Integration of digestate in energy crop production: a review of opportunities for sustainable agroenergy systems

The integration of digestate in energy crop production represents a promising approach for sustainable agroenergy systems, but evidence quality and practical implementation guidelines remain inadequately developed. This PRISMA 2020-compliant systematic review synthesized 42 studies (38% high-quality, 83% temperate bias) to assess evidence reliability, quantify climate-dependent performance variations, and develop implementation frameworks distinguishing universal principles from region-specific adaptations. Meta-analysis demonstrated consistent positive yield responses (18.3%, 95% CI: 12.1-24.7%) with statistically significant climate moderation (temperate: 23.2% vs. subtropical: 11.4%, p