2,119 results
Search Results
202. The Impacts of the Middle Holocene High Sea-Level Stand and Climatic Changes on Mangroves of the Jucuruçu River, Southern Bahia – Northeastern Brazil.
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Fontes, Neuza Araújo, Moraes, Caio A., Cohen, Marcelo C L, Alves, Igor Charles C., França, Marlon Carlos, Pessenda, Luiz C R, Francisquini, Mariah Izar, Bendassolli, José Albertino, Macario, Kita, and Mayle, Francis
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HOLOCENE Epoch ,SEA level ,CLIMATE change ,ALLUVIUM - Abstract
The aim of this paper is to evaluate the compatibility between the Holocene relative sea-level (RSL) curves proposed for the Brazilian littoral and mangrove dynamics along a fluvial valley in the state of southern Bahia. This was done integrating geomorphological, sedimentological, palynological, and stable isotopic data from two cores collected at the mouth of the Jucuruçu River and at a site 23 km inland, near the city of Prado, northeastern Brazil. Core PR07, sampled from a fluvial plain at about 4.5±1 m above the RSL, reveals mangrove pollen (5–20%) and estuarine/terrestrial organic matter (δ13C=~–25‰, C/N=7.3–67) between 4.5 m (~7400 cal yr BP) and 1.75 m depth (~5350 cal yr BP). Core PR11, sampled from a mangrove tidal flat, also revealed mangrove pollen taxa (5-28%) since 660 cal yr BP. Core PR07 indicated absence of mangrove pollen and increase of sedimentary organic matter sourced from terrestrial C3 plants (δ13C=~–27‰, C/N=22–159) during the last 5350 cal yr BP. Probably, the changes in vegetation and sedimentary organic matter identified in core PR07 were caused by the combined effects of the RSL fluctuations, with a highstand at about 5350 cal yr BP of 2.7±1.35 m, and changes in fluvial discharge. [ABSTRACT FROM AUTHOR]
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- 2017
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203. Soils of loamy watersheds of coastal tundra in the north of Yakutia: Pedogenetic conditions and processes.
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Gubin, S. and Lupachev, A.
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LOAM soils ,WATERSHEDS ,TUNDRAS ,METAMORPHIC rocks ,DRAINAGE - Abstract
This paper considers regularities governing the formation of automorphic tundra soils on glacial loamy deposits containing relict organic matter mainly represented by very fine plant detritus. Drainage, microtopography, and cryoturbation activity are the major controls of the development of these soils. With an increase in drainage, the following pedogenetic trend is observed on the surface of yedoma (Ice Сomplex) areas: gleyzem-cryozem-cryometamorphic soil. The climate change in the Holocene induced quick transformation of topography and general landscape situation and promoted formation and development of cryogenic soil complexes in the considered territory. Upon the low intensity of pedogenesis, the features and properties of previous soil formation stages are often preserved in the soil profiles; these are: gleyzation, peat accumulation, and cryoturbation. [ABSTRACT FROM AUTHOR]
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- 2017
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204. Assessing Late Pleistocene and Holocene phases of aeolian activity on the Nyírség alluvial fan, Hungary.
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Buró, Botond, Sipos, György, Lóki, József, Andrási, Bence, Félegyházi, Enikő, and Négyesi, Gábor
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ALLUVIAL fans , *PLEISTOCENE Epoch , *SAND dunes , *RADIOCARBON dating - Abstract
There have been several studies addressing the timing and extension of Late Pleistocene and Holocene Aeolian activity in the Nyírség, the former alluvial fan of the Tisza River. Some of these already applied numerical dating techniques, however usually focused on one dune form or one site. This paper is an attempt on the one hand to review former age data and on the other hand to add new data from various sites to the landform evolution of the second largest sand dune area of the Carpathian Basin. The paper focuses on the Late Pleistocene–Holocene landform evolution of the second largest sand dune area of Hungary (Nyírség). Recent age data were obtained from investigations applying several methods (radiocarbon, OSL and palynological examinations) in order to determine the periods of sand movement and paleosoil formation in the area more accurately. According to the results, six sand movement periods can be identified during the Late Glacial and Holocen (Oldest Dryas, Younger Dryas, Preboreal Phase, Boreal Phase, Atlantic Phase, Subatlantic Phase). In between periods with intensive aeolian activity paleosoil formation occurred in the Bølling-Allerød Interstadial and in the Preboreal and Subatlantic Phases. [ABSTRACT FROM AUTHOR]
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- 2016
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205. Built structures in rockshelters of the Pilbara, Western Australia.
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Wallis, Lynley A. and Matthews, Jacqueline
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CAVES ,BUILT environment - Abstract
Built structures in rockshelters are relatively common archaeological features in the Pilbara that have been neglected in the published literature Drawing primary on grey literature, coupled with new data from recent investigations, this paper provides a review of current knowledge about these enigmatic structures. Results show that these features are found across the Hamersley Plateau, although are especially abundant in the Packsaddle Range, and in the Chichester Ranges. Most are likely to be late Holocene features, concurrent with a suite of other oranges that occurred during that period. The current practice of grouping all built structures in rockshelters into a single site type (i.e. '(hu)man-made structures') conceals wide variation amongst then. A typology is suggested based on morphological and contextual features to allow better characterisation of these features, thereby improving understandings of their distribution and functions, and facilitating more adequate assessments of their significance in management contexts. [ABSTRACT FROM AUTHOR]
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- 2016
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206. On the timing of the East Asian summer monsoon maximum during the Holocene-Does the speleothem oxygen isotope record reflect monsoon rainfall variability?
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Chen, JianHui, Rao, ZhiGuo, Liu, JianBao, Huang, Wei, Feng, Song, Dong, GuangHui, Hu, Yu, Xu, QingHai, and Chen, FaHu
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MONSOONS ,RAINFALL ,SPELEOTHEMS ,STALACTITES & stalagmites ,OXYGEN isotopes - Abstract
The evolution of the East Asian summer monsoon (EASM) during the Holocene has long been of significant interest. Knowledge of past EASM variability not only increases our understanding of monsoon dynamics on a long timescale, but it also provides an environmental and climatic background for research into Chinese cultural development. However, the timing of the EASM maximum remains controversial. The popular concept of an 'early Holocene maximum' is mainly based on speleothem δO ( δ O) records from caves in southern China; however, the interpretation of δ O as a reliable proxy for EASM intensity is being increasingly challenged. The present paper is a critical review of the climatic significance of the δ O record from China. Firstly, we suggest that precipitation in northern China is an appropriate index of EASM intensity, the variation of which clearly indicates a mid-Holocene monsoon maximum. Secondly, an interregional comparison demonstrates that the precipitation record in northern China is quite different from that in southern China on a range of timescales, and is inconsistent with the spatial similarity exhibited by speleothem oxygen isotope records. Furthermore, both modeling and observational data show that the δ Oc records from southern China indeed reflect changes in precipitation δ O ( δ O) rather than precipitation amount, and therefore that their use as an EASM proxy is inappropriate. Finally, we address several significant monsoon-related issues-including the driving mechanism of the EASM on an orbital timescale, the climatic significance of speleothem oxygen isotopes, and the relationship between atmospheric circulation and precipitation in monsoonal regions. [ABSTRACT FROM AUTHOR]
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- 2016
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207. Fire, people and ecosystem change in Pleistocene Australia.
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Johnson, Christopher N.
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Since the 1960s, Australian scientists have speculated on the impact of human arrival on fire regimes in Australia, and on the relationship of landscape fire to extinction of the Pleistocene megafauna of Australia. These speculations have produced a series of contrasting hypotheses that can now be tested using evidence collected over the past two decades. In the present paper, I summarise those hypotheses and review that evidence. The main conclusions of this are that (1) the effects of people on fire regimes in the Pleistocene were modest at the continental scale, and difficult to distinguish from climatic controls on fire, (2) the arrival of people triggered extinction of Australia's megafauna, but fire had little or no role in the extinction of those animals, which was probably due primarily to hunting and (3) megafaunal extinction is likely to have caused a cascade of changes that included increased fire, but only in some environments. We do not yet understand what environmental factors controlled the strength and nature of cascading effects of megafaunal extinction. This is an important topic for future research. [ABSTRACT FROM AUTHOR]
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- 2016
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208. Can people change the ecological rules that appear general across space?
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Šizling, A. L., Pokorný, P., Juřičková, L., Horáčková, J., Abraham, V., Šizlingová, E., Ložek, V., Tjørve, E., Tjørve, K. M. C., Kunin, W., and Kerr, Jeremy
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BIODIVERSITY ,HUMAN behavior ,SNAILS ,HOLOCENE Epoch ,PLANT remains (Archaeology) - Abstract
Aim Projections of human impact on the environment and biodiversity patterns are crucial if we are to prevent their destruction. Such projections usually involve the assumption that the same human activities always affect biodiversity in the same way, either in geographically distant areas within the same time-scale or in the same areas in different periods. In this paper, plant and snail fossils from central Europe that cover the last 12,000 years provide evidence against this assumption. Location Central Europe. Methods We examined fossil data on central European plants and snails and extracted time-series of (1) local species richness (alpha diversity) at a scale of approximately 300 m × 300 m and decays of (2) the Jaccard index and (3) Simpson's beta with increasing distance (up to approximately 400 km) through time. Results We show that two vital biodiversity patterns follow neither oxygen-isotope nor borehole temperature proxies, but instead vary between archaeologically known periods, with the most noticeable and irreversible breaks (1) when arable agriculture was introduced into central Europe, (2) when the Roman Empire collapsed, and (3) during the event known as the 12th-century colonization in central Europe. The patterns computed from data across time sometimes contradicted the patterns computed across space. Main conclusions We therefore infer that people can, and sometimes have, contributed to temporal changes in ecological rules that are seemingly general across space. Our findings indicate that the changes in ecological rules are so substantial that efforts to project future biodiversity based on space-for-time substitution might fail, unless we gain knowledge about how these general rules are altered. [ABSTRACT FROM AUTHOR]
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- 2016
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209. Holocene woodland history of the Sierra de Ayllón (central Spain)
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García-Antón, Mercedes, Génova, Mar, Postigo-Mijarra, José María, García-Álvarez, Salvia, Morla, Carlos, and García-Amorena, Ignacio
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- 2021
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210. Targeting the Mesolithic: Interdisciplinary approaches to archaeological prospection in the Brown Bank area, southern North Sea.
