43 resultados para Southeast Asia -- Description and travel


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The long-term climatic and environmental history of Southeast Asia, and of Thailand in particular, is still fragmentary. Here we present a new 14C-dated, multi-proxy sediment record (TOC, C/N, CNS isotopes, Si, Zr, K, Ti, Rb, Ca elemental data, biogenic silica) for Lake Kumphawapi, the second largest natural lake in northeast Thailand. The data set provides a reconstruction of changes in lake status, groundwater fluctuations, and catchment run-off during the Holocene. A comparison of multiple sediment sequences and their proxies suggests that the summer monsoon was stronger between c. 9800 and 7000 cal yr BP. Lake status and water level changes around 7000 cal yr BP signify a shift to lower effective moisture. By c. 6500 cal yr BP parts of the lake had been transformed into a peatland, while areas of shallow water still occupied the deeper part of the basin until c. 5400–5200 cal yr BP. The driest interval in Kumphawapi's history occurred between c. 5200 and 3200 cal yr BP, when peat extended over large parts of the basin. After 3200 cal yr BP, the deepest part of the lake again turned into a wetland, which existed until c. 1600 cal yr BP. The observed lake-level rise after 1600 cal yr BP could have been caused by higher moisture availability, although increased human influence in the catchment cannot be ruled out. The present study highlights the use of multiple sediment sequences and proxies to study large lakes, such as Lake Kumphawapi in order to correctly assess the time transgressive response to past changes in hydroclimate conditions. Our new data set from northeast Thailand adds important palaeoclimatic information for a region in Southeast Asia and allows discussing Holocene monsoon variability and ITCZ movement in greater detail.

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We present data showing that arsenic (As) was codeposited with organic carbon (OC) in Bengal Delta sediments as As and OC concentrations are highly (p < 0.001) positively correlated in core profiles collected from widely dispersed geographical sites with different sedimentary depositional histories. Analysis of modern day depositional environments revealed that the As/OC correlations observed in cores are due to As retention and high OC inputs in vegetated zones of the deltaic environment. We hypothesize that elevated concentrations of As occur in vegetated wetland sediments due to concentration and retention of arsenate in aerated root zones and animal burrows where copious iron(III) oxides are deposited. On burial of the sediment, degradation of organic carbon from plant and animal biomass detritus provides the reducing conditions to dissolve iron(III) oxides and release arsenite into the porewater. As tubewell abstracted aquifer water is an invaluable resource on which much of Southeast Asia is now dependent, this increased understanding of the processes responsible for As buildup and release will identify, through knowledge of the palaeosedimentary environment, which sediments are at most risk of having high arsenic concentrations in porewater. Our data allow the development of a new unifying hypothesis of how As is mobilized into groundwaters in river flood plains and deltas of Southeast Asia, namely that in these highly biologically productive environments, As and OC are codeposited, and the codeposited OC drives As release from the sediments. We present data showing that arsenic (As) was codeposited with organic carbon (OC) in Bengal Delta sediments as As and OC concentrations are highly (p < 0.001) positively correlated in core profiles collected from widely dispersed geographical sites with different sedimentary depositional histories. Analysis of modern day depositional environments revealed that the As?OC correlations observed in cores are due to As retention and high OC inputs in vegetated zones of the deltaic environment. We hypothesize that elevated concentrations of As occur in vegetated wetland sediments due to concentration and retention of arsenate in aerated root zones and animal burrows where copious iron(III) oxides are deposited. On burial of the sediment, degradation of organic carbon from plant and animal biomass detritus provides the reducing conditions to dissolve iron(III) oxides and release arsenite into the porewater. As tubewell abstracted aquifer water is an invaluable resource on which much of Southeast Asia is now dependent, this increased understanding of the processes responsible for As buildup and release will identify, through knowledge of the palaeosedimentary environment, which sediments are at most risk of having high arsenic concentrations in porewater. Our data allow the development of a new unifying hypothesis of how As is mobilized into groundwaters in river flood plains and deltas of Southeast Asia, namely that in these highly biologically productive environments, As and OC are codeposited, and the codeposited OC drives As release from the sediments.

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This paper analyses some of the factors that impact multinational companies' (MNCs) reaction to the global financial crisis. This paper reports the results from a large-scale study of its impact on MNCs in Australia, considering occurrences of site closures, offshoring, outsourcing, labour force reductions, reductions in working hours, salary reductions, and reductions in training and travel. Evidence showed that MNC reactions varied according to certain institutional and organizational effects. For example, MNCs originating from liberal-market economies are more likely to have offshored and outsourced production and reduced employment. The implications for understanding of MNC behaviour are discussed. © 2013 Copyright Taylor and Francis Group, LLC.

