China deploys drought-resilient algae to stabilize desert land

Chinese researchers are deploying large quantities of blue-green algae to stabilize shifting desert sands, marking one of the largest uses of microbes to reshape natural landscapes, according to reporting by the South China Morning Post.

The project centers on an “artificial crusting” technique developed at the Shapotou Desert Experimental Research Station, operated by the Chinese Academy of Sciences in the Ningxia region. Scientists are using selected strains of cyanobacteria—ancient, photosynthetic microorganisms—to bind loose sand into a stable soil-like surface known as a biocrust.

The cyanobacteria-based crust can withstand winds of up to 36 kilometers per hour and is expected to help reclaim about 6,667 hectares of desert land in Ningxia over the next five years. Researchers say the approach is low-cost and efficient, with potential applications for desert restoration and climate mitigation efforts beyond China.

Desert landscapes are challenging to rehabilitate because shifting sands prevent most plants from establishing a stable root system. In Ningxia, scientists addressed this challenge by identifying cyanobacteria capable of surviving extreme heat and prolonged drought. When exposed to even small amounts of rainfall, the microbes reactivate and secrete a biomass-rich matrix that binds sand particles together, creating what researchers describe as an “ecological skin.”

In natural conditions, the formation of a stable desert soil crust can take five to 10 years. The new technique reduces that process to about one year, providing a faster foundation for subsequent plant growth and ecosystem development.

The method evolved after early trials with liquid algae sprays proved impractical due to their reliance on heavy infrastructure. After screening more than 300 species, researchers selected seven cyanobacterial strains and combined them with organic matter into a nutrient-rich paste. This mixture is molded into hexagonal “solid seeds,” portable blocks designed to survive transport and remain dormant until rainfall triggers rapid growth.

Authorities in Ningxia plan to expand the use of the technology across more than 6,000 hectares of desert in the coming years. The effort forms part of China’s broader “Great Green Wall” initiative, which seeks to combat desertification not only through tree planting but also by stabilizing sand at its source.

China has already completed a 1,856-kilometer sand control belt in Inner Mongolia and is promoting its desert management technologies in other arid regions, including parts of Africa and Mongolia, as it pursues long-term strategies to halt land degradation.