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Missiaen, Tine, Fitch, Simon, Harding, Rachel, Muru, Merle, Fraser, Andy, De Clercq, Maikel, Moreno, David Garcia, Versteeg, Wim, Busschers, Freek S., van Heteren, Sytze, Hijma, Marc P., Reichart, Gert-Jan, and Gaffney, Vince
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MESOLITHIC Period , *IMAGING systems in seismology , *ARCHAEOLOGICAL finds , *SEISMIC surveys , *HOLOCENE Epoch , *BANKING industry , *PROSPECTING - Abstract
This paper describes some results of the research undertaken over the Brown Bank area during recent (2018/2019) geoarchaeological surveys in the North Sea which included seismic imaging, shallow (vibro)coring and dredging. It examines the benefits of simultaneous high-resolution (0.5 – 1 m) and ultra-high-resolution (10–20 cm) seismic survey techniques and a staged approach to resolving the submerged Holocene landscape in the highest possible detail for the purpose of targeted prospecting for archaeological material from the Mesolithic landscape of Doggerland. The materials recovered from such surveys offer significantly greater information due to an enhanced understanding of the context in which they were recovered. The importance of this information cannot be understated archaeologically, as few locations on land provide the opportunity to recover archaeological finds in situ within preserved landscapes. Moreover, it allows offshore areas of potential human activity to be prospected with some certainty of success. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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211. Peatland initiation in Central European Russia during the Holocene: Effect of climate conditions and fires.
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Novenko, Elena Yu, Mazei, Natalia G, Kupriyanov, Dmitry A, Kusilman, Maria V, and Olchev, Alexander V
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HOLOCENE Epoch , *CHARCOAL , *ECOLOGICAL zones , *FOREST soils , *SURFACE topography , *WATERLOGGING (Soils) , *PALEOECOLOGY - Abstract
Peatlands store massive amounts of organic carbon, but the fate of this carbon remains unclear as global climate continues to warm. The age of peatland inception and the main drivers of peat initiation are one of the most important issues in Holocene paleoecology, especially for the numerous but under investigated peatlands in European Russia. This paper introduces new peatland initiation ages for 44 mires in three areas located in the central part of European Russia within the Polesie landscape belt. This region is characterised by waterlogged sandy plains and flat surface topography. Phases of peatland initiation were compared with Holocene fire regime derived from macro-charcoal data as well as with regional climatic reconstructions. We found that peat inception in the region started around 12,000 cal yr BP, but the most active phases of peatland initiation took place during the periods 8500–7500, 7000–6000, 5300–5800, 4000–3500 and 1700–1200 cal yr BP. Expect for rapid peat growth during the early Holocene, peatland initiation mostly coincided with warm climatic periods and increased fire frequency. Forest soil paludification in poorly drained Polesie landscapes was presumably enhanced by reduced evapotranspiration and changes in water balance due to disturbance of forest cover after wildfires. We expect that rising air temperature in the current century will cause higher fire frequencies and may encourage waterlogging of forests and ecosystem transformation. [ABSTRACT FROM AUTHOR]
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- 2021
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212. The Holocene paleoenvironmental history of Western Caucasus (Russia) reconstructed by multi-proxy analysis of the continuous sediment sequence from Lake Khuko.
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Grachev, Alexei M, Novenko, Elena Y, Grabenko, Evgeniy A, Alexandrin, Mikhail Y, Zazovskaya, Elya P, Konstantinov, Evgeniy A, Shishkov, Vasiliy A, Lazukova, Lyudmila I, Chepurnaya, Anna A, Kuderina, Tatiana M, Ivanov, Maxim M, Kuzmenkova, Natalia V, Darin, Andrei V, and Solomina, Olga N
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SEDIMENT analysis , *ACCELERATOR mass spectrometry , *LAKE sediments , *HOLOCENE Epoch , *POLLEN , *VEGETATION boundaries , *OAK , *LINDENS - Abstract
This paper presents new multi-proxy records of the Holocene environmental and climatic changes in the Western Caucasus revealed from a continuous sediment sequence from mountainous Lake Khuko (Caucasus State Natural Biospheric Reserve, 1744 m a.s.l.). Palaeoecological analyses of a sediment core for grain size, magnetic susceptibility, loss on ignition, and pollen allowed us to determine five principal climatic phases with several subphases since 10.5 ka BP. The age model is based on seven accelerator mass spectrometry 14C dates, supplemented by 210Pb data for the uppermost part of the sediment core. Warm periods (10.5–6.7, 6.7–5.5, 3.5–2.4, 0.8–0.5 ka BP) were characterized by high biological productivity in the lake as indicated by high organic matter content and expansion of forests, typical of modern low and middle mountain zones, as indicated by the increase in abundance of Quercus, Ulmus, Corylus, and Tilia in the pollen assemblages. Cold periods (5.5–3.5, 2.4–0.8, and 0.5 ka BP–present) are marked by a consistent decrease in organic matter content in lake deposits and possibly higher intensity of the catchment erosion. The changes in pollen assemblages (for instance peaks of Abies, Picea, and Pinus) suggested a potential elevational decline in the boundaries of vegetation belts and expansion of high-altitude woodlands. Abrupt changes in the lake ecosystem were identified between 4.2 and 3.5 ka cal BP marked by a short-term variation in sediment regime shown by variation in organic matter content, magnetic susceptibility values, and sediment grain size. This was probably caused by climatic fluctuations in the Western Caucasus region as a result of complex shifts in the ocean-atmosphere system during the 4.2 ka event. Overall, the first Holocene multi-proxy continuous lake sediment record provides new insights into the climate history in the Western Caucasus. [ABSTRACT FROM AUTHOR]
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- 2021
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213. Formation and evolution of barrier coast under condition of sand scarcity; an example from the Polish coast of the southern Baltic sea.
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Sydor, Paweł and Uścinowicz, Szymon
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CORE drilling , *COASTS , *ABSOLUTE sea level change , *SAND , *SCARCITY , *SEA level - Abstract
The formation and evolutionary history of intracontinental, tideless sea barrier coasts is still poorly known in comparison to open-ocean and tidal sea barrier systems. This paper describes the morpho-geological structure of the barriers and its substrate along a 90-km section of the middle part of the Polish southern Baltic coast. The main goal of the study is a better insight into the evolution of the barriers in case of sand scarcity and relations to sea level changes. The study area was examined by analysis of the published and historical data from 120 borehole profiles supplemented by new 18 core drillings. In addition to lithological and biostratigraphical data, a large set of radiocarbon ages was acquired and analysed. The barriers during its whole middle and late Holocene history were retrogradational despite of varied geological and morphological features of its substrate. The average rate of barrier's retreat has shown considerable variation in a close relation to the rates of sea-level rise. During the period 8500-7500 yr b2k when the sea level rose by 6–5 mm/yr, the coast retreated ca. 4.6–3.5 m/yr. Between 7500 and 6000 yr b2k, the sea-level rise slowed down to ca. 1.7 mm/yr and the rate of coastline retreat fell to ca. 1.0 m/yr. During the last 6000 years, coastal retreat slowed down to ca. 0.3 m/yr as the average sea level rise was ca. 0.5 mm/yr. The permanent retrogradational history of the barrier coast, even in the case of sand availability in the barrier's substrate, is explained by the existence of a divergence zone of longshore currents and a related source zone for the alongshore sandy streams. The divergence zone is present within the study area not only today, but it has existed most probably also at least since the beginning of the late Holocene. As a result, the erosional trend (sand scarcity) dominates here, which contributes to the presence of retrogradational barriers. • Recognition of morpho-geological structure of the barrier and its substrate. • New middle and late Holocene relative sea-level curve from southern Baltic Sea. • The evolution of the barriers in case of sand scarcity and relations to sea level changes. [ABSTRACT FROM AUTHOR]
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- 2024
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214. Holocene marine deposits in the Bohai Sea: Depocenters, sediment sources, and oceanic and tectonic influences.
