This dissertation presents results from a multi-year interdisciplinary study of the Late Quaternary geomorphic history of northwest Calvert Island, British Columbia, Canada. There is a considerable knowledge gap in the region pertaining to Cordilleran ice cover and extent as well as landscape response to a uniquely stable relative sea-level history. The objective of this study was to reconstruct this regional landscape response to deglaciation including post-LGM ice cover and extent, relative sea-level changes, coastal landform development, and climate and ecological variance. Methods used to inform this reconstruction included airborne lidar, aerial photography interpretation, sedimentary stratigraphy and detailed sedimentology of samples from shovel pits and lake cores, surficial geology and geomorphic mapping, palaeoecological examinations, and the development of a geochronology using radiocarbon and optical dating. To assist with landscape reconstruction, a new method was developed and used to differentiate littoral and aeolian sands in sediment samples that range in age from Mid to Late Holocene by using modern reference samples. The method utilized a standard optical microscope paired with freely available software (ImageJ) to characterize grain shape parameters. The method was tested on nearly 6,000 sand grains from samples of known and hypothesized depositional settings and was able to correctly identify the depositional setting for 76% of the samples. After testing, the method was used to differentiate littoral and aeolian sands in a number of shovel pit, exposure, and core sediment samples to give context to stratigraphic and geomorphic interpretations. A short-lived Late Pleistocene re-advance of Cordilleran ice occurred in the study area, with radiocarbon ages indicating ice advanced to, and then retreated from, the western edge of Calvert Island between 14.2 and 13.8 ka cal BP, respectively. Sedimentological and palaeoecological information that suggests a cold climate and advancing/retreating glacier as well as lidar remote sensing and field-based geomorphic mapping of moraines in the region provide evidence of the re-advance. After ice retreated from the area, a broad suite of geomorphic landforms developed, including flood plains, iv aeolian dunes, beaches, spits, marshes, and tombolos. Coastal reworking was extensive, with progradation rates greater than 1 m a-1 occurring in some locations during the Late Holocene. These data provide the first evidence of a re-advance of the retreating ice sheet margin on the central coast of British Columbia, contribute an important methodology to advance Quaternary reconstructions, and give a unique account of the geomorphic development of a Pacific Northwest coastline that experienced little relative sea-level change over the Late Pleistocene and Holocene. Results help fill a spatial and temporal gap in the landscape history of British Columbia and have implications for climate and sea-level reconstructions, early human migration patterns, and the palaeoenvironment of an understudied area of the Pacific Northwest coast of North America. / Graduate / 0368 / 0372 / 0426 / jeamer7@gmail.com

Taxonomic position of the brachiopod genus Euorthisina HAVLÍ EK 1950 from the Ordovician of the Prague Basin (Czech republic) was subjected to wide discussions and disputes in the past. The genus was first classified within the superfamily Syntrophiiacea (order Pentamerida). Later, a separate family Euorthisinidae by Havlí ek (1977) was defined. At present, the family is assigned to the order Orthida and includes genera Euorthisina HAVLÍ EK, 1950, Lesserorthis BENEDETTO, 2007, Notorthisina HAVLÍ EK & BRANISA, 1980 and Protorthisina BENEDETTO, 2007. In this thesis, a revision of genus Euorthisina HAVLÍ EK 1950 with emphasis on taxonomic classification, palaeoecology and palaeogeographic occurrence of species E. moesta and E. minor described from the Ordovician of the Prague Basin has been made. Klí ová slova: Euorthisina, brachiopoda, Ordovician, Prague Basin, Czech republic.

