Against the backdrop of fully implementing the "Great Food Outlook" national strategy, the comprehensive development and utilization of saline-alkali land and water resources is regarded as a key path to expand food production space and ensure food security. Xinjiang is one of the regions in China with the most abundant saline-alkaline water resources suitable for aquaculture, with a total area of more than 1.3 million hm² of fishable saline-alkaline waters, widely distributed in the Tarim River Basin, Junggar Basin, Turpan-Hami Basin and other regions, covering various types such as salt lakes, saline-alkali lakes, marsh wetlands and salinized reservoirs. Elucidating the hydrochemical characteristics and controlling mechanisms of different types of saline-alkaline water bodies in Xinjiang serves as the fundamental basis for assessing their aquaculture suitability and promoting the sustainable development of saline-alkali fisheries.

Objective To clarify the hydrochemical characteristics, controlling mechanisms, and aquaculture suitability of various types of saline-alkaline water bodies in Xinjiang, thereby providing support for the development and utilization of fisheries.

Methods Hydrochemical analyses were conducted on 513 water body samples collected across the entire Xinjiang region. The equivalent ratio relationships between Na⁺ and Cl⁻, as well as between Ca²⁺+Mg²⁺ and HCO₃⁻+SO₄²⁻, were investigated to reveal the hydrochemical heterogeneity and its formation mechanisms, and to propose aquaculture management strategies.

Results The spatial heterogeneity of hydrochemical characteristics among different water bodies is significant, governed by the combined effects of rock salt dissolution, evaporation and concentration, mineral weathering, cation exchange, and external input; groundwater is primarily controlled by the dissolution of carbonate rocks, with localized salinity enrichment; river and reservoir waters exhibit strong exchange capacity, stable ion ratios, and minimal osmotic stress; drainage canal water bodies are predominantly characterized by NaCl-type input, with Na⁺ enrichment in high-concentration zones, necessitating comprehensive assessment prior to utilization; lake water bodies show considerable variation in ion composition, with low-salinity lakes featuring coordinated ion ratios suitable for aquaculture; ponds and small ponds exhibit significant seasonal variations: evaporation and concentration during April–May lead to Na⁺ enrichment, which can easily cause ion imbalance, while multi-source mixing in September enhances ion dispersion. Across all water body types, the absolute concentrations of Ca²⁺ and Mg²⁺ are generally at a high level, providing a favorable hardness basis for aquaculture, but their ratio relative to Na⁺ is low in some water bodies, requiring attention to ion balance issues.

Conclusion The saline-alkaline water bodies in Xinjiang exhibit strong hydrochemical heterogeneity; therefore, a "tailored measures and phased management" system should be established: for groundwater, river water, and low-salinity lakes with stable ion ratios, these have high potential for large-scale cultivation of salt-tolerant economic species; for special water bodies such as high-salinity lakes and alkaline drainage channels, water quality should be optimized through ion regulation to accommodate specialized salt-tolerant organisms; for primary aquaculture water bodies such as ponds and shallow pools, the ion imbalance caused by evaporation and concentration should be prevented and controlled from April to May, while the ion ratios should be dynamically monitored and promptly adjusted in September. This study provides a scientific basis for the development of fisheries utilizing saline-alkaline water resources in Xinjiang.