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Browsing by Author "Atahan, P"

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Agriculture and environmental change at Qingpu, Yangtze delta region, China: a biomarker, stable isotope and palynological approach
(SAGE Publications, 2007-05) Atahan, P; Grice, K; Dodson, JR
Rice (Oryza sp.) agriculture sustains vast numbers of people and, despite great advancements made in recent years, questions about its origins and spread throughout Asia remain unanswered. This study uses sedimentary biomarker, stable carbon isotope and palynological analyses to investigate early rice agriculture in the Yangtze delta, a region where rice agriculture emerged at least 7000 years ago. Accelerator mass spectrometer (AMS) C-14 dating reveals the age of sedimentary section to be between c. 6000 and 1800 cal. BP. Widespread clearing of forest vegetation c. 2400 cal. BP, is the earliest major human influence detected in the Qingpu record. Following this, rice agriculture probably dominated the Qingpu area. Evidence supporting rice agriculture after c. 2400cal. BP is provided by increased Poaceae and Cereal-type taxa, which occur with high concentrations of plant wax n-alkanes with a dominant C-3 plant origin (C-27-C-31 with odd/even preference, delta C-13 -29.8 parts per thousand to -36.3 parts per thousand). Also, high concentrations of a C-20 highly branched isoprenoid (HBI) thought to be from epiphytic algae associated with rice agriculture occur after c. 2400cal. BP. C-13-depleted diploptene (in high concentrations) and C-13-depleted C-31 3b-methylhopanes of methanotrophic bacterial origin also occur after c. 2400cal. BP. The strong methane cycle detected in the trench sediment may have provided an alternative CO2 source for plants and algae associated with rice agriculture. © 2007, SAGE Publications
Climate instability during the last deglaciation in central Asia, reconstructed by pollen data from Yili Valley, NW China
(Elsevier Science BV, 2013-02-15) Zhao, KL; Li, XQ; Dodson, JR; Zhou, XY; Atahan, P
An extended pollen record with grain size analysis and AMS C-14 dating is provided for a palaeolake section which is located in an intermountain basin in Yili Valley, Xinjiang, NW China. Covering the late MIS 3, early MIS 2 and the last deglaciation, vegetation variations and climate events are discussed in relation to changes in pollen assemblages and Artemisia/Chenopodiaceae (A/C) ratios. The presence of montane forest-steppe dominated by Picea and Taraxacum indicates a relative humid climate in the study area during late MIS 3 (before 31.5 cal kyr BP). Picea forest disappeared and the vegetation dominated by Chenopodiaceae shows the climate became dry from 31.5 to 14.7 cal kyr BP. The sediments of Last Glacial Maximum (LGM) period are absent in the section probably. Betula-Picea mixed forest occurred at 14.7 cal kyr BP and corresponds to the onset of the warm Bolling period in the North Atlantic. A long dry period was detected from 14.5 to 13.6 cal kyr BP on the basis of the occurrence of Chenopodiaceae desert. A subalpine meadow community dominated by Geranium covered the area during 13.6-13.4 cal kyr BP, suggesting lower temperatures at this time. This may coincide with the Older Dryas (OD). The most humid period in the record occurred between 13.4 and 12.9 cal kyr BP, which coincides with the warm Allerod period. Dry conditions prevailed from similar to 12.9 to 11.7 cal kyr BP in the area, coinciding with the Younger Dryas (YD) in the North Atlantic. Within this period a three-phase climate fluctuation was detected, which can be summarized as follows: a dry early YD (12.9-12.6 cal kyr BP), a slightly moister mid-YD (12.6-12.0 cal kyr BP) and a very dry late YD (12.0-11.7 cal kyr BP). These millennial to century-scale climatic events in Yili Valley correlate well with other palaeoclimate records in North Hemisphere, suggesting that these events probably originate from same mechanisms. © 2013, Elsevier Ltd.