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Li, Xishuang, Zhao, Yuexia, Yang, Zuosheng, Qiao, Shuqing, Liu, Baohua, Xie, Qiuhong, Saito, Yoshiki, and Liu, Chenguang
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MARINE sediments , *HOLOCENE Epoch , *SEDIMENTS , *FAULT zones , *ESTUARIES , *NEOTECTONICS - Abstract
The Bohai Sea is a semi-enclosed shallow shelf sea that has undergone a unique sediment source-to-sink process in the past. Despite this, our knowledge about the sediment budget, existence of depocenters and the factors controlling depocenter formation during the Holocene remains limited. This paper aims to address these gaps by estimating the Holocene marine deposit thickness and sediment budget in the Bohai Sea using high-resolution subbottom profiles. The results reveal that the mean thickness of Holocene marine deposits is approximately 7.8 m and a maximum thickness of 28 m was found in Jinzhou Bay. The Highstand System Tracts (HST) have a mean thickness of approximately 5.4 m and a maximum thickness of 25 m observed in the Jinzhou Bay. On the other hand, the Transgressive System Tracts (TST) have a mean thickness of approximately 2.5 m and a maximum thickness of 7 m in the north of the Laizhou Bay. The total accumulation in the Bohai Sea is estimated to be ∼713.97 × 109 tons, consisting of 489.28 × 109 tons from the HST and 224.69 × 109 tons from the TST. Three deposit centers were identified and estimated to be approximately 299 × 109 tons, accounting for approximately 42 % of the total Bohai Sea sediments. The development of Holocene marine deposit centers was mainly influenced by the Tanlu Fault zone and water circulations. Based on preliminary estimates, it is suggested that roughly half of the sediments dispersed from the estuaries are preserved on the Bohai Sea shelf since the maximum flooding (∼7000 cal yr BP). This research provides valuable insights for the post-glacial sedimentary and geomorphic evolution of the Bohai Sea. • Holocene marine accumulation in the Bohai Sea is estimated to be ∼713.97 × 109 tons. • Accumulation in HST is of ∼489.28 × 109 tons and that in TST is of ∼224.69 × 109 tons. • Three depocenters were identified and account for ∼42 % of the total accumulation. • Roughly half of the sediments were preserved on the shelf over the past 7000 years. [ABSTRACT FROM AUTHOR]
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- 2023
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215. Colour in context. Pigments and other coloured residues from the Early-Middle Holocene site of Takarkori (SW Libya)
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di Lernia, Savino, Bruni, Silvia, Cislaghi, Irina, Cremaschi, Mauro, Gallinaro, Marina, Gugliemi, Vittoria, Mercuri, Anna Maria, Poggi, Giansimone, and Zerboni, Andrea
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- 2016
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216. Assessing changes in global fire regimes.
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Sayedi, Sayedeh Sara, Abbott, Benjamin W., Vannière, Boris, Leys, Bérangère, Colombaroli, Daniele, Romera, Graciela Gil, Słowiński, Michał, Aleman, Julie C., Blarquez, Olivier, Feurdean, Angelica, Brown, Kendrick, Aakala, Tuomas, Alenius, Teija, Allen, Kathryn, Andric, Maja, Bergeron, Yves, Biagioni, Siria, Bradshaw, Richard, Bremond, Laurent, and Brisset, Elodie
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FIRE management ,EFFECT of human beings on climate change ,BIOMES ,FIRE ecology ,GRASSLANDS ,CLIMATE sensitivity ,ECOSYSTEM services ,PLANT communities - Abstract
Copyright of Fire Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2024
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217. Mechanism and genesis of Sanmen Bay as a sink of Holocene Yangtze River sediment, Zhejiang Province, China.
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Qiu, Jiandong, Jiang, Shenghui, Wang, Jianqiang, Feng, Jing, Chen, Junbing, Dong, Chao, Jiang, Yunshui, and Zhang, Daolai
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RIVER sediments ,ACCELERATOR mass spectrometry ,HOLOCENE Epoch ,SEDIMENT sampling ,DRILL core analysis ,CLAY minerals - Abstract
Introduction: The Holocene mud deposits that extend from the Yangtze River mouth to the Taiwan Strait along the Zhejiang-Fujian coast, East China Sea (ECS), have attracted considerable research attention. However, there is a lack of consensus regarding the redistribution flux of Yangtze River sediment after it enters the sea. There are many bays along the Zhejiang and Fujian coasts, but their role in the source-sink process of Yangtze River sediment is not well-documented owing to limited data. Methods: In this study, data from shallow seismic profiles, core samples, and surface sediment samples were analysed to assess the role of Sanmen Bay, the second largest bay in Zhejiang Province, in the source-sink process of Yangtze River sediments. Results: The results showed that Sanmen Bay is an important sink for Yangtze River sediments. The characteristics of the clay minerals indicate that the finegrained sediments in Sanmen Bay are mainly derived from Yangtze River sediments. The thickness of Holocene deposits in Sanmen Bay ranges from 8.2 to 32.0 m, with an average of 23.4 m and a total sediment volume of 5.06 x 10[sup 4] Mt, accounting for 1% of Yangtze River sediment in this time period. The Bayesian age-depth model based on borehole accelerator mass spectrometry (AMS) [sup 14]C dating shows that a high sedimentation rate occurred in the early and late Holocene but decreased significantly in the mid-Holocene, which is similar to that of the inner shelf of the East China Sea (ECS). Conclusion: The variation in the Holocene sedimentation rate in Sanmen Bay is related to the southward transport process and mechanism of Yangtze River sediments. The results of this study provide a basis for understanding the source-sink process of sediment in large rivers. [ABSTRACT FROM AUTHOR]
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- 2024
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218. Millennial‐Scale Changes in Atmospheric Nitrous Oxide During the Holocene.
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Azharuddin, Syed, Ahn, Jinho, Ryu, Yeongjun, Brook, Ed, and Salehnia, Nasrin
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ATMOSPHERIC nitrous oxide ,STALACTITES & stalagmites ,HOLOCENE Epoch ,ICE cores ,NITROUS oxide - Abstract
Nitrous oxide (N2O) is an important greenhouse gas which destroys the ozone in the stratosphere. Primary sources of atmospheric N2O are nitrification and denitrification in terrestrial soils and the ocean, and the main sink is photolysis in the stratosphere. Studies have mostly focused on the climate‐related response of N2O during glacial‐interglacial periods. However, its mechanism of variation during the Holocene remains unclear. We present a high‐resolution N2O record from the South Pole Ice (SPICE) core covering the Holocene epoch. The millennial‐scale N2O trend agrees with existing records. We constructed a Holocene composite consisting of the new N2O measurements in SPICE and existing records from other ice core sites. The N2O composite reveals four distinct periods of N2O variation during 11.5–10.0 ka, 10.0–6.2 ka, 6.2–2.2 ka, and 2.2–1.4 ka, including two maxima in 11.0–10.0 ka and 3.0–2.2 ka and minima in 8.8–6.2 ka and approximately 1.4 ka. Apart from these, our new high‐resolution record from SPICE shows a short‐term N2O decrease around 2.8 ka which is not observed in other records possibly due to lower sample resolution and/or higher age smoothing. Comparison of our new Holocene N2O composite with the paleo‐proxy records suggests the plausible linkage of major monsoon (Asian, North African, South and North American, and Australian‐Indonesian monsoon) and upwelling (Arabian Sea and Eastern Tropical South Pacific) regions in regulating the atmospheric N2O during the Holocene. Plain Language Summary: Nitrous oxide (N2O) is an important greenhouse and ozone‐depleting gas. The growing level of N2O in the atmosphere is of global concern, and records of past N2O variations can provide an essential context for understanding the links between N2O and climate change. In this study, we report a new, high‐quality N2O record covering the Holocene epoch using an ice core obtained from the South Pole. Our record shows four important periods of N2O variation during 11.5–10.0 ka, 10.0–6.2 ka, 6.2–2.2 ka, and 2.2–1.4 ka. These include two local N2O maxima in 11.0–10.0 ka and 3.0–2.2 ka and minima in 8.8–6.2 ka and approximately 1.4 ka. Comparison with climate records suggests that the variation in monsoon precipitation and ocean productivity contributed to centennial‐ to millennial‐scale N2O variations during the Holocene. Key Points: High‐resolution N2O record from the South Pole Ice core covering the Holocene epoch is investigated for N2O variationInsight into the key drivers of atmospheric N2O on millennial time scales during the Holocene is providedN2O exhibits two local maxima during 11.0–10.0 ka and 3.0–2.2 ka, and two local minima during 8.8–6.2 ka and at around 1.4 ka [ABSTRACT FROM AUTHOR]
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- 2024
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219. Holocene temperature variation recorded by branched glycerol dialkyl glycerol tetraethers in a loess-paleosol sequence from the north-eastern Tibetan Plateau.
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Wang, Tianxiao, Wu, Duo, Wang, Tao, Chen, Lin, Guo, Shilong, Li, Youmo, and Zhang, Chenbin
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Reconstructing Holocene temperature evolution is important for understanding present temperature variations and for predicting future climate change, in the context of global warming. The evolution of Holocene global temperature remains disputed, due to differences between proxy reconstructions and model simulations, a discrepancy known as the 'Holocene temperature conundrum'. More reliable and quantitative terrestrial temperature records are needed to resolve the spatial heterogeneity of existing records. In this study, based on the analysis of branched glycerol dialkyl glycerol tetraethers (brGDGTs) from a loess-paleosol sequence from the Ganjia Basin in the north-eastern Tibetan Plateau (NETP), we quantitatively reconstructed the mean annual air temperature (MAAT) over the past 12 ka. The MAAT reconstruction shows that the temperature remained low during the early Holocene (12–8 ka), followed by a rapid warming at around 8 ka. From 8 to 4 ka, the MAAT record reached its highest level, followed by a cooling trend from the late Holocene (4–0 ka). The variability of the reconstructed MAAT is consistent with trends of annual temperature records from the Tibetan Plateau (TP) during the Holocene. We attribute the relatively low temperatures during the early Holocene to the existence of ice sheets at high-latitude regions in the Northern Hemisphere and the weaker annual mean insolation at 35°N. During the mid to late Holocene, the long-term cooling trend in the annual temperature record was primarily driven by declining summer insolation. This study provides key geological evidence for clarifying Holocene temperature change in the TP. [ABSTRACT FROM AUTHOR]
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- 2023
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220. Detecting the spatial-temporal pattern of moisture evolution on the Tibetan Plateau during the Holocene by model-proxy comparison.
