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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.
11

Transition to farming and human impact on the Slovenian landscape

Andric, Maja January 2001 (has links)
No description available.
12

Late Pleistocene sea-level change in the Celtic Sea : radiocarbon dated macrofauna as palaeo-water-depth indicators

Furze, Mark Fernley Alexander January 2001 (has links)
No description available.
13

Archaeological and palaeoecological implications of charcoal assemblages dated to the Holocene from Great Zimbabwe and its hinterland

Chikumbirike, Joseph 21 July 2014 (has links)
In most of Africa archaeological charcoal samples are often used to establish chronology through radiocarbon dating, but are rarely used to address why people may have selected specific wood taxa for particular purposes. This thesis is an enquiry into the palaeo-ethnobotanical and palaeoecological implications of charcoal assemblages dated to the late Holocene from the Great Zimbabwe and Chigaramboni sites, Zimbabwe. The research provided a more detailed picture of socio-economic utilization of wood, such as the use of woods for iron smelting, construction and domestic hearths. Previous excavations at Great Zimbabwe and Chigaramboni have produced large samples of charcoal at specific activity sites and at a few different depths thus giving a minor perspective of time. There was a wider selection of wood at Great Zimbabwe as compared to Chigaramboni. Charcoal samples analyzed in this thesis are a product of purposeful human action and they represent a subsample of the local vegetation and related human activities contemporaneous with the period of sites’ use. A substantial effort has been invested in the development of a modern vegetation reference collection database. This will go a long way in assisting future researchers in the region and is an extremely valuable and essential primary contribution to the development of wood charcoal studies in the region. Thirty different tree species were burnt at Great Zimbabwe and indicate the multipurpose nature of the settlement. In contrast only 14 species were exploited at Chigaramboni which is an iron and metallurgical processing site. The latter fuel woods were also used at Great Zimbabwe. Based on the cracks and fissures in the charcoal it is postulated that the firewood used in metallurgy were collected whilst they were wet. Since Spirostachys africana and Colophospermum mopane do not occur in the area today it is suggested that there was long distance movement of wood, particularly those with excellent construction qualities. It is quite possible that the inhabitants of Great Zimbabwe, or their trading partners, opted to travel long distances in order to collect those particular logs. The fuel woods used at the two sites occur in the region today so it is likely that the Miombo woodlands of Great Zimbabwe and Chigaramboni have not changed notably from the time of occupation by their original inhabitants to date. Based on the mesophytic species identified, such as Acacia robusta, Acacia sieberiana, Acacia xanthophloea, Acacia polyacantha, Acacia burkei, Faurea saligna, Schotia brachypetala, Kigelia africana and Parinari curatellifolia, it is concluded that the inhabitants of ancient Great Zimbabwe and Chigaramboni archaeo-metallurgical site experienced a mesic environment. New excavations of different occupation levels would be required to determine vegetation and climate fluctuations during the past but at present there is a moratorium on such disturbance of the historical sites.
14

Styles of coastal evolution in response to Holocene changes in sea level and sediment supply

Hein, Christopher January 2012 (has links)
Thesis (Ph.D.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / This study employs a suite of geophysical, sedimentological, and chronostratigraphic tools to investigate the complex interactions among changes in sea level, climate, and sedimentation processes that have driven Holocene coastal evolution. These interrelationships were explored in investigations of three coastal sites with diverse sea-level and sedimentation histories: the Egyptian Red Sea (Wadi Gawasis), southern Brazil (Pinheira) and the Western Gulf of Maine (Plum Island). This study demonstrates the need to quantify the integrated impacts of spatially-diverse changes in global (sea level), regional (climate, sea level), and local (sedimentation) factors if we are to predict large-scale coastal evolution in response to the ongoing acceleration in sea-level rise. The mid-Holocene in both the Red Sea and southern Brazil was characterized by higher-than-present stands of sea level. Sedimentological, malachological, foraminiferal, and rheological studies at Wadi Gawasis reveal that this resulted in the formation of a shallow bay that reached its maximum extent prior to a 1.5-m highstand at 5 ka, demonstrating a dominance of sedimentation processes despite contrary sea-level change. Early bay closure was driven by sediment inputs enhanced by a wetter climate. Slowly falling sea level and coincidental climatic aridization allowed for the establishment of an Egyptian harbor 4 ka, followed by late-stage progradation dominated by sea-level fall. In southern Brazil, an abundant sediment supply and sea-level fall following the mid-Holocene highstand were responsible for the development of the 5-km wide Pinheira strandplain, composed of regular beach and dune ridges. Identification of anomalous barrier, lagoonal, and tidal fill deposits within this plain demonstrates the complex nature of the sedimentological response to a small-scale change in the rate of sea-level fall. By contrast, Plum Island formed in a regime of rapid sea-level rise that reworked shallow shelf and fluvial deposits. Geophysical and sedimentological studies reveal a complex barrier formation (aggradation, spit accretion and progradation), including evidence for inlet migration and closure. Time-transgressive backstripping of backbarrier facies shows that bay sedimentation in a regime of slowly rising sea level reduced tidal-prism and produced inlet closure. This is first study to demonstrate that the direct impact of backbarrier processes influencing barrier island development. / 2031-01-02
15

