Foram estudadas a morfologia polínica de 20 espécies de Beslerieae Bartl. (Anetanthus, Besleria e Tylopsacas) e quatro espécies de Napeantheae Wiehler (Napeanthus), nativas no território brasileiro e encontradas principalmente nos biomas da Amazônia e/ou Mata Atlântica. O objetivo deste trabalho é contribuir com a caracterização morfológica das espécies, identificando dados polínicos que possam auxiliar na taxonomia do grupo, ampliando desta forma os conhecimentos sobre a diversidade polínica nos gêneros estudados e fornecendo subsídios para o melhor entendimento das relações entre as tribos brasileiras de Gesneriaceae e da evolução dos caracteres polínicos nestes gêneros. Também foi discutida a relação entre a morfologia polínica de Besleria e sua distribuição fitogeográfica. O material analisado foi obtido a partir de espécimes depositados nos herbários INPA, SP e MBM. 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. Os grãos de pólen são mônades; isopolares; de tamanho pequeno; com grande variação de forma, podendo ser, oblatos, suboblatos, oblatos-esferoidais, prolatos-esferoidais, subprolatos ou prolatos; âmbitos circulares, circulares-lobados, subcirculares a subtriangulares. As aberturas são 3-colpadas, 3- (4) colpadas ou 3-colporadas; colpos longos, curtos ou muito curtos; estreitos a largos; extremidades afiladas ou arredondadas, algumas vezes possuindo margem, colpo constrito ou membrana ornamentada; endoabertura predominantemente lolongada, as vezes circulares. Ornamentação da exina fossulada, microrreticulada, microrreticulada-rugulada, microrreticulada-fossulada, rugulada, rugulada-perfurada. Exina variando de muito fina, fina a espessa, sexina sempre mais espessa que a nexina. Variações no tipo de abertura e nos padrões da ornamentação da exina dos grãos de pólen contribuíram para a distinção das espécies estudadas e confirmam o caráter euripolínico de Beslerieae e Napeantheae. / The pollen morphology of 24 Brazilian species of Beslerieae Bartl. (Anetanthus, Besleria and Tylopsacas) and Napeantheae Wiehler (Napeanthus) was studied, these species are native to the Amazon and / or Atlantic Forest biomes. The objective of this study is to contribute to the morphological characterization of the species, identifying pollen data that may help in the taxonomy of the group, thus increasing the knowledge about the pollen diversity and evolution in the studied genera and providing subsidies for a better understanding of the relations between the Brazilian tribes of Gesneriaceae. Also we discussed the relationship between the pollen morphology of Besleria and its phytogeographic distribution. The material analyzed was obtained from specimens deposited in the INPA, SP and MBM herbaria. The pollen grains were acetolysed, measured, photographed under light microscopy, scanning and transmission electron microscopy and described qualitatively. Quantitative data were analyzed using descriptive and multivariate statistics. The pollen grains are monads; isopolar; small size; with variation in shape, oblate, suboblate, oblate-spheroidal, prolate-spheroidal, subprolate or prolate; circular, circular-lobed, subcircular to subtriangular amb. The apertures are 3-colpate, 3-(4) colpate or 3-colporate; long, short or very short colpi and narrow to wide; with or without margo, rounded or tapered at the polar ends, sometimes constricted or with ornate membrane; endoapertures lolongate or circular. Exine fossulate, microrreticulate, microreticulate-rugulate, microreticulate-fossulate, rugulate, rugulate-perforate. Very thin, thin to thick exine, sexine always thicker than nexin. Variations in the type of aperture and patterns of exine ornamentation of the pollen grains contributed to the distinction of the species studied and confirmed the eurypalynous character of Beslerieae and Napeantheae.

