ABSTRACT
The isotopic composition of various biological substances is one of the most popular objects of studies by paleoclimatologists and ecologists who study the relatively recent climatic changes in the Holocene, as well as in previous geological epochs [1-5]. The wide popularity of this type of research is based on a relationship between the isotopic composition of carbon, hydrogen, and oxygen in the environment (e.g. ocean, sea, and lake waters, rain and snow precipitation, carbon dioxide in the atmosphere) and the isotopic composition of these elements in organic and inorganic components of the flora and fauna (e.g. cellulose and lipids of plants, animal bones, phosphates, carbonates, shells) found in continental and marine environments. Since the organically bound hydrogen, carbon and oxygen participate in the global hydrological and carbon cycles, climate changes affecting these cycles have a significant impact on their isotopic composition. Thus, having a clear understanding of the degree of fractionation of isotopes of a particular element in the biosynthesis processes as well as the level of diagenetic history of the sample, the researcher has the opportunity to study the climate-induced changes in these cycles in the past.
