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. Carbon losses amid water scarcity in climate-vulnerable drylands are a mounting challenge, and their restoration requires optimizing water-to-carbon biotransformation. Synthesizing thousands of worldwide experimental studies, we identify key biophysical pathways for enhancing carbon restoration and ecosystem resilience in global drylands, as follows: (i) Cropping diversification increases net primary productivity by 18.9% (n = 1296 studies); (ii) Regulated deficit irrigation cuts water use by 30–50% while improving yield-scaled water use efficiency by 3.4% (n = 9068 paired comparisons); (iii) Soil mulching increases land productivity by 22.2% (n = 48,144 paired comparisons); and (iv) Soil health rejuvenation strategies can sequester 1.2–3.8 t SOC ha⁻¹ yr⁻¹. Priorities to implement these biophysical pathways to enhance water-to-carbon biotransformation include: ‘smart’ irrigation, carbon dioxide fertilization-enhanced photosynthetic assimilation, rhizosphere engineering for microbiome-based nutrient solutions, biodegradable mulches replacing traditional polyethylene films, diversifying farming systems with low soil disturbance and climate-smart practices, and inclusive governance frameworks. These prioritized strategies reconcile water scarcity with carbon restoration to enhance dryland ecosystem resilience, which supports the UN’s Sustainable Development Goals. Crop diversification, regulated deficit irrigation, soil mulching, and soil health restoration can optimize water-to-carbon biotransformation in global drylands, according to a meta-analysis study.