In imperial China, government action to rangeland at the north-western frontier was for centuries determined by defense and what can be called “turning waste into use.” For the pacification of the region beyond the Great Wall, which frequently suffered from incursions by nomadic tribes,...

Soil is the largest carbon reservoir in terrestrial ecosystems, and minor changes in this reservoir can dramatically affect atmospheric CO 2 concentrations. The fragile ecological environment in the arid zone of northwest China is extremely susceptible to natural and anthropogenic factors,...