학술논문

Lead and strontium isotopes as palaeodietary indicators in the Western Cape of South Africa.
Document Type
Article
Source
South African Journal of Science. May/Jun2020, Vol. 116 Issue 5/6, p89-96. 8p.
Subject
*STRONTIUM isotopes
*LEAD isotopes
*MARINE sediments
*COASTAL sediments
*ANIMAL ecology
*MASS spectrometry
*STRONTIUM ions
Language
ISSN
0038-2353
Abstract
We analysed the isotopic compositions of bioavailable strontium (Sr) and lead (Pb) in 47 samples of animals and plants derived from the various geological substrates of southwestern South Africa, to explore the utility of these isotope systems as dietary tracers. Measurements were made using high-resolution multi-collector inductively-coupled-plasma mass spectrometry (MC-ICP-MS). B7Sr/8&Sr could efficiently discriminate between geologically recent sediments of marine origin in near-coastal environments and older geologies further inland. However, 87Sr/B6Sr was not able to distinguish between the Cape Granite Suite and the Cape System (Table Mountain sandstones), whereas Pb isotopes could, demonstrating the utility of this hitherto underused isotope system. Bioavailable 87Sr/86Sr in near-coastal terrestrial environments is influenced by marine input whereas Pb isotopic ratios are not, because of low concentrations of Pb in seawater. There is considerable potential to use Pb isotopes as a dietary and palaeodietary tracer in near-coastal systems in fields as diverse as archaeology, palaeontology, wildlife ecology and forensics. [ABSTRACT FROM AUTHOR]