A Bacia do Espírito Santo possui importantes campos de petróleo e gás em exploração, entretanto poucos trabalhos micropaleontológicos estão disponíveis para esta região uma vez que a maior parte deste conhecimento é relativo a relatórios internos de empresas de petróleo e gás. Este trabalho apresenta uma análise bioestratigráfica e paleoambiental de sucessões sedimentares do intervalo Aptiano-Albiano das formações Mariricu (Membro Itaúnas), São Mateus e Regência. A amostragem é derivada de dois poços (BES-01 e BES-02) perfurados na porção emersa da bacia. Dentre as 24 amostras, 18 revelaram assembleias palinológicas diversificadas, incluindo 51 táxons de plantas terrestres (23 de esporos e 28 de grãos de pólen), 4 táxons de algas (3 dinocistos e 1 alga clorofícea), bem como táxons não determinados de palinoforaminíferos, fungos, escolecodontes e acritarcos. Os grãos de pólen de gimnospermas são dominantes em ambos os poços, principalmente representados pela abundância e diversidade de Classopollis; outros gêneros de grãos de pólen e esporos ocorrem subordinados. A análise bioestratigráfica se baseou nos intervalos cronoestratigráficos de espécies-guias comparadas com biozoneamentos estabelecidos principalmente para a própria Bacia do Espírito Santo, como também para as demais bacias marginais brasileiras As amostras do BES-01 apresentaram idade Albiano inferior, enquanto para as amostras do poço BES-02 foi atribuída idades entre o Aptiano superior e o Albiano inferior (sem distinção). Os dinocistos e os palinoforaminíferos são restritos a alguns níveis do poço BES-01; a assembleia monoespecífica distinta do gênero Subtilisphaera representa o primeiro registro da Ecozona Subtilisphaera na Bacia do Espírito Santo, indicando a ocorrência mais ao sul desta ecozona nas bacias marginais brasileiras. Comparando a frequência da matéria orgânica particulada nas amostras (palinomorfos, fitoclastos e matéria orgânica amorfa), se interpretou o ambiente deposicional como uma região costeira ocasionalmente influenciada por transgressões marinhas. A palinoflora representa a fase final da Província Dicheiropollis etruscus/Afropollis documentada em várias bacias marginais no Brasil e na África, principalmente definida por elementos gimnospérmicos fortemente adaptados a condições climáticas quentes e secas. / The Espírito Santo Basin comprises important oil and gas fields, mostly in active exploration. However, few micropaleontological contributions are available for this region, once most part of its knowledge is concerning to internal reports of oil and gas companies. This work presents a biostratigraphic and paleoenvironmental analysis from an Aptian-Albian succession of Mariricu (Itaúnas Member), São Mateus and Regência formations. Sampling is derived from two wells (BES-01 and BES-02), drilled in the onshore portion of the basin. Among 24 samples, 18 revealed abundant and diverse assemblages of palynomorphs, including 51 taxa related to terrestrial plants (23 of fern spores, and 28 of gimnospermic pollen grains), 4 algae (3 of dinocysts and 1 chlorophicean), as well as no determined taxa of foraminiferal linings, fungi, scolecodonts and acritarch. Gimnospermic pollen grains are dominant in both wells, mainly represented by an expressive abundance and diversity of Classopollis; other gimnospermic pollen grains and pteridophitic spores are subordinate. Biostratigraphic assignments are based on the ranges of certain guide species compared with schemes mainly established for the Espírito Santo Basin, as well as to other Brazilian marginal basins The samples of BES-01 were defined as early Albian in age, whereas an age from late Aptian to early Albian (without distinction) was assigned for the samples of well BES-02. Dinocysts (mainly Subtilisphaera) and foraminiferal linings are restricted to certain levels of the well BES-01. A distinctive monospecific assemblage of the Subtilisphaera in some samples reflects the first record of the Subtilisphaera Ecozone in the Espírito Santo Basin, representing its most meridional occurrence in the Brazilian marginal basins. Comparing the frequency of palynological content in both wells (palynomorphs, phytoclasts and amorphous organic matter), the depositional environment is interpreted as a coastal area, episodically influenced by marine transgressions. The palynofloral content of the assemblages is assumed to represent the final stage of the Dicheiropollis etruscus/Afropollis Province, which is well documented in several marginal basins of Brazil and Africa, mainly defined by a gimnospermic elements, strongly adapted to warm and dry climate conditions.