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Zheng, Zeyu, Jin, Liya, Li, Jinjian, Zhang, Xiaojian, and Chen, Jie
- Abstract
The Tibetan Plateau (TP) is a key region for environmental and climatic research due to its significant linkages with large-scale atmospheric circulation. Understanding the long-term moisture evolution pattern and its forcing mechanisms on the TP during the Holocene may provide insights into the interaction between low-latitude climate systems and midlatitude westerlies. Here, we synthesized 27 paleoclimate proxy records covering the past 9500 years. The results of the rotated empirical orthogonal function analysis of the moisture variation revealed spatial-temporal heterogeneity, which was classified into 5 subregions. Proxy records were then compared with the results from the Kiel Climate Model and other paleorecords. The results showed that moisture evolution on the western-southern-central TP was controlled by the Indian summer monsoon (ISM). On the south-eastern TP, moisture change was affected by the interplay between the East Asian summer monsoon (EASM) and the westerlies, as well as the ISM. With diverse patterns of circulation system precipitation, moisture changes recorded in the paleorecords showed spatial-temporal discrepancies, especially during the early to middle Holocene. Moreover, given the anti-phase pattern of summer precipitation in the EASM area under El Niño/Southern Oscillation (ENSO) conditions and the unstable relationship between the ISM and ENSO, it is reasonable to conclude that relatively strong ENSO variability during the late Holocene has contributed to these discrepancies as Asian summer monsoon precipitation has declined. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
221. Holocene Depositional History of Low-Lying Reef-Rim Carbonate Islets of Fakarava Atoll, Northwest Tuamotu, Central South Pacific.
- Author
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Montaggioni, Lucien F., Salvat, Bernard, Pons-Branchu, Edwige, Martin-Garin, Bertrand, Dapoigny, Arnaud, Brunaud, Éric, Poli, Gilbert, and Tatarata, Miri
- Subjects
CORAL reefs & islands ,ISLANDS ,HOLOCENE Epoch ,WINTER storms ,SEA level ,CYCLONES ,GLOBAL warming - Abstract
Assumptions about the fate of low-lying coral reef islands (atolls) facing global warming are poorly constrained, due to insufficient information on their depositional history. Based on the U/Th dating of 48 coral clasts, the chronostratigraphic analysis of excavated sections through rim islets (motu) at the windward and leeward sides of Fakarava Atoll (Tuamotu, French Polynesia) reveal that the deposition of coral detritus started approximately 2000 years ago. Most of these deposits lie on conglomerate pavements or reef flat surfaces, and are about 4500 to 3000 years old. The islet expansion at the windward sites seems to have operated coevally across the reef rim, from the ocean-facing shore lagoonwards. Meanwhile, well-developed, continuous, elongated, vegetated islets mostly occur along the windward, northeast to southeast coast, and isolated islets, vegetated or not, associated with the dense networks of conglomerates, are common on the leeward, partly submerged, western rim. Islet accretion on the windward rim sides is believed to have been mainly triggered by winter storms and occasional cyclonic events, whilst the leeward atoll parts were most likely shaped by distant-source swells from mid to high latitudes. The projections of the accelerated sea level rise in the future suggest that the long-term islet stability at Fakarava could be altered because the islets have accreted under the conditions of the falling sea level. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
222. The role of post UK-LGM erosion processes in the long-term storage of buried organic C across Great Britain – A 'first order' assessment.
- Author
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Tye, A.M., Evans, D.L., Lee, J.R., and Robinson, D.A.
- Subjects
- *
LAST Glacial Maximum , *EROSION , *HISTORY of geology , *GEOMORPHOLOGY , *GEOLOGY - Abstract
Increasing consideration is being given as to whether and how the subsoil can be utilised as a resource to store greater quantities of organic carbon through a range of 'frontier' technologies. However, recent work suggests 'priming' effects may occur when fresh soil organic carbon (SOC) is mixed with older organic carbon (OC). Combined with increasing intensity of land use and perturbation of the surface environment there is potential for buried organic carbon (OC) to be re-incorporated into the active global C cycle. Therefore, understanding the nature of existing buried organic carbon (OC) within Soil Parent Material (SPM) and landscapes is increasingly important. A major OC burial route within landscapes is via erosion and deposition processes. This paper aims to provide a 'first order' overview of the role erosion processes have made since the UK Last Glacial Maximum (UK-LGM) in the burial of OC in Great Britain. Using collated information, Monte-Carlo simulations were used to produce 'first-order' estimates of the mass of OC buried within three deposit types; Devensian Till, Devensian Glacio-fluvial deposits and Holocene Alluvium. Combined median estimates for these three deposit types alone suggest, that 385 MT of OC has been buried in these deposits across Great Britain, demonstrating the importance of post UK-LGM erosion processes in long-term sequestration of OC. The paper provides a basis of a framework to describe where buried OC may be found within UK SPM and landscapes, whilst identifying gaps in our knowledge base. Whilst focusing on Great Britain, the processes are relevant to many countries, each of which will have experienced erosion processes unique to their own history of geology, geomorphology and climate. • Post UK-LGM erosion processes are assessed in relation to organic carbon burial. • The climate-vegetation-erosion concept was used to assess erosion processes. • Climate helped determine deposit thickness and carbon concentration. • Estimates of organic carbon burial in selected deposit types were 385 Mt C. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
223. Geomorphology, Stratigraphy and Tectonics of the Mesopotamian Plain, Iraq: A Critical Review
- Author
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Sissakian, V. K., Al-Ansari, N., and Adamo, N.
- Published
- 2021
- Full Text
- View/download PDF
224. The Archaeology of Pig Domestication in Eurasia
- Author
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Price, Max and Hongo, Hitomi
- Published
- 2020
- Full Text
- View/download PDF
225. Holocene dust dynamics archives in archaeological ruins in arid and semi-arid environments in the Southern Levant
- Author
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Lucke, Bernhard and Bäumler, Rupert
- Published
- 2021
- Full Text
- View/download PDF
226. Formation and decay of peat bogs in the vegetable belt of Switzerland
- Author
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Egli, Markus, Wiesenberg, Guido, Leifeld, Jens, Gärtner, Holger, Seibert, Jan, Röösli, Claudia, Wingate, Vladimir, Dollenmeier, Wasja, Griffel, Pascal, Suremann, Jeannine, Weber, Jan, Zyberaj, Mergime, and Musso, Alessandra
- Published
- 2021
- Full Text
- View/download PDF
227. Holocene hunter-gatherers and adhesive manufacture in the West Coast of South Africa.
- Author
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Charrié-Duhaut, Armelle, Porraz, Guillaume, Igreja, Marina, Texier, Pierre-Jean, and Parkington, John E.
- Subjects
HUNTER-gatherer societies ,ADHESIVE manufacturing ,HOLOCENE Epoch ,BIOMOLECULAR archaeology ,ANTIQUITIES - Abstract
Elands Bay Cave provides the opportunity to characterize Holocene technologies and hunter-gatherers adaptations in the West Coast of South Africa. In this paper, we discuss the question of adhesives uses and manufactures by applying a biomolecular and technological analysis to three unpublished organic artefacts recovered from the 1970s excavation. The first piece is a large handle made of adhesive and with a tear-drop shape (the 'handle'), the second piece is a kind of pencil grip wrapping a microlithic quartz segment (the 'grip'), and the last piece takes the form of a macro-residue likely sealing the perforation of an ostrich eggshell flask (the 'sealant'). The results of our study document the selection and transformation of Podocarpus resin, mixed with quartz sand to produce adhesive. One case study (the sealant) suggests that fat was added to the recipe in order to modify the adhesive's properties. The paper provides a unique insight into Holocene organic technologies and fuels ideas on how hunter-gatherers adapted and took benefit from local natural resources. We suggest that Podocarpus, in South Africa, has been specifically chosen for adhesive manufacture since, at least, the MIS4. [ABSTRACT FROM AUTHOR]
- Published
- 2016
228. Fire, climate and vegetation linkages in the Bolivian Chiquitano seasonally dry tropical forest.
- Author
-
Power, M. J., Whitney, B. S., Mayle, F. E., Neves, D. M., de Boer, E. J., and Maclean, K. S.
