Quaternary International xxx (xxxx) xxx Please cite this article as: Zhanna V. Marchenko, Quaternary International, https://doi.org/10.1016/j.quaint.2021.06.006 Available online 12 June 2021 1040-6182/© 2021 Elsevier Ltd and INQUA. All rights reserved. δ 13 С and δ 15 N isotope analysis of modern freshwater fsh in the south of Western Siberia and its potential for palaeoreconstructions Zhanna V. Marchenko a, * , Svetlana V. Svyatko b , Artem E. Grishin a a Institute of Archaeology and Ethnography Russian Academy of Sciences, Siberian Branch, 17, Lavrentiev ave., Novosibirsk, 630090, Russia b 14CHRONO Centre for Climate, the Environment, and Chronology, School of Natural and Built Environment, Queen’s University Belfast, Northern Ireland, BT7 1NN, UK A R T I C L E INFO Keywords: Western Siberia Stable isotopes Archaeological and modern freshwater fsh Intermediate lake Palaeoenvironmental reconstruction Freshwater reservoir effects ABSTRACT Here, we present new δ 13 С and δ 15 N data for modern and archaeological freshwater fsh bone collagen from Siberia, together with summarized isotopic data for the Eurasian Steppe from previous research. Bio- archaeological material is an important source of information about people’s lifestyle, economy and diets, and palaeoenvironment. Stable isotope analysis of fsh bones, along with other palaeozoological and palaeobotanical material, is used for reconstruction of past human subsistence. The earlier isotopic study of human and faunal bones from the Preobrazhenka 6 site (south of Western Siberia) revealed elevated δ 13 C values in fsh bones (from 15.2 to 12.6‰), not typical for inland regions, from the settlement Neolithic layer of the site (Marchenko et al. 2015). In order to determine the possible sources of origin of the archaeological fsh with high δ 13 C in inland Central Eurasia, the isotopic composition of modern fsh from rivers and lakes of the south of Western Siberia was analysed. The results show a large range of δ 13 C in modern fsh bones – from 29.6 to 8.3‰. Fish with high carbon isotopic values came from small, rather ancient (within the Holocene period) endorheic lakes. 1. Introduction Carbon (δ 13 C) and nitrogen (δ 15 N) stable isotope ratios for fsh bones from archaeological contexts are typically used as a background data, i. e. as potential food sources, associated with the reconstruction of pre- historic human diets. As a number of studies have shown, this method is most effective when there is a clear isotopic differentiation between the terrestrial and marine components of the diet: in marine ecosystems, δ 13 C and δ 15 N are usually elevated, which primarily allows dis- tinguishing the diet of coastal inhabitants from hunters of terrestrial mammals (Chisholm et al., 1982; Schoeninger et al., 1983). Freshwater fsh can also be characterised by high nitrogen values, but, unlike ma- rine fauna, are usually lower in δ 13 C (Fry and Sherr, 1984). Therefore, lower δ 13 C with elevated δ 15 N values in collagen of humans from con- tinental areas are often associated with the consumption of freshwater fsh (e.g. Dufour et al., 1999), including among pastoral and nomadic communities (O’Connell et al., 2003; Privat et al., 2005; Murphy et al., 2013; Svyatko et al., 2013; Ventresca Miller et al., 2014). However, quite often such reconstructions of human palaeodiets are based only on isotopic results from human bone collagen and faunal isotopic data (including fsh) from other regions as comparative material, which can complicate determination of the main sources of dietary protein in a local context. The isotopic differentiation of terrestrial and freshwater food sources has its own challenges. Previous studies have demonstrated that isotopic values of freshwater fsh can vary signifcantly (36 to 17‰ in δ 13 C; 6–16‰ in δ 15 N) and completely overlap those of terrestrial herbivores, whose diets are based on C 3 plants (30.5 to 20‰ in δ 13 C; 4.5–7.5‰ in δ 15 N), and predatory mammals (29 to 19‰ in δ 13 C; 8–15‰ in δ 15 N; Dufour et al., 1999). Furthermore, isotopic variations can appear in fsh from the same basin as a result of different habitats and ecology. For example, fsh from marshy foodplains are lower in δ 13 C values than fsh inhabiting the main streamway of a river (Fry, 2002). Meanwhile, pelagic fsh are lower in δ 13 C than coastal fsh (France, 1995; Hecky and Hesslein, 1995). In any waterbody, δ 15 N values in fsh can vary depending on type and dietary pattern (carnivorous, non-carnivorous, omnivorous), size and age (Spies et al., 1989; Gu et al., 1996). As such, for example, within a single waterbody, higher δ 15 N can be characteristic of fsh consuming dead organic matter from the bottom, as compared to pelagic species (Estep and Vigg, 1985), although this is not the case for the Lake Baikal ecosystem discussed below and depends on specifc dietary patterns of the compared fsh (i.e. non-carnivore vs * Corresponding author. E-mail address: afrika_77@mail.ru (Z.V. Marchenko). Contents lists available at ScienceDirect Quaternary International journal homepage: www.elsevier.com/locate/quaint https://doi.org/10.1016/j.quaint.2021.06.006 Received 4 November 2020; Received in revised form 7 June 2021; Accepted 7 June 2021