Let 100 Billion Trees Bloom: China’s Great Green Wall
China’s Gobi and Taklamakan Deserts cover about one-tenth of the country’s land, but they’re responsible for a majority of the sand that inundates Beijing during gargantuan dust storms, making the city’s polluted air even more deadly.
Thanks to centuries of overgrazing, deforestation, and bad water management, the frequency and severity of those dust storms has been on the rise. But since the late 1970s, China has been working to stop the dust invasion by planting trees—billions of them—as part of a project called the Great Green Wall.
It’s one of the most aggressive environment-altering projects ever attempted, with a goal to plant 100 billion trees across 2,800 miles by 2050.
So is it affecting the dust storms? A new study says it is.
“Since its implementation, the program has improved vegetation, which decrease the intensity of dust storms,” study coauthor Minghong Tan a researcher at Beijing’s Institute of Geographic Sciences and Natural Resource Research, wrote in an email.
Researchers found that between 1981 and 1998, dust storm intensity would rise and fall in line with precipitation levels in areas away from the tree belt. The more it rained, the less intense the dust storms were for that year. But near the Great Green Wall, there was a decrease in dust storm intensity—regardless of the rainfall for the year.
The study’s results are contrary to recent reports that the Great Green Wall has had little to do with curbing China’s dust storms, saying that only climate effects—like the increasing rainfall levels over the past 30 years—has reduced dust storm frequency.
A recent article in The Economist asserted that even with the country’s northern forest cover rate rising from 5 percent in 1978 to 12 percent today, many of the trees are non-native pines and poplar and end up dying well before their normal lifespan.
Only around 15 percent of trees planted on China’s dry lands since 1949 survive today, Cao Shixiong of Beijing Forestry University, told The Economist.
In Ningxia, in Northwest China, a pest wiped out more than a billion planted poplar trees in 2000—erasing two decades of reforestation efforts in the region. That hasn’t tempered China’s resolve though. The nation announced that another 1.3 billion trees will be planted along the Silk Road in partnership with the United Nations Convention to Combat Desertification.
“There are positives and negatives associated with the Great Green Wall,” Tan wrote. “While vegetation is increasing and storm intensity is being reduced overall, some areas are seeing groundwater levels decreasing due to irrigation for planting trees. But the decrease is mainly the result of agricultural development and economic development.”