- Subjects
FOREST fires ,TROPICAL forests ,FORESTRY & climate ,VEGETATION & climate ,CHARCOAL - Abstract
South American seasonally dry tropical forests (SDTFs) are critically endangered, with only a small proportion of their original distribution remaining. This paper presents a 12 000 year reconstruction of climate change, fire and vegetation dynamics in the Bolivian Chiquitano SDTF, based upon pollen and charcoal analysis, to examine the resilience of this ecosystem to drought and fire. Our analysis demonstrates a complex relationship between climate, fire and floristic composition over multi-millennial time scales, and reveals that moisture variability is the dominant control upon community turnover in this ecosystem. Maximum drought during the Early Holocene, consistent with regional drought reconstructions, correlates with a period of significant fire activity between 8000 and 7000 cal yr BP which resulted in a decrease in SDTF diversity. As fire activity declined but severe regional droughts persisted through the Middle Holocene, SDTFs, including Anadenanthera and Astronium, became firmly established in the Bolivian lowlands. The trend of decreasing fire activity during the last two millennia promotes the idea among forest ecologists that SDTFs are threatened by fire. Our analysis shows that the Chiquitano seasonally dry biome has been more resilient to Holocene changes in climate and fire regime than previously assumed, but raises questions over whether this resilience will continue in the future under increased temperatures and drought coupled with a higher frequency anthropogenic fire regime. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
229. A 9600-year record of water table depth, vegetation and fire inferred from a raised peat bog, Prince Edward Island, Canadian Maritimes.
- Author
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Peros, Matthew, Chan, Kathleen, Magnan, Gabriel, Ponsford, Leila, Carroll, James, and McCloskey, Terry
- Subjects
PEAT bogs ,WATER table ,WATER levels ,PALEOCLIMATOLOGY ,HOLOCENE Epoch - Abstract
ABSTRACT A 582-cm-long peat core was collected from Baltic Bog, an ombrotrophic peatland in north-eastern Prince Edward Island, Canada. The core was studied for testate amoebae, plant macrofossils, macrocharcoal, peat humification and organic matter content. The results show that Baltic Bog first developed ∼9600 cal a BP as a minerotrophic peatland (fen) dominated by Cyperaceae. At 8200 cal a BP, the fen transitioned into a peat bog dominated by Sphagnum. Between 8200 and 4000 cal a BP, water table depth (WTD) was generally low and the bog surface supported trees such as Picea mariana. From 4000 to 1700 cal a BP, WTD rose and the bog became more open. The macrocharcoal results show that the period ∼2000-1000 cal a BP was characterized by several fire events that may have occurred on the bog surface at the core site. The results presented in this paper correspond closely with previous fossil pollen research done at Baltic Bog and suggest that regional climate change was a key factor in controlling long-term WTD variability and vegetation change at the site. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
230. Geochemical characteristics of Holocene aeolian deposits and their environmental significance in the Mu Us Desert, northern China.
- Author
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Liu, Bing, Jin, He‐Ling, Sun, Liang‐Ying, Sun, Zhong, Niu, Qing‐He, and Zhang, Cai‐Xia
- Subjects
ERGS (Landforms) ,HOLOCENE Epoch ,SEDIMENTATION & deposition research ,PALEOPEDOLOGY ,WEATHERING ,DESERTS ,METEOROLOGICAL precipitation - Abstract
This paper addresses the surface and Holocene aeolian deposits in the southeastern Mu Us Desert, N. China, systematically analysing the evolution of the geochemical characteristics of aeolian sand-palaeosol sequences and their environmental significance. Our results indicate that the geochemical components of the Holocene aeolian deposits and surface deposits had the similar material sources, sediment transport and deposition processes in the study region, which were dominated by SiO
2 , Al2 O3 , and Na2 O. In the weathering process of the Jinjie (JJ) profile, the Na, K, and Si presented the slight leaching and migration in general, while the other elements were relatively accumulated. The Holocene aeolian deposits and surface deposits incurred weaker geochemical weathering under cold and dry conditions and were only weakly leached, which implies a relatively arid environment in the Holocene epoch and the modern era. The weathering degree was controlled by the regional temperature and precipitation, and was probably more sensitive to the precipitation changes. In the sedimentary profile, the geochemical parameters and migration of elements demonstrated that there have been several alternating warm-wet and cold-dry intervals in the Mu Us Desert in the Holocene epoch; there were relatively warm and wet conditions prior to 4.6 ka, and it has been cold and dry since then. Six millennial-scale dry events were recorded during the Holocene, which were not only accordant with the history of palaeoclimatic changes in the different latitudes and archives of the Northern Hemisphere, but also correspond to the millennial-scale variation of cosmic radiation and solar activity during that period. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]- Published
- 2016
- Full Text
- View/download PDF
231. Mediterranean Holocene climate, environment and human societies.
- Author
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Holmgren, Karin, Gogou, Alexandra., Izdebski, Adam., Luterbacher, Juerg., Sicre, Marie-Alexandrine, and Xoplaki, Elena
- Subjects
- *
SPECIAL issues of periodicals , *PERIODICAL articles , *HOLOCENE Epoch , *GLOBAL environmental change , *SOCIAL change , *PALEOENVIRONMENTAL studies - Abstract
This paper introduces the reader to a special issue of articles that explores links and processes behind societal change, climate change and environmental change in a Holocene perspective in the Mediterranean region. All papers are, by purpose, co-authored by scientists representing different disciplines. The cross-cutting theme has been to reach beyond simple explanations of potential climate-society relationships and advance our understanding on how to improve research methods and theories in the field. The thirteen papers in this issue address these questions in three different ways, by i) conceptual/methodological approaches; ii) review papers; and iii) case studies. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
232. Are pollen records from small sites appropriate for REVEALS model-based quantitative reconstructions of past regional vegetation? An empirical test in southern Sweden.
- Author
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Trondman, Anna-Kari, Gaillard, Marie-José, Sugita, Shinya, Björkman, Leif, Greisman, Annica, Hultberg, Tove, Lagerås, Per, Lindbladh, Matts, and Mazier, Florence
- Subjects
PALYNOLOGY ,VEGETATION boundaries ,MONTE Carlo method ,HOLOCENE Epoch - Abstract
In this paper we test the performance of the Regional Estimates of VEgetation Abundance from Large Sites (REVEALS) model using pollen records from multiple small sites. We use Holocene pollen records from large and small sites in southern Sweden to identify what is/are the most significant variable(s) affecting the REVEALS-based reconstructions, i.e. type of site (lakes and/or bogs), number of sites, site size, site location in relation to vegetation zones, and/or distance between small sites and large sites. To achieve this objective we grouped the small sites according to (i) the two major modern vegetation zones of the study region, and (ii) the distance between the small sites and large lakes, i.e. small sites within 50, 100, 150, or 200 km of the large lakes. The REVEALS-based reconstructions were performed using 24 pollen taxa. Redundancy analysis was performed on the results from all REVEALS-model runs using the groups within (i) and (ii) separately, and on the results from all runs using the groups within (ii) together. The explanatory power and significance of the variables were identified using forward selection and Monte Carlo permutation tests. The results show that (a) although the REVEALS model was designed for pollen data from large lakes, it also performs well with pollen data from multiple small sites in reconstructing the percentage cover of groups of plant taxa (e.g. open land taxa, summer-green trees, evergreen trees) or individual plant taxa; however, in the case of this study area, the reconstruction of the percentage cover of Calluna vulgaris, Cyperaceae, and Betula may be problematic when using small bogs; (b) standard errors of multiple small-site REVEALS estimates will generally be larger than those obtained using pollen records from large lakes, and they will decrease with increasing size of pollen counts and increasing number of small sites; (c) small lakes are better to use than small bogs if the total number of small sites is low; and (d) the size of small sites and the distance between them do not play a major role, but the distance between the small sites and landscape/vegetation boundaries is a determinant factor for the accuracy of the vegetation reconstructions. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
233. Local vegetation dynamics and human habitation from the last interglacial to the early Holocene at Theopetra cave, central Greece: the evidence from wood charcoal analysis.
- Author
-
Ntinou, Maria and Kyparissi-Apostolika, Nina
- Subjects
CHARCOAL analysis (Archaeology) ,VEGETATION dynamics ,INTERGLACIALS ,PLEISTOCENE Epoch ,HOLOCENE Epoch - Abstract
This paper presents the results of wood charcoal analysis carried out on material from Theopetra cave in central Greece. The sequence dates from prior to 130-8 ka bp and is made up of layers of both anthropogenic and geogenic origins. The study of the wood charcoal samples from these layers sets out to distinguish changes in the local vegetation through time, to correlate these with broader environmental conditions and to discuss how they may relate to differences in the frequency and intensity of human occupation of the cave from shortly before the last interglacial to the Holocene. Changes in the presence and frequency of Prunus sp., Juniperus sp. as well as taxa needing temperate, thermophilous or riverine conditions in successive layers reflect a pattern of vegetation succession that can be correlated with the pollen and marine isotope stage (MIS) records. The earliest human occupation took place in an open park-woodland environment dominated by Prunus during the late MIS 6-6/5 transition. This was followed by a succession of temperate woodlands with deciduous Quercus, Carpinus and Fraxinus, reflecting the optimal conditions of the last interglacial (MIS 5e), followed by more open vegetation during subsequent cooling events. Middle Palaeolithic hunter-gatherers visited the cave repeatedly during the last interglacial, in contrast to more sporadic human presence during the following climatic deterioration. This was characterized by Juniperus dominated steppe and open vegetation and/or riparian woods, reflecting the harsh and unstable climatic conditions of the pleniglacial. Finally, the expansion of Pistacia and re-establishment of temperate woodland points to climatic amelioration during the Holocene from which there is evidence of regular use of the cave by Mesolithic and Neolithic people. The dominant role of Prunus observed in several periods provides important complementary information to the pollen evidence from the late Pleistocene. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
234. Pseudonubeculina arabica n. gen. n. sp., a new Holocene benthic foraminifera from the Arabian Gulf.
- Author
-
Amao, Abduljamiu O. and Kaminski, Michael A.
