Methodology for Integrating Isotopic and Nuclear Techniques to Assess Soil and Water Degradation in Terrestrial and Aquatic Ecosystems

Isotopic and nuclear techniques, including fallout radionuclides (FRNs), fingerprinting (FP), and isotope hydrology (IH), are essential tools for assessing soil and water degradation. However, as in state-of-the-art reviews, isolated application of FRNs, FP and IH limits their potential to address complex, interconnected environmental processes across landscapes. This study proposes a novel methodology based on the concept of Synergistic Convergence to integrate FRNs, FP, and IH into a unified framework for assessing soil and water degradation. Validated through a case study in Cuba’s Hanabanilla sub-basin, the five-stage methodology improves the identification of erosion hotspots, sediment sources, and water resource vulnerabilities. Results demonstrate that combining FRNs (quantifying soil redistribution), FP (tracing sediment sources), and IH (evaluating water dynamics) provides a robust approach for sustainable landscape management, according to the United Nations Sustainable Development Goals (SDGs) and the One Health framework. The integrated methodology proves superior to the non-integrated approach, connecting causes (erosion), drivers (water), and consequences (sedimentation, pollution). The Synergistic Convergence methodology effectively integrates isotopic and nuclear techniques (INTs) (FRNs, FP, and IH), enabling a holistic assessment of soil and water degradation and their interactions within terrestrial and aquatic ecosystems.