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Showing 1 to 10 of 10 for “"Leaf waxes"”.
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Fossil C 4 plant signals in Southeast Atlantic Ocean continental margin sediments indicate climate-dependent vegetation changes on the adjacent continent
… in the predominance of C4 or C3 land plants. Leaf waxes of 35 C4 grasses and three C3 grasses were analysed. These investigations revealed that C4 grass waxes have significantly higher compound-specific delta13C values, high contents of n-C31 and n-C33 alkanes and the abundance of the n-C32 …
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Geochemical tools and paleoclimate clues : multi-molecular and isotropic investigations of tropical marine sediments and alpine ice
… records. Compounds derived from vascular plant leaf waxes and delivered to the marine sedimentary environment, including long-chain (C24-C32) n-alkanoic acids, were used as proxies for terrestrial vegetation type, aridity, and atmospheric circulation. Marine biomarkers, such as sterols and …
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Late Quaternary climate variability and terrestrial carbon cycling in tropical South America
… the past 20,000 years. Radiocarbon dating of leaf waxes in Cariaco Basin and Lake Titicaca sediment records indicates that waxes preserved in sediments are likely composed of a fresh component transported to sediments within decades of production by vegetation and an old component derived from …
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Aridification of the Indian subcontinent during the Holocene : implications for landscape evolution, sedimentation, carbon cycle, and human civilizations
… River). Carbon isotopes of terrestrial plant leaf waxes (δ13Cwax) preserved in sediment provide integrated and regionally extensive records of flora for both sites. For the Godavari River basin the δ13Cwax record shows a gradual increase in aridity-adapted vegetation from ~4,000 until 1,700 …
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Aridification of the Indian subcontinent during the Holocene : implications for landscape evolution, sedimentation, carbon cycle, and human civilizations
… River). Carbon isotopes of terrestrial plant leaf waxes ([delta]¹³Cwax) preserved in sediment provide integrated and regionally extensive records of flora for both sites. For the Godavari River basin the ([delta]¹³Cwax record shows a gradual increase in aridity-adapted vegetation from ~4,000 …
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Late Quaternary climate variability and terrestrial carbon cycling in tropical South America
… the past 20,000 years. Radiocarbon dating of leaf waxes in Cariaco Basin and Lake Titicaca sediment records indicates that waxes preserved in sediments are likely composed of a fresh component transported to sediments within decades of production by vegetation and an old component derived from …
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Environmental and biochemical controls on the molecular distribution and stable isotope composition of leaf wax biomarkers
Leaf wax n-alkyl lipids are increasingly used as proxies in palaeoclimate studies. Palaeovegetation assemblages are reconstructed from their molecular distribution patterns, while their δ13C and δ2H signals are thought to reflect plant-environment interactions and palaeohydrological shifts, …
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STRATIGRAPHIC FRAMEWORK AND QUATERNARY PALEOLIMNOLOGY OF THE LAKE TURKANA RIFT, KENYA
… was quantified using stable carbon isotopes of leaf waxes, and the amount effect was estimated using modern Kenyan amount effect coupled with a published basin fill model. It was determined that vegetation can account for up to -17 /, and amount effect estimations range from -17 / to - 24 / of …
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Glacial-Interglacial Variability of Eastern Pacific Hydroclimate
Unprecedented drought conditions in southwest North America (SWNA, defined as the region from southern California to southern Mexico, west of the continental divide) has raised alarms regarding water resource scarcity in a region with dense urban populations and vital agricultural industries. …
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Geochemical tools and paleoclimate clues : multi-molecular and isotopic investigations of tropical marine sediments and alpine ice
… records. Compounds derived from vascular plant leaf waxes and delivered to the marine sedimentary environment, including long-chain (C24-C32) nalkanoic acids, were used as proxies for terrestrial vegetation type, aridity, and atmospheric circulation. Marine biomarkers, such as sterols and …