- Subjects
FORAMINIFERA ,RHIZOPODA ,GRAIN ,MILIOLIDAE ,CALCITE - Abstract
This paper describes an enigmatic new agglutinated benthic foraminiferal genus and species that shares some morphological features with the Reophax, Hormosina and Nubeculina groups. Pseudonubeculina arabica n.gen. n.sp. is characterized by its uniserial chamber arrangement, coarsely agglutinated bilamellar testwallwithwhite high-Mg calcite cement, and a terminal slit-like aperture formed by the flat sides of two ormore large agglutinated grains. The new genus cannot be placed within any of the previously described families of the Miliolida. The current classification of the Miliolida does not accommodate a genus with a wholly uniserial chamber arrangement. This species can easily be distinguished by its prominent terminal slit-like aperture, formed using the flat sides of two ormore large agglutinated grains, lined by an imperforate rim of secreted calcite. The species has a restricted area and depth distribution in the Arabian Gulf. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
235. Coastal landforms and the Holocene evolution of the Island of Samsø, Denmark.
- Author
-
Sander, Lasse, Fruergaard, Mikkel, and Pejrup, Morten
- Subjects
COASTAL mapping ,GEOMORPHOLOGICAL mapping ,HOLOCENE Epoch - Abstract
The geomorphology of a coastal landscape may reveal an indication of past shoreline configurations. The spatial arrangement of the preserved morphologies may further contain indications on the importance of the different key parameters influencing shoreline evolution over millennial timescales, such as palaeo sea-level position, longshore currents, energy gradients, and sediment supply. This paper presents the results and observations of a surveying and mapping study conducted for the island of Samsø at a scale of 1:75,000. The objective of the work is to support the interpretation of core sample data and to extract information on the factors determining the morpho-sedimentary development of moraine-embedded coastal lagoon systems during the Holocene. The map is based on an airborne LiDAR-derived high-resolution digital terrain model that is combined with spatial information on bathymetry, surface geology and other features from archived geodata and maps. [ABSTRACT FROM PUBLISHER]
- Published
- 2016
- Full Text
- View/download PDF
236. Radiocarbon Dating and Stable Isotopic Analysis of Insect Chitin from the Rancho La Brea Tar Pits, Southern California.
- Author
-
Holden, A R and Southon, J R
- Subjects
RADIOCARBON dating ,ISOTOPIC analysis ,INSECTS ,CHITIN ,ACCELERATOR mass spectrometry ,ARCHAEOLOGY methodology - Abstract
This paper presents the first successful methods for accelerator mass spectrometry (AMS) dating of asphalt-impregnated insect chitin from the Rancho La Brea Tar Pits in southern California. A persistent problem with stratigraphic correlation at this site is that asphalt flows are characteristically intermittent and are really discontinuous, which can result in mixing fossils of quite different ages. Direct 14C dating of specimens circumvents this difficulty but requires a pretreatment method that can produce dates from relatively small samples (<10 mg) of insect cuticle, while successfully removing residual asphalt and sample preparation solvents as well as soil carbon contamination. 14C dating accuracy was verified by comparing dates on insect chitin with ages for seeds and twigs compacted during a rapid entrapment event within a separately dated skull of the Western Camel, Camelops hesternus Leidy. All dates fell within a relatively narrow range of ~40,000–44,000 14C yr BP, suggesting that such methods can be used with confidence on other insect material from this site. Insects are often superior paleoenvironmental indicators for establishing precise data points for climate fluctuations. This is because their lifecycles and present-day climate-restricted geographic distributions are well documented, and unlike migrating mammals and birds, insects offer crucial information about the local environment. Our results are therefore potentially significant for studies of paleoecological and paleoclimatic change within the Los Angeles Basin and coastal southern California, as well as reconstruction of entrapment events at Rancho La Brea. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
237. Late Pleistocene Bays and Reefs: Ancestors to the Modern Caribbean Coast, Yucatán Península, México.
- Author
-
Shaw, Charles E.
- Subjects
KARST research ,LANDFORMS ,SINKHOLES ,COASTS ,HOLOCENE Epoch - Abstract
Shaw, C.E., 2016. Late Pleistocene bays and reefs: Ancestors to the modern Caribbean coast, Yucatán Península, México. Low-lying indentations along the modern Caribbean coast of the Yucatán Peninsula host shallow bays with classic crescent-shaped, white-sand beaches. These indentations have previously been explained as products of Holocene dissolution of Pleistocene limestones within a brackish coastal mixing zone. This paper demonstrates that the lows confining the modern bays were formed by sedimentary processes 122,000 ± 2000 YBP, during the late Pleistocene. A 50 km stretch of the Caribbean coast between Tankah and Playa del Carmen, here called the high coast, is characterized by rocky headlands that are underlain by fossilized coral reefs of late Pleistocene age and lows between headlands occupied by modern bays. Study of landforms using aerial photographs together with field examination of late Pleistocene calcarenite exposed in quarries has led to recognition of a series of arcuate Pleistocene beaches with large attached spits that developed during a period of falling sea level that followed the oxygen isotope substage 5e sea-level highstand. Pleistocene beaches and associated triangular spits form a series of cuspate arcs, each precisely aligned with one of the modern bays and each triangular spit aligned with the center of a modern headland. This exact and repeated coincidence of substage 5e bays with modern bays and beaches indicates that low areas occupied by modern bays lie within the lowest portions of late Pleistocene bays that were drained during the Wisconsin glacial and reflooded in their lowest parts during the post-Wisconsin rise of sea level in the Holocene. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
238. Evolution of landscapes of the Moskva River floodplain in the Atlantic and Subboreal: Pedological and palynological records.
- Author
-
Ershova, E.G., Alexandrovskiy, A.L., and Krenke, N.A.
- Subjects
- *
LANDSCAPE changes , *FLOODPLAINS , *SOIL science , *PALYNOLOGY - Abstract
Floodplain deposits in the valley of the Moskva River contain a series of buried soils of the Holocene age, which can be an important source of paleoecological information. These soils were dated as follows: Soil 1 — 100 BP, Soil 2 — cal 1200 AD–500 BC, Soil 3 — 900–2700 BC, and Soil 4 — 3700–6000 BC. Archeological monuments associated with these soils belong to the Neolithic (Soil 4), Early Bronze Age (Soil 3), and Iron Age and Middle Ages (Soil 2). Buried soils have well developed profiles and diagnostic features. Dark-colored soils of the Atlantic period (Soil 4) in most cases can be attributed to Phaeozems. Pollen analysis shows that these soils were formed under forest-steppe communities. Buried soils of the Subatlantic period (Soil 2) are usually referred to as Luvisols. Unlike them, the soils of the Subboreal period (Soil 3) are traced in rare cases and have no clear diagnostic features allowing reconstruction of the paleoenvironment. These soils have a light-colored humus horizon, which does not allow them to be classified as Phaeozems. However, they do not have the Bt horizon characteristic of Luvisols. This paper describes the results of a new comprehensive study of the Moskva River floodplain near the Zvenigorod Biological Station (ZBS) of Moscow State University. The buried soils of the Atlantic and Subboreal periods were studied by palaeopedological and palynological methods. The findings confirmed previously obtained results and indicated that the buried Soil 3 at the ZBS site could be developed under mixed forests dominated by spruce. These results suggest that the landscapes of the lower levels of the valley changed dramatically between 5000 and 4500 cal BP. The forest-steppe communities were replaced by dense forests due to the early Subboreal climate change. The paper also examines the specifics of soil and pollen records of the landscape evolution. The anthropogenic influence on the floodplain landscapes is also considered. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
239. Geomorphological & Geoarchaeological Indicators of the Holocene Sea-Level Changes on Ras El Hekma Area, NW Coast of Egypt.
- Author
-
Torab, Magdy
- Subjects
- *
GEOMORPHOLOGY , *ARCHAEOLOGICAL geology , *HOLOCENE Epoch , *SEA level , *SEDIMENTARY rocks - Abstract
Ras El Hekma area is a part of the NW coast of Egypt. It is located on the Egyptian Mediterranean Coast, approximately 220 km West of Alexandria City. It is shaped as a triangle with its headland extending into the Mediterranean sea for about 15 km, and is occupied by sedimentary rocks belonging to the Tertiary and Quaternary Eras. Its western coastline consists of Pleistocene Oolitic limestone ridges with separated steep scarps, while the eastern coastline consists of sandy beaches, coastal spits, coastal bars, tombolos and bays. The objective of this paper is to define some geomorphological and geoarchaelological indicators of The Holocene sea-level changes in the study area, especially the geomorphic landforms such as: marine notches, cliffs, sea caves and benches. This is to add to some archaeological remains that have been discovered by the paper's author under the current sea level. These remains include: submerged ruins of Greek and Roman harbors, wells and fish tanks near the coastline (Leuke Akte, Hermaea, Phoinikous and Zygris), in addition to an ancient Roman harbor used during the World War II in Tell El Zaytun area (Site #6). Evaluations of the discovered archaeological remains help our understanding of the evolution of the sea level during the Holocene. This study is based on observation of the relative sea-level curves drawn of the Holocene, detailed geomorphological and Geoarchaelogical surveying, sampling, dating and mapping as well as satellite image interpretation and GIS techniques. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
240. Association of the Northern Hemisphere circumglobal teleconnection with the Asian summer monsoon during the Holocene in a transient simulation.
