Application and Prospects of Microorganisms in the Amelioration of Saline-Alkali Soil

Saline-alkali land represents a highly promising arable land resource in our country. Its development and utilisation are of profound significance for maintaining the dynamic balance of national arable land resources, ensuring food production security, and promoting the sustainable development of the agricultural sector. In recent years, microbial amendment has garnered increasing attention due to its advantages of high efficiency, environmental friendliness, and strong sustainability. Studies have demonstrated that microorganisms improve soil ecology through diverse mechanisms, regulate soil quality, and significantly enhance crop yield and health, exhibiting a powerful ameliorative effect. Microorganisms consume salts in the soil through their metabolic activities, reduce the osmotic pressure of the soil solution, and minimise water loss. Bacillus, Enterobacter, and other bacteria enhance plant growth performance by secreting plant growth hormones and decomposing ethylene precursor substances, while also improving soil fertility through nitrogen fixation, phosphorus solubilisation, and other functions. They also dissolve minerals in the soil, increasing nutrient availability and promoting plant growth. Arbuscular mycorrhizal fungi and other beneficial microorganisms can form symbiotic relationships with plants, enhancing the plant's ability to absorb nutrients and improving its salt tolerance. Microbial communities can alter soil structure, reduce salt content, and form a co-evolutionary pattern between microorganisms and the soil. This article summarises research progress in microbial amendment of saline-alkali land, including the types and characteristics of microorganisms used, their mechanisms of action, and their effects in practical applications. Currently, China has established multiple microbial resource banks, providing a rich source of strains for the research and development of microbial fertilisers. However, the key mechanisms underlying microbial amendment of saline-alkali land have not yet been systematically summarised and thoroughly investigated, and the uncertainty and instability of its ameliorative effects limit the further promotion and application of microbial technology in saline-alkali land amendment. Future research directions should focus on the identification and functional validation of salt-alkali tolerance genes, the study of microbial community structure and function, and the mechanisms of interaction between microorganisms and plants. Through interdisciplinary collaboration involving bioinformatics, molecular biology, and other fields, further optimisation of microbial amendment technology is anticipated to provide more solid theoretical and technical support for the sustainable utilisation of saline-alkali land, thereby promoting sustainable agricultural development.