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Submitted by Maicon Juliano Schmidt (maicons) on 2015-07-03T17:37:20Z No. of bitstreams: 1 Hugo Schmidt Neto.pdf: 3763887 bytes, checksum: 8a837a24fd2ae953f70fb46e18ca9e16 (MD5) / Made available in DSpace on 2015-07-03T17:37:20Z (GMT). No. of bitstreams: 1 Hugo Schmidt Neto.pdf: 3763887 bytes, checksum: 8a837a24fd2ae953f70fb46e18ca9e16 (MD5) Previous issue date: 2013-01-31 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / CNPQ – Conselho Nacional de Desenvolvimento Científico e Tecnológico / No município de Taió, Santa Catarina, o Membro Paraguaçu apresenta uma expressiva fauna de invertebrados marinhos contidos em camadas de areias muito finas, denominadas informalmente de Camadas Taió. Sua assembleia se desenvolveu em um período pós-glacial e foi influenciada pelas condições do degelo do final do Grupo Itararé. Assim o presente trabalho teve como objetivo realizar a análise paleoecológica destes depósitos a fim de elucidar o impacto do aporte de águas de degelo no mar Taió. Para tanto foi realizado um estudo tafonômico dos repositórios das instituições científicas do Rio Grande do Sul, Santa Catarina e São Paulo, tal como dos registros fósseis nos afloramentos (in loco). Os perfis das sucessões sedimentares, das áreas fossilíferas foram correlacionados a partir da comparação de suas fácies. As assinaturas tafonômicas mostram sinais de pouco transporte e rápido soterramento, com pouca colonização dos bioclastos por organismos espongiários. O padrão de ocorrência da biofábrica Rosselia isp. indica a ação de eventos de tempestade e alta frequência sedimentar. Uma maior quantidade de restos vegetais na base da sucessão indica uma maior proximidade da costa, enquanto formas diminutas de moluscos e equinodermos, ocorrentes nas fácies que sugerem uma zona de shoreface, indicam águas de baixas temperaturas. Os dados alcançados neste trabalho indicam que as águas do degelo do final do Carbonífero continuaram impactando a fauna marinha do Mar Paraguaçu pela flutuação de sua salinidade e de seu condicionamento a baixas temperaturas. / At the Taio city, Santa Catarina State, the Paraguassu Member presents a significant marine invertebrate fauna contained in layers of very fine sand, informally designed Layers Taio. Its congregation has developed into a post-glacial conditions was influenced by the melting of the final Itararé Group. Thus, the present study aimed to conduct paleoecological analysis of these deposits in order to elucidate the impact of the inflow of water from melting sea Taio. Therefore, went make a taphonomic study of repositories of scientific institutions of Rio Grande do Sul, Santa Catarina and São Paulo states, as the fossil record in outcrops (in situ). The profiles of sedimentary successions, fossiliferous areas were correlated from the comparison of their facies. The taphonomic signatures show little signs of rapid transportation and burial, with little colonization by organisms of bioclasts sponges. The pattern of occurrence of biofabric Rosselia isp. indicates the action of storm events and high-frequency sediment. A larger quantity of plant debris on the basis of the sequence indicates closer proximity to the coast, while forms tiny molluscs and echinoderms, suggesting facies that occur in a zone of shoreface indicate low water temperatures. The data obtained in this work indicate that the waters of the melting of the end of the Carboniferous continued impacting the marine fauna of the Sea Paraguaçu by floating its salinity and his conditioning at low temperatures.

