Optimizing rhizosphere metabolic circular economy toward sustainable ecosystems.

The rhizosphere metabolic circular economy (RMCE) governs the exchange, reuse, and reconfiguration of metabolites at the root-soil interface. Building on traditional binary plant-microbe models, this perspective advances an expanded RMCE framework by integrating three additional interdependent dimensions that explain how rhizosphere metabolic processes persist over time, organize across space, and recover under environmental stress. First, the live-dead plant-microbe continuum enables metabolic persistence by incorporating microbial necromass and root residues into long-term carbon sequestration and nutrient regeneration. Second, spatial organization across rhizosphere microzones optimizes microscale metabolic interactions through niche heterogeneity. Third, adaptive restoration dynamically re-establishes disrupted metabolic networks through coordinated plant-microbiome stress responses. We further outline scenario-based management strategies to translate the RMCE insights into practical solutions, which necessitates multiple approaches targeting root exudate quality, microbial necromass dynamics, rhizosphere spatial architecture, and cross-kingdom signaling. Together, these advances redefine RMCE as a dynamically regulated, spatially structured, and ecologically complex system, providing a more comprehensive basis for its optimization in sustainable ecosystems.