16 research outputs found

    What do we know about domestication in eastern Asia?

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    The body of data based on new work on genetics and DNA, plus a growing number of radiocarbon ages which are independent of dates based on cultural associations has broadened our knowledge of domestication in eastern Asia. Here we review the situation for several plant and animal species that were domesticated locally or imported to east Asia. Major centres of plant domestication in China have been in the Yellow and Yangtze river basins, and in Yunnan. For animals it appears that the Yellow River region, the area around Xi&#39;an and the south-east have been important centres. Many adopted domesticates have entered China through the north-west and later through ports such as Canton (Guangzhou). It appears that while there are outliers to extended ranges of wild plants and animals, sometimes not securely dated, widespread deliberate movement of plants and animals outside their natural ranges coincided with reduced hunting and gathering around 5&ndash;4&nbsp;kyr in the Longshan cultural period. The adoption of agriculture has resulted in large scale landscape transformation; forests and woodlands have been replaced by crop and grazing lands and this is evident in many late Holocene sedimentary records. This transformation continues and the patterns are changing as diets are shifting and much grain is now used to feed chicken and beef, and in addition this has placed increased pressure on water resources.</p

    Peatland development and climate changes in the Dajiuhu basin,central China, over the last 14,100 years

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    Peatlands are one of the optimal archives for paleoclimate research and their records contain a detailed history of climatic and environmental variations during their formation. Here we collected a peat profile from the Dajiuhu basin in central China and analyzed several geochemical proxies, such as Total Organic Carbon (TOC), Total Nitrogen (TN), Titanium (Ti) and Aluminum (Al), to investigate the history of peat development. The results show that the peat growth was initiated after around 12.8 cal ka BP at the sampling site and the TOC and TN contents kept stable during the Holocene except during the periods of 10.5&ndash;9.0 cal ka BP and recent 1.5 cal ka BP. However, compared with other TOC records in the Dajiuhu basin, the history of peat development varied greatly in different sampling sites, indicating that the peat development in the Dajiuhu basin probably responds to both climate changes and local geological and hydrological conditions. Investigations of the interactions between climate change and peat development record in this study suggest that peat development presented significant responses to the large and rapid decreases in East Asian Summer Monsoon intensity, such as the 9.2 ka monsoon weakening event. However, the obvious long-term decreasing trend of monsoon precipitation during the mid-late Holocene did not lead to the degradation of the Dajiuhu peat, probably resulting from relatively stable temperature. In addition, the sharp decrease of TOC and TN values in the surface 15 cm of Dajiuhu peat was probably attributed to increased human activity.</p

    Plant diversity of the Tianshui Basin in the western Loess Plateauduring the mid-Holocene e Charcoal records from archaeological sites

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    Assessing the potential impact of increased temperature needs examination of robust palaeorecords that contain analogues. The fossil charcoal (anthracological) records from the mid-Holocene archaeological sites can provide palaeo-analogues on the impacts of climate change. The Xishanping and Dadiwan sites were continuously developed during the Neolithic Culture in the Tianshui Basin, western Loess Plateau. A total of 24 samples of fossil charcoal were recovered using a floatation method. At least 100 fragments were examined from each sample, and these fragments were identified following standard procedures, and the results were used to reconstruct the vegetation and plant diversity between 5200 and 4300 cal BP, which was a warm period for the region. The charcoal evidence from the Xishanping and Dadiwan sites confirm that woody plants were widely available, including temperate taxa such as Betula, Ulmus, Quercus, Carpinus, Acer, Corylus and Padus, and typical subtropical taxa such as Bambusoideae, Liquidambar formosana, Castanopsis, Pseudotsuga sinensis, and Eucommia ulmoides. The assemblages of fossil charcoal show that mixed forests of north-subtropical evergreen and deciduous broadleaved trees existed. This is a broader range of woody plants than at present in the Tianshui Basin. This leads to the conclusion that the warmer and increasing monsoon precipitation resulted in a northward shift in the southern vegetation zones. And that the natural botanical diversity between 5200 and 4300 cal BP was also greater than at present in the Tianshui Basin, western Loess Plateau.</p

    The nature of fluctuating lakes in the southern Amu-dar'ya delta

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    The delta region of the Amu-dar'ya has a complex history of shifting river channels that has impacted extensively on the Aral Sea and on the areas of the delta that saw human settlement from prehistoric times onwards. This paper explores evidence drawn from archeological, historical and environmental data relating to lakes that formed in the south of the delta on the east bank of the river and their impact on settlement patterns in this area, in particular the potential impact of variable flooding on the major fortified site of Akchakhan-kala. Testing of the area around the sites showed that the site had not been flooded but was founded on riverine or lacustrine clays. Shortly after the initial abandonment of the site, the immediate environment was covered by dune fields

    Human activity and its impact on the landscape at the Xishanping site in the western Loess Plateau during 4800–4300 cal yr BP based on the fossil charcoal record

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    The taxonomic identification of fossil charcoal can be a useful archaeobotanical tool, as it can reveal information about prehistoric humans&#39; use of plant resources and other factors. In this study, we quantify the fossil charcoal in a cultural sequence from Xishanping in the western Loess Plateau of China representing 4800&ndash;4300 cal yr BP to consider aspects of humans&#39; impact on this landscape. The fossil charcoal assemblages reveal that the relative abundances of Picea, Betula, Acer, Ulmus and Quercus decreased markedly after 4600 cal yr BP. This suggests a marked decline in the mixed coniferous-broadleaved forest after this time. Concurrently, an increasing abundance of Bambusoideae charcoal has been suggested to reflect the expansion of the bamboo forest. The marked changes in the vegetation after 4600 cal yr BP were not obviously influenced by climate; they may be a better reflection of the results of human activity. Furthermore, other genera that provide important resources to humans also increased after 4600 cal yr BP, including Castanea, Cerasus, Padus and Diospyros. It is nearly certain that nuts and berries were an important food resource and that fruit trees were managed by prehistoric humans in the late Neolithic. This work suggests that the scale of prehistoric human impact on the western Loess Plateau landscape during the late Neolithic was much greater than was previously believed.</p

