doi.org/10.1017/qua.2021.51.
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AbstractIn conventional pollen analysis, usually one sediment core per basin is analyzed to reconstruct past environmental conditions. This approach does not consider spatial heterogeneity of pollen assemblages, and assumes that one analyzed location is representative of the whole basin. To improve the spatial resolution of fossil pollen studies, further knowledge of the factors influencing variations in pollen assemblages throughout a basin is needed. We examined the spatial heterogeneity of pollen assemblages from 45 lacustrine surface samples from a lake with relatively simple hydrology and compared this dense network of surface pollen samples with the Lithuanian State Forest Service arboreal vegetation database. Calculations of pollen productivity at different locations across the lake revealed variations in the behavior of a pollen-vegetation relationship model in different parts of the basin. Our findings suggest that the model underestimated pollen contributions from the lakeshore vegetation. We demonstrate that detailed investigations of surface pollen as a step prior to fossil pollen investigations can provide useful insights, including understanding the influence of sedimentation rate on modelling results and spatial variations in pollen composition, thus providing guidance for site selection for fossil pollen studies.
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Weinstein-Evron, Mina. "Palynology of Pleistocene Travertines from the Arava Valley, Israel." Quaternary Research 27, no. 1 (January 1987): 82–88. http://dx.doi.org/10.1016/0033-5894(87)90051-2.
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AbstractPollen samples from the Arava travertines, dated to oxygen isotope stages 5 and 7, show relatively high arboreal pollen levels. These spectra are probably a result of an expansion of the Mediterranean maquis in Transjordan, which indicates periods of wetter climatic conditions. These periods probably represent humid fluctuations within stages 5 and 7.
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Gupta, H. P., and Chhaya Sharma. "Vegitational history and palaeoenvironment of Hirpur Locality-I, Lower Karewa, Kashmir." Journal of Palaeosciences 37, no. (1-3) (December 31, 1988): 155–58. http://dx.doi.org/10.54991/jop.1988.1612.
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The present palynostratigraphical studies carried out on the exposed sediments of Hirpur Locality-I, lying under the earlier worked out Hirpur Locality-III, has revealed continued dominance of arboreal elements in the sequence depicting comparative preponderance of spruce and oak, although showing abrupt change in their values. The palynodata thus obtained has been interpreted to reconstruct the palaeovegetation pattern and to deduce the possible climatic fluctuation witnessed during the course of sedimentation of the 40 m thick lithocolumn. The pollen diagram has been divided into four pollen assemblage zones.
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Jiang, Qinhua, and Dolores R. Piperno. "Environmental and Archaeological Implications of a Late Quaternary Palynological Sequence, Poyang Lake, Southern China." Quaternary Research 52, no. 2 (September 1999): 250–58. http://dx.doi.org/10.1006/qres.1999.2070.
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Paleoecological data from Poyang Lake, southern China, indicate that significant natural and human-induced vegetational changes have occurred during the Late Quaternary in the Middle Yangtze River valley, the likely location of rice (Oryza sativa L.) domestication. During the late Pleistocene (from ca. 12,830 to ca. 10,500 yr B.P.), the climate was cooler and drier than today's. The subtropical, mixed deciduous–evergreen broad-leaved forest which constitutes the modern, potential vegetation was reduced and herbaceous vegetative cover expanded. A hiatus in sedimentation occurred in Poyang Lake, beginning sometime after ca. 10,500 yr B.P. and lasting until the middle Holocene (ca. 4000 yr B.P.). At ca. 4000 yr B.P., the regional vegetation was a diverse, broad-leaved forest dominated by many of the same arboreal elements (e.g., Quercus, Castanopsis, Liquidambar) that grow in the area today. A significant reduction of arboreal pollen and an increase of herbaceous pollen at ca. 2000 yr B.P. probably reflect human influence on the vegetation and the expansion of intensive rice agriculture into the dryland forests near the river valleys.
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Ritchie, J. C., K. A. Hadden, and K. Gajewski. "Modern pollen spectra from lakes in arctic western Canada." Canadian Journal of Botany 65, no. 8 (August 1, 1987): 1605–13. http://dx.doi.org/10.1139/b87-220.
