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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Ch3- Palynology

Wai Kehadeezbah Allen (14671736) 17 May 2024 (has links)
<p>This dataset contains results of a palynological study completed by Dr. Robert L. Raven from the IRF Group Inc in December 29, 2018</p> <p><br></p> <p>Palynological analysis was performed on siltstone samples that were collected from 4 outcrops of cenozoic strata from the study area of Chapter 3 in the eastern Alaska Range. This file includes the results of that study and detail about he present pollen assemblages as well as images</p> <p><br></p> <p>Jeffrey Benowitz contracted this work</p>
122

ABSOLUTE POLLEN FREQUENCIES APPLIED TO THE INTERPRETATION OF HUMAN ACTIVITIES IN NORTHERN ARIZONA

Kelso, Gerald Kay, 1937- January 1976 (has links)
No description available.
123

Paläoökologische Untersuchungen zur spätglazialen und holozänen Landschaftsgenese des Ostschwarzwaldes im Vergleich mit den Buntsandsteinvogesen /

Sudhaus, Dirk. January 2005 (has links)
Thesis (doctoral)--Universität, Freiburg im Breisgau, 2005. / University publication. Includes bibliographical references (p. 137-151).
124

Some Palynological Applications of Multivariate Statistics

Adam, David Peter January 1970 (has links)
Palynology involves the study of past climatic and environmental changes through changes in the relative frequencies of different pollen types through time. Several multivariate statistical methods are suggested which can help in the description of patterns within pollen data. These techniques are based on comparisons between samples. Samples were compared using the product-moment correlation coefficient computed from data which had been subjected to a centering transformation. The methods are described using a geometric model. If there are m samples and n pollen types, then the data can be regarded as a set of m points in an n-dimensional space. Cluster analysis produces a dendrograph or clustering tree in which samples are grouped with other samples on the basis of their similarity to each other. Principal component analysis produces a set of variates which are linear combinations of the pollen samples, are uncorrelated with each other, and do the best job of describing the data using a minimum number of dimensions. This method is useful in reducing the dimensionality of data sets. Varimax rotation acts on a subset of the principal components to make them easier to interpret. Discriminant analysis is used to find the best way to tell groups of samples apart, where the groups are known a priori. Once a means of discrimination among groups has been established using samples whose groups are known, unknown samples may be classified into the original groups. Canonical analysis produces a way to display the maximum separation between groups in a graphic manner. Examples of applications of these methods in palynology are shown using data from Osgood Swamp, California, and from southern Arizona. These methods offer the advantages of reproducibility of results and speed in pattern description. Once the patterns in the data have been described, however, their interpretation must be done by the palynologist.
125