Foram estudadas a morfologia polínica de 20 espécies de Beslerieae Bartl. (Anetanthus, Besleria e Tylopsacas) e quatro espécies de Napeantheae Wiehler (Napeanthus), nativas no território brasileiro e encontradas principalmente nos biomas da Amazônia e/ou Mata Atlântica. O objetivo deste trabalho é contribuir com a caracterização morfológica das espécies, identificando dados polínicos que possam auxiliar na taxonomia do grupo, ampliando desta forma os conhecimentos sobre a diversidade polínica nos gêneros estudados e fornecendo subsídios para o melhor entendimento das relações entre as tribos brasileiras de Gesneriaceae e da evolução dos caracteres polínicos nestes gêneros. Também foi discutida a relação entre a morfologia polínica de Besleria e sua distribuição fitogeográfica. O material analisado foi obtido a partir de espécimes depositados nos herbários INPA, SP e MBM. 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. Os grãos de pólen são mônades; isopolares; de tamanho pequeno; com grande variação de forma, podendo ser, oblatos, suboblatos, oblatos-esferoidais, prolatos-esferoidais, subprolatos ou prolatos; âmbitos circulares, circulares-lobados, subcirculares a subtriangulares. As aberturas são 3-colpadas, 3- (4) colpadas ou 3-colporadas; colpos longos, curtos ou muito curtos; estreitos a largos; extremidades afiladas ou arredondadas, algumas vezes possuindo margem, colpo constrito ou membrana ornamentada; endoabertura predominantemente lolongada, as vezes circulares. Ornamentação da exina fossulada, microrreticulada, microrreticulada-rugulada, microrreticulada-fossulada, rugulada, rugulada-perfurada. Exina variando de muito fina, fina a espessa, sexina sempre mais espessa que a nexina. Variações no tipo de abertura e nos padrões da ornamentação da exina dos grãos de pólen contribuíram para a distinção das espécies estudadas e confirmam o caráter euripolínico de Beslerieae e Napeantheae. / The pollen morphology of 24 Brazilian species of Beslerieae Bartl. (Anetanthus, Besleria and Tylopsacas) and Napeantheae Wiehler (Napeanthus) was studied, these species are native to the Amazon and / or Atlantic Forest biomes. The objective of this study is to contribute to the morphological characterization of the species, identifying pollen data that may help in the taxonomy of the group, thus increasing the knowledge about the pollen diversity and evolution in the studied genera and providing subsidies for a better understanding of the relations between the Brazilian tribes of Gesneriaceae. Also we discussed the relationship between the pollen morphology of Besleria and its phytogeographic distribution. The material analyzed was obtained from specimens deposited in the INPA, SP and MBM herbaria. The pollen grains were acetolysed, measured, photographed under light microscopy, scanning and transmission electron microscopy and described qualitatively. Quantitative data were analyzed using descriptive and multivariate statistics. The pollen grains are monads; isopolar; small size; with variation in shape, oblate, suboblate, oblate-spheroidal, prolate-spheroidal, subprolate or prolate; circular, circular-lobed, subcircular to subtriangular amb. The apertures are 3-colpate, 3-(4) colpate or 3-colporate; long, short or very short colpi and narrow to wide; with or without margo, rounded or tapered at the polar ends, sometimes constricted or with ornate membrane; endoapertures lolongate or circular. Exine fossulate, microrreticulate, microreticulate-rugulate, microreticulate-fossulate, rugulate, rugulate-perforate. Very thin, thin to thick exine, sexine always thicker than nexin. Variations in the type of aperture and patterns of exine ornamentation of the pollen grains contributed to the distinction of the species studied and confirmed the eurypalynous character of Beslerieae and Napeantheae.

New Zealand forest has been affected by both natural and anthropogenic disturbances. Protecting and restoring indigenous forest is one of the focal issues in conservation of New Zealand, and understanding vegetation dynamics is a key part of management strategies. The longevity of most of New Zealand trees impedes short-term vegetation dynamic studies. Instead fossil pollen records provide one of the most valuable sources of long term data to trace vegetation development. In this study, pollen records are used as proxies of vegetation population to test the roles of long-term climate change and transient environmental disturbances in vegetation dynamics. Two sediment cores, from Sponge Swamp, Haast, and Tiniroto Lakes, Gisborne, were collected as representatives of undisturbed and disturbed sites, the former being used as a reference site to separate out the effects of climate and evaluate the impact of disturbance on the vegetation. Pollen data were inspected using Tilia, and zones defined. Principal component analysis (PCA) was performed on pollen data to summarise the change in species composition over time, and the sample scores of the first PCA axis were exploited as an index of vegetation dynamics for further comparison. Redundancy analysis (RDA) is also applied to help interpretation of the vegetation change