Impact of Phosphogypsum Application on Fungal Community Structure and Soil Health in Saline–Alkali-Affected Paddy Fields

Abstract

Modifying saline–alkali soil is crucial for ensuring food security and expanding arable land. Microorganisms play a key role in driving various biochemical processes in agricultural ecosystems. However, limited information exists on the changes in the microbial community and soil structure in soda saline-alkali soil under modified conditions. In this study, we examined the changes in soil physicochemical properties of saline–alkali soil altered by rice planting alone and by combined application of phosphogypsum in the Songnen Plain. The results demonstrated that phosphogypsum significantly improved the soil’s physicochemical properties; it notably reduced salinity and alkalinity while enhancing nutrient structure. Additionally, the utilization efficiency of carbon (C), nitrogen (N), and phosphorus (P) increased. Fungal community diversity also significantly improved, influenced mainly by soil water content (SWC), total organic carbon (TOC), soil organic matter (SOM), total nitrogen (TN) and sodium ion (Na+). TOC, SOM, TN, ESP, and Na+ served as the primary drivers affecting the fungal community. Our findings indicate that combining rice planting with phosphogypsum application effectively modifies saline–alkali soil, regulates fungal community structure, and enhances long-term soil health. Furthermore, the beneficial effects of phosphogypsum on saline–alkali soil persist for persists for several years, largely owing to its role in promoting microbial community growth.

The Green Development in Saline–Alkali Lands: The Evolutionary Game Framework of Small Farmers, Family Farms, and Seed Industry Enterprises

“…(2) Chemical amendment techniques involve the application of substances such as gypsum, sulfates, organic acids, and other chemical conditioners. The primary goal is to induce a substitution reaction between these chemical agents and the sodium ions in the soil, reducing exchangeable sodium, which in turn improves the soil's waterlogging and salinealkaline properties [13][14][15]. (3) Biological amendment techniques incorporate salt-tolerant microbial communities and organic fertilizers to increase the accumulation of organic matter in the soil, thereby enhancing soil structure.…”