Climatic variations over the last 4000 cal yr BP in the western margin of the Tarim Basin, Xinjiang, reconstructed from pollen data
(Elsevier, 2012-03-01) Zhao, K; Li, XQ; Dodson, JR; Atahan, P; Zhou, XY; Bertuch, F
The nature of Holocene climate patterns and mechanisms in central Asia are open areas of inquiry. In this study, regional vegetation and climate dynamics over the last ca. 4000 years are reconstructed using a high resolution pollen record from the Kashgar oasis, on the western margin of the Tarim Basin, central Asia. Ephedra, Chenopodiaceae and Cannabaceae dominate the pollen assemblages, and Chenopodiaceae/Ephedra ratios and percentages of long-distance transported pollen taxa are used to infer regional variations in moisture and vegetation density. Three periods of increased humidity are identified, from ca. 4000–2620 cal yr BP, ca. 1750–1260 cal yr BP and ca. 550–390 cal yr BP and these periods coincide with the respective Holocene Bond Events 2, 1 and 0, which are reported in the North Atlantic. Any increase in strength, or southward migration, of the mid-latitude westerlies would result in more precipitation and meltwater on mountains surrounding the study site. Warm and dry conditions are detected between ca.1260 and 840 cal yr BP (AD 690–1110), and cool and wet conditions are detected between ca. 840 and 680 cal yr BP (AD 1110–1270), during the Medieval Warm Period (ca. AD 800–1200). The climate variations in the Kashgar region over the last 4000 years appear to have been dominated by changes to the westerly circulation system and glacier dynamics on surrounding mountains. However, the question of whether the Asian monsoon delivers precipitation to the western Tarim Basin, a region that is influenced by several climate systems, is still open to debate. © 2012 Elsevier B.V.
Diatom community response to climate variability over the past 37,000 years in the sub-tropics of the Southern Hemisphere
(Elsevier Science BV, 2014-01-15) Hembrow, SC; Taffs, K H; Atahan, P; Parr, J; Zawadzki, A; Heijnis, H
Climate change is impacting global surface water resources, increasing the need for a deeper understanding of the interaction between climate and biological diversity. This is particularly the case in the Southern Hemisphere sub-tropics, where little information exists on the aquatic biota response to climate variations. Palaeolimnological techniques, in particular the use of diatoms, are well established and can significantly contribute to the understanding of climatic variability and the impacts that change in climate have on aquatic ecosystems. A sediment core from Lake McKenzie, Fraser Island (Australia), was used to investigate interactions between climate influences and aquatic ecosystems. This study utilises a combination of proxies including biological (diatom), geochemical and chronological techniques to investigate long-term aquatic changes within the perched-dune lake. A combination of Pb-210 and AMS C-14 dates showed that the retrieved sediment represented a history of ca. 37,000 cal. yBP. The sedimentation rate in Lake McKenzie is very low, ranging on average from 0.11 mm to 0.26 mm per year. A sediment hiatus was observed between ca. 18,300 and 14,000 cal. yBP suggesting a period of dry conditions at the site. The diatom record shows little variability over the period of record, with benthic, freshwater acidic tolerant species dominating. Relative abundance of planktonic species and geochemical results indicates a period of increased water depth and lake productivity in the early Holocene and a gradual decrease in effective precipitation throughout the Holocene. Results from this study not only support earlier work conducted on Fraser Island using pollen reconstructions but also demonstrate that diatom community diversity has been relatively consistent throughout the Holocene and late Pleistocene with only minor cyclical fluctuation evident. This record is consistent with the few other aquatic palaeoecological records from the Southern Hemisphere sub-tropics. © 2014, Elsevier Ltd.
Early Neolithic diets at Baijia, Wei River valley, China: Stable carbon and nitrogen isotope analysis of human and faunal remains
(Past Global Changes, 2013-02-13) Atahan, P; Dodson, JR; Li, XQ; Zhou, XY; Hu, S; Chen, L; Bertuch, F; Grice, K
The first farmers of the Wei River valley belonged to the Laoguantai period (ca. 8500-7000 yr BP) and lived in small settlements that were sparsely distributed in the landscape. Understanding of Laoguantai farming practices is limited as only a small number of archaeological sites are known. Here we present stable carbon and nitrogen isotope values for faunal and human bone collagen from Baijia, a Laoguantai site in the Wei River valley of Shaanxi Province, China. Five of the collagen samples have been AMS 14C dated and have a calibrated age range of ca. 7659-7339 yr BP. Stable isotope results show millet and aquatic foods, such as fish and shellfish, being included in the human diet. Bovid samples, which are tentatively identified as water buffalo, have stable carbon isotope values reflecting some millet consumption. The question of whether these bovids were grazing on millet growing wild, or had diets directly influenced by humans, remains to be answered. Stable isotope results for a single pig reveal a markedly different diet, one dominated by C3 plants which would have dominated natural vegetation of the region. Overall, stable isotope results conform to the current view of Laoguantai people being millet farmers with subsistence strategies that included hunted wild foods.