with respect to environmental factors. The result of this study indicates that the vegetation development in both sites is characterized by non-equilibrium dynamics, in which vegetation composition is changing continually through time. In Sponge Swamp, this change is steady and consistent over the whole time span, with a consistent decline of Ascarina lucida and a progressive increase of cold tolerant or moisture-stressed taxa, like Gleichenia and Lycopodium australianum. Subsequently there is a partial replacement of swamp forest taxa such as Dacrycarps dacrydioides and tree ferns by Prumnopitys taxifolia, and further expansion of Nothofagus and Phyllocladus is distinguished. A climate gradient, from mild and wet to cooler and/or drier is suggested from the pollen evidence, and appears the driving force for the vegetation dynamics at that undisturbed site. At Tiniroto, however, the vegetation development is divided into two stages. Before c. 2300 yr BP, the vegetation change is steady and consistent which is comparable to that from Sponge Swamp. A forest invasion, a process of gradually replacing open land and light-adapted taxa, such as Dodonaea viscosa, Coprosma, Pseudopanax, Schefflera digitata, Pteridium, Hebe and members of the family Fabaceae and Asteraceae, by increasing proportions of forest taxa, characterise this change. Climate amelioration with increased rainfall is responsible. After c. 2300 yr BP, this trend was frequently punctuated by disturbances, in which sudden changes of vegetation occur, generating substantial fluctuations about the trend. From RDA, sample age explains more than 20% of the variance of species data at both sites. The long-term directional climate change derived from pollen evidence of Sponge Swamp and at least partly at the Tiniroto site, may be represented by the explanatory variable age. At Tiniroto, additional variance is also explained by the explanatory variables charcoal and pollen taxonomic richness, suggesting the impact of disturbance on vegetation dynamics. The impact of disturbance on vegetation dynamics becomes clearer after the climate gradient is removed. Autocorrelation analysis on detrended sample scores of the first PCA axis suggests further differences between the two sites, in response to local disturbances. There is little dependence of the present state of vegetation composition on its past state in the Sponge Swamp site; instead, the vegetation composition is affected by various "random" events, implying small disturbances such as floods, or landslides caused by earthquakes etc. At Tiniroto, the change of vegetation composition is more "successional", and the present state of vegetation depends only on the immediate past state, due to the impact of catastrophic disturbance. Despite the Tiniroto site having been subjected to a long history of disturbance, the climate gradient, which is distinct at the earlier stage, becomes less identifiable and partially masked by outbreaks of disturbances only since c. 2300 yr BP. This implies that the relative role of disturbance on vegetation dynamics with respect to climate is depended on different types or different levels of disturbances and different responses by the vegetation. Short-term vegetation responses to different types of disturbance were examined by fine resolution pollen analyses around five disturbance episodes, including the Taupo (1850±10 yr BP), Waimihia (3280±20 yr BP), Whakatane (4830±20 yr BP) eruptions, and two charcoal peaks (c. 1100 yr BP and c. 2300 yr BP). Almost no vegetation change occurred relative to the eruption within the Whakatane and Waimihia episodes, except that a temporary rise of shrubs and ferns corresponded with intermittent occurrence of charcoal particles. Substantial vegetation change relative to disturbance was found within both the Taupo episode and the fire episode around c. 2300 yr BP, in which establishment of ensuing semi-open vegetation was encouraged for decades. The fire c. 2300 yr BP transformed part of the forest into fernland, while the Taupo eruption turned part of the shrubs and tree ferns into bracken field. Although it is difficult to judge the effect of the fire around 1100 yr BP as the result was unreliable due to contamination, the vegetation at Tiniroto is suggested to be more vulnerable to fire than tephra. Non-equilibrium dynamics are common in New Zealand forests, even at stable sites such as Sponge Swamp, due to climate change. Locally these non-equilibrium dynamics appear highly responsive to disturbances, esp. at Tiniroto. Even disturbances at Tiniroto are dynamic and a change of disturbance regime is suggested around the later disturbance episodes. This change is possibly due to climate increasing the fire frequency, but an alternative explanation is the presence of humans earlier than currently accepted. Forests and forest ecological studies in New Zealand are very dynamic, and forest management needs to improve to incorporate these dynamics.

Thesis (M.S.)--University of Tennessee, Knoxville, 2009. / Title from title page screen (viewed on Mar. 11, 2010). Thesis advisor: Sally P. Horn. Vita. Includes bibliographical references.