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Fifty-four samples of modern sediment from Banks Island and the Melville–Horton region of the Northwest Territories illustrate the major features of pollen deposition from the high to low arctic. Modern pollen deposition in the high arctic of Banks Island is characterized by up to 14% windblown tree pollen. Indicator taxa of the high and mid arctic include Oxyria (<5–23%), Saxifragaceae, Saxifraga oppositifolia, and Cruciferae (all up to 8%) and Dryas (up to 3%). Arboreal pollen increases to 60% in low-arctic and subarctic samples. Pollen concentration decreases from between 3 500 and 20 000 in the low arctic to less than 5 000 grains/cm3 in the high and mid arctic. Pollen spectra from the Late Glacial of northwestern Canada differ from those of the modern high and mid arctic not only by the absence of trees and shrubs but also in the relative proportions of Artemisia and of such indicator taxa as Oxyria and Saxifragaceae.
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Kailas, Jangam Ganga, Mudavath Chennakesavulu Naik, Madiga Bheemalingappa, Hari Ramakrishna, and Boyina Ravi Prasad Rao. "Arboreal diversity of the Andaman Islands, India, based on pollen analysis." Palynology 41, no. 3 (September 13, 2016): 370–88. http://dx.doi.org/10.1080/01916122.2016.1209592.
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Harris, W. V. "The German Landscape and Julio-Claudian Imperialism." Klio 103, no. 2 (November 9, 2021): 658–74. http://dx.doi.org/10.1515/klio-2021-0001.
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Summary New scientific work on the ancient landscapes of Germany and Britain makes it very likely that the Roman decision to abandon attempts to conquer Germany as far as the Elbe, most clearly expressed by Tiberius in 16 AD, was strongly influenced by perceptions of the heavily wooded landscape of that region. There were other reasons too: the concern of emperors to hinder potential rivals; the sheer difficulty of advancing to the Elbe; and the increasing concern of the emperor and his advisers for the fiscal effects of this and other potential conquests. But what is new is that the evidence of arboreal and non-arboreal pollen shows that Germany was a less attractive target than agrarian England.
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Miao, Y. F., X. M. Fang, F. L. Wu, M. T. Cai, C. H. Song, Q. Q. Meng, and L. Xu. "Late Cenozoic continuous aridification in the western Qaidam Basin: evidence from sporopollen records." Climate of the Past 9, no. 4 (August 9, 2013): 1863–77. http://dx.doi.org/10.5194/cp-9-1863-2013.
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Abstract. Cenozoic climate changes in inner Asia provide a basis for understanding linkages between global cooling, the Tibetan Plateau uplift, and possibly the development of the East Asian monsoon. Based on a compilation of palynological results from the western Qaidam Basin, this study reconstructed a 15-million-year (Ma) record of changing vegetation and paleoclimates spanning the middle Miocene to present (comprising two series: ~ 18–5 Ma and ~ 3.1–0 Ma, respectively). The thermophilic percentages were highest between 18 and 14 Ma, and decreased after 14 Ma, closely corresponding to the Middle Miocene Climatic Optimum (MMCO) between 18 and 14 Ma and the following global climatic cooling between 14 and 5 Ma. At the same time, decreases in the xerophytic and coniferous taxa percentages, and the increasing logarithmic ratio of non-arboreal pollen to arboreal pollen (ln (NAP/AP)), reveal the continuous aridification across both the basin and surrounding mountains. Between ~ 3.1 and 0 Ma, the percentages of the thermophilic, xerophytic and coniferous pollen as well as the ln (NAP/AP) imply further cooling and drying in this region since 3.1 Ma. We argue that these vegetation and climate patterns during the late Cenozoic western Qaidam Basin are primarily a result of the global cooling, with the Tibetan Plateau uplift and East Asian summer monsoon having contributions of lesser importance.
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Selby, Katherine A., Jane Wheeler, and Sally Derrett. "Disentangling Holocene Climate Change and Human Impact from Palaeoenvironmental Records from the Scottish West Coast." Quaternary 6, no. 1 (January 3, 2023): 2. http://dx.doi.org/10.3390/quat6010002.