- Author
-
Zhang, Xiaojian and Jin, Liya
- Subjects
TELECONNECTIONS (Climatology) ,MONSOONS ,COMPUTER simulation ,OCEAN-atmosphere interaction ,OCEAN temperature - Abstract
This paper provides another look at the response of the Asian summer monsoon (ASM) to insolation forcing and oceanic feedback during the Holocene, using a fully coupled general circulation ocean–atmosphere model forced by Earth’s orbital variations. The model results revealed a recurrent circumglobal teleconnection (CGT) pattern in the summertime (June–July–August) mid-latitude circulation of the Northern Hemisphere during the Holocene. The CGT index showed a decreasing trend before ~5 ka BP and a slight increasing trend afterwards, affected by the combined effects of summer insolation, Indian summer monsoon (ISM), North Atlantic and Indian Ocean–western Pacific Ocean sea surface temperature (SST). The CGT showed a close relationship with ASM precipitation and surface air temperature during the Holocene and, therefore, could act as a bridge linking the ASM to insolation, high-latitude forcing (North Atlantic SST), and low-latitude forcing (tropical Ocean SST). We emphasize that the mid-latitude atmospheric circulation has been a key factor for the evolution of the ASM during the Holocene. In addition, the CGT provides a viable explanation for the out-of-phase relationship in the moisture evolution but an in-phase relationship in the speleothem δ
18 O between arid central Asia and the ISM region during the Holocene. [ABSTRACT FROM AUTHOR]- Published
- 2016
- Full Text
- View/download PDF
241. Another look at tarsometatarsi of early penguins.
- Author
-
Jadwiszczak, Piotr
- Abstract
The tarsometatarsus, a compound bone from the lower leg in birds, is the most important skeletal element in fossil penguin taxonomy, especially in the case of early members of this group. However, any attempt to go beyond the problem of mere classification obviously requires the better understanding of osteological traits under consideration. This in turn touches on the issue of interplay between bone and concomitant soft-tissue structures, such as muscles, tendons and vessels. This paper focuses on the more holistic comprehension of the tarsometatarsal section of the Eocene penguin foot, based on the analysis of the myology and the vascular system of its modern counterparts. A number of graphical reconstructions are provided with a discussion of the role of the hypotarsus and intermetatarsal foramina. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
242. Geochemical evidence for Holocene millennial-scale climatic and environmental changes in the south-eastern Mu Us Desert, northern China.
- Author
-
Liu, Bing, Jin, Heling, Sun, Liangying, Sun, Zhong, and Zhao, Shuang
- Subjects
CLIMATE change ,GLOBAL environmental change ,MONSOONS ,OSCILLATIONS ,DESERTS - Abstract
Deserts and sandylands that are located in the semi-arid and arid regions in the middle latitudes of the Northern Hemisphere are usually regarded as environmentally sensitive change belts which respond to global climatic change. In northern China, activation or immobilization of sand dunes is mainly influenced by humid and dry variation and is related to stronger or weaker Asian monsoons. In this paper, the history of Holocene millennial-scale climatic and environmental change is reconstructed by the systematic analysis of the geochemical element contents and parameters, along with the OSL and C chronologies, from the different lithologies of the palaeosol-aeolian sand sequence in the south-eastern Mu Us Desert, northern China. Our results indicate that the region was dominated by a dry climate with intensive aeolian activity before 7.2 ka BP, and there was an optimal humid climate and fixed desert in 7.2-4.6 ka. Afterwards, the dune fields became mobile again as the effective humidity declined. Additionally, six dry events were discovered with times of ~7.2, 7.0-6.8, 6.6-5.7, 4.6-4.1, 3.7-3.5, and 3.3-2.5 ka, which were not only coincident with the intervals of millennial-scale weaker Asian summer monsoons, but also accordant with the cold events evidenced in the ice cores and deep-sea deposits of the high latitudes in the Northern Hemisphere. In general, the Holocene climatic and environmental changes had the characteristics of the 'monsoonal mode' and 'abrupt millennial-scale oscillation' in the Mu Us Desert. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
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243. Early and Middle Holocene Human Occupation of the Egyptian Eastern Desert: Sodmein Cave.
- Author
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Vermeersch, Pierre, Linseele, Veerle, Marinova, Elena, Neer, Wim, Moeyersons, Jan, and Rethemeyer, Janet
- Subjects
PREHISTORIC settlements ,NEOLITHIC Period ,HOLOCENE Epoch ,HERDING ,ARCHAEOLOGICAL dating - Abstract
Copyright of African Archaeological Review is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2015
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244. Late-Holocene record of lagoon evolution, climate change, and hurricane activity from southeastern Cuba.
- Author
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Peros, Matthew, Gregory, Braden, Matos, Felipe, Reinhardt, Eduard, and Desloges, Joseph
- Subjects
LAGOONS ,CLIMATE change ,PALEOENVIRONMENTAL studies ,SEA level ,FORAMINIFERA ,FOSSIL pollen ,ACCELERATOR mass spectrometry - Abstract
A sediment core from a lagoon in southeastern Cuba was the focus of a multi-proxy paleoenvironmental study to investigate lagoon response to sea-level change and climate change and also to infer changes in the frequency of past hurricane strikes. The proxy data examined included benthic foraminifera, fossil pollen, particle size analysis, and macrocharcoal influx values. The core was dated using
137 Cs and accelerator mass spectrometry (AMS) radiocarbon methods. The results show that lagoon formation began approximately 4000 years ago and that the lagoon environment evolved through four phases: (1) from ~4000 to 2800 cal. yr BP, the lagoon was a shallow polyhaline to euryhaline system with limited mangrove coverage; (2) from ~2800 to 2000 cal. yr BP, there was a decrease in salinity which facilitated the expansion of red mangrove; (3) from ~2000 to 1000 cal. yr BP, sea-level rise resulted in an increase in water depth and possibly salinity; and (4) from ~1000 cal. yr BP to the present, water level continued to rise and the mangrove environment diversified. The shift to lower salinity conditions from ~2800 to 2000 cal. yr BP may have been climate driven as similar changes are seen at lagoons elsewhere in Cuba. The particle size data show several periods where sand-sized particles are more abundant; these periods are similar to data from Puerto Rico that document times of relatively frequent hurricanes. This paper shows that coastal lagoons are useful archives of paleoclimatic and paleoenvironmental information in the Caribbean region and that they should be the focus of additional research efforts. [ABSTRACT FROM AUTHOR]- Published
- 2015
- Full Text
- View/download PDF
245. Environmental imprints of landscape evolution and human activities during the Holocene in a small catchment of the Calanques Massif (Cassis, southern France).
- Author
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Romey, Carole, Vella, Claude, Rochette, Pierre, Andrieu-Ponel, Valérie, Magnin, Fréderic, Veron, Alain, Talon, Brigitte, Landuré, Corinne, D’Ovidio, Anne-Marie, Delanghe, Doriane, Ghilardi, Matthieu, and Angeletti, Bernard
- Subjects
WATERSHEDS ,ALLUVIAL plains ,EFFECT of human beings on climate change ,BIOMARKERS ,FUNGAL spores ,HOLOCENE Epoch - Abstract
This paper is based on a multidisciplinary study using both paleoenvironmental methods (biological, sedimentological, magnetic and geochemical) and archaeological data in order to characterize landscape and hydrological network changes as well as human impact on a littoral catchment in the Western Mediterranean area. Sedimentary records obtained around a coastal alluvial plain (Cassis, Southeastern France) reveal local environmental changes and human activities since the Neolithic (ca. 6000 cal. BP). Anthropogenic impact is already noticeable in the earliest record, and we follow its evolution through time. According to biological markers, the Holocene landscape of the Calanques is dominated by a mosaic of open herbaceous formations partly generated by human activity. The prevalence of Cernuella virgata in malacofauna successions and of coprophilous fungal spores in the pollen record testifies to the spread of agro-pastoral activities. Two increases of anthropogenic impact are highlighted during the Roman (ca. 2000 cal. BP) and Modern (from ca. 1450 to today) periods. Lead isotope analyses indicate an anthropogenic release of lead, possibly originating from the Greek Cyclades (ca. 2000 cal. BP). Hydrographic and agricultural work is also enhanced during the Roman period. Magnetic parameters and lead isotopes indicate that the Modern anthropogenic impact may be associated with high temperature activities (e.g. lime kiln, fossil fuel). [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
246. A Holocene East Asian winter monsoon record at the southern edge of the Gobi Desert and its comparison with a transient simulation.