    Subsistence and the isotopic signature of herding in the Bronze Age Hexi Corridor, NW Gansu, China

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    Dietary patterns at two Bronze Age sites in the Hexi Corridor are investigated by the analysis of stable carbon and nitrogen isotopes in faunal bone collagen. The findings are compared with archaeobotanical remains from one of the sites which include high proportions of millet (Panicum miliaceum and Setaria italica) as well as the western derived cereals wheat (Triticum aestivum), barley (Hordeum vulgare) and oat (Avena sativa). The isotopic data indicate domestic omnivores (Canis and Sus) had diets dominated by millet. Minimally offset delta(15)N values between herbivore and omnivore fauna suggest low consumption of animal protein by omnivores. Diets of herded animal (Bos and Caprinae) included only low proportions of C4 foods, suggesting that these animals were not regularly foddered with millet plants, and that their grazing areas were mostly beyond the agricultural zone. The wide range in delta(15)N values amongst herbivore fauna (4.1 parts per thousand-11.8 parts per thousand) suggests grazing occurred in a variety of ecological zones, and this would be consistent with the occurrence of long-distance transport of livestock in the region.</p

    The impact of early smelting on the environment of Huoshiliang in Hexi Corridor, NW China, as recorded by fossil charcoal and chemical elements

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    Recent research has greatly increased our knowledge of early human impacts on the environment. Records of fossil charcoal and chemical elements from a bronze smelting site at Huoshiliang, in the Hexi corridor of northwest China, provide material with which to estimate the extent of smelting activity and its impact on the environment. Analysis of the microstructure of wood fossil charcoal is used to identify the types of charred wood and to reconstruct the local vegetation present during the period of smelting. Four wood types were used as firewood for smelting: Tamarix, Populus, Salix, and Polygonaceae. The assemblages of fossil charcoal showed that Tamarix was the most dominant shrub and was widely used as firewood, as a percentage of charcoal it increased from 89% to 97% over the smelting period.</p

    Early agricultural development and environmental effects in the Neolithic Longdong basin (eastern Gansu)

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    Neolithic agricultural development and environmental effects in the Longdong area were reconstructed using a synthetic approach, investigating pollen, charcoal, and seed remains for two cultural layer sections and five flotation sites. Results show that Neolithic agriculture in the Longdong area had a simple organization and was dominated by the production of common millet, especially in the early and middle Yangshao age. After the late Yangshao age, Neolithic agriculture developed into a more complex structure, dominated by both common and foxtail millet and the cultivation of rice and soybeans. The production of foxtail millet gradually increased through the Neolithic period, reaching its highest point during the Qijia culture. Soybeans were first cultivated during the late Yangshao culture, approximately 5000 cal a BP. Rice production began no later than 4800 cal a BP, and continued to exist in the Qijia culture, approximately 4000 cal a BP. Agricultural production in Neolithic Longdong, specifically in the &quot;Yuan&quot; area of the loess plateau, developed as a shrub and grass dominated landscape. Vegetation in the river valleys was partly covered with Picea, Tusga, and Quercus coniferous and broadleaf mixed forests. Agricultural activity during the Neolithic period caused an increase in farmland on the loess tableland and a decrease in the abundance of shrub and grassland in the Longdong area. When farmlands were abandoned, vegetation recovered with Hippophae-, Rosaceae-, Ephedra-, and Leguminosae-dominated shrublands and Artemisia-dominated grasslands.</p

    Towards sustainable energy. Generation ofhydrogen fuel using nuclear energy

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    The increasing demand for sustainable energy results in the development of new technologies of energy generation. The key objective of hydrogen economy is the introduction of hydrogen as main energy carrier, along with electricity, on a global scale. The key goal is the development of hydrogen-related technologies needed for hydrogen generation, hydrogen storage, hydrogen transportation and hydrogen distribution as well as hydrogen safety systems. It is commonly believed that hydrogen is environmentally clean since its combustion results in the formation of water. However, the technology currently employed for the generation of hydrogen from natural gas, does in fact lead to the emission of greenhouse gases and climate change. Therefore, the key issues in the introduction of hydrogen economy involve the development of environmentally clean hydrogen production technology as well as storage and transport. The clean options available for hydrogen generation using nuclear energy; such as advanced nuclear fission and, ultimately, nuclear fusion, are discussed. The latter, which is environmentally clean, is expected to be the primary approach in the production of hydrogen fuel at the global scale. The present work considers the effect of hydrogen on properties of TiO2 and its solid solutions in the contexts of photocatalytic energy conversion and the effect of tritium on advanced tritium breeders.</p

    Land degradation during the Bronze Age in Hexi Corridor(Gansu, China)

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    Pollen and charcoal analysis, with high resolution AMS C-14 dating, on two sediment sections in the Hexi Corridor track the process of settlement development and abandonment during the Bronze Age. The evidence shows that agricultural activity during the Bronze Age caused an increase in farmland and a decrease in the abundance of Artemisia grassland in the Hexi Corridor. Land degradation is probably the main cause for decreased agricultural activity and settlement abandonment. Agriculture- induced soil fertility loss and land salinization contributed to the process of land degradation. However, increasing climate aridity around 4000-3500 cal BP is probably the main initiating cause for the contraction of arable land and vegetation degradation in the Hexi Corridor.</p
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