Can China's Great Green Wall
Keep the Desert Away?
Photographer: Ian Teh
Text: Vince Beiser
In China today, a new Great Wall is being built not of stone, but of trees. Its aim: to hold back China’s vast and expanding deserts, which, due to climate change coupled with massive-scale logging, overgrazing, and water mismanagement, have been growing by hundreds of square miles every year. Roads, farmers’ fields, and even whole villages have disappeared under dunes. Every year, tens of thousands of tonnes of sand and dust are blown into Beijing and other cities, creating a vicious health hazard.
Beijing’s response is colossal even by Chinese standards. The project, officially dubbed the Green Great Wall, was launched in 1978 and is planned for completion in 2050. Aiming to plant some 88 million acres of protective forests in an area larger than California, it is easily the biggest tree-planting project in human history.
The results so far have been splendid — according to the government. Thousands of acres of moving dunes have been stabilised, and though deserts continue to spread in some areas, Beijing claims that on balance it has stopped and even begun to reverse the expansion.
Several scientists in China and abroad, however, say the actual results are unimpressive at best and disastrous at worst. Many of the trees, planted in areas where they don’t grow naturally, simply die after a year or two. Those that survive can soak up so much precious groundwater that native grasses and shrubs die of thirst, leaving the soil weaker than ever. Also, the monocultural artificial forests are vulnerable to disease; in 2000, a pest annihilated 1 billion poplars, the fruits of two decades of planting.
Yet the Green Great Wall has relevance far beyond China. According to the United Nations, desertification directly affects 250 million people worldwide, including parts of the United States. That’s why China’s response has spawned imitators: in Africa, eleven countries are fitfully trying to create a similar green barrier to hold back the spreading Sahara.