Abstract
The continuous expansion of saline–alkali land has posed a severe threat to global food security, ecological stability, and sustainable agricultural development. Although conventional physical, chemical, and biological remediation technologies have achieved notable progress, they remain constrained by high costs, limited stability, and uncertain long-term effectiveness. As emerging soil-regulating materials, nanomaterials exhibit unique advantages—such as high specific surface area, active interfacial reactivity, and tailorable functionality—in improving soil structure, regulating salt-ion migration, enhancing water and nutrient retention, promoting directional nutrient release, and modulating microbial community activity. This review systematically summarizes the major mechanisms by which nanomaterials contribute to saline–alkali soil improvement, including structural optimization of soil physicochemical properties, precise regulation of ion fluxes and water behavior, and their emerging roles in synergistic water–fertilizer–pesticide management and intelligent soil environmental monitoring. It further evaluates the environmental behavior and potential ecological risks of nanomaterials, as well as the engineering, economic, and regulatory challenges associated with large-scale application. In light of current research gaps, future development should focus on constructing multifunctional and biodegradable nanocomposite systems, quantitatively elucidating nanomaterial–microbe interactions, and establishing integrated technological platforms for “intelligent sensing–precision regulation–sustainable remediation” tailored to saline–alkali land. Through critical synthesis and frontier analysis, this review clarifies the scientific basis and technological potential of nanomaterials for sustainable saline–alkali land management, providing theoretical guidance and strategic directions for developing safe, efficient, and sustainable agricultural soil remediation systems.