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Phases of rapid climate change throughout the early to mid Holocene coincide with regional human population expansion in Scotland and North-West Europe. Palaeoenvironmental signals of climate and anthropogenically driven vegetation changes can therefore be difficult to separate. To identify whether it is possible to distinguish potential signatures of anthropogenic clearance and agricultural activities from climatic drivers of landscape change in the early to mid Holocene in the region, two topographically contrasting sites on the Isle of Skye and the Isle of Bute were investigated. A multiproxy approach including pollen, spore, microcharcoal, loss on ignition and particle size analyses was adopted to investigate changes in vegetation and climate. There are subtle indications that the 8200 cal BP climate event had an effect on the vegetation composition at both sites. Signals of anthropogenic woodland clearance are apparent early in the sequence at Peat Hill (Bute), indicated by a peak in Poaceae (grass) cereal-type (7–14%) at 8592–8793 cal BP, alongside a decrease in arboreal pollen, which could not be associated with a regional episode of climate change. Early to mid Holocene vegetation changes at Lyndale House (Skye) occur alongside regional changes in precipitation and sea level and therefore cannot be readily separated. Continuous declines in arboreal pollen from ca. 5000 cal BP at Lyndale House indicates the onset of widespread clearance on Skye via felling and sustained grazing pressures.
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Sharma, Choudhurimayum Pankaj, Suman Lata Rawat, Pradeep Srivastava, Narendra K. Meena, Rajesh Agnihotri, Anil Kumar, Poonam Chahal, SKS Gahlaud, and UK Shukla. "High-resolution climatic (monsoonal) variability reconstructed from a continuous ~2700-year sediment record from Northwest Himalaya (Ladakh)." Holocene 30, no. 3 (November 18, 2019): 441–57. http://dx.doi.org/10.1177/0959683619887426.
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A chronologically well-constrained sedimentary archive from Upshi (Ladakh) was studied using a multi-proxy approach namely palynology, environmental magnetism, total organic carbon (TOC), total nitrogen (TN), stable isotopes of carbon and nitrogen providing a continuous vegetation, and paleoenvironmental history spanning the last ~2700 years with a temporal resolution of ~43 years. Pollen assemblage shows non-arboreal pollen (NAP) and non-pollen palynomorph (NPP) were dominant around the Upshi from ~2646 to 2431 cal. yr BP, indicating warmer conditions. Arboreal pollen (AP) and NAP gradually increased from 2431 to 1860 cal. yr BP in the study area, under warm and wet conditions, corresponding to the Roman Warm Period (RWP). This phase also witnessed enhanced sediment δ15N and χlf values. From ~1860 to ~1154 cal. yr BP increased Chenopodiaceae/Amaranthaceae and substantial spread of NPP suggest decreased temperature and prevalence of cold-dry climate. This period also records declining trends of χlf, δ15N, δ13Corg, TOC, and TN contents. From ~1154 to 293 cal. yr BP, the vegetation type reversed to mixed conifer and broad-leaved forest with significant increase in herbaceous taxa, rising δ15N, δ13Corg, TOC, and TN suggesting warm and wet conditions in the study area. This period broadly corresponds to the ‘Medieval Warm Period’ (MWP). Among all the proxies employed, depth profiles of TOC and TN (wt%) appear to respond best against external climate forcing showing remarkable correlation(s) with residual Δ14C in atmosphere, indicating dominance of intrinsic solar variability on regional climate/environment. The reconstructed recorded is well connected with established historical events and cultural activities of the Eurasian region.
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van Tets, I. G. "Can Flower-Feeding Marsupials Meet Their Nitrogen Requirements on Pollen in The Field?" Australian Mammalogy 20, no. 3 (1998): 383. http://dx.doi.org/10.1071/am98383.