Environmental and cultural changes during the terminal Neolithic: Qingpu, Yangtze delta, eastern China
(SAGE Publications, 2007-11) Itzstein-Davey, F; Atahan, P; Dodson, JR; Taylor, D; Zheng, HB
The lower Yangtze, eastern China, was colonized by several Neolithic and Bronze Age cultures giving rise to possibly the highest concentration of prehistoric sites in the world. Early Neolithic cultures in the delta region cultivated rice (Oryza sativa) and agricultural developments appear to have occurred throughout the Neolithic with abrupt socio-economic changes possibly associated with the terminal Neolithic. Given the extensive history of environmental exploitation and well-preserved archaeological sites, the Yangtze delta is an ideal setting to explore the complex interactions between humans and their environment. Multiproxies of environmental changes, namely pollen, charcoal and phytoliths, in a C-14 AMS-dated sequence of sediments from an exposed profile at Qingpu, Yangtze delta, were investigated. C-14 AMS dating indicates that the age range of the sedimentary sequence analysed is from c. 1800 to 6000 BP, and therefore encompasses the terminal Neolithic and subsequent Bronze Age in the region. This paper reviews this sediment-based evidence in the light of current understanding of human-environment interactions during a critical phase of the development of the Yangtze delta and associated human cultures. © 2007, SAGE Publications
Glacial and Holocene terrestrial temperature variability in subtropical east Australia as inferred from branched GDGT distributions in a sediment core from Lake McKenzie.
(Elsevier Inc., 2014-07-01) Woltering, M; Atahan, P; Grice, K; Heijnis, H; Taffs, K; Dodson, JR
Branched glycerol dialkyl glycerol tetraether (GDGT) distributions observed in a sediment core from Lake McKenzie were utilized to quantitatively reconstruct the pattern of mean annual air temperature (MAAT) from coastal subtropical eastern Australia between 37 and 18.3 cal ka BP and 14.0 cal ka BP to present. Both the reconstructed trend and amplitude of MAAT changes from the top of the sediment core were nearly identical to a local instrumental MAAT record from Fraser Island, providing confidence that in this sediment core branched GDGTs could be used to produce a quantitative record of past MAAT. The reconstructed trend of MAAT during 37 to 183 cal ka BP and timing of the Last Glacial Maximum (LGM) in the Lake McKenzie record were in agreement with previously published nearby marine climate records. The amplitude of lower-than-present MAAT during the LGM potentially provides information on the latitude of separation of the Tasman Front from the East Australian current in the subtropical western Pacific. The Lake McKenzie record shows an earlier onset of near modern day warm temperatures in the early Holocene compared to marine records and the presence of a warmer than present day period during the mid-Holocene. © 2014, Elsevier Inc.
Holocene-aged sedimentary records of environmental changes and early agriculture in the lower Yangtze, China
(Elsevier, 2008-03) Atahan, P; Itzstein-Davey, F; Taylor, D; Dodson, JR; Qin, J; Zheng, HB; Brooks, A
Sedimentary evidence from a total of 21 AMS C-14 dates and 192 pollen and charcoal and 181 phytolith samples from three study sites in the archaeologically rich lower Yangtze in China provides an indication of interactions between early agriculturalists and generally highly dynamic environmental conditions. Results suggest that environmental changes influenced agricultural development, and attest the localised environmental impacts of incipient agriculture. Evidence of human activity, in the form of indicators of deforestation and possibly food production, is apparent by ca 7000 BP (early Neolithic or Majiabang). Clearer evidence of human activity dates to ca 4700 BP (late Neolithic or Liangzhu). Extensive, profound and apparently widespread human impacts do not appear until the Eastern Zhou (Iron Age, ca 2800-2200 BP), however, which in the lower Yangtze was a period associated with technological advances in agriculture, increased urbanisation and relatively stable hydro-geomorphological conditions. © 2008, Elsevier Ltd.
