China’s fight against desertification

According to China’s Forestry and Grassland Administration, since the Sanbei Protection Forest Program (commonly known as the Great Green Wall) entered its key phase in 2023, the central government invested about 13.06 billion USD and implemented 544 important projects, completing the construction task on 16.27 million hectares. Currently, China’s desertified land area is decreasing by an average of 667,000 hectares per year.

Theo People’s DailyChina’s desertification areas are mainly concentrated in the northwest, north and northeast, collectively known as the “Three Bei” region with an area of ​​4,486 million km², accounting for nearly half of the country. The grass and forest cover here increased to 40.76% and the area of ​​treated desertified land was 67.82%. Along the Hexi Corridor, a 1,686 km stretch of oases and valleys in Gansu province, people have built 1,482 km of sand barriers. In Xinjiang, the protective forest belt in the Taklamakan Desert stretches for 3,046 km. Soil erosion in deserts and large sandy areas has decreased by about 40% since 2000.

According to Lei Jiaxiang, a researcher at the Xinjiang Institute of Ecology and Geography of the Academy of Sciences, to build the “Green Great Wall” on such a large area, China has built a system to monitor desertification from the ground, in the air and in space, and developed a series of techniques, biotechnology and chemistry to control sand. Authorities set up 18 science and technology testing locations throughout the Tam Bac area, deploying robots and planting machines equipped with Bac Dau navigation. They are also testing a “Smart Sand” AI model that aims to give planners a digital brain to help make sand control decisions.

In the Kubuqi Desert in Inner Mongolia, the local government applied a model that combines photovoltaic cells on top, fixed sand below, and planted grass in the middle. Farmers raise chickens under panels, grow tomatoes and potatoes in the shade, and turn barren sand dunes into cropland.

Theo Interesting Engineeringin April, the Xinjiang Institute of Ecology and Geography of the Chinese Academy of Sciences launched a number of initiatives focusing on sand control, preventing desertification, addressing wind erosion and soil desalination. Researchers test six new environmentally friendly materials to help stabilize sand at the edge of the desert. Among them is a solution based on basalt fibers made from melted volcanic rock, which helps reinforce soil and limit sand dunes from encroaching on agricultural land and surrounding infrastructure. In addition, the new project also uses fly ash, a fine dust industrial byproduct collected from coal combustion in thermal power plants. Researcher Pei Liang said the new materials could improve desertification control efficiency by 50% while reducing costs by about 30%.

Theo SCMPdeserts are difficult to reclaim because plants cannot survive on moving sand, but scientists at the Shapotou Desert Experimental Research Station of the Chinese Academy of Sciences (CAS) in Zhongwei City, Ningxia, found a solution to release large amounts of blue-green algae onto the arid terrain. Specially selected strains of blue-green algae can survive high temperatures and long periods of drought. When the rain comes, they come to life, spread rapidly and form a hard shell rich in hard biomass on the sand. This “living shell” stabilizes the sand dunes, capable of withstanding winds of up to 36 km/h, creating the perfect foundation for future plant growth.

The Ningxia government has applied this technique in its sand control strategy under the Tam Bac Protection Forest program and plans to increase the scale of use to 5,333-6,667 hectares in the next 5 years. According to Science and Technology Dailyit took researchers more than a decade to perfect the technique. First they selected 7 strains of blue-green algae from more than 300 species. The solutions containing blue-green algae are then mixed with organic matter and fine particles to form a paste-like mixture. This mixture is poured into a mold containing a hexagonal mesh, eventually creating particles that resemble clods of soil.