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Two arboreal marsupials, the eastern pygmy possum (Cercartetus nanus) and the sugar glider (Petaurus breviceps) have exceptionally low maintenance nitrogen requirements on pollen diets. This study compares their nitrogen requirements with the density of Banksia pollen that is available in the Barren Grounds Nature Reserve, New South Wales, a site where both species are known to forage on Banksia inflorescences. The pollen density was sufficiently high that both species were capable of meeting their maintenance nitrogen requirements on pollen whenever Banksia spp. were in flower. C. nanus required a smaller proportion of its home range than P. breviceps to do so and pollen was likely to be of much greater nutritional significance to both species in winter than in summer. This corresponds closely with the results of field studies comparing the diets of these mammals at different times of the year. Pollen is an important source of nitrogen for flower-feeding marsupials but its importance will vary between species depending on the marsupial's requirements, its body size and on the quantity of pollen that is available.
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Vance, Robert E. "Aspects of the Postglacial Climate of Alberta: Calibration of the Pollen Record." Géographie physique et Quaternaire 40, no. 2 (December 4, 2007): 153–60. http://dx.doi.org/10.7202/032635ar.
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ABSTRACT This reconstruction of the postglacial climate of Alberta is based on a review of pollen studies within the province and the application of calibration equations to a pollen record from central Alberta. Regional palynological studies indicate that the late glacial vegetation, dominated by non-arboreal taxa and, on occasion, Populus, was replaced by a Picea dominated assemblage between 12,000 and 10,000 BP. In central Alberta, increased herbaceous pollen representation suggests that grassland was established north of its current position in early to middle Holocene time. By 3500 BP, the grassland boundary had retreated southward. Little vegetational change is evident during the last 3500 years. Calibration equations, derived from modern pollen and climatic data in the western interior of Canada and applied to an 11,400 year pollen record, suggest growing season temperature was 1.5°C greater than at present while growing season precipitation was 50 mm below current values during the middle Holocene.
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García, María Elena. "Aeropalinología de la ciudad de Yerba Buena, provincia de Tucumán (Argentina). Aeropalinology of Yerba Buena city, province of Tucumán (Argentina)." Acta Botanica Malacitana 35 (December 1, 2010): 115–31. http://dx.doi.org/10.24310/abm.v35i0.2870.
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Español. Durante los años 1999 - 2002 se llevó a cabo la primera caracterización aerobiológica de la ciudad de Yerba Buena. El muestreo atmosférico se realizó con un captador gravimétrico de tipo Durham. El análisis de las muestras permitió la identificación de 46 tipos polínicos. Los granos de polen más relevantes en el muestreo son de especies cultivadas como Cupressaceae, Morus sp., Broussonetia sp., Fraxinus sp., Liquidambar sp., Salix sp. y Pinus sp. Desde julio a octubre se obtuvo el mayor registro de polen atmosférico con el 70,84 % anual, con una predominancia de granos de polen de especies arbóreas, el 25,05 % de noviembre a abril con un aporte principalmente de granos de polen de especies herbáceas y el 3,57 % de mayo a junio sin contribuciones dominantes de algún tipo polínico. Se elaboró un calendario polínico basado en los 17 tipos de polen de mayor registro atmosférico y se lo comparó con calendarios polínicos obtenidos en ciudades del país. La floración en las Sierra del San Javier en Tucumán, es marcadamente estacional con una acumulación de más de 70% de las especies que florecen en el período primaveral. El muestreo continuado a lo largo de 3 años ha permitido observar que las variaciones polínicas estacionales de la atmósfera de la ciudad de Yerba Buena se hallan en relación con los factores fenológicos y meteorológicos propios de cada año. English. The first aerobiologic characterization of Yerba Buena city in Tucumán (Argentina) was carried out for the period 1999-2002 using a Durham gravimetric spore trap. The analysis of samples allowed the identification of 46 pollen types. The most outstanding pollen grains in these samples came from cultivated species such as Cupressaceae, Morus sp., Broussonetia sp., Fraxinus sp., Liquidambar sp., Salix sp.and Pinus sp. From July to October the largest atmospheric pollen records were obtained with 70,84% in arboreal species predominantly. From November to April, an important contribution of 25,05% in herbaceous species mainly, and with a 3,57% from May to June without observing predominant contribution of any pollen type. A pollen calendar based on the most frequent 17 pollen types, containing the largest atmospheric records, was elaborated. We compared the pollen calendar obtained with those of other cities in the country. Flowering in the Sierra San Javier at Tucumán is markedly seasonal with an accumulation of over 70% of the species that bloom in the spring period. Continuous sampling during 3 years has revealed that the seasonal pollen variation in the atmosphere of the city of Yerba Buena, is in connection with the phenological and meteorological factors characteristic of every year.
