Remote Sensing and eDNA Reveal Microbial Diversity Drivers in the Qaidam Basin (China)

Abstract The Qaidam Basin, situated on the northern Tibetan Plateau, is among Earth's most extreme deserts, characterized by a unique combination of high salinity, aridity, and solar radiation. These stressors make it an exceptional natural laboratory for studying microbial adaptation under Mars‐like conditions. In this study, we integrated MODIS remote sensing data with environmental DNA (eDNA) sequences from the NCBI database to investigate the spatial relationships between microbial diversity and environmental gradients. Key indices—including the Remote Sensing Ecological Index and Salinity Index—were derived to characterize vegetation, surface exposure, moisture, temperature, and salinity across the basin. Results identified the 5,000–6,000 m elevation zone as a major ecological transition, with significant changes in environmental indices and microbial community structure. Several bacterial phyla, such as Patescibacteria and Chloroflexi, exhibited strong and opposite correlations with salinity and surface temperature. Structural equation modeling showed that both the average level and spatial variability of salinity accounted for shifts in microbial diversity, whereas ecological heterogeneity exerted a negative influence. Strong model performance statistically supported these observed relationships. This interdisciplinary framework demonstrates the power of integrating satellite remote sensing with eDNA to guide microbial sampling strategies—offering scalable tools to investigate life in extreme environments and informing biosignature detection in Mars analog terrains.