Effects of Soil Amelioration on Wheat Growth, Nutrition, and Soil Microbiome Dynamics in Sandy Soil

Abstract Purpose Cropping regions in Western Australia (WA) face multiple soil constraints including acidity, nutrient deficiencies, compaction and water repellence, which limit crop productivity. Developing sustainable soil management strategies is therefore crucial. This study evaluates the effects of soil amendments—lime, gypsum, clay, compost, and synthetic fertilisers on soil health, nutrient availability, microbial function and wheat production. Methods A glasshouse experiment was conducted using undisturbed soil cores collected in a polyvinyl chloride (PVC) column from a field trial site where four treatments were applied: Control (no amendment), CLG (clay, lime, gypsum), CLG + NPK (CLG + nitrogen, phosphorus, and potassium fertilisers), and CLG + Compost. The experiment followed a completely randomised design with three replicates. Wheat growth, nutrient uptake, and soil chemical and microbial properties were assessed at three key wheat growth stages (Zadoks Z23, Z61, and Z92). Results All amendments significantly improved wheat growth, nutrient uptake, grain yield, and plant nutrient status, while enhancing soil chemical properties, microbial biomass carbon (MBC), and microbial diversity. CLG was the primary driver of soil improvement, and its combination with compost outperformed CLG with NPK fertilisers. Conclusion This study highlights the benefits of integrating organic and inorganic amendments to enhance the health and productivity of sandy soils by modulation of rhizospheric microbial composition. These findings support the development of sustainable soil management practices for wheat production. Future research should evaluate the long-term effects across diverse soils and cropping systems.