Temporal dynamics of environmental DNA (eDNA) as early-warning indicators of climate-driven ecosystem shifts in Diverse Saudi Habitats

Environmental DNA (eDNA) has become a powerful tool for non-invasive biodiversity monitoring, offering real-time insights into organismal presence and ecosystem dynamics.This study investigates how temporal oscillations in eDNA profiles can function as biomarkers for climate-induced changes in ecosystem structure and function.Focusing on freshwater lakes, forest soils, and coastal marine habitats across Saudi Arabia, we conducted multi-seasonal eDNA sampling and metabarcoding targeting 16S rRNA, COI, and ITS markers.These data were integrated with satellite-derived and on-site environmental parameters, including temperature, rainfall, and atmospheric CO 2 levels.Our findings reveal that eDNA signatures fluctuate in synchrony with seasonal and extreme climatic events.Notably, microbial richness in forest soils peaked during wet periods, while declines in coral-associated eDNA correlated with elevated sea surface temperatures.Indicator species analyses identified sentinel taxa responsive to heat, humidity, and rainfall variability.These patterns suggest that eDNA oscillations can serve as sensitive, real-time indicators of ecosystem stress, offering a dynamic framework for climate-resilient biodiversity monitoring.