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Great Wall of China protected from erosion by coat of lichen and moss
A section of the Great Wall of China made with rammed earth AtthameeNi/Shutterstock The Great Wall of China is being protected from erosion by a “biocrust” of moss, lichen and cyanobacteria, much as the wall once shielded the country from northern invasions. The wall, built and rebuilt many times between about 200 BC and the…