Two thousand years after building the Great Wall of China, China is building the Green Wall of China to block dust storms from entering Northern China and Mongolia. Dust storms have ravaged Beijing every year and covered the city in a layer of sand and the sand storms are getting worse. So, what is the Green Wall?
Dust storms cover Beijing with layers of silt and sand. It's great for the car wash business.
More than 2,000 years ago, China began to build the Great Wall. Today, Mongolia is building its own seemingly implausible version: a zigzagging line of pines, willows, oleasters, junipers, hawthorns, aspens and other trees it hopes will someday stretch more than 2,000 miles across the desert. The so-called "Green Wall" is expected to take 30 years to complete and cost some $150 million or more.
This golfer is enjoying a sand storm in Beijing while practicing at the driving range. The Green Wall will undoubtedly improve the golf business.
The problem is becoming very severe in Mongolia. The amount of Mongolia's land that is suffering from desertification -- land that either has no vegetation at all or is slowly losing it -- could be as much as 50,000 square miles, an area the size of New York state, according to a leading Mongolian environmental group called Sain Uils, which means "good will" in Mongolian. Mongolia's Ministry of Nature and Environment says 683 rivers have dried up in recent years due to encroaching desert. China is also building a big wall.
The plan is known as the Green Great Wall - a 2,800-mile network of forest belts designed to stop the sands. Chinese scientists from the Ministry of Forestry believe the trees can serve as a windbreak and halt the advancing desert. In a recent report to the United Nations, Chinese officials predicted that the effort will "terminate expansion of new desertification caused by human factors" within a decade. By 2050, they claim, much of the arid land can be restored to a productive and sustainable state.
It will cost alot of money. Possibly the largest proposed ecological project in history, the new Great Wall calls for planting more than 9 million acres of forest at a cost of up to $8 billion. The project began last year as the fourth phase of an afforestation program launched in 1978. By 2010, the green belts are expected to stretch from outer Beijing through Inner Mongolia. To build the wall, the government has launched a two-pronged plan: Use aerial seeding to cover wide swaths of land where the soil is less arid, and pay farmers to plant trees and shrubs in areas that require closer attention. A $1.2 billion oversight system, consisting of mapping and land-surveillance databases, will be implemented. The government has also hammered out a dust-monitoring network with Japan and Korea.
The wall itself will be made up of an outer belt - ranging from 775 to 1,765 feet wide - with a sand fence along the perimeter. Inside, low-lying, sand-tolerant vegetation, arranged in optimized checkerboard patterns, will create an artificial ecosystem to stabilize the dunes. A 6-foot-wide gravel platform will hold sand down and encourage a soil crust to form. The government has also funded research to explore the use of genetically engineered plants, chemical dune stabilization, grass strains bred in space, and even farming techniques that will allow rice to grow in sandy soil.
Can an expansive row of trees and some strategically placed grass really stave off an encroaching desert? It worked before. In 1935, overgrazing and drought caused 850 million tons of topsoil to blow off the United States' southern Plains, leaving 4 million acres barren and creating the Dust Bowl. To address the problem, the newly formed Soil Conservation Service introduced the Shelterbelt Project - a 100-mile-wide strip of native trees bisecting the country from Canada to Texas. In a few years, it helped to reduce the amount of airborne soil by 60 percent.