Planting hardy grasses helps keep sand in place, but the wind can still whip away particles between the grasses. So Chunxiang Hu of the Chinese Academy of Sciences’s Institute of Hydrobiology in Wuhan has developed an alternative approach. She coats planted dunes with a mixture of photosynthesising cyanobacteria that can thrive in the semi-arid environment.
Grown in nearby ponds, the cyanobacteria are trucked into the desert every few days and sprayed over the dunes, where they form sticky filaments that hold soil particles in place and prevent them from being blown away. Cyanobacteria get their energy from sunlight via photosynthesis, and as part of the chemical reactions involved, they absorb carbon from the atmosphere and provide the organic matter the soil needs to be productive.