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Hicks, Sheila, Heather Tinsley, Antti Huusko, Christin Jensen, Martina Hättestrand, Achilles Gerasimides, and Eliso Kvavadze. "Some comments on spatial variation in arboreal pollen deposition: first records from the Pollen Monitoring Programme (PMP)." Review of Palaeobotany and Palynology 117, no. 1-3 (October 2001): 183–94. http://dx.doi.org/10.1016/s0034-6667(01)00086-0.
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Burney, David A. "Late Holocene Environmental Changes in Arid Southwestern Madagascar." Quaternary Research 40, no. 1 (July 1993): 98–106. http://dx.doi.org/10.1006/qres.1993.1060.
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AbstractA 5000-yr stratigraphic record containing fossil pollen, charcoal, and bones of the extinct Quaternary megafauna from Andolonomby, a hypersaline pond in arid southwestern Madagascar, shows evidence for climatic desiccation beginning about 3000 yr B.P. Pollen spectra shift at this time from primarily arboreal taxa characteristic of forests and woodlands of more mesic western Madagascar, to wooded savanna typical of somewhat drier localities. Between 3000 and 2000 yr B.P., the site became increasingly arid. Charcoal and pollen evidence indicates that increased fire and disturbance occurred at the site beginning ca. 1900 yr B.P., probably signaling the beginning of human settlement in the area. The fossil record suggests that various human and natural factors on the island may have interacted in the subsequent millennium to culminate in the extinction of the entire endemic megafauna.
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Webb, Thompson, G. Yoryos Yeracaris, and Pierre Richard. "Mapped patterns in sediment samples of modern pollen from southeastern Canada and northeastern United States." Géographie physique et Quaternaire 32, no. 2 (January 25, 2011): 163–76. http://dx.doi.org/10.7202/1000347ar.
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Isopoll maps based on 173 modern-pollen samples illustrate the geographical patterns of 12 pollen types within a 600,000 sq. km area centered in southern Québec. The mapped patterns reflect several scales of vegetational pattern that ranges from the major regional change between conifer-hardwood forest and boreal forest down to the minor local differences in vegetation between nearby sites. Picea and other arboreal pollen types are most representative of the regional patterns, whereas Cyperaceae and Ericaceae pollen often vary markedly between adjacent sites. Further analysis of these pollen data explored how much differences in sediment type and variations in analyst practices among the samples can affect the sensitivity of the pollen data to certain of the vegetational patterns. The set of 173 samples was divided into three subsets, two of which differ in sediment types and two of which differ in analyst practices. The distributions of pollen types are then correlated between the contrasting subsets, and their principal components are compared. These results show that only small differences exist among the subsets in their portrayal of the major vegetational patterns, but marked differences appear in the record of certain minor patterns.
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Atkinson, Helen, and Kjell-Arne Larsson. "A 10-year record of the arboreal airborne pollen in stockholm, sweden." Grana 29, no. 3 (January 1990): 229–37. http://dx.doi.org/10.1080/00173139009427756.
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Anderson, R. Scott, Gonzalo Jiménez-Moreno, Thomas Ager, and David F. Porinchu. "High-elevation paleoenvironmental change during MIS 6–4 in the central Rockies of Colorado as determined from pollen analysis." Quaternary Research 82, no. 3 (November 2014): 542–52. http://dx.doi.org/10.1016/j.yqres.2014.03.005.