The environment of Miami Wash, Gila County, Arizona, A. D. 1100 to 1400

Lytle-Webb, Jamie January 1978 (has links)
No description available.
126

A palynological study of Heliophila (Brassicaceae) in southern Africa

Kumwenda, Mphamba Wayera 04 1900 (has links)
On t.p.: Systematics and Biodiversity Science. / Thesis (MSc)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: Pollen grains of the southern African genus Heliophila L. (Brassicaceae), were examined using light microscopy (77 taxa), scanning electron microscopy (82 taxa) and transmission electron microscopy (IOtaxa). The present study emanates from a pilot study by Kose (200 I) in which palynology was identified as one of the taxonomically informative data sources that can be used in the classification and subdivision of the genus Heliophila. The aim of this study was to assess the taxonomic significance of palynological data in the genus Heliophila. All pollen grains of Heliophila taxa are prolate in shape and tricolpate. The exine surface sculpture varies and two main groups are identified. In the majority of the taxa the sculpture is psilate or psilate micro-perforate with suprateetal spinules (Pollen Type A), whereas in the remaining taxa the sculpture is micro-reticulate to reticulate with or without suprateetal spinules (Pollen Type B). Pollen Type B may be divided further into three subgroups based on the shape of the lumina and the position of the suprateetal spinules. TEM results also confirm the two main groups as proposed by the SEM. The structural and sculptural features of the exine proved important in the demarcation of the pollen grains into two distinctively different pollen types and the other pollen morphological data such as pollen grain sizes, pollen grain shape are discussed in relation to the groups/subgroups of pollen types. The sculpturing types are discussed with regard to their evolution and pollination discussed with regard to plant habit and pollen size. Cluster analysis, based on vegetative and reproductive characters, excluding palynological characters, was performed only after the pollen types were identified. These groups were well supported by plant habit, life form, leaf type, presence or absence of appendages on the filaments, indumentum of filaments and presence of the stipe on the ovary and divided the genus Heliophila into two main clades. It was observed that this division followed a sim ilar pattern as the species arrangement in the classification by Marais (1970). AIthough the two main pollen types occur in both clusters proposed by the morphological analysis, the specific pollen types are restricted to distinct subclusters. In conclusion, pollen data reveals that Heliophila is a heterogeneous genus. The present study also reveals that it is difficult to subdivide the Heliophila taxa into infrageneric units on the basis of palynological evidence alone. In conjunction with other data sources, it does, however appear to have systematic significance. Therefore, the results of the present palynological study can be used as an additional source of evidence to support the subdivision of the Heliophila taxa into infrageneric units in the near future if a better understandinz and classification of the zenus is to b b be achieved. / AFRIKAANSE OPSOMMING: Stuifmeelkorrels van die suider Afrikaanse genus Heliophila L. (Brassicaceae) is met behulp van ligmikroskopie (77 taksons), skandeerelektronmikroskopie (82 taksons) en transmissie-elektronmikroskopie (IOtaksons) bestudeer. Die huidige studie is 'n uitvloeisel van 'n lootsprojek deur Kose (200 I) waarin palinologie geïdentifiseer is as een van die taksonomies-belangrike data-bronne wat in die klassifikasie en subdivisie van die genus Heliophila gebruik kan word. Die doel van die studie was om die taksonomiese waarde van palinologiese data van die genus Hettophila te bepaal. Alle stuifmeelkorrels van Heliophila taksons is prolaat in vorm en trikolpaat. Die oppervlak-skulptuur van die eksien varieer en twee hoofgroepe word onderskei. In die meerderheid van die taksons is die skulptuur psilaat of psilaat-mikroperforaat met supratektale uitsteeksels (stuifmeeltipe A), terwyl die skulptuur in die oorblywende taksons rnikro-retikulaat tot retikulaat met of sonder supratektale uitsteeksels (stuifmeeltipe B) is. Stuifmeeltipe B kan verder in drie subgroepe, gebaseer op die vorm van die lumens en die posisie van die supratektale uitsteeksels, verdeel word. Resultate verkry vanaf die TEM bevestig die twee hoofgroepe soos voorgestel deur die SEM-studies. Die strukturele en skulpturele kenmerke van die eksien blyk belangrik te wees in die verdeling van die stuifmeelstruktuur in twee duidelike stuifmeeltipes en ander morfologiese kenmerke, byvoorbeeld die grootte en vorm van die stuifmeelkorrels word bespreek in hul verhouding tot die groepe / subgroepe van die stuifmeeltipes. Die tipes stuifmeel-skulptuur word bespreek ten opsigte van hul evolusie en bestuiwing word bespreek ten opsigte van groeiwyse en stuifmeelgroottes. Groepanalise, gebaseer op vegetatiewe en reproduktiewe kenmerke, uitsluitend palinologiese kenmerke, is saamgestel nadat die stuifmeeltipes geïdentifiseer is. Die groepe word gevorm op grond van groeiwyse, groeivorm, blaartipe, aan- of afwesigheid van aanhangsels aan die helmdrade, die indumentum van die helmdrade en die aanwesigheid van 'n stipe op die vrugbeginsel en verdeel die genus Heliophila in twee hoofgroepe. Daar is waargeneem dat hierdie analise 'n soortgelyke patroon volg as die spesie-rangskikking in die klassifikasie van Marais (1970). Alhoewel die twee stuifmeeltipes in beide die morfologiese hoofgroepe aanwesig is, stem die stuifmeeltipes duidelike ooreen met die sub-groepe wat deur die morfologiese analise gevorm is. Ten slotte, stuifmeeldata dui daarop dat Heliophila 'n heterogene genus is. Die huidige studie dui ook daarop dat' n onderverdeling van Heliophila in infrageneriese eenhede op grond van palinologiese kenmerke alleen ook baie moeilik is, maar saam met ander kenmerke kan stuifmeeldata wel van taksonomiese waarde wees. Dus, die resultate van hierdie studie kan as 'n aanvullende bron van data gebruik word om 'n onderverdeling van die genus te steun en 'n klassifikasie van die genus daar te stel.
127

