Intercropping Amomum villosum Enhances Soil Stratification, Nutrient Complementarity, and Microbial Communities in Rubber Plantations

Intercropping is widely promoted to sustain soil function, yet evidence for its application in rubber-based agroforestry, particularly with the shade-tolerant herb Amomum villosum, is limited. We evaluated whether A. villosum intercropping improves soil properties and reorganizes microbiomes across the vertical profile of mature rubber plantations. Soil samples were taken at 0-10, 10-20, and 20-30 cm depths in both intercropped and monoculture stands. Bacterial (16S rRNA V3-V4) and fungal (ITS2) communities were analyzed using high-throughput amplicon sequencing with depth-resolved data on diversity, composition, and functional inference (FAPROTAX, FUNGuild).