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From its ‘modern’ pollen-analytical beginnings, the science of what we now term palynology wrestled with terminology and sought an acceptable name for the discipline. Starting in 1943, the mimeographed Pollen Analysis Circular, edited from Ohio by Paul Sears, led to discussion of the content, organisation and naming of a developing discipline. This came to a head in 1944 with Ernst Antev's plea for ‘The Right Word' and the suggestion of the word ‘palynology’ from the Cardiff duo of Harold Hyde and David Williams. In the search for a suitable term, Hyde consulted Cardiff-based Irish classicist Leopold Richardson who advised against the word palynology and suggested six alternatives. Hyde, however, was wedded to the term palynology and, in the interests of euphony and ‘hankering after my own offspring’, was seemingly able to overcome Richardson's scholarly objections by argument. Hyde and Williams defined palynology as ‘the study of pollen and other spores and their dispersal, and applications thereof’. This was considered an advance because alternative terms such as pollen analysis, pollen statistics and pollen science did not include the application or interpretation of pollen evidence. The term palynology quickly found acceptability within the pages of the Pollen Analysis Circular and subsequently received an airing in Nature. Once palynology was adopted by the influential Swede Gunnar Erdtman, it was rapidly accepted by the palaeoecological community.
Thirty surface samples collected from the Pakhiralaya area, south-western Ganges-Brahmaputra Delta, India, have been analysed for pollen in order to investigate modern pollen-vegetation relationships. Data on non-pollen palynomorphs (fungal spores, dinoflagellate cysts and algal cysts) were also obtained. There is currently a paucity of modern pollen studies from this region, which places limits on the interpretation of pollen data from other types of studies, for example studies aimed at understanding the Holocene vegetation history of this globally renowned tropical forest region. The local vegetation of the area is characterised by mangrove, marsh, herb and open land. The results of our study indicate that the pollen from locally growing taxa are the major components of modern pollen assemblages. Thus, pollen spectra show close linkages between modern pollen and local vegetation. Within the samples collected from the mangrove forest, the dominant mangrove taxa (Rhizophora mucronata, Bruguiera gymnorrhiza, Excoecaria agallocha, Sonneratia and Avicennia marina) are also the most frequently encountered pollen types, along with the mangrove associate taxa Thespesia sp., Pongamia pinnata and Phoenix paludosa. Thus, undisturbed mangrove forests are characterised mainly by a dominance of true mangrove and mangrove associate species in the pollen spectra. In contrast, pollen spectra from samples from ‘open land’ areas contained significant proportions of pollen from midland taxa. Anthropogenic impact on this area is captured in the samples through pollen of introduced plants such as Eucalyptus and Casuarina equisetifolia. The present study provides a basis for useful interpretation of Late Quaternary pollen sequences from the Ganges-Brahmaputra Delta, since modern pollen studies are still meagre in the poorly investigated delta region.
Fluorescence analysis of modern pollen grains is a well-established technique, but its use on fossil material is significantly less prevalent. A study focused on pollen and spore fluorescence and its indication was carried out using samples collected from a 14-m-deep exposed section at an abandoned fluvial terrace in the Khorat Plateau, the center of the Indochina peninsula. Fluorescent signals were well preserved in the deposits at various depths. Thirty-seven fluorescent pollen and spore taxa were discovered in six layers dated from Middle to Late Pleistocene. An alternative algorithm method was used to calculate the fluorescence intensity (FI) in the layers. The FI of each fossil pollen taxon, represented by an assigned value, is different among the layers throughout the section. Differences in the FI indicate varied preservation conditions. General linear analysis indicates that the total FI value is related to the pollen taxa but not to the deposit depth.
Honey bee (Apis mellifera) colony maintenance depends on foraging workers to obtain food resources from flowering plants year round. Because diverse floral diets have a positive impact on honey bee health, identifying the plants preferred by foragers provides valuable information to manage bee-friendly habitats. Recent studies have utilized palynology to better understand honey bee nectar foraging preferences. Futhermore, the International Honey Commission has established standards for analyzing honey samples. However, standards for studying the plant taxonomic composition of honey bee pollen pellets have not been established. The goal of this project was to determine the minimum number of pollen grains that need to be counted to obtain an accurate floral taxonomic representation in a pollen pellet sample. To do this, pollen samples were collected from pollen traps placed outside honey bee hives, and a pollen subsample foraged by each colony was acetolyzed and identified to the lowest taxonomic level possible. Cohorts of 100 pollen grains obtained from homogenized pollen samples from three different colonies were counted successively 5 times for a total count of 500 pollen grains per colony. This was repeated for each of the replicates from the three separate colonies. We found no statistically significant differences in the number or proportion of floral taxa found between the 200 and 500 pollen grain counts in two out of the three colonies sampled. Species diversity index analysis suggested that the higher number of floral taxa found in some 500-grain counts were attributed to a relatively low presence of minor pollen types. Thus, a 200 pollen grain count seems sufficient to assess the predominant, secondary and important minor plant taxa present in a pollen sample, while a 500-grain count may be needed to elucidate a more specific taxonomic assessment of additional minor taxa floral types to determine a sample's geographic origin.
