Radioecological dynamics in high-altitude ecosystems: Sources, processes, risk, and early-warning systems in mount...

This review presents an integrated conceptual framework describing radionuclide behavior in mountainous environments by synthesizing previously fragmented studies from Mount Aragats into a unified radioecological monitoring framework. Using Mount Aragats as a representative high-altitude ecosystem, the review integrates radionuclide sources, environmental processes, monitoring strategies, spatial modeling, and radiological assessment within a common perspective. Mountain regions function as dynamic orographic traps, where altitude-dependent atmospheric processes, complex topography, and heterogeneous geology govern radionuclide deposition, redistribution, and long-term retention across multiple environmental compartments, including atmospheric particulate matter, snow, soils, mosses, and river sediments. Methodological approaches adapted for complex terrain-including altitude-based sampling, baseline and background definition, geochemical indicators, regression modeling, Monte Carlo sensitivity analysis, and ecological risk assessment - are synthesized into a unified framework. These approaches improve the interpretation of spatial variability, identify the principal environmental drivers, distinguish natural background from anthropogenic inputs, and support more robust environmental assessment. The synthesis of long-term investigations from Mount Aragats demonstrates that reliable baseline establishment, combined with a process-based understanding of radionuclide behavior, is fundamental for environmental monitoring in mountainous regions. This review provides a transferable methodological approach for mountain radioecology supports environmental surveillance, baseline reassessment, anomaly detection, nuclear emergency preparedness, and early-warning systems in mountainous regions influenced by both natural and anthropogenic radiation sources.