La région du lac Mégantic est probablement la première zone à s'être déglacée au Québec, ce qui lui confère un intérêt particulier. L'analyse pollinique et anthracologique des sédiments des trois lacs situés à ses abords, soit les lacs Clinton, Dubuc et des Joncs ont permis de reconstituer l'histoire locale et régionale de la végétation et des feux. La présence d'un gradient altitudinal a entrainé des décalages surtout dans l'instauration des premières phases forestières. La région s'est déglacée vers 13 500 ans AA, et une toundra s'y est installée. Le début de l'afforestation est marqué par l'arrivée du sapin baumier et de l'épinette noire. Par la multiplication de leurs populations, la forêt s'est fermée vers 10 000 ans AA pour constituer une forêt boréale qui fût alors perturbée par plusieurs épisodes de feux. Vers 8000 ans AA, les nouvelles conditions climatiques favorisent les espèces feuillues et instaurent une érablière à bouleau jaune et une diminution de la fréquence des feux. Les résultats obtenus permettent d'enrichir les connaissances paléophytogéographiques et anthracologiques du Québec. / The Lac Mégantic area is probably the first deglaciated in Quebec (13,500 cal. BP) which gives it a special interest. The pollen and charcoal analysis in sediments of three lakes located in its vicinity, Clinton, Dubuc and des Joncs Lakes, helped to reconstruct postglacial vegetation and fire, locally and regionally. The presence of an altitudinal gradient resulted in some delays in the introduction of various forest stages especially at the beginning. At start, tundra established in the region. The start of the afforestation is marked by the arrival of the balsam fir and black spruce. By multiplying their populations, the forest closed around 10,000 years cal. BP to build a boreal forest and was also disturbed by multiple fires. By 8,000 years cal. BP, new conditions favored deciduous species and created a sugar maple and yellow birch forest associated with lower fire frequencies. This study offers new perspectives in fire and forest reconstitutions by using proximal sites.

To study the ecology of organic-walled dinoflagellate cysts, the changes in species composition, diversity, and seasonal variations of cyst flux in the sediment trap deployed in the Strait of Georgia (BC, Canada) were examined. The cyst production rate varied from ~600 to 336,200 cysts m-2 day-1, with an average of 20,000 cysts m-2 day-1. Throughout the study period (March, 1996 - January, 1999), cyst assemblages were mostly dominated by cysts produced by heterotrophic dinoflagellates, such as Protoperidineaceae (Brigantedinium spp., Quinquequspis concreta, and cysts of Protoperidinium americanum). Cysts produced by heterotrophic dinoflagellates peaked in June each year, whereas cysts produced by autotrophic taxa were most abundant during August-September. The total annual dinoflagellate cyst flux was higher in 1996 than in 1997 and 1998, being enhanced by the bloom of Alexandrium spp. The warmer sea-surface temperature in 1998 had a positive effect on the production of both autotrophic and heterotrophic dinoflagellates, as inferred from the cyst fluxes.

This thesis presents a detailed late Tertiary and early Quaternary pollen record from two c. 40 m long sedimentary cores (the Patiki cores) from west Auckland. The cores consist of slightly to highly carbonaceous clays, with a thick sand incursion at mid-depth. The sediments below the sand incursion are aged through palynostratigraphy as mid-late Pliocene (Hautawan). The sediments above the sand incursion have numerous interbedded tephras, and are aged through a combination of Isothermal Plateau Fission Track dating, palaeomagnetism and orbital tuning to the marine oxygen isotope record as 1.0 – 1.4 Ma (MIS 28 - 45, Marahauan substage). The Tertiary pollen record portrays regional vegetation assemblages of extinct Nothofagus brassii-type species and modern-day podocarps, with local modern-day oligotrophic mire assemblages. A cool climatic phase is indicated by a period of dominance of an extinct member of the Proteaceae. However, the duration of this interval cannot be determined due to a lack of numerical age control for the record. The Quaternary pollen record consists of mostly extant pollen types. It shows multiple compositional shifts from Nothofagus-dominated to conifer-dominated regional vegetation, with local oligotrophic mire vegetation except for a fully aquatic phase at mid-depth (MIS 35). The primary axis score curve of a detrended correspondence analysis (DCA) of the pollen record was correlated to the marine isotope record, and shows that the Nothofagus-dominated intervals correspond to cool climate stages, while the conifer-dominated intervals correspond to warm stages. The strongest cool stage maximum is indicated at 12 - 13 m depth (MIS 34), where the vegetation consists of Fuscospora, Prumnopitys taxifolia and heath shrubs. The strongest warm stage maximum is indicated at c. 9 m depth (MIS 31) where the vegetation consists of Dacrydium forest. Astronomically forced climate change is an important driving force behind vegetation composition changes portrayed in the Quaternary pollen record. The majority of warm stage maxima inferred in the pollen record (conifer-dominated intervals) coincide with periods of maximum obliquity, and vice versa for inferred cool stage maxima (Nothofagus-dominated intervals). The modulating effect of eccentricity on precession is influential on the pollen record during MIS 31 and 34. The relationship between selected climate