This paper presents pollen morphology of 12 native Brazilian species of Rutaceae from forest fragments of São Paulo, Brazil. The aim of this research is to expand the morphological knowledge of the species, thus contributing to taxonomic knowledge and, subsequently, conservation of species and the forest area. The pollen grains were acetolyzed, measured, described qualitatively, and illustrated using light microscopy (LM) and scanning electron microscopy (SEM). The studied species have differences in polarity, size, shape, aperture and exine ornamentation of the pollen grains, confirming the eurypalynous character of Rutaceae pollen. In particular, species of Zanthoxylum L. also presented significant differences in the pollen grains, confirming the morphological variation within the genus. The quantitative data and multivariate analysis confirm the morphological description; thus, the results reinforce the importance of pollen morphology in the identification and characterization of species of Rutaceae.
The present communication deals with pollen analyses of moss polsters in order to understand the pollen rain from Udhampur District of Jammu and Kashmir, India. The study revealed that the pollen of Pinus sp. (average 46% pollen) dominates the pollen rain, which could be attributed to its high pollen productivity and excellent pollen dispersal efficiency, followed by Cedrus sp., and Podocarpus sp. However, other conifers such as Abies sp., Picea sp., Juniperus sp. and Tsuga sp., as well as the broad-leaved taxa such Alnus sp., Betula sp., Ulmus sp., Quercus sp., Carpinus sp., Corylus sp., Juglans sp., Ilex sp., Mallotus sp., Elaeocarpus sp. and Aesculus sp., were sporadically recorded which could be due to either their poor pollen dispersal efficiency or poor preservation in the substrate. Tubuliflorae, Poaceae, Amaranthaceae, Malvaceae and Cerealia are the other prominent taxa of the pollen rain, revealing their actual composition in the ground vegetation.
Pollen diagrams from three areas of the Kenai Lowland of Alaska demonstrate the pollen floras of the Clamgulchian Stage (∼8-2.5 Ma) of Late Miocene/Early Pliocene age. These sections, originally described based on their plant megafossils and pollen, are revisited for a more precise determination of their pollen stratigraphy. The floras from Clam Gulch on the west margin of the Kenai Lowland are compared with Clamgulchian sections of the same age on the east margin, in canyons at the head of Kachemak Bay. The results substantiate that in the Clamgulchian sections thermophile pollen types (exotic warmth-loving woody genera) represent about 2–10% of the count (and include 15 thermophile taxa), while in the earlier Homerian Stage (∼14.5-8 Ma) thermophiles are more important and more diverse (28 taxa), representing 5–15% of the count. A second difference between the Homerian and Clamgulchian is the increased diversity of herbaceous groups (such as Ranunculaceae, Urticaceae, Onagraceae, Primulaceae and others), which are few in the Homerian (∼4–5 taxa), but many in the Clamgulchian (≤15–18 taxa). These herb groups show increasing diversity near the top of the Neogene in the Alaskan flora. With a decrease in thermophiles, the Clamgulchian taxa show a transition towards a cooler climate. Pollen of the exotic gymnosperm family Podocarpaceae chiefly of the Southern Hemisphere are diverse minor elements during the entire Neogene of Alaska. These consistent elements may represent resident associates of the hardwood forests in southern Alaska as the likelihood of their pollen occurrences being the result of long-distance transport seems unlikely.
A large amount of palynological research has been undertaken on the Late Cretaceous—Paleocene strata of the plains area of southern Alberta. The present study is a summary of the palynoflora encountered in individual rock units across the region. Previous palynological research has been summarized and a brief summary of the geology of the region provided. A large number of taxa have been identified with many not as yet described. Important palynomorph taxa are illustrated along with a tabulation of all the species identified to date for each stratigraphic unit. A biostratigraphic scheme is proposed with 19 biozones described. Not all of these biozones are present in Alberta and information has been taken from materials in Saskatchewan, Canada, and Montana, United States.
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