Impacts of Fallow Practices for Land Management Patterns on Soil Health in Rice‐Based Systems: A Microbial Perspective

ABSTRACT

Soil degradation and declining fertility threaten the sustainability of rice‐based agroecosystems, making it essential to understand how land management shapes soil health. This study elucidates the microbial mechanisms underlying land use–driven variations in soil health, characterizing microbial community structure and function across fallow and cultivation patterns, linking these to soil physicochemical properties and heavy metal dynamics, and identifying sensitive microbial indicators of soil ecological status. Results show that fallowed paddy fields significantly improve soil ecological quality by increasing moisture, organic matter, and nutrient availability, thereby promoting microbial diversity and basal metabolic activity. These fields consequently exhibit a markedly higher soil health index than upland and continuously cultivated soils. Although heavy metal contamination, particularly cadmium and nickel, remains a concern, fallow practices enhance contaminant stabilization and reduce bioavailability through improved soil conditions. Microbial analyses reveal clear land use–dependent differences, with paddy soils supporting greater diversity and more stable networks, whereas upland soils display stress‐adaptive functional traits. Basal metabolism and signal transduction emerge as key mediating functions linking land use to soil health, offering sensitive indicators when combined with network metrics. On the basis of these findings, we recommend optimizing fallow management in paddy systems, implementing integrated restoration strategies for uplands, and developing microbial‐informed soil monitoring frameworks. This study offers valuable insights for sustainable land management and soil ecosystem restoration.