Vegetation and climate of north anatolian and north aegean region since 7 Ma according to pollen analysis

Biltekin, Demet 21 December 2010 (has links) (PDF)
This study concerns a long marine section (DSDP Site 380: Late Miocene to Present) and onshore exposed sections from the Late Miocene and/or Early Pliocene. The main target of this study is to reconstruct vegetation and climate in the North Anatolia and North Aegean region for the last 7 Ma. Two vegetation types were alternately dominant: thermophilous forests and open vegetations including Artemisia steppes. During the Late Miocene, most of the tropical and subtropical plants declined because of the climatic deterioration. However, some of them survived during the Late Pliocene, such as those which constituted coastal swamp forests (Glyptostrobus, Engelhardia, Sapotaceae, Nyssa) or composed deciduous mixed forests with mesothermic trees. Simultaneously, herbaceous assemblages became a prevalent vegetation component despite steppe elements (Artemisia, Ephedra, Hippophae rhamnoides) did not significantly develop. At 2.6 Ma, as a response to the onset of Arctic glaciations, subtropical elements rarefied despite some taxa persisted (Glyptostrobus, Engelhardia, Sapotaceae, Nyssa). In parallel, deciduous mixed forest assemblages composed of mesothermic trees (deciduous Quercus, Betula, Alnus, Liquidambar, Fagus, Carpinus, Tilia, Acer, Ulmus, Zelkova, Carya, Pterocarya) almost disappeared too while steppe environments strongly enlarged. Then, Artemisia steppic phases developed during longer temporal intervals than mesophilous tree phases all along the glacial-interglacial cycles (first with a period of 41 kyrs, then 100 kyrs). Since 1.8 Ma, herbaceous ecosystems including Artemisia steppes still continuously enlarged up today. Such an expansion of Artemisia steppes in the Ponto-Euxinian region was observed at the earliest Pliocene but their earliest settlement in Anatolia seems to have occurred in the Early Miocene. The development of the Artemisa steppes in Anatolia might result from the uplift of the Tibetan Plateau. Relictuous plants such as Carpinus orientalis, Pterocarya, Liquidambar orientalis, Zelkova persisted up today. This story can be explained by some influence of the Asian monsoon which reinforced as a result from the uplifted Tibetan Plateau.
128

Late quaternary vegetation and climate dynamics in western amazonia

Rodriguez Zorro, Paula Andrea 15 March 2017 (has links)
No description available.
129

Postglaciální historie lokálních fenoménů horské vegetace západních Čech / Postglacial vegetation history of local phenomena in western Bohemia

Švarcová, Markéta Gabriela January 2012 (has links)
In the sense of postglacial vegetation development, western Bohemia represents one of the least studied regions in the Czech Republic. This area, however, represents a supposed migration route of trees towards northern Europe during the Holocene. The most appropriate area for testing of such proposal might be western Sudetes with Slavkovský les protected landscape area in the Karlovy Vary region. Postglacial vegetation history was studied on the basis of two sedimentary profiles - from the fen bog near Číhanské prameny springs and from the vicinity of Mnichovské hadce serpentines from the nature reserve Mokřady pod Vlčkem. Percentual as well as influx diagrams were constructed on the basis of results of standard pollen analysis. Comparison of these results with the data from other suitable profiles enabled reconstruction of migration history of main tree taxa. The Číhaná profile reflects the period from the Older Dryas up to the Atlantic. The oldest Holocene forest was formed by the dominant Pinus, while Corylus was joining already in the Preboreal. Quercetum mixtum folowed in the begining of the Boreal and spruce quickly gained dominance in the Atlantic. The sedimentation process was probably finished due to rapid accumulation of sediments followed by spontaneous drainage ending with spruce and alder...
130

