Three-North Shelter Forest Program

Map of China and the Gobi desert

China has seen 3,600 km² (1,400 sq mi) of grassland overtaken every year by the Gobi Desert.[6] Each year, dust storms blow off as much as 2,000 km² (800 sq mi) of topsoil, and the storms are increasing in severity each year. These storms also have serious agricultural effects for other nearby countries, such as Japan, North Korea, and South Korea.[7] The Green Wall project was begun in 1978, with the proposed end result of raising northern China's forest cover from 5 to 15 percent,[8] thereby reducing desertification.

The fourth and most recent phase of the project, started in 2003, has two parts: the use of aerial seeding to cover wide swathes of land where the soil is less arid, and the offering of cash incentives to farmers to plant trees and shrubs in areas that are more arid.[9] A $1.2 billion oversight system (including mapping and surveillance databases) is also to be implemented.[9] The "wall" will have a belt with sand-tolerant vegetation arranged in checkerboard patterns to stabilize the sand dunes. A gravel platform will be next to the vegetation to hold down sand and encourage a soil crust to form.[9] The trees should also serve as a windbreak from dust storms.

As of 2009, China's planted forest covered more than 500,000 square kilometers (increasing tree cover from 12% to 18%) – the largest artificial forest in the world.[10] Of the 53,000 hectares planted that year, a quarter died.[8] In 2008, winter storms destroyed 10% of the new forest stock, causing the World Bank to advise China to focus more on quality rather than quantity in its stock species.[10]

If the trees succeed in taking root, they could soak up large amounts of groundwater, which would be extremely problematic for arid regions like northern China.[9] For example, in Minqin, an area in north-western China, studies showed that groundwater levels have dropped by 12–19 metres since the advent of the project.[8]

Land erosion and overfarming have halted planting in many areas of the project. China's increasing levels of pollution has also weakened the soil, causing it to be unusable in many areas.[6]

Furthermore, planting blocks of fast-growing trees reduces the biodiversity of forested areas, creating areas that are not suitable to plants and animals normally found in forests. "China plants more trees than the rest of the world combined", says John McKinnon, the head of the EU-China Biodiversity Programme. "But the trouble is they tend to be monoculture plantations. They are not places where birds want to live." The lack of diversity also makes the trees more susceptible to disease, as in 2000, when one billion poplar trees were lost to disease, setting back 20 years of planting efforts.[8]

Liu Tuo, head of the desertification control office in the state forestry administration, is of the opinion that there are huge gaps in the country's efforts to reclaim the land that has become desert.[11] At present there are around 1.73 million sq kilometers that have become desert in China, of which 530,000 km² are treatable. But at the present rate of treating 1,717 km² per year, it would take 300 years to reclaim the land that has become desert.[12]

China's forest scientists argued that monoculture tree plantations are more effective at absorbing the greenhouse gas carbon dioxide than slow-growth forests,[10] so while diversity may be lower, the trees purportedly help to offset China's carbon emissions. However, a study released in 2016 finds that wild woodlands are much more effective than monocultural forests in storing carbon dioxide, with more resilient and greater tree health, size, lifespan, and depth of organic matter rich soil.[13]

(See List of countries by carbon dioxide emissions)

Gao Yuchuan, the Forest Bureau head of Jingbian County, Shanxi, stated that "planting for 10 years is not as good as enclosure for one year", referring to the alternative non-invasive restoration technique that fences off (encloses) a degraded area for two years to allow the land to restore itself.[8] Jiang Gaoming, an ecologist from the Chinese Academy of Sciences and proponent of enclosure, says that "planting trees in arid and semi-arid land violates [ecological] principles".[8] The worry is that the fragile land cannot support such massive, forced growth. Others worry that China is not doing enough on the social level. To succeed, many believe the government should encourage farmers financially to reduce livestock numbers or relocate away from arid areas.[9]

• Buffer strip
• Energy-efficient landscaping
• Great Green Wall
• Great Plains Shelterbelt, 1930s–40s, US
• Great Plan for the Transformation of Nature, 1940s–50s, Soviet Union
• Macro-engineering
• Sand fence
• Seawater greenhouse
• Deforestation and climate change

• China's Great Green Wall
• China's forest shelter project dubbed "green Great Wall"
• Grassland ecology to curb sandstorms
• Taming the Yellow Dragon - The Korea Herald