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AbstractPaleoecological studies from Rocky Mountain (USA) high elevations encompassing the previous interglacial (MIS 5e) are rare. The ~10-m composite profile from the Ziegler Reservoir fossil site (2705 m asl) of central Colorado allows us to determine paleoenvironments from Marine Oxygen Isotope Stages (MIS) 6– 4 using pollen zones that are approximately equivalent to marine oxygen isotope stages. During Pollen Zone (PZ) 6 time, pollen assemblages dominated by Artemisia (sagebrush) suggest that alpine tundra or steppe occurred nearby. The transition to PZ 5e was characterized by a rapid increase in tree pollen, initially Picea (spruce) and Pinus (pine) but also Quercus (oak) and Pseudotsuga menziesii (Douglas-fir). Non-arboreal pollen (NAP) types increased during PZ 5d, while Abies (fir) and Juniperus (juniper) increased during PZ 5c. Pollen evidence suggests that temperatures during PZ 5b were as cold as during PZ 6, with the site again surrounded by alpine tundra. Picea dominated during PZ 5a before the onset of cooler conditions during PZ 4. The MIS 6–MIS 5e transition here was similar to the MIS 2–MIS 1 transition at other Rocky Mountain sites. However, the Ziegler Reservoir pollen record contains evidence suggesting unexpected climatic trends at this site, including a warmer-than-expected MIS 5d and cooler-than-expected MIS 5b.
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Hockey, Renae, Lachlan Wilmott, Lachlan Hall, and George Madani. "Novel field observations of eucalypt sap feeding behaviour in the Eastern Pygmy-possum Cercartetus nanus." Australian Zoologist 40, no. 2 (December 2019): 251–55. http://dx.doi.org/10.7882/az.2018.039.
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The Eastern Pygmy-possum Cercartetus nanu s is a small arboreal marsupial in the family Burramyidae that is threatened in parts of its range. Considered a generalist omnivore, its diet is known to include invertebrates, seeds, nectar and pollen. Tree sap has never before been recorded as a part of the diet of C. nanus . Here, we report on two observations of C. nanus feeding on eucalypt sap in south-eastern New South Wales.
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Bouchal, Johannes Martin, Tuncay Hüseyin Güner, and Thomas Denk. "Middle Miocene climate of southwestern Anatolia from multiple botanical proxies." Climate of the Past 14, no. 10 (October 17, 2018): 1427–40. http://dx.doi.org/10.5194/cp-14-1427-2018.
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Abstract. The middle Miocene climate transition (MMCT) was a phase of global cooling possibly linked to decreasing levels of atmospheric CO2. The MMCT coincided with the European Mammal Faunal Zone MN6. From this time, important biogeographic links between Anatolia and eastern Africa include the hominid Kenyapithecus. Vertebrate fossils suggested mixed open and forested landscapes under (sub)tropical seasonal climates for Anatolia. Here, we infer the palaeoclimate during the MMCT and the succeeding cooling phase for a middle Miocene (14.8–13.2 Ma) intramontane basin in southwestern Anatolia using three palaeobotanical proxies: (i) Köppen signatures based on the nearest living-relative principle; (ii) leaf physiognomy analysed with the Climate Leaf Analysis Multivariate Program (CLAMP); (iii) genus-level biogeographic affinities of fossil flora with modern regions. The three proxies reject tropical and hot subtropical climates for the MMCT of southwestern Anatolia and instead infer mild warm temperate C climates. Köppen signatures reject summer-dry Cs climates but cannot discriminate between fully humid Cf and winter-dry Cw; CLAMP reconstructs Cf climate based on the low X3.wet∕X3.dry ratio. Additionally, we assess whether the palaeobotanical record resolves transitions from the warm Miocene Climatic Optimum (MCO, 16.8–14.7 Ma) to the MMCT (14.7–13.9 Ma), and a more pronounced cooling at 13.9–13.8 Ma, as reconstructed from benthic stable isotope data. For southwestern Anatolia, we find that arboreal taxa predominate in MCO flora (MN5), whereas in MMCT flora (MN6) abundances of arboreal and non-arboreal elements strongly fluctuate, indicating higher structural complexity of the vegetation. Our data show a distinct pollen zone between MN6 and MN7+8 dominated by herbaceous taxa. The boundary between MN6 and MN7+8, roughly corresponding to a first abrupt cooling at 13.9–13.8 Ma, might be associated with this herb-rich pollen zone.
