In the 1950s, the Kubuqi Desert advanced northward by dozens of meters every year, almost cutting off the Yellow River. By the 1980s, frequent sandstorms had destroyed grasslands and farmlands, forcing many local residents to move south.
Experiments show that straw checkerboard sand barriers increase surface roughness on the desert surface, slow near-ground winds and help fix the sand in place, while the small "sand bowls" formed inside each grid help capture scarce moisture.
Kubuqi now has 14 such photovoltaic power stations. Under current desert-control plans, a "Photovoltaic Great Wall" about 400 kilometers long and 5 kilometers wide will snake along the northern edge of the desert by 2030 — a major milestone in humanity's fight against desertification.