Abstract:
The Xinjiang Production and Construction Corps (XPCC) is situated in a prototypical arid region of China. State-of-the-art technologies have realized to prevent the land degradation in saline-alkali land. Land governance pathways can provide for soil restoration in the country, significantly contributing to sustainable agriculture and national food security. A systematic review was presented to divide into the three long-term stages in the XPCC, thus tracing from the basic engineering to advanced system integration. The initial stage (1950s-1970s) was characterized by extensive engineering interventions. The strategy was fully met the needs of land reclamation. The salts were physically extracted from the root zone via open ditch drainage networks to reduce the groundwater table, supplemented by flood irrigation to leach soluble salts. These foundational measures were crucial to control the initial salinity. It was often required for more efficient approaches. The following period (1980s-1990s) was characterized by the strategic shift into the physical and chemical techniques. According to the drainage infrastructure, the simple irrigation and leaching were evolved to combine the measures suitable for the regional conditions: physical practices, such as the deep plowing, sand-soil blending, and surface salt removal; Biological measures like the organic manure and planting green manure; and chemical/engineering, such as flue gas desulfurization gypsum and subsurface pipe drainage. Emerging irrigation technologies, such as film-hole furrow irrigation, were used to transit from only symptoms to soil health. A revolutionary advancement occurred in 1996 with the widespread adoption of drip irrigation under plastic mulch. Water, fertilizer, and salt were precisely regulated in the crop root zone. Water and nutrients were directly delivered to plant roots using emitters covered by plastic film. Evaporation was reduced to inhibit upward salt movement in the saline-alkali land. Evaporation and soil salinization were suppressed to regulate the soil temperature after mulching. Conventional leaching was shifted to active, precise salt control. Six governance models were developed under specific conditions in XPCC: the irrigation-drainage synergistic model for heavily saline land in rice cultivation; the precise salt control for moderately saline land with drip irrigation; the water-saving salt suppression for lightly saline land in dry seeding; the biological fertility enhancement for compacted soils; the ecological reconstruction using brackish water and aquaculture; and the long-term precision management of water, fertilizer and salt. Collectively, the technological system also centered on the water-salt-fertilizer nexus. Challenges remained in the XPCC. Specifically, the fragile oasis agro-ecosystem was characterized by extreme aridity, high evapotranspiration, and limited water resources, indicating the water management as the critical factor. Water resource was further intensified under pressure. Additionally, the limited genetic diversity of existing salt-tolerant crop varieties was restricted the potential for profitable cultivation on moderate to severely saline soils. The technological infrastructure also hindered adaptive strategies for the real-time, intelligent monitoring and precise soil salinity. In absence of a holistic framework to enhance the overall productivity, current approaches focused on individual components rather than integrating land improvement, crop production, and ecosystem stability. Future strategies can shift towards more integrated, intelligent, and ecologically balanced approaches, thereby promoting a "Water-Land-Sand-Crop-Energy" governance model. A globally leading model can be established to transform saline-alkali lands from marginal resources into productive assets, thereby contributing to global food security and agricultural resilience against climate change.