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We find that regional height levels around the world were fairly uniform throughout most of the 19th century, with two exceptions: above-average levels in Anglo-Saxon settlement regions and below-average levels in Southeast Asia. After 1880, substantial diver- gences began to differentiate other regions -- making the world population taller, but more unequal. During the late 19th century and 20th century, heights between world regions devi- ated significantly, when incomes also became very unequal. Interestingly, during the “breaking point period” between the two regimes, heights declined significantly in the cattle-rich New World countries, whereas they started to increase in Old Europe. We discuss in this study whether immigration was a core factor to influence the height decline in the “Anthropometric Decline of the Cowboy and Gaucho Empires”.

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This book examines the first human colonization of Asia and particularly the tropical environments of Southeast Asia during the Upper Pleistocene. In studyexamining the unique character of the Asian archaeological record, it reassesses long-accepted propositions about the development of human ‘modernity.’ Ryan J. Rabett reveals an evolutionarily relationship between colonization, the challenges encountered during this process – especially in relation to climatic and environmental change – and the forms of behaviour that emerged. This book argues that human ‘modernity’ is not something achieved in the remote past in one part of the world, but rather is a diverse, flexible, responsive, and on-going process of adaptation, one that continues to this day.

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Renewed archaeological investigation of the West Mouth of Niah Cave, Borneo has demonstrated that even within lowland equatorial environments depositional conditions do exist where organic remains of late glacial and early post-glacial age can be preserved. Excavations by the Niah Cave Research Project (NCP) (2000-2003) towards the rear of the archaeological reserve produced several bone points and worked stingray spines, which exhibit evidence of hafting mastic and fibrous binding still adhering to their shafts. The position of both gives strong indication of how these cartilaginous points were hafted and gives insight into their potential function. These artefacts were recovered from secure and (14)C dated stratigraphic horizons. The results of this study have implications for our understanding the function of the Terminal Pleistocene and Early Holocene bone tools recovered from other regions of Island Southeast Asia. They demonstrate that by the end the Pleistocene rainforest foragers in Borneo were producing composite technologies that probably included fishing leisters and potentially the bow and arrow. (C) 2009 Elsevier Ltd. All rights reserved.

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Extensive archaeological excavations in the Niah Caves (Sarawak, Malaysian Borneo) over the past 50 years have produced perhaps 750 000 fragments of vertebrate bone, one of the largest faunal assemblages in the region, This paper introduces a series of research studies examining different aspects of the Niah fauna, and discusses how they are contributing to, and shaping, regional research agendas relating to prehistoric environments and societies in Island Southeast Asia. Zooarchaeology has traditionally had a rather 'Cinderella' status here, but the ongoing programme of study of the Niah Caves fauna is demonstrating the remarkable potential of this material to address questions of Pleistocene and Holocene climate and environment, biodiversity, human activities within caves, people's engagement with the landscapes they inhabited as foragers and farmers, and the nature of the transition from foraging to farming. Copyright (C) 2009 John Wiley & Sons, Ltd.

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During the 1950s and 1960s, excavations by the Sarawak Museum at Niah Cave in northwest Borneo produced an enormous archive of records and artefacts, including in excess of 750,000 macro- and micro-vertebrate remains. The excellent state of preservation of the animal bone, dating from the Late Pleistocene (c. 40 kya) to as recently as c. 500 years ago had the potential to provide unparalleled zooarchaeological information about early hunter-gatherer resource procurement, temporal changes in subsistence patterning, and the impact of peoples on the local and regional environment in Island Southeast Asia. However, the coarse-grained methods of excavation employed during the original investigations and the sheer scale of the archaeological record and bone assemblages dissuaded many researchers from attempting to tackle the Niah archives. This paper outlines how important information on the nature of the archaeological record at Niah has now finally been extracted from the archive using a combination of zooarchaeological analysis and reference to the extensive archaeological records from the site. Copyright (C) 2009 John Wiley & Sons, Ltd.

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Evidence for osseous technologies has featured in excavation reports from Southeast Asia for almost a century and from archaeological deposits as old as 43,000 years BP. However, in contrast to the significance that is placed on this technology in other parts of the world, until recently, Southeast Asian assemblages have drawn only very limited attention. Concentrating on evidence from Malaysia, the current paper examines one element of this inventory of tools: the deliberate modification of pig canines and the means by which such alteration can be distinguished from patterns of natural tooth wear. Particular attention is paid to the bearded pig (Sus barbatus), as it is one of the two species of wild boar in Malaysia whose tusks are most likely to have been used by prehistoric toolmakers. Reference is also made to wider, regional ethnographic examples of known tusk implements and their accredited uses to further assist in the identification process. Distinguishing criteria for worked tusk are formulated according to the type and extent of modification. These criteria are then applied to archaeological specimens recovered from two prehistoric cave sites in Malaysia, Gua Bintong and Niah Cave.