Radioisotopic Approaches to Understanding Lake Sediment History

Radioisotopic techniques provide powerful tools for reconstructing the history of lake sediments, offering critical insights into past environmental changes and human impacts. These techniques have contributed significantly to our understanding of past environmental change and have implications for current environmental management practices. This review comprehensively examines various radiometric dating techniques used for lake sediments, with a focus on natural, cosmogenic, and artificial radionuclides, including 210Pb, 137Cs, 241Am, 7Be, 3H, and 14C. The review highlights the widespread use of radionuclides in establishing sediment chronologies across different time scales, from short-term processes (days to decades) to long-term environmental reconstructions spanning thousands of years. Moreover, applications in limnological research are explored, including sedimentation rate estimation, reconstruction of pollution history of trace elements, nutrients, microplastics, and organic compounds, and assessment of anthropogenic impacts and catchment changes. The integration of radioisotopic methods with multiproxy paleolimnological approaches is emphasized as a powerful framework for reconstructing past environmental and ecological conditions. Despite their effectiveness, radioisotopic methods are exposed to several sources of uncertainty, including dispersion in atmospheric isotope flux, post-depositional processes, reservoir effects, and model assumptions. These challenges highlight the importance of careful methodological selection, site-specific evaluation, and rigorous uncertainty assessment in radioisotopic studies of lake sediments. Future research should emphasize refining sediment age-model calibration using region-specific sedimentation parameters and standardized validation procedures, and integrating radiometric techniques with geochemical, biological, and paleolimnological proxies to improve the reconstruction of environmental change in lacustrine systems. Such developments would enhance the interpretation of historical pollution records, sediment accumulation patterns, eutrophication history, and ecological variability, thereby providing scientifically robust information to support evidence-based lake management, restoration programs, and long-term conservation strategies.