Abstract:

The Horqin sandy land in Inner Mongolia is the largest sandy land in China with a mean annual precipitation of 380 mm. Historically the sandy land was a prairie and nowadays it is a mixed farming and grazing zone. Today, farmlands occupy a large portion of the entire region, which has major implications for ecological security, national food security, and farmers’ livelihoods. Soil water content is conspicuously different at the dune top and in the inter-dune depression. Based on the large interannual variation in precipitation and the topographical features of sand dunes, the research objective was to overlay the soil and land use maps interpreted by satellite imagery to delineate the dominant and hidden sandy lands. Using NDVI data of different precipitation years as the discrimination criteria, cultivated land with low NDVI can be transferred to grassland to avoid the risk of desertification in the drier years. Adapted to the regional geographic environment in semi-arid regions, this method of optimizing spatial allocation of land use could be consistent with ecological and production needs while being uncomplicated. The study could be used as a functional model for reducing desertification in semi-arid areas by using sand dunes as wind protection, abandoning large-scale land leveling engineering and developing rain-fed agriculture. In other words, land-use allocation and farmland consolidation should be in harmony with the regional geographical environment. Combining agricultural production and desertification prevention is a sustainable land use planning strategy.

Key words: Horqin sandy land, desertification combating, land use planning, farmland engineering design, method