Enhancing Carbon Restoration and Ecosystem Resilience in Global Drylands via Water-to-Carbon Biotransformation Strategies

The Earth's terrestrial carbon stocks have depleted an estimated 344 billion tons. In vulnerable drylands, restoring carbon sinks requires optimizing water-to-carbon biotransformation amid water scarcity. Using second-order meta-analysis, we identify key biophysical pathways for carbon restoration and ecosystem resilience: (i) Cropping diversification increases net primary productivity by 18.9% (<i>n</i> = 1,296 studies); (ii) Regulated deficit irrigation cuts water use by 30–50% while improving water use efficiency by 3.4% (<i>n</i> = 9,068); (iii) Soil mulching increases land productivity by 22.2% (<i>n</i> = 48,144); (iv) Soil health rejuvenation strategies sequester 1.2–3.8 t SOC ha⁻¹ yr⁻¹. Priorities to implement these biophysical pathways include water-smart irrigation, CO₂ fertilization-enhanced photosynthetic assimilation, rhizosphere engineering for microbiome-based nutrient solutions, bio-mulches replacing traditional plastic films, diversified farming systems with low soil disturbance, and inclusive governance frameworks. These strategies reconcile water scarcity with carbon restoration to enhance dryland ecosystem resilience and support the UN's Sustainable Development Goals.