ITRAX core scanner capabilities combined with other geochemical and radiochemical techniques to evaluate environmental changes in a local catchment, South Sydney, NSW, Australia
(Springer, 2015-07-22) Gadd, PS; Heijnis, H; Chagué-Goff, C; Zawadzki, A; Fierro, D; Atahan, P; Croudace, IW; Goralewski, J
In this study, geochemical and radioanalytical techniques are used together with the ITRAX core scanner to reconstruct the environmental history of Mill Creek catchment, located on the south-western fringes of Sydney. This ITRAX capability study was undertaken to investigate environmental changes in a local catchment which incorporates a nuclear research reactor, a small legacy nuclear waste burial ground, extensive new housing developments, a large rubbish tip, as well as quarries. This catchment changed from being near pristine in the 1950’s to an extensively developed catchment with wide ranging land uses. This rapid development has led to silting up near the mouth of the creek, and there is also evidence of periodic siltation triggered by catchment disturbance from local bushfires, associated with peaks in magnetic susceptibility. The sedimentary environment changed from a creek system to a mangrove swamp and saltmarsh. Changes in Cu, Zn and Pb distributions over the last 60 years suggest an anthropogenically-driven input, although concentrations measured by WD-XRF indicate that the level of urbanisation is lower in the study area than in many of the more industrialised and urbanised neighbouring catchments of Sydney estuary and Botany Bay. The activities of 239 + 240Pu and 241Am in the sediment are below detection limit, which strongly suggests that the legacy nuclear waste has not entered the creek system. © 2015, Springer.
Late quaternary environmental change at Lake McKenzie, in subtropical eastern Australia: evidence from sedimentary carbon, nitrogen and biomarkers
(Past Global Changes, 2013-02-13) Atahan, P; Heijnis, H; Le Métayer, P; Grice, K; Taffs, K; Hembrow, SC; Dodson, JR
Fraser Island is part of a large sand mass that extends along the subtropical coastline of south-eastern Queensland. The island is a World Heritage site, listed for its unique natural environment that includes numerous perched oligotrophic dune lakes and a diverse suite of coastal and subtropical vegetation communities. Here we present geochemical and microfossil information for a sediment core collected from Lake McKenzie, in the island’s centre. AMS 14C and 210Pb dating has been conducted and indicates a basal age of ca. 37,000 cal. BP. A hiatus in the sedimentary record is apparent at around 25 cm depth and spans the time period from ca. 18,280 to 13,990 cal yr BP. Elemental and stable isotope measurements of carbon and nitrogen in bulk organic matter, along with biomarker and compound specific carbon isotope analyses, show a clear shift in lake conditions appearing with the re-commencement of sediment accumulation following this hiatus. A marked decline in the abundance of microfossils of the green colonial algae Botryococcus, coincides with a distinct change in composition of Botryococcus derived lipids and a shift to more negative δ13C values of long chain odd n-alkane compounds. An increase in lake size around 13,990 cal yr BP is suggested by the recommencement of sediment accumulation at the site, and is presumably in response to increased effective precipitation. The lake McKenzie record provides a long-term perspective on changing environmental conditions in central Fraser Island.
Late quaternary environmental change at Lake McKenzie, Southeast Queensland: evidence from microfossils, biomarkers and stable isotope analysis
(University of Western Australia, 2013-07-10) Atahan, P; Heijnis, H; Dodson, JR; Grice, K; Le Métayer, P; Taffs, K; Hembrow, SC; Woltering, M; Zawadzki, A
Unravelling links between climate change and vegetation response during the Quaternary is a research priority, and needed if the climate-environment interactions of modern systems are to be fully understood. Using a sediment core from Lake McKenzie, Fraser Island, we reconstruct changes in the lake ecosystem and surrounding vegetation over the last ca. 36.9 cal kyr BP. Evidence is drawn from multiple sources, including pollen, micro-charcoal, biomarker and stable isotope (C and N) analyses, and is used to improve understanding about the timing and spatial scale of past changes that have occurred locally and in the southeast Queensland region. The glacial period of the record, from ca. 36.9-18.3 cal kyr BP, is characterised by lower lake water levels and increased abundance of, or closer proximity to, plants of the aquatic and littoral zone. High abundance of biomarkers and microfossils of the colonial green alga Botryococcus occur at this time and include high variation in individual botryococcene 13C values. A distinct period of dry or ephemeral conditions at the site is detected during deglaciation, causing a hiatus in the sedimentary record covering the time period from ca. 18.3-14.0 cal kyr BP. The recommencement of sediment accumulation around 14.0 cal kyr BP occurs with evidence of lower fire activity in the area and reduced abundance of terrestrial herbs in the surrounding sclerophyll vegetation. The Lake McKenzie record conforms to existing records from Fraser Island by containing evidence for a mid-Holocene dry period, spanning the time period from ca. 6.1-2.5 cal kyr BP. © The Authors
Millet agriculture in north-central China: evidence from human remains
(Australasian Quaternary Association, 2010-07-16) Atahan, P; Dodson, JR; Li, XQ; Zhou, XY; Chen, L; Grice, K
Not available - Powerpoint slides only.
