Principle, technologies, and benefits of zoned desertification control mode of desert-crossing highway grids.

Abstract

The pioneering zoned desertification control mode of desert-crossing highway grids in Ongniud Banner has received widespread societal acclaim. However, the principle, technology, and benefits of this mode have not been systematically summarized, which affects its cognition and promotion in the field of desertification control. We synthesized multi-source data from field investigations, interview and literature to elucidate design principle of the zoned desertification control mode of desert-crossing highway grids, configuration characteristics of "three belts" (dune-fixing and forestation belt, enclosure conservation belt, and aerial seeding belt), vegetation and soil restoration processes, and influences on production and living. The results showed that the desert-crossing highway grids and the "three belts" protective system cut and separated large areas of active sand dunes, blocking sand source, controlling wind-sand hazards, promoting transportation, and facilitating people's livelihoods. After seven years of vegetation restoration, the number of plant species has increased to more than 16. The vegetation gradually changed from psammophytes to xerophytes. Both species diversity of vegetation and soil seed banks increased significantly. From the dune-fixing and forestation belt, enclosure conservation belt, and aerial seeding belt to uncontrolled active sand dunes in the center of a grid, soil water presented deficit, balance and surplus state, respectively, maintaining water balance in the grid as a whole. The mode in line with principles of aeolian sand dynamics and restoration ecology formed the pattern of "highways cutting sand dunes, grids locking and fixing sand dunes, progressive restoration by the 'three belts', left blank to store water in the center". This mode demonstrates the coordinated deve-lopment between controlling wind-sand hazards and restoring vegetation, constructing artificial vegetation and maintaining water balance, as well as coordinating ecology, production, and livelihoods. This mode embodies a top-level design philosophy guided by county-level planning units, multi-department collaboration, and integration of multiple technologies. It is remarkable in ecological and social benefits in formatting "Ongniud Banner mode" with characteristics of regional desertification control. The mode has the extensive replicability value for sandy land rehabilitation across northern China.