Palinotaxonomia de espécies brasileiras de Sinningia Nees (Gesneriaceae) - evolução da morfologia polínica e síndromes de polinização / Palinotaxonomy in brazilian species of Sinningia Nees (Gesneriaceae) - evolution of pollen morphology and pollination syndromes

Dutra, Fernanda Vitorete 24 September 2018 (has links)
Gesneriaceae é uma das famílias mais antigas da ordem Lamiales e possuí aproximadamente 150 gêneros, entre eles, Sinningia Nees, com um grande número de espécies endêmicas do Brasil. Foram estudados os grãos de pólen de 27 espécies brasileiras de Sinningia com o objetivo de caracterizar e identificar dados polínicos que possam auxiliar na taxonomia da família, ampliando os conhecimentos sobre a diversidade polínica do gênero, a fim de fornecer subsídios para o melhor entendimento das relações entre as espécies e da evolução dos caracteres polínicos, assim como relacionar os dados obtidos nesse trabalho com as síndromes de polinização descritas para o gênero. O material analisado foi obtido a partir de espécimes depositados nos herbários SP, MBM, MBML, ESA, UEC e INPA e de material de cultivo do Sítio Primavera em Mogi das Cruzes SP. Os grãos de pólen foram acetolisados, medidos, fotografados em microscopia óptica, microscopia eletrônica de varredura e transmissão e descritos qualitativamente. Os dados quantitativos foram analisados por meio de estatísticas descritiva e multivariada. Para as espécies brasileiras de Sinningia estudadas foram observadas variações entre os grãos de pólen, principalmente quanto ao tamanho, âmbito, forma, comprimento dos colpos e ornamentação. Foram encontrados grãos de pólen pequenos, pequenos à médios e médios; isopolares; âmbito circular, circular-lobados, subcircular e subtriangular; oblato-esferoidais, prolato-esferoidais, subprolatos e prolatos; área polar muito pequena, pequena ou grande; 3-colporados; colpos muito curtos, curtos, longos e muito longos e estreitos; colpos às vezes contritos na região mediana; endoabertura lolongadas; exina microrreticulada heterobrocada e homobrocada. Os dados obtidos confirmam o caráter estenopolínico do gênero, uma vez que as diferenças encontradas nos grãos de pólen são discretas e não permitem a identificação intragenérica. / Gesnericeae is one of the oldest families of the order Lamiales and has approximately 150 genera, among them, Sinningia Nees, that owns a great number of species endemic of Brazil. We studied the pollen grains of 27 Brazilian Sinningia with the objective of characterizing and identifying pollen data that could aid in family taxonomy, knowledge on pollen diversity of the genus,in order to provide support for a better understanding of the relationships between species and the evolution of pollinic characters, as well as to relate the data obtained in this work to the pollination syndromes described for the genus. The material analyzed was obtained from the specimens deposited in the herbaria SP, MBM, MBML, ESA, UEC and INPA and of cultive material of the Sítio Primavera in Mogi das Cruzes SP. The pollen grains were acetolysed, measured, photographed under light microscopy, scanning and transmission electron microscopy and described qualitatively. The quantitative data were analyzed by descriptive and multivariate statistics. For the Brazilian Sinningia species studied, variations were observed between pollen grains, mainly in the size, amb, shape, length colpi and ornamentation. The pollen grains are small, small to medium and medium; isopolar; circular, circular-lobate, subcircular and subtriangular amb; oblate-spheroidal, prolate-spheroidal, subprolate and prolate; polar area is very small, small or large; 3-colporate; very short, short, long and very long colpi and narrows; sometimes contrite in the median region; lolongate endoaberture; heterobrocate and homobrocate microrreticulate ornamentation. The data obtained confirm the stenopalynous character of the genus, since the differences found in the pollen grains are discrete and do not allow intrageneric identification.

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