Research Progress and Outlook on Desalination and Anti-Saline Re-precipitation Technologies for Coastal Saline-Alkali Soils

The remediation of saline-alkali land is of crucial importance in alleviating pressure on arable land resources and promoting sustainable agricultural development. The present paper undertakes a systematic review of the primary technical systems currently employed for the remediation of coastal saline-alkali land, and the underlying mechanisms that govern them. With regard to leaching desalination, the study focuses on analysing the desalination efficiency and limiting conditions of techniques such as freshwater irrigation, saline irrigation, and frozen saline irrigation. In the field of soil improvement, the mechanisms that regulate soil physicochemical properties are examined through the implementation of measures such as soil replacement, the addition of soil conditioners, and biological remediation. With regard to salt rebound suppression, the review considers the effectiveness of surface mulching and open ditch-closed pipe systems in controlling salt migration. A plethora of research has been conducted on the subject, and the results indicate that while each improvement technique possesses distinct advantages, they also exhibit limitations. Future efforts should focus on synergistic optimisation of multiple technologies to establish site-specific integrated management models for saline-alkali land, providing theoretical foundations and technical support for sustainable land resource utilisation in coastal regions.