Holocene environmental and hydrologic change in Cambodia : examples from Tonle Sap Lake and Angkor

Day, Mary Beth January 2014 (has links)
No description available.
16

ADAPTATIONAL FLEXIBILITY AND PROCESSES OF EMERGING COMPLEXITY: EARLY TO MID-HOLOCENE FORAGERS IN THE LOWER JEQUETEPEQUE VALLEY, NORTHERN PERU

Stackelbeck, Kary L. 01 January 2008 (has links)
Early complex societies developed in the Central Andes as a result of in situ processes of culture change. However, the developments commonly associated with complex societiespermanent village settlement, monumental architecture, intensive agriculture, and institutionalized stratificationwere neither uniformly nor simultaneously adopted. Rather, they appear to have been the result of different trajectories that initially were tied to changes among populations in certain circumscribed areasoften within individual valley systems. This dissertation explores the cultural and historical contexts of emerging complexity in one such areathe lower Jequetepeque Valley in northern Peru. This area encompasses several quebrada drainages and associated landforms along the lower, western flanks of the Andes, which were the focus of intensive Preceramic occupation (~11,000-4000 14C BP). The Preceramic Period correlates with the transition from the Terminal Pleistocene to the mid-Holocene, which involved changes in the local environment from cooler, wetter conditions to warmer, drier conditions that approximate the modern arid setting. Despite these deteriorating conditions, transitional late Early through Middle Preceramic (LE/M) populations (~9000-4500 14C BP) continued to occupy the project areawith some adjustments compared to their Paijanense predecessors (~11,000-9000 14C BP)based on survey and excavation data from 138 sites. These data consist of faunal remains, lithic tools and debris, hearth features, land snail middens, limited paleobotanical remains, and remnants of simple domestic structures and two possible rudimentary canals. Analyses of these data indicate that LE/M populations had intensified the localization of their settlement and subsistence patterns, and transformed their use and materialization of certain spaces to which they had become tethered. Taken collectively with evidence of Early through Middle Preceramic occupation in the nearby Zana and Chicama Valleys, the regional patterns observed among these three drainages indicate that a broad-spectrum diet, territoriality, ritualistic activities, and the separation of public and private spheres of activity preceded the adoption of intensive agriculture, socio-economic stratification, and the construction of large-scale monumental architecture, among other, more recognizable markers of cultural complexity. Further, these patterns indicate that Preceramic populations in this region actively negotiated changes in their local environment and social landscape by employing strategies of adaptational flexibility.
17

MID-HOLOCENE EMERGENT COMPLEXITY AND LANDSCAPE TRANSFORMATION: THE SOCIAL CONSTRUCTION OF EARLY FORMATIVE COMMUNITIES IN URUGUAY, LA PLATA BASIN

Iriarte, José 01 January 2003 (has links)
This dissertation is a multidisciplinary study combining both archaeological andpaleoecological data to examine the rise of early Formative societies in Uruguay, La Plata Basin.It is contextualized within broader anthropological concerns related to the emergence of culturalcomplexity, the significance of ritual and public architecture in intermediate-level societies, andthe role of human-environment interactions during the mid-Holocene. This investigationgenerated the first Late Quaternary paleoclimatic record, based on pollen and phytolith analyses,documenting that the mid-Holocene (ca. 6,620 to ca. 4,040 bp) was a period of environmentalflux and increased aridity. It describes the occupational history of the Los Ajos site from thecreation of a household-based community integrating a centralized communal space during thePreceramic Mound Component (ca. 4,120 – 3,000- 2,500 bp) to the Ceramic Mound Component(ca. 3,000 2,500 bp to the Contact Period), where Los Ajos acquired a strong public ritualcharacter through the formatilization and spatial segregation of its mounded architecture. Duringthe Ceramic Mound Period, the site exhibited both internal stratification (inner versus outerprecincts) and dual asymmetrical architecture in its central sector, which suggest the emergenceof incipient social differentiation. This study also marks the earliest occurrence of at least twodomesticated crops in the region: corn (Zea mays) and squash (Cucurbita spp.), showing that theearly Formative societies adopted a mixed economy shortly after 4,120 bp. Collectively, theseresults challenge the long-standing view that the La Plata Basin was a marginal area byevidencing an early and idiosyncratic emergence of social complexity never before registered inthis region of South America.
18

Dune behavior in a multidirectional wind regime : White Sands Dune Field, New Mexico