Neolithic agriculture, freshwater resources and rapid environmental changes on the lower Yangtze, China
(Elsevier, 2011-01) Qin, J; Taylor, D; Atahan, P; Zhang, X; Wu, G; Dodson, JR; Zheng, H; Itzstein-Davey, F
Analyses of sedimentary evidence in the form of spores, pollen, freshwater algae, dinoflagellate cysts, phytoliths and charcoal from AMS 14C-dated, Holocene-aged sequences provide an excellent opportunity to examine the responses of Neolithic agriculturalists in the lower Yangtze to changing environments. Evidence from two sites close to the southern margin of the Yangtze delta and separated by what is now Hangzhou Bay attests the critical importance to early attempts at food production of access to freshwater resources. More readily, if episodically, available freshwater resources during the early to mid-Holocene on the Hangjiahu plain may have encouraged an early reliance on rice-based agriculture, which in turn facilitated the accumulation of agricultural surpluses and cultural diversification. Cultural change was relatively attenuated and human population pressures possibly lower on the Ningshao plain, seemingly because of much more profound environmental impacts of variations in local hydrological conditions, and because predominantly saline conditions, associated with rising relative sea level, hampered the early development of irrigated agriculture. The evidence, although largely dating to the early and middle parts of the Holocene, provides a timely warning of the complexity of vulnerability to climate change-induced processes of agriculture, and indeed human activities more generally, on megadeltas in Asia. Analyses of sedimentary evidence in the form of spores, pollen, freshwater algae, dinoflagellate cysts, phytoliths and charcoal from AMS 14C-dated, Holocene-aged sequences provide an excellent opportunity to examine the responses of Neolithic agriculturalists in the lower Yangtze to changing environments. Evidence from two sites close to the southern margin of the Yangtze delta and separated by what is now Hangzhou Bay attests the critical importance to early attempts at food production of access to freshwater resources. More readily, if episodically, available freshwater resources during the early to mid-Holocene on the Hangjiahu plain may have encouraged an early reliance on rice-based agriculture, which in turn facilitated the accumulation of agricultural surpluses and cultural diversification. Cultural change was relatively attenuated and human population pressures possibly lower on the Ningshao plain, seemingly because of much more profound environmental impacts of variations in local hydrological conditions, and because predominantly saline conditions, associated with rising relative sea level, hampered the early development of irrigated agriculture. The evidence, although largely dating to the early and middle parts of the Holocene, provides a timely warning of the complexity of vulnerability to climate change-induced processes of agriculture, and indeed human activities more generally, on megadeltas in Asia. © 2011, Elsevier Ltd.
New insights into the origin of perylene in geological samples.