<p>This thesis presents palaeoenvironmental data from equatorial Africa covering two important time intervals; i) the warming period forming the Pleistocene/Holocene transition and ii) the last millennium. The Empakaai Crater, in northern Tanzania contains a lake from where sediment cores, spanning two time-slices 14.8-9.3 ka and 800-2000 AD, have been studied. Palaeoecological and palaeohydrological reconstruction is based on a multitude of proxies from the sediments, representing both catchment environment and the lakes aquatic ecosystem response. Between 14.8 and 10 ka the catchment vegetation and lake hydrology responded to both regional climate changes and local environment, but with different amplitude and frequency, reflecting temporal and spatial lags between the two systems. However, at c 10 ka both lake conditions and catchment vegetation showed drastic changes towards drier conditions. The record covering the last millennium reveals environmental changes related to climate and human activities. The catchment’s vegetation was affected by frequent fires, most probably human induced, while near shore vegetation responded to lake level fluctuation associated with rainfall variability. About 15 km from Empakaai Crater is an extensive abandoned irrigation system, the Engaruka complex, which was in active use between c 1400 AD and 1840 AD. By comparing a number of social and environmental factors potentially influencing the societal development at Engaruka it is shown that wet climate conditions have had positive effects on the societal development but also that dry climate conditions were not always disastrous to the society. The resemblance of the pollen taxa present is strong between the two time slices and pollen representing catchment conditions respond in similar manner in both records. The lake conditions are however very different between the two periods Thus the lake responds to both long and short term changes of variable amplitude, while the catchment vegetation seems to responds to high amplitude, low frequency changes.</p>

This thesis presents palaeoenvironmental data from equatorial Africa covering two important time intervals; i) the warming period forming the Pleistocene/Holocene transition and ii) the last millennium. The Empakaai Crater, in northern Tanzania contains a lake from where sediment cores, spanning two time-slices 14.8-9.3 ka and 800-2000 AD, have been studied. Palaeoecological and palaeohydrological reconstruction is based on a multitude of proxies from the sediments, representing both catchment environment and the lakes aquatic ecosystem response. Between 14.8 and 10 ka the catchment vegetation and lake hydrology responded to both regional climate changes and local environment, but with different amplitude and frequency, reflecting temporal and spatial lags between the two systems. However, at c 10 ka both lake conditions and catchment vegetation showed drastic changes towards drier conditions. The record covering the last millennium reveals environmental changes related to climate and human activities. The catchment’s vegetation was affected by frequent fires, most probably human induced, while near shore vegetation responded to lake level fluctuation associated with rainfall variability. About 15 km from Empakaai Crater is an extensive abandoned irrigation system, the Engaruka complex, which was in active use between c 1400 AD and 1840 AD. By comparing a number of social and environmental factors potentially influencing the societal development at Engaruka it is shown that wet climate conditions have had positive effects on the societal development but also that dry climate conditions were not always disastrous to the society. The resemblance of the pollen taxa present is strong between the two time slices and pollen representing catchment conditions respond in similar manner in both records. The lake conditions are however very different between the two periods Thus the lake responds to both long and short term changes of variable amplitude, while the catchment vegetation seems to responds to high amplitude, low frequency changes.

A lack of well-distributed, high-resolution records of Late Quaternary Asian palaeomonsoon variability remains an outstanding issue for palaeoclimatologists, and is especially marked in remote regions such as the mountains of southwestern China (Wang et al., 2005). Characterising the nature, timing and magnitude of climate variability in southwestern China is essential for understanding the regional climate as a whole, and the potential social, economic and environmental impacts that may result from Asian monsoon system changes. The NERC-funded research presented in this thesis focuses on a high altitude lake sediment record obtained from Lake Shudu, Yunnan Province, China. The lake is located on the southeastern edge of the Tibetan Plateau. The primary aims of this research were to identify and examine key environmental and climatic shifts which occurred in southwestern China during the Late Pleistocene (Dali) - Early Holocene Period; to examine the possible drivers of these changes; and to compare the findings with other regional proxy records in order to better understand climate dynamics in southwestern China. These aims were chosen in order to test the hypothesis that Late Quaternary millennial to centennial scale climatic and environmental changes in southwestern China were driven by changes in solar insolation and / or glacial climate boundary conditions, characterised by stepwise increases in palaeomonsoon intensity. AMS 14C radiocarbon dates obtained from bulk sediment samples and pollen concentrations indicated that the seven metre core (06SD) that forms the focus of this research spans the last c. 22.6 ka cal. yr BP, making it one of the longest high-resolution Late Quaternary records available for southwestern China. 06SD was examined using a multi-proxy approach incorporating physical, organic and palaeoecological analyses. The record captures the shift from colder, drier Pleistocene (Dali) conditions to warmer, wetter Holocene conditions and is punctuated by two events. The first event, centred at c. 17.3 ka cal. yr BP, possibly represents a phase of warmer and / or wetter conditions in response to rising solar insolation during the deglacial period. The second event, commencing at c. 11.7 ka cal. yr BP, possibly denotes the Pleistocene - Holocene Boundary. Overall, the findings of this research support the view that during the Late Pleistocene, Asian summer monsoon strengthening was non-linear and driven by changes in glacial dynamics and / or solar insolation.

