[Research progresses on the effects of rice cultivation on amelioration of saline-alkali soil]

Saline-alkali soils pose severe challenges to agricultural production and the sustainable utilization of land resources. Efficient amelioration and utilization of saline-alkali land is of great significance for expanding agricultural production and safeguarding national food security. Rice cultivation is an important approach to ameliorate saline-alkali soils, offering dual benefits in ecological improvement and economic development. We reviewed research on improving saline-alkali land through rice cultivation over the past two decades. Long-term (≥5 years) rice cultivation exerts positive effects on saline-alkali soils. Specifically, soil pH and electrical conductivity decreased by 5.9%-23.0% and 22.1%-89.7%, respectively. Soil organic matter, alkali-hydrolyzable nitrogen, available phosphorus, and available potassium contents increased significantly by 60.0%-66.7%, 90.2%-131.0%, 68.9%-89.2%, and 6.7%-179.2%, respectively. In addition, the richness (Ace index) of soil bacterial and fungal communities increased by 10.5%-23.4% and 23.8%-52.8%, and the Shannon index increased by 60.9%-98.7% and 18.3%-107.0%, respectively. Improvements in the physicochemical and biological properties of saline-alkali soils enhanced rice yield and yield components, with thousand-grain weight, grains per panicle, and overall grain yield be increased by 10.1%-17.2%, 9.3%-46.6%, and 48.2%-91.1%, respectively. Future research should focus on innovations in salt-alkali tolerant rice germplasm resources and variety breeding, rhizosphere microbial remediation strategies for salt-alkali tolerant rice, carbon sequestration potential assessment systems for saline-alkali paddy fields, and diversified development approaches. These efforts would provide a reference for deeply exploring the comprehensive utilization potential of saline-alkali land and advancing the sustainable use and efficient remediation.