Pederson, Anine Oehlenschlaeger 27 October 2014 (has links)
As with most dune fields, the White Sands Dune Field in New Mexico forms in a wind regime that is not unimodal. In this study, dune behavior at White Sands was documented from a time series of five lidar-derived digital elevation models (DEM) and compared to a record of wind direction and speed during the same period. For the study period of June 2007 - June 2010, 244 sand-transporting wind events occurred and define a dominant wind mode from the SW and lesser modes from the NNW and SSE. Based upon difference maps and tracing of dune brinklines, overall dune behavior consists of migration to the NE, but with along-crest migration of dune sinuosity to the SE. Permutations of the DEMs allow matching specific dune behavior with wind modes. The SW winds are transverse to dune orientations and cause most forward migration. The NNW winds cause along-crest migration of dune sinuosity and low stoss bedforms, as well as SE migration of NE-trending dune terminations. The SSE winds cause ephemeral dune deformation, especially crestal slipface reversals. Dune deformation occurs because of unequal deposition along the lee face as a function of the incidence angle formed between the wind and the local brinkline orientation. Incidence-angle control on dune deformation and types of lee-face surface processes allows for an idealized model for White Sands dunes. The dunes behave as complex systems in which each wind event deforms the dune shape, this new shape then serves as the configuration for the next wind event. / text
19

Human-environment interactions during the Mid-Holocene in Cumbria

Grosvenor, Mark James January 2014 (has links)
The influence of anthropogenic activity on the natural environment is constantly changing. A series of major developments in human culture have resulted in a shifting nature of impact. Separating change attributable to humans and the change resulting from natural forcing is complex. This study investigates the degree of human impact during the onset of agriculture when humans were shifting from a hunter-gatherer lifestyle to herding livestock and the cultivation of plants. This cultural development is known as the Mesolithic-Neolithic Transition within Europe. In particular, this project focuses on the nature of environmental change in Cumbria in the British Isles during the mid-Holocene. This region exhibits strong contrasts in landscape from coastal lowlands to mountainous uplands. Cumbria also has a rich record of archaeological sites and environmental reconstructions, but existing datasets have not allowed for detailed comparisons of the different landscapes. Two contrasting sites (one upland, one lowland) were investigated to produce a high-resolution environmental reconstruction including: vegetation change, burning patterns, catchment erosion and climatic changes. A radiocarbon chronology was produced for each site investigated. This was used to re-address the archaeological record and in particular, determine the details of the impact of humans on the landscape. Key differences are highlighted in the nature of human impact during the late-Mesolithic and early-Neolithic in contrasting landscapes with different types of land-use. There is an estimated temporal offset of around 200 years between similar events occurring in lowland and upland landscapes. Climatic variability indicates only small fluctuations and is unlikely to account for the extent of vegetation modification on its own. It is clear Neolithic activity is far more intensive than Mesolithic activity, but importantly the scale of impact in the upland landscape is far more extensive than the archaeological evidence would suggest. Furthermore, the upland landscape appears to recover relatively quickly after clearance events, whilst in the lowland environment, the open vegetation landscape remains far more dominant.
20

Reconstructions of Late Holocene storminess in Europe and the role of the North Atlantic Oscillation

Orme, Lisa Claire January 2014 (has links)
Winter storms can have devastating social and economic impacts in Europe. The severity of storms and the region they influence (southern or northern Europe) is related to the index of the North Atlantic Oscillation (NAO). However recent findings indicate that over the last millennium the relationship between the NAO and storminess varied and the forcings over centennial timescales are debated. Therefore in this research storminess has been reconstructed from NAO-sensitive regions of southern Europe (Galicia, Spain) and northern Europe (Outer Hebrides, Scotland), to investigate the Late Holocene NAO-storminess relationship and the causes of observed variability. Reconstructions were based on measurements of aeolian sand deposits within ombrotrophic peat bogs and a lake sedimentary archive from the Hebrides. The elemental composition of the lake sediments were analysed (using ITRAX XRF core scanning) to identify aeolian/in-washed sediment resulting from storms, as confirmed by correlations with instrumental data. As this is a relatively new technique there was a methodological focus on assessing its applicability for storm reconstructions and the maximum resolution achievable. It is concluded the reconstruction had a 10-year resolution (equivalent to 2-5 mm sampling resolution). The peat bog reconstructions span 4000 cal yr BP to present and indicate that there was a Late Holocene northward storm track shift. The results suggest that storminess was high in Galicia between 4000-1800 cal yr BP, after which it decreased and then gradually increased in the Outer Hebrides after 1500 cal yr BP. Comparison with an NAO reconstruction supports a consistent NAO-storm relationship through the Late Holocene. Orbital forcing is suggested as causing a steepening of the latitudinal temperature gradient and increasingly zonal circulation. Superimposed on this trend are centennial variations, which spectral analysis and visual comparisons suggest are primarily the result of solar minima (suggested as causing a weakened latitudinal temperature gradient and meridional circulation patterns), with some additional forcing from volcanic and oceanic changes. Therefore there has been a consistent storm-NAO relationship through the Late Holocene; however there appear to have been millennial and centennial shifts as the result of hemispheric circulation reorganisations.

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