indicator taxa and calculated insolation values indicates that reduced seasonality in Auckland during warm climate stages favours Agathis, Dacrydium, Phyllocladus and Halocarpus, while increased seasonality during cool climate stages favours Nothofagus ‘fusca'-type, Nothofagus menziesii, and Prumnopitys taxifolia. In both situations the trees are probably responding to a combination of changes in mean global temperatures and seasonality, and reacting according to their own adaptive responses to astronomically driven climate change. The Quaternary pollen record contains plant mixtures that do not occur in New Zealand today, for example Agathis australis with Nothofagus menziesii, and Halocarpus bidwillii / biformis. The climate was probably cooler than it is in Auckland today, but never as cold as the last glacial maximum in Auckland when grasslands were present. Under more equable climatic conditions, with less extreme glacial and interglacial cycles, populations of comparably 'warm' and 'cool' climate taxa were probably able to shift throughout the region and mixed to a greater extent than is currently observed. The overall vegetation response to climate change (particularly above MIS 36) is analogous to that recorded in northern New Zealand in the late Pleistocene, and supports a negligible change in climatic preference of the main canopy species since the early Quaternary. The phytosociological idiosynchracies in the pollen record are not inconsistent with the known tolerance limits of the taxa involved, or with the individualistic nature of vegetation composition.

This thesis presents a detailed late Tertiary and early Quaternary pollen record from two c. 40 m long sedimentary cores (the Patiki cores) from west Auckland. The cores consist of slightly to highly carbonaceous clays, with a thick sand incursion at mid-depth. The sediments below the sand incursion are aged through palynostratigraphy as mid-late Pliocene (Hautawan). The sediments above the sand incursion have numerous interbedded tephras, and are aged through a combination of Isothermal Plateau Fission Track dating, palaeomagnetism and orbital tuning to the marine oxygen isotope record as 1.0 – 1.4 Ma (MIS 28 - 45, Marahauan substage). The Tertiary pollen record portrays regional vegetation assemblages of extinct Nothofagus brassii-type species and modern-day podocarps, with local modern-day oligotrophic mire assemblages. A cool climatic phase is indicated by a period of dominance of an extinct member of the Proteaceae. However, the duration of this interval cannot be determined due to a lack of numerical age control for the record. The Quaternary pollen record consists of mostly extant pollen types. It shows multiple compositional shifts from Nothofagus-dominated to conifer-dominated regional vegetation, with local oligotrophic mire vegetation except for a fully aquatic phase at mid-depth (MIS 35). The primary axis score curve of a detrended correspondence analysis (DCA) of the pollen record was correlated to the marine isotope record, and shows that the Nothofagus-dominated intervals correspond to cool climate stages, while the conifer-dominated intervals correspond to warm stages. The strongest cool stage maximum is indicated at 12 - 13 m depth (MIS 34), where the vegetation consists of Fuscospora, Prumnopitys taxifolia and heath shrubs. The strongest warm stage maximum is indicated at c. 9 m depth (MIS 31) where the vegetation consists of Dacrydium forest. Astronomically forced climate change is an important driving force behind vegetation composition changes portrayed in the Quaternary pollen record. The majority of warm stage maxima inferred in the pollen record (conifer-dominated intervals) coincide with periods of maximum obliquity, and vice versa for inferred cool stage maxima (Nothofagus-dominated intervals). The modulating effect of eccentricity on precession is influential on the pollen record during MIS 31 and 34. The relationship between selected climate indicator taxa and calculated insolation values indicates that reduced seasonality in Auckland during warm climate stages favours Agathis, Dacrydium, Phyllocladus and Halocarpus, while increased seasonality during cool climate stages favours Nothofagus ‘fusca'-type, Nothofagus menziesii, and Prumnopitys taxifolia. In both situations the trees are probably responding to a combination of changes in mean global temperatures and seasonality, and reacting according to their own adaptive responses to astronomically driven climate change. The Quaternary pollen record contains plant mixtures that do not occur in New Zealand today, for example Agathis australis with Nothofagus menziesii, and Halocarpus bidwillii / biformis. The climate was probably cooler than it is in Auckland today, but never as cold as the last glacial maximum in Auckland when grasslands were present. Under more equable climatic conditions, with less extreme glacial and interglacial cycles, populations of comparably 'warm' and 'cool' climate taxa were probably able to shift throughout the region and mixed to a greater extent than is currently observed. The overall vegetation response to climate change (particularly above MIS 36) is analogous to that recorded in northern New Zealand in the late Pleistocene, and supports a negligible change in climatic preference of the main canopy species since the early Quaternary. The phytosociological idiosynchracies in the pollen record are not inconsistent with the known tolerance limits of the taxa involved, or with the individualistic nature of vegetation composition.