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Bennett, Joseph R., Brian F. Cumming, Peter R. Leavitt, Marian Chiu, John P. Smol, and Julian Szeicz. "Diatom, Pollen, and Chemical Evidence of Postglacial Climatic Change at Big Lake, South-Central British Columbia, Canada." Quaternary Research 55, no. 3 (May 2001): 332–43. http://dx.doi.org/10.1006/qres.2001.2227.
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AbstractPostglacial climatic conditions were inferred from cores taken from Big Lake in southern British Columbia. Low concentrations of nonarboreal pollen and pigments near the base of the core suggest that initial conditions were cool. Increases in both aquatic and terrestrial production suggest warmer and moister conditions until ∼8500 cal yr B.P. Hyposaline diatom assemblages, increases in nonarboreal pollen, and increased concentrations of pigments suggest the onset of arid conditions from ∼8500 to ∼7500 cal yr B.P. Slightly less arid conditions are inferred from ∼7500 until ∼6660 cal yr B.P. based on the diatoms, small increases and greater variability in biogenic silica and pigments, and higher percentages of arboreal pollen. At ∼6600 cal yr B.P., changes in diatoms, pigments, biogenic silica, and organic matter suggest that Big Lake became fresh, deep, and eutrophic until ∼3600 cal yr B.P., when water levels and nutrients decreased slightly. Our paleoclimatic inferences are similar to pollen-based studies until ∼6600 cal yr B.P. However, unlike these studies, our multiple lines of evidence from Big Lake imply large changes in effective moisture since 6000 cal yr B.P.
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Sharma, Chhaya, and Asha Gupta. "Vegetation and climate in Garhwal Himalaya during Early Holocene: Deoria Tal." Journal of Palaeosciences 46, no. 3 (December 31, 1997): 111–16. http://dx.doi.org/10.54991/jop.1997.1355.
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Pollen analysis of 1.5 m deep profile from the western flank of Deoria Tal (Profile-II), situated in temperate belt of Garhwal Himalaya has unravelled the vegetation and climate of Early Holocene. The vegetation, traced back to about 6000 years and 14C dated 2710±150 years at 55-65 cm depth, comprised chiefly the Oak dominated forests associated with other broad-leaved taxa such as Betula, Alnus, Rhododendron, Carpinus, Ulmus, etc. Such an arboreal forest composition reflects the warm-temperate humid climate prevalent in the region. A change to cooler climatic conditions is registered between 3500-3600 years B.P., as evidenced by the decline in Oak - the chief component, as well as in other associated broad-leaved elements with a corresponding rise in grasses and sedges. Anthropogenic activities are also recorded during this period, inferred by the first appearance of Cerealia-type pollen and encountered culture pollen. Subsequently, around 1,700 years B.P., the restoration process of Oak forests commenced, thus indicating the amelioration in climatic conditions.
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Karlıoğlu Kılıç, Nurgül. "Seven years of arboreal pollen monitoring in the İğneada waterlogged forests (NW Turkey)." Eurasian Journal of Forest Science 7, no. 3 (October 29, 2019): 311–20. http://dx.doi.org/10.31195/ejejfs.635736.
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Kim, Kae-Hwan, and Unsook Song. "A Contribution to the Pollen Morphology for Arboreal Type of Caesalpinioideae in Korea." Journal of Forest Research 3, no. 3 (August 1998): 175–79. http://dx.doi.org/10.1007/bf02762140.
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Mudavath, Chennakesavulu Naik, Jangam Ganga Kailas, Salamma Sugali, Devender Ravula, Ramakrishna Hari, and Ravi Prasad Rao Boyina. "The non-arboreal diversity of the Andaman Islands, India, based on pollen analysis." Palynology 41, no. 4 (April 10, 2017): 441–61. http://dx.doi.org/10.1080/01916122.2016.1257517.
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e Silva, Francisco Hilder Magalhães, and Francisco de Assis Ribeiro dos Santos. "Pollen morphology of the shrub and arboreal flora of mangroves of Northeastern Brazil." Wetlands Ecology and Management 17, no. 5 (October 7, 2008): 423–43. http://dx.doi.org/10.1007/s11273-008-9118-2.
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