Officials have long hoped that trees could help solve the problem, by acting as windbreaks and anchoring the ground in place with their roots. For decades they have been planting a ring of vegetation round the [Taklamakan] desert’s edge that is 3,000km long and over 1km wide in places. This year hundreds of thousands of workers were mobilised to finish the last stretch. On November 28th the final section of trees was planted in Yutian county, on the southern side of the Taklamakan. The desert is now “locked shut”, say officials.
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China boasts that the scheme has already been a great success and highlights its technological prowess. According to official data, tree cover in arid areas of northern China has increased from 5% to 14% since the project began. These new trees have protected 23m hectares of agricultural land from desert sands, say officials. And the green wall may have even turned the sands back a fraction. A decade ago 27.2% of China’s total land area was desert. Now that proportion has fallen to 26.8%.
But not all this progress is thanks to the green wall. A big reason China’s deserts are no longer expanding is that northern China is seeing more rain, say researchers at the Northwest Institute of Eco-Environment and Resources, a state-backed think-tank. Human efforts, such as planting trees, have accounted for only about half the reduction in the size of deserts over the past two decades, the researchers estimated. (Others studies have found that afforestation had even less of an effect.)
Critics also question how sustainable the green wall is. For decades local officials rushed to plant trees in order to hit targets set by the government. Many were unsuited to the arid climates of northern China, so they failed to sprout or quickly died. Others were packed in too densely, draining the region’s groundwater reserves and making desertification more likely.
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Chinese officials seem to be learning from their mistakes. Over the past few years they have been creating the wall in a more sophisticated way, planting different types of trees, shrubs and grasses, depending on local ecosystems. They have also let farmers plant more profitable trees, such as those bearing dates and walnuts.
Lately China’s leader, Xi Jinping, has been more sombre when discussing the challenges facing the green-wall project. After a spike in the number of sandstorms affecting Beijing last year, which spurred debate over the effectiveness of afforestation, Mr Xi met officials in Inner Mongolia, a region of northern China prone to desertification. Beating back the desert would be “arduous and uncertain”, he told them, akin to “rolling a stone up a hill”.
https://archive.is/FVimm
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