This thesis presents a detailed late Tertiary and early Quaternary pollen record from two c. 40 m long sedimentary cores (the Patiki cores) from west Auckland. The cores consist of slightly to highly carbonaceous clays, with a thick sand incursion at mid-depth. The sediments below the sand incursion are aged through palynostratigraphy as mid-late Pliocene (Hautawan). The sediments above the sand incursion have numerous interbedded tephras, and are aged through a combination of Isothermal Plateau Fission Track dating, palaeomagnetism and orbital tuning to the marine oxygen isotope record as 1.0 – 1.4 Ma (MIS 28 - 45, Marahauan substage). The Tertiary pollen record portrays regional vegetation assemblages of extinct Nothofagus brassii-type species and modern-day podocarps, with local modern-day oligotrophic mire assemblages. A cool climatic phase is indicated by a period of dominance of an extinct member of the Proteaceae. However, the duration of this interval cannot be determined due to a lack of numerical age control for the record. The Quaternary pollen record consists of mostly extant pollen types. It shows multiple compositional shifts from Nothofagus-dominated to conifer-dominated regional vegetation, with local oligotrophic mire vegetation except for a fully aquatic phase at mid-depth (MIS 35). The primary axis score curve of a detrended correspondence analysis (DCA) of the pollen record was correlated to the marine isotope record, and shows that the Nothofagus-dominated intervals correspond to cool climate stages, while the conifer-dominated intervals correspond to warm stages. The strongest cool stage maximum is indicated at 12 - 13 m depth (MIS 34), where the vegetation consists of Fuscospora, Prumnopitys taxifolia and heath shrubs. The strongest warm stage maximum is indicated at c. 9 m depth (MIS 31) where the vegetation consists of Dacrydium forest. Astronomically forced climate change is an important driving force behind vegetation composition changes portrayed in the Quaternary pollen record. The majority of warm stage maxima inferred in the pollen record (conifer-dominated intervals) coincide with periods of maximum obliquity, and vice versa for inferred cool stage maxima (Nothofagus-dominated intervals). The modulating effect of eccentricity on precession is influential on the pollen record during MIS 31 and 34. The relationship between selected climate indicator taxa and calculated insolation values indicates that reduced seasonality in Auckland during warm climate stages favours Agathis, Dacrydium, Phyllocladus and Halocarpus, while increased seasonality during cool climate stages favours Nothofagus ‘fusca'-type, Nothofagus menziesii, and Prumnopitys taxifolia. In both situations the trees are probably responding to a combination of changes in mean global temperatures and seasonality, and reacting according to their own adaptive responses to astronomically driven climate change. The Quaternary pollen record contains plant mixtures that do not occur in New Zealand today, for example Agathis australis with Nothofagus menziesii, and Halocarpus bidwillii / biformis. The climate was probably cooler than it is in Auckland today, but never as cold as the last glacial maximum in Auckland when grasslands were present. Under more equable climatic conditions, with less extreme glacial and interglacial cycles, populations of comparably 'warm' and 'cool' climate taxa were probably able to shift throughout the region and mixed to a greater extent than is currently observed. The overall vegetation response to climate change (particularly above MIS 36) is analogous to that recorded in northern New Zealand in the late Pleistocene, and supports a negligible change in climatic preference of the main canopy species since the early Quaternary. The phytosociological idiosynchracies in the pollen record are not inconsistent with the known tolerance limits of the taxa involved, or with the individualistic nature of vegetation composition.