(Elsevier, 2009-11-01) Grice, K; Lu, H; Atahan, P; Asif, M; Hallmann, C; Greenwood, P; Maslen, E; Tulipani, S; Williford, K; Dodson, JR
The origin of the polycyclic aromatic hydrocarbon (PAH) perylene in sediments and petroleum has been a matter of continued debate. Reported to occur in Phanerozoic organic matter (OM), fossil crinoids and tropical termite mounds, its mechanism of formation remains unclear. While a combustion source can be excluded, structural similarities to perylene quinone-like components present in e.g. fungi, plants, crinoids and insects, potentially suggest a product–precursor relationship. Here, we report perylene concentrations, 13C/12C, and D/H ratios from a Holocene sediment profile from the Qingpu trench, Yangtze Delta region, China. Perylene concentrations differ from those of pyrogenic PAHs, and rise to prominence in a stratigraphic interval that was dominated by woody vegetation as determined by palynology including fungal spores. In this zone, perylene concentrations exhibit an inverse relationship to the lignin marker guaiacol, D/H ratios between −284‰ and −317‰, similar to the methoxy groups in lignin, as well as co-variation with spores from wood-degrading fungi. 13C/12C of perylene differs from that of land plant wax alkanes and falls in the fractionation range expected for saprophytic fungi that utilise lignin, which is isotopically lighter than cellulose and whole wood. During progressive lignin degradation, the relative carbon isotopic ratio of the perylene decreases. We therefore hypothesise a relationship of perylene to the activity of wood-degrading fungi. To support our hypothesis, we analysed a wide range of Phanerozoic sediments and oils, and found perylene to generally be present in subordinate amounts before the evolutionary rise of vascular plants, and to be generally absent from marine-sourced oils, few exceptions being attributed perhaps to a contribution of marine and/or terrestrial-derived fungi, anoxia (especially under marine conditions) and/or contamination of core material by fungi. A series of low-molecular-weight aromatic quinones bearing the perylene-backbone were detected in Devonian and Cretaceous sediments, potentially representing precursor components to perylene. © 2009, Elsevier Ltd.
Oldest directly dated remains of sheep in China
(Springer Nature, 2014-11-24) Dodson, JR; Dodson, E; Banati, RB; Li, XQ; Atahan, P; Hu, SM; Middleton, RJ; Zhou, XY; Nan, S
The origins of domesticated sheep (Ovis sp.) in China remain unknown. Previous workers have speculated that sheep may have been present in China up to 7000 years ago, however many claims are based on associations with archaeological material rather than independent dates on sheep material. Here we present 7 radiocarbon dates on sheep bone from Inner Mongolia, Ningxia and Shaanxi provinces. DNA analysis on one of the bones confirms it is Ovis sp. The oldest ages are about 4700 to 4400 BCE and are thus the oldest objectively dated Ovis material in eastern Asia. The graphitisised bone collagen had δ13C values indicating some millet was represented in the diet. This probably indicates sheep were in a domestic setting where millet was grown. The younger samples had δ13C values indicating that even more millet was in the diet, and this was likely related to changes in foddering practices. © 2014, Macmillan Publishers Limited
Origin and spread of wheat in China
(Elsevier, 2013-07-15) Dodson, JR; Li, XQ; Zhou, XY; Zhao, KL; Sun, N; Atahan, P
Wheat was added as a new crop to the existing millet and rice based agricultural systems of China. Here we present 35 radiocarbon ages from wheat seeds collected from 18 sites between western (Xinjiang Province) and eastern (Henan Province) China. The earliest wheat ages cluster around 2100–1800 BCE in northern China's Hexi corridor of Gansu Province, where millet was already a well-established crop. Wheat first appears in Xinjiang and Henan about 300–400 years later, and perhaps a little earlier than this in Xinjiang, and we hypothesize that the likely route of wheat into China was via Russia through Gansu. © 2013, Elsevier Ltd.
