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There is increasing awareness of the need to correct for freshwater as well as marine reservoir effects when undertaking radiocarbon (14C) dating of human remains. Here, we explore the use of stable hydrogen isotopes (δ2H), alongside the more commonly used stable carbon (δ13C) and nitrogen isotopes (δ15N), for correcting 14C freshwater reservoir offsets in 10 paired human-faunal dates from graves at the prehistoric cemetery of Shamanka II, Lake Baikal, southern Siberia. Excluding one individual showing no offset, the average human-faunal offset was 515±175 14C yr. Linear regression models demonstrate a strong positive correlation between δ15N and δ2H ratios, supporting the use of δ2H as a proxy for trophic level. Both isotopes show moderate but significant correlations (r 2 ~ 0.45, p < 0.05) with 14C offsets (while δ13C on its own does not), though δ2H performs marginally better. A regression model using all three stable isotopes to predict 14C offsets accounts for approximately 65% of the variation in the latter (r 2=0.651, p =0.025), with both δ13C and δ2H, but not δ15N, contributing significantly. The results suggest that δ2H may be a useful proxy for freshwater reservoir corrections, though further work is needed. [ABSTRACT FROM AUTHOR]

Thirty-three paired accelerator mass spectrometry (AMS) radiocarbon dates on human and terrestrial faunal remains from the same Neolithic and Early Bronze Age graves are used to develop a correction for the freshwater reservoir effect (FRE) at Lake Baikal, Siberia. Excluding two outliers, stable nitrogen isotope (δ15N) values show a positive correlation (r2 = 0.672, p < 0.000) with offsets in 14C yr between paired human and fauna determinations. The highest offset observed in our data set is 622 yr, which is close to the value of ∼700 yr suggested for endemic seals in the lake. For each per mil increase in δ15N, the offset increases by 77 ± 10 yr in the overall data set. However, there are indications that different regression models apply in each of two microregions of Cis-Baikal. In the first, sites on the southwest shore of the lake and along the Angara River show a strong positive correlation between δ15N values and offsets in 14C yr (r2 = 0.814, p < 0.000). In the other, the Little Sea, both δ13C and δ15N values make significant contributions to the model (adjusted r2 = 0.878; δ13C p < 0.001; δ15N p < 0.000). This can be related to the complex 13C ecology of the lake, which displays one of the widest ranges of δ13C values known for any natural ecosystem. The results will be important in terms of refining the culture-history of the region, as well as exploring the dynamic interactions of hunter-gatherer communities both synchronically and diachronically. [ABSTRACT FROM AUTHOR]