image: Analyzing nearly 800,000 bacterial operational taxonomic units (OTUs), the team found that 94.2% appear in at least two ecosystem types, while 46,305 OTUs are shared across all five. The pattern points to a single, interconnected multi-sphere bacterial metacommunity. Atmospheric aerosols appear to be a major source of glacier microbes, and glaciers themselves act as transfer hubs—microorganisms shared between the air and ice also turn up in significant numbers in downstream rivers, lakes, and soils.
Credit: ©Science China Press
Researchers from the Center for Pan-Third Pole Environment at Lanzhou University have revealed a climate-sensitive bacterial network that connects multiple ecosystems across the Tibetan Plateau. By analyzing 16S rRNA gene sequences from 3,373 samples spanning five ecosystem types and nine habitats, the team found that most bacteria are shared across environmental boundaries, forming a plateau-wide bacterial metacommunity.
Often called the "Asian Water Tower," the Tibetan Plateau is a natural laboratory for studying how different Earth spheres interact. As climate change drives glacier retreat, shifts in hydrology, and altered atmospheric deposition, the plateau's ecosystems are being reshaped. Microorganisms, the most abundant and widespread life forms on the planet, sit at the heart of these changes. Yet it has remained unclear whether microbial communities across these interconnected ecosystems form a single ecological network and how that network responds to climate change.
More than 94% of bacterial taxa were detected in at least two ecosystem types, while thousands occurred across all five, revealing extensive microbial connectivity throughout the plateau. The analyses also identified atmospheric aerosols as an important source of glacier microbes. Glaciers, in turn, act as ecological transfer hubs, linking the atmosphere with downstream rivers, lakes, and soils.
Precipitation emerged as the key climatic driver of community composition, but its effects depend on the habitat. In most ecosystems, more rainfall makes microbial communities more similar to one another. In glaciers, the opposite happens: increased precipitation actually makes each glacier's microbial profile more distinct.
"You can think of the whole plateau as one vast microbial network," explains the team's lead researcher. "The atmosphere drops the seeds, glaciers are the way stations, and rivers and lakes carry them onward. What surprised us most is precipitation's dual role. It connects the system, but on glaciers it works like a chisel—carving out a unique microbial signature for every glacier."
The study offers a new framework for understanding how plateau ecosystems respond to climate change at the microbial level. The authors argue that microbial monitoring should become part of comprehensive ecological security assessments for the Tibetan Plateau going forward.
About the Center for Pan-Third Pole Environment, Lanzhou University
The Center for Pan-Third Pole Environment at Lanzhou University investigates how climate change reshapes ecosystems in Earth's high mountains and polar regions. Its research integrates field observations, microbial ecology, biogeochemistry, multi-omics, and artificial intelligence to understand multi-sphere interactions in extreme environments. The Center has established an integrated research infrastructure that combines long-term environmental observations, biological specimen collections, and multi-sphere microbial resources and data. This infrastructure supports research spanning ecosystem processes, climate responses, and the discovery of microbial resources with potential applications in biotechnology and environmental sustainability. By advancing both fundamental understanding of life in extreme environments and the sustainable use of microbial resources, the Center aims to contribute scientific solutions to global challenges in climate change, ecosystem resilience, and human well-being.