It is well known that the reason resulting in devastation of natural vegetation is soil erosion. It is useless in adopting“closing up the hills and planting trees”and “closing up the deserts and planting grass” without solving the soil quality and soil layer problems, which has been proved by our experience for many years. Let’s suppose that if we can cover 20-50 cm of artificial soil on the areas where annual precipitation is more than 500 mm but have not any soil nor woods or grass, virgin forests will be grown in these places in 200 years. The key to solve grassland desertification also lies in increasing clay mineral and organic matter in soil. I have already put forward the opinion of making use of the loess from the Loess Plateau and organic wastes from Beijing and Tianjin and Tangshan to improve the grassland in Inner Mongolia on a large scale. Besides, the artificial soil technology and engineering agricultural technique should be carried out to solve the problems of retaining water, irrigating the fields and controlling soil salinization and so on. Because it is such a huge project, who can decide to carry it out?
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