The overall aim of this thesis was to explore the impact of environmental changes (relative sea level increase and climate) on coastal communities and to investigate how these environmental factors controlled subsistence economies through the Holocene. The hypothesis tested was that relative sea level rise is a key factor influencing location and subsistence strategies of coastal communities throughout the Holocene and that, due to environmental conditions, these changes will be more evident in islands. The Isles of Scilly, located 27 miles off the south west coast of England, provide a good case study for the response of communities to marine inundations and environmental changes. This project aimed also to obtain a high resolution record of vegetation and storminess during the last 3000 years in Scilly, with a robust chronological setting, and also to offer an accurate shape of the coastline of Scilly since the early Holocene. Three terrestrial pollen stratigraphic sequences from the Isles of Scilly were obtained, covering the past 3000 years, from the two main wetland areas of Scilly (one in Higher Moors and two in Lower Moors) with the potential to reveal changing patterns of vegetation reflecting intensity and type of land use. Detailed palaeoenvironmental interpretation has been provided by high resolution pollen analysis. These pollen diagrams suggest that the landscape of Scilly has been an open landscape, heavily managed for both pastoral and arable agriculture since the Bronze Age. There is evidence that the climate during the Holocene period was highly varied. The occurrence of blown sand in the sample cores has been used as an indicator of past storm intensity, by high resolution particle size analysis and Loss-On-Ignition. The three cores show dissimilarities in the storminess indicator during the same periods. It is argued that this reflects that sand deposition and transport is highly site specific and controlled by topography, sediment availability, wind directions and vegetation cover. An important part of this thesis was to determine the impact of relative sea level rise in Scilly and the extent of the islands over time. A new sea level curve for Scilly has been generated through GIA (Glacial Isostatic Adjustments) using the Bradley et al (2011) method. Palaeogeography maps were produced applying the sea level curve to a new combined bathymetric and topographic model for Scilly. Scilly separated from the mainland around 11500 cal BP, and the islands obtained their modern configuration around 4000 cal BP. The palaeogeography, palaeoecological and the archaeological records of Scilly show that changes in the coastal configuration and storminess had little apparent influence on society from the 1st millennium AD into medieval times. Both, the archaeological and palaeoenvironmental record, have demonstrated that Scillonian societies had a strong resilience and were able to adapt to environmental changes by diversifying their economic strategies and taking advantage of the new conditions, such as new coastal margins. This adaptability was strong until the development of more complex societies and major land reduction conditions that probably led to a tipping point in resilience. There is no apparent discontinuity in land-use on Scilly during the last 3,000 years, although there have been important social and environmental changes.

Los Andes ecuatorianos albergan ecosistemas con la más alta biodiversidad sobre la tierra. Información preliminar sobre la dinámica de los ecosistemas en el pasado es necesaria para entender, conservar y manejar los ecosistemas y su biodiversidad. Tres muestras de sedimentos fueron datadas, Rabadilla de Vaca (RV) a 3244 m de altura y Valle Pequeño (VP) a 3200 m de altura, ambas en la parte central del Parque Nacional Podocarpus (PNP), y Lagunas Natosas Bosque (LNB) a 3495 m de altura, al sur del PNP al sur del Ecuador en la región llamada Depresión Andina. Estas muestras fueron estudiadas con base en análisis de polen, esporas y partículas de carbón. Los resultados revelan cambios en la vegetación en la zona de LNB durante los últimos 16,000 años, y en RVM y VP desde hace 2100 años. Durante el Plestoceno tardío (15,930 – 11,660 cal yr BP), la vegetación de páramo dominó el área y la presencia de Plantago rigida sugiere condiciones ambientales frías y húmedas en el área de LNB. La población de P. rigida disminuyó drásticamente durante el último período glacial y especialmente durante el “Younger Dryas”, que es un corto período frío (hace 12,800 a 11,500 años), y el límite superior