Pollen, biomarker and stable isotope evidence of late quaternary environmental change at Lake McKenzie, southeast Queensland
(Springer, 2014-10-30) Atahan, P; Heijnis, H; Dodson, JR; Grice, K; Le Métayer, P; Taffs, K; Hembrow, SC; Woltering, M; Zawadzki, A
Unravelling links between climate change and vegetation response during the Quaternary is important if the climate–environment interactions of modern systems are to be fully understood. Using a sediment core from Lake McKenzie, Fraser Island, we reconstruct changes in the lake ecosystem and surrounding vegetation over the last ca. 36.9 cal kyr. Evidence is drawn from multiple sources, including pollen, micro-charcoal, biomarker and stable isotope (C and N) analyses, and is used to gain a better understanding of the nature and timing of past ecological changes that have occurred at the site. The glacial period of the record, from ca. 36.9 to 18.3 cal kyr BP, is characterised by an increased abundance of plants of the aquatic and littoral zone, indicating lower lake water levels. High abundance of biomarkers and microfossils of the colonial green alga Botryococcus occurred at this time and included large variation in individual botryococcene δ13C values. A slowing or ceasing of sediment accumulation occurred during the time period from ca. 18.3 to 14.0 cal kyr BP. By around 14.0 cal kyr BP fire activity in the area was reduced, as was abundance of littoral plants and terrestrial herbs, suggesting wetter conditions from that time. The Lake McKenzie pollen record conforms to existing records from Fraser Island by containing evidence of a period of reduced effective precipitation that commenced in the mid-Holocene. © Springer Science+Business Media Dordrecht 2014
Sediment-based record of lateglacial and holocene environmental changes from Guangfulin, Yangtze delta, eastern China
(SAGE Publications, 2007-12) Itzstein-Davey, F; Atahan, P; Dodson, JR; Taylor, D; Zheng, HB
Multiproxies of past environmental conditions, comprising 53 sediment samples analysed for their lithostratigraphic properties (mainly their charcoal, phytoliths and pollen contents) from an AMS C-14-dated sequence of sediments accumulating at Guangfulin, Yangtze delta, are presented. The oldest sediments recovered date to the Lateglacial when a mosaic of mixed (conifer-deciduous) temperate forest and wetland vegetation characterized the Study area. The Lateglacial-Holocene transition and much of the early Holocene record to c. 7400 yr BP appears to be missing from the sequence. The earliest evidence possibly representing human activities in the study area (the remains of cereals and indicators of forest) date to c. 7000 yr BP. A large increase in macrocharcoal remains c. 4700 yr BP is a more certain indication of human activities close to the study site, and may indicate the first occupation of what is now the location of a major archaeological excavation at Guangfulin. Technological changes during the Eastern Zhou Dynasty (770-221 Bc) may be responsible for an increased abundance of rice (Oryza sp.), and possibly also foxtail or Chinese millet (Setaria italica), detected in the Guangfulin record after c. 2400 yr BP. An abrupt sedimentary change at c. 4000 yr BP may represent a short-lived episode of catchment instability. Aside front this, the sediment record from Guangfulin contains no evidence of dramatic environmental changes that could have led to a major decline in agricultural productivity c. 4000 yr BP, as has been suggested for the lower Yangtze by some researchers, who associate this with the cultural transition from Liangzhu to Maqiao. The findings do, however, add weight to the argument that developments in rice-based agriculture on the Yangtze delta varied both spatially and temporally. © 2007, SAGE Publications
Temporal trends in millet consumption in northern China
(Elsevier, 2014-10-01) Atahan, P; Dodson, JR; Li, XQ; Zhou, XY; Chen, L; Barry, LA; Bertuch, F
Temporal trends in prehistoric millet consumption are investigated in two regions of northern China, in the Wei River valley and a northern zone that encompasses north-eastern Shaanxi, western Shanxi and south-central Inner Mongolia. By directly radiocarbon dating each sample investigated, inferences about the timing of dietary shifts inferred from stable carbon and nitrogen isotope compositions can be made with a high degree of precision. Evidence presented here indicates that humans living around 4000 years ago in both the Wei River valley and the northern zone were heavily dependent on millet for their subsistence. By ca. 2500 cal. yr BP, a major diversification of diet had occurred in the Wei River valley, with some consuming much larger proportions of C3 foods than previously. These C3 foods may have included the western-derived cereals – wheat, barley and oats – and also rice. © 2014, Elsevier Ltd.
Use of coal in the bronze age in China
(Sage, 2014-03-03) Dodson, JR; Li, XQ; Sun, N; Atahan, P; Zhou, XY; Liu, HB; Zhao, KL; Hu, SM; Yang, ZM
People in northern and western China were probably the first in the world to use coal as a source of energy in a consistent way. The ages cluster around 1900–2200 BC in modern day Inner Mongolia and Shanxi provinces. These are areas where near-surface coal is abundant today and woody vegetation was scant in the Bronze Age. Since coal is bulky to transport, it was probably not a cost-effective energy source in areas with abundant wood supply. The sites where coal was first used were probably occupied for a century to a few centuries at most and were associated with Bronze Age societies. The earliest age is about 3490 BC from a house site at Xiahe in Shaanxi Province; however, the coal is not securely tied to the radiocarbon ages and is assumed to have been used at this site sometime after 3490 BC. The elemental composition of modern mine and sedimentary coal in nearby archaeological contexts suggests that coal was used from local sources, and that elemental composition of coal may be a useful tool in identifying site origin of coal.

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