气候变化领域集成服务门户(CCPortal): Identifying the ‘savanna’ signature in lacustrine sediments in northern Australia

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DOI	10.1016/j.quascirev.2018.11.002
	Identifying the ‘savanna’ signature in lacustrine sediments in northern Australia
	Bird M.I.; Brand M.; Diefendorf A.F.; Haig J.L.; Hutley L.B.; Levchenko V.; Ridd P.V.; Rowe C.; Whinney J.; Wurster C.M.; Zwart C.
发表日期	2019
ISSN	0277-3791
起始页码	233
结束页码	247
卷号	203
英文摘要	This study reports palynological and geochemical results for modern and ancient sediments from 19 lakes on a rainfall gradient (784–1880 mm), across a range of savannas in Northern Australia. All proxies varied significantly across the range of sites examined, providing a robust envelope of values that can reliably be employed to identify a savanna signature in the sedimentary record. While the results indicate it is possible to identify a savanna, we found only three statistically significant relationships between any proxy measured in surface sediments and the major climate driver of savanna vegetation composition (rainfall amount). This is because edaphic factors play a dominant role in determining vegetation composition and also potentially because of the impact of land use change. Measures of fire determined by charcoal counting were positively correlated with geochemical measures of pyrogenic carbon abundance, suggesting both record a similar signal. While measures of fire incidence were not correlated with rainfall, there was a significant positive correlation between charcoal abundance and number of fires early in the dry season, suggesting that charcoal abundance is controlled more by the number/timing of fires than climate. There was also a significant correlation between the δ13C-value of pyrogenic carbon and tree:grass ratio derived from palynological indicators, indicating that the δ13C-value of PyC is a reliable indicator of savanna ‘woodiness’. Comparison of the carbon isotope composition of total organic carbon, PyC and n-alkanes between modern and Holocene sediments suggest that the savannas of the region have remained either similar in ‘woodiness’ or have thickened over the last millennia. © 2018 Elsevier Ltd
英文关键词	Continental biomarkers; Palaeoecology; Paleoclimatology; Palynology; Quaternary; Radiocarbon; Southern Pacific; Stable isotope; Vegetation dynamics
语种	英语
scopus关键词	Charcoal; Fires; Geochemistry; Isotopes; Land use; Organic carbon; Paraffins; Rain; Vegetation; Palaeoecology; Paleoclimatology; Palynology; Quaternary; Radiocarbon; Southern Pacific; Stable isotopes; Vegetation dynamics; Sediments; biomarker; carbon isotope; charcoal; Holocene; land use change; paleoclimate; paleoecology; palynology; Quaternary; radiocarbon dating; rainfall; savanna; total organic carbon; vegetation cover; vegetation dynamics; Australia; Pacific Ocean; Pacific Ocean (South)
来源期刊	Quaternary Science Reviews
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/152069
作者单位	College of Science and Engineering, James Cook University, P.O. Box 6811, Cairns, Queensland 4870, Australia; Centre for Tropical Environmental and Sustainability Science, James Cook University, P.O. Box 6811, Cairns, Queensland 4870, Australia; ARC Centre of Excellence for Australian Biodiversity and Heritage, James Cook University, P.O. Box 6811, Cairns, Queensland 4870, Australia; Department of Geology, University of Cincinnati, P.O. Box 210013, Cincinnati, OH 45221-0013, United States; School of Environment and Research Institute for the Environment and Livelihoods, Charles Darwin University, Northern Territory, Darwin, 0909, Australia; Australian Nuclear Science and Technology Organization, Locked Bag 2001, Kirrawee DCNSW 2232, Australia; School of Engineering and Physical Sciences, James Cook University, Townsville, Queensland 4811, Australia
推荐引用方式 GB/T 7714	Bird M.I.,Brand M.,Diefendorf A.F.,等. Identifying the ‘savanna’ signature in lacustrine sediments in northern Australia[J],2019,203.
APA	Bird M.I..,Brand M..,Diefendorf A.F..,Haig J.L..,Hutley L.B..,...&Zwart C..(2019).Identifying the ‘savanna’ signature in lacustrine sediments in northern Australia.Quaternary Science Reviews,203.
MLA	Bird M.I.,et al."Identifying the ‘savanna’ signature in lacustrine sediments in northern Australia".Quaternary Science Reviews 203(2019).