- Author
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Li, Yu and Morrill, Carrie
- Subjects
HOLOCENE Epoch ,MADDEN-Julian oscillation ,MONSOONS ,COMPARATIVE studies ,SEDIMENTS - Abstract
The East Asian winter monsoon (EAWM) exhibits significant variability on intraseasonal, interannual, and interdecadal time scales and the variability can be extended to Holocene centennial and millennial scales. Previous Holocene EAWM proxy data records, which were mostly located in Central, Eastern and Southern China, did not show a consistent Holocene EAWM history. Therefore, it is difficult to provide insights into mechanisms of the long-term winter monsoon variability on the basis of the records. Eolian sediments at the southern edge of the Gobi Desert, Western China, are sensitive to the EAWM changes and less affected by the East Asian summer monsoon due to an obstruction of the Qinghai-Tibet Plateau. This paper presents a comparison between a well-dated Holocene EAWM record and coupled climate model simulations, so as to explore physical processes and influencing factors of the Holocene EAWM. Sediment samples from two Holocene eolian sedimentary sections [Huangyanghe (a) and Huangyanghe (b)] were acquired at the southern edge of the Gobi Desert. Chronologies were established based on twenty bulk organic matter AMS C ages and five pollen concentrates AMS C ages. Proxy data, including grain-size, total organic carbon, magnetic susceptibility and carbonate content were obtained from the two eolian sections. The grain-size standard deviation model was applied to determine components sensitive to variability of the Holocene EAWM. After a comparison of environmentally-sensitive grain-size components and proxy data, the 20-200 μm component at the Huangyanghe (a) and the 20-159 μm component at the Huangyanghe (b) section were selected as indicators of the Holocene EAWM, which show a strong early Holocene winter monsoon and a decline of the winter monsoon since the mid-Holocene. We also present equilibrium and transient simulations of the climate evolution for the Holocene using a state-of-art coupled climate model: the Community Climate System Model version 3 (CCSM3). Indices for the Holocene EAWM were calculated and are consistent with the reconstructed Holocene EAWM intensity. The simulations indicate that orbital forcing effects on the land-sea temperature and sea level pressure contrast can account for the observed EAWM trends. Other forcings that were present in the early Holocene, including the remnant Laurentide ice sheet and meltwater forcing in the North Atlantic, were not responsible for the Holocene trends. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
247. Temporal changes in proportions of small mammals in the diet of the mammalian and avian predators in Slovakia.
- Author
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OBUCH, Ján
- Subjects
- *
MAMMALS , *PREDATORY animals , *CARNIVOROUS animals , *BRANDT'S vole , *GLOBAL environmental change - Abstract
The paper presents a brief account of the temporal changes found in proportions of the mammal components in the diets of several species of predators (owls and carnivores) collected from various sites in Slovakia and originating in various periods (Late Pleistocene–Recent). The material collected from the Šarkanica Cave (Muráňska planina Mts.) contained bones in three layers, dated using the radiocarbon analysis (14 C) to 18,000–21,000 years BP (18–21 Ka), showing relatively small differences in composition of the fossil diet of Bubo scandiacus with predominance of Lasiopodomys gregalis (73.3%) and Chio- nomys nivalis (6.9%). A similar type of material from the Nový 3 Cave (Belianske Tatry Mts.), dated to the period of 30 Ka, contained more numerous remnants of Lemmus cf. lemmus and Sorex tundrensis. Undated samples from the Nový 1 Cave and from the Šarkania diera Cave (Súľovské skaly Mts.), which differ in their higher abundance of Dicrostonyx cf. gulielmi, are probably dated from the colder period of the last glacial maximum. Three samples from caves in the Veľká Fatra Mts. dated from the Late Pleisto- cene (Upper Dryas) originated from carnivores, with differences in relative proportions of predominant prey species: Chionomys nivalis (80.0%) and Lasiopodomys gregalis (14.3%), while remains of Cricetus cricetus (0.6%) also appear there. Two examples of differences in the diet composition of Strix aluco in the Veľká Fatra Mts. are present in samples dated to the Holocene period: natural development of forest fauna in the environs of Dolný Harmanec and anthropogenic influence in the form of three deforestation periods in the Tlstá massif near Blatnica (both Veľká Fatra Mts.). A sample set of the diet of Tyto alba dated >500 years BP from a church in Žilina is compared with a recent sample set of this owl diet from the Turčianska kotlina Basin and from the Danubian Lowland (Tekovské Lužany). The main difference lies in the greater proportion of the murid rodents and the relatively lower abundance of Microtus arvalis in the sample from the 16th century. Similar results were found comparing samples of Tyto alba diet, taken from a cave near Hatiny (Slovenský kras Mts.) and expected to be 100 years old, with more recent samples from the Košická kotlina Basin. The collection from the Hatiny Cave differs from the recent material in the presence of Sicista trizona and Alexandromys oeconomus. The recent samples of the diet of Bubo bubo taken from the Horné Považie Basin differ from the samples dated back more than 70 years ago by a high proportion of the genus Apodemus and a predominant incidence of frogs, while the old samples come from the period of the communist influence of the agricultural production causing serious environmental changes in the countryside (1950s) and as a result, a greater volume of large prey species, Rattus norvegicus, Arvicola amphibius, Lepus europaeus, and Erinaceus roumanicus. Since 1990, the availability of large prey for Bubo bubo has decreased due to the decline of livestock farming and a con- sequent successional overgrowing of pasture land by trees. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
248. Potential parasitic infections transmitted by seafood in ancient populations from Patagonia.
- Author
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Alarcos, A.J. and Suby, J.A.
- Subjects
- *
PARASITIC diseases , *FOODBORNE diseases , *MARINE mammals , *MAMMAL populations , *ARCHAEOLOGICAL excavations , *MARINE fishes , *POPULATION , *ZOONOSES - Abstract
Several foodborne diseases have been described in coastal populations from the past, many of them including parasitic infections related to marine diets. Considering this background, the strong relationship between hunter-gatherers from Patagonia and the marine species implies a possible source of parasitic infections and zoonotic risk. However, marine parasitic species have not been identified in archaeological sites from Patagonia so far. The aim of this paper is to propose the potential parasitic infections produced by the consumption of marine molluscs, fishes, birds and sea mammals by human populations from Patagonia during the Holocene, considering the current parasitic species identified in the Southern Atlantic Ocean. We searched in journal articles and book chapters for references of archaeological remains of molluscs, fishes, seabirds and marine mammals recorded in archaeological sites from the Atlantic coast below the 42nd parallel South. Afterwards, we surveyed all the macroparasites of marine origin identified by current parasitological research in the same species found in the archaeological record. We found that most of the marine species in the zooarchaeological record of Patagonia are currently hosts of many parasites. Some species of molluscs, fishes and pinnipeds are highly infected by larvae that are potentially hazardous for human health. Some of them are responsible for acute or chronic zoonotic diseases, with severe consequences depending on how the food was cooked, the amount of consumed parasites and the immune response of the host, in this case, humans. Fishes are host of several parasites related to anisakidosis and corynosomiasis. Sea lions species were also a potential source of the same zoonosis but also diphyllobothriasis. Molluscs are hosts of several parasitic species, but with less severe consequences for human health. On the other hand, birds are infected by adult parasites, without direct zoonotic importance. These findings, although limited by temporal and environmental variability, can provide a speculative overview about the potential influence of marine diets in the health of past hunter-gatherers of Patagonia, particularly if fishes, molluscs or marine mammals were consumed inadequately cooked. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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- View/download PDF
249. Evaluating human responses to ENSO driven climate change during the Holocene in northwest Australia through macrobotanical analyses.
- Author
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Dilkes-Hall, India Ella, Balme, Jane, O'Connor, Sue, and Dotte-Sarout, Emilie
- Subjects
- *
HOLOCENE Epoch , *CLIMATE change , *ABORIGINAL Australians , *SOUTHERN oscillation , *ARCHAEOLOGICAL excavations ,EL Nino - Abstract
The Holocene is recognised as a period through which a number of climatic fluctuations and environmental stresses occur—associated with intensifying El Niño–Southern Oscillation (ENSO) climatic conditions from c. 5000 years—contemporaneous with technological and social changes in Australian Aboriginal lifeways. In the Kimberley region of northwest Western Australia, human responses to ENSO driven climate change are most evident archaeologically in technological transformations observed in lithic records, with little research on changes in plant use during this time. Using nine archaeological sites across the Kimberley, this paper synthesises previously published macrobotanical data (Carpenter's Gap 1, Moonggaroonggoo, Mount Behn, and Riwi), reports unpublished data (Brooking Gorge 1, Djuru, and Wandjina rockshelter), and presents results of sites reanalysed for this study (Widgingarri Shelters 1 and 2) to develop a picture of localised and regional patterns of plant use during the Holocene. We conclude that food plants associated with monsoon rainforest environments dominate both mid- and late Holocene macrobotanical records and, although monsoon rainforest likely retreated to some extent because of decreased precipitation during the late Holocene, no human responses associated with ENSO driven climate change occurred in relation to human uses of plants. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
250. Assessing the spread and uptake of tula adze technology in the late Holocene across the Southern Kimberley of Western Australia.
- Author
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Maloney, Tim Ryan and Dilkes-Hall, India Ella
- Subjects
HOLOCENE Epoch ,WOODWORK ,ARCHAEOLOGICAL excavations ,ARCHAEOLOGY ,ANALYSIS of stone implements - Abstract
One of Indigenous Australia's unique stone tools, the tula adze is traditionally viewed as a hafted woodworking tool of the arid zone. Unlike most stone tools in Australia and around the world, the spread and adoption of the tula adze has been described as rapid and instantaneous. The conditions which underlie this technological change are critically assessed in this study, using risk minimisation and diffusion models. The focus of the paper is a study area with unclear tula distribution—the southern Kimberley of Western Australia. The spatial distribution of these tools is reviewed and new discoveries outlined. Reduction sequences and morphological trends observed elsewhere are examined, and compared to the Kimberley record. Some of the archaeological sites analysed also preserve evidence of woodworking activities, such as wood shavings and wooden tools. We use these records, augmented by the association of hardwood species from macrobotanical records, to associate tulas with hardwood species availability in the late Holocene archaeological record of the Kimberley. We conclude that woodworking craft production proliferated in the late Holocene, as a likely result of both diffusion of information and foraging risk minimisation. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
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