del bosque (UFL) muy probablemente fue mas bajo que en la actualidad. Entre 11,660 – 4280 cal yr BP, ocurrió una marcada reducción de cobertura de páramo, acompañada por una expansión de la vegetación de subpáramo (arbusto enano leñoso). En la región de LNB, al sur del PNP, se evidención un cambio altitudinal hacia arriba del UFL. En este sitio se evidencia por primera vez la presencia de grandes extensiones de Polylepis en la región de la Depresión Andina. Alrededro de 4200 cal yr BP el regreso a condiciones climáticas frías y húmedas favoreció la expansión de los páramos. El Holoceno tardío hasta el presente se caracteriza por la contínua fluctuación entre vegetación de páramo y subpáramo. Sin embargo, alrededor de los 1200 cal yr BP, vegetación de subpáramo (arbustos enanos) fueron precuentes, lo que sugiere un incremento moderado en temperatura y humedad. En el área de RVM desde los 2100 hasta los 1720 cal yr BP, la dominancia de subpáramo sugiere condiciones climáticas más húmedas y cálidas. En el área de LNB después de los 500 cal yr BP, el incremento de vegetación de páramo indica condiciones más húmedas. Esto también se registró en la zona de RVM y VP desde 800 a 310 cal yr BP, donde la vegetación de páramo se expandió ampliamente y redujo la posibilidad de crecimiento de bosque. Inlfuenciada por condiciones más húmedas y fuegos (incendios) frecuentes, en el área de LNB, Polylepis estuvo casi ausente durante el Holoceno tardío. Aunque, restos de partículas de carbón indican la presencia humana desde hace más de 4000 años. La máxima concentración de partículas de carbón indican alta frecuencia de fuegos desde 1800 hasta 1600 cal yr BP y desde 600 a 400 cal yr BP. Comparando la vegetación y los regsitros de carbón entre los tres sitios, es evidente que el fuego favoreció la expansión de vegetación de páramo en detrimento de la vegetación de subpáramo y bosque montano alto (UMF). El fuego probablemente tuvo un rol importante en el control de los cambios del límite del bosque durante el Holoceno tardío. Sin embargo, es difícil establecer si cambios en las condiciones del clima también tuvieron un rol importante durante este período. Los fuegos se presentaron a distintos momentos entre los diferentes sitios, esto sugiere que existió influencia antropogénica. Es posible inferir cambios a nivel regional ocasionados por la variabilidad de clima; sin embargo, condiciones locales como temperatura, precipitación, vientos, radiación solar y geomorfología, también tienen un impacto fuerte en los patrones de la vegetación, los mismos que pueden determinar la estructura, heterogeneidad y distribución de los ecosistemas.

In contrast to the wealth of palaeoenvironmental research stemming from the eastern Afromontane archipelago, the southern Afromontane component, which comprises largely of the Drakensberg, remains understudied. The Drakensberg constitute an area of significant biodiversity, cultural and economic importance. Suitable sites for palaeoenvironmental research are rare in South Africa due to general arid climatic conditions over much of the country. The KwaZulu-Natal Drakensberg offers a unique opportunity for palaeoenvironmental research through its increased rainfall and higher altitudes, which enable the development of wetlands that have the potential for polliniferous accumulation to occur. Catchment Six in Cathedral Peak is one such wetland that has provided an opportunity to research palaeoenvironmental conditions of the southern Afromontane archipelago component. A 371 cm sediment core was extracted from a subalpine wetland in Catchment Six and analysed using multiple proxies including; pollen, charcoal and geochemistry (carbon and nitrogen stable isotopes). A chronological framework for the core was established based on accelerated mass spectrometry radiocarbon dating of eight bulk sediment samples. A basal date of 15,100 ± 445 cal yr BP was determined at a depth of 298 cm. Poor pollen preservation of the basal portion of the core limited palaeoenvironmental inference for the late Pleistocene section of the record. The multiproxy record provides high chronological resolution for the early to late Holocene. Multi-proxy data indicate that the Holocene period in the Drakensberg was characterised by variable climatic conditions. Charcoal data indicate periods of increased regional fires in the last ca. 400 cal yr BP. Palaeoenvironmental inferences from the Catchment Six record are broadly in agreement with regional climatic indications based on existing literature. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.