Δ¹⁴C and δ¹³C Variations in Organic Fractions of Baltic Sea Sediments

Abstract

ABSTRACT. This article investigates variations of Δ 14 C and δ 13C of total organic carbon (TOC) in sediments as well as in humic acids, lipid, and phospholipid fractions isolated from the surface (0-3 cm) sediment samples collected in the Curonian Lagoon and in the Baltic Sea. This study was performed to estimate relative contributions of the marine and terrestrial inputs to organic carbon in sediments, to assess a possible effect of petroleum hydrocarbon contamination on radiocarbon signatures, and to elucidate a possible leakage of chemical warfare agents (CWA) at the Gotland Deep dumpsite. Depleted Δ 14 C values of the TOC (down to -453‰) and of the total lipid extracts (down to -812.4‰) were detected at the CWA dumpsite. Application of the compound-specific method indicated a possible effect of CWA on depleted Δ 14 C and δ 13 C values in the investigated organic carbon fractions. The obtained results have indicated the different origin and behavior of lipids and TOC at the CWA dumpsite as compared to the area affected by the terrestrial-freshwater OC input. The Δ 14 C data of the TOC and total lipid extracts showed that recent sediments at the CWA dumpsite contain an excess of fossil carbon capable of influencing the 14 C dating at the site.

Carbon Isotopes as Tracers of Organic and Inorganic Carbon in Baltic Sea Sediments

“…The radiocarbon analysis of sediment samples collected during 2012–2016 in the Lithuanian economic zone (Figure 1) showed wide range of Δ 14 C TOC values (from –446.1‰ to –6.7‰) (Lujaniene et al 2015). The total lipid extracts (TLE) Δ 14 C TLE values (the average value of –536.0‰) on average were more depleted as compared to the Δ 14 C TOC (with two exceptions that showed enriched values).…”

“…Climate change and anthropogenic impacts have affected sources and redistribution of organic matter in the marine environment. Radiocarbon ( 14 C) has been successfully employed to trace the origin and circulation of environmental organic matters (Druffel and Bauer 2000; Wakeham et al 2006; Lujaniene et al 2015). Among other factors, organic substances of various origin introduced into the marine environment and deposited on the seabed may be subject to utilization and decomposition by microorganisms.…”

New ultra-sensitive radioanalytical technologies for new science

“…In the framework of marine radioactivity assessment of radioactive waste dumping sites (Atlantic, Arctic and Pacific Oceans), radiological assessment of nuclear bomb tests sites (French and USA testing sites in the Pacific Ocean), as well as a wide range of marine radioactivity surveys we established background levels of key radionuclides ( 3 H, 14 C, 90 Sr, 129 I, 137 Cs, U, Pu and Am isotopes) in the World Ocean so any recent releases of these radionuclides would be easily recognized over the global fallout background [ 1 – 4 , 93 , 99 , 176 – 179 ].…”

Spectroscopic detection of radiocarbon dioxide based on optical feedback linear cavity enhanced absorption spectroscopy

“…1 The natural abundance of 14 C, that is, 14 C/C, in the environment is exceedingly scarce, with a numerical value of 1.2 × 10 −12 , commonly referred to as 1 modern carbon (MC). However, the detection of 14 C concentration is of great significance and can be used for dating, 2 marine environmental research, 3 biomedical research, emission trace of greenhouse gas, and other fields.…”