Carbon market mechanisms and biodiversity co-benefits for sustainable development: a bibliometric analysis of global research trends and policy integration

Carbon markets are crucial climate mitigation mechanisms, yet their capacity to generate biodiversity co-benefits remains inadequately synthesized. With nations advancing Paris Agreement Article 6 commitments, implementing the Kunming-Montreal Global Biodiversity Framework (2022), and pursuing Sustainable Development Goals 13 (Climate Action) and 15 (Life on Land), examining how market-based instruments integrate biodiversity conservation has gained critical policy importance. This study analyzes global research patterns on carbon markets and biodiversity co-benefits through systematic bibliometric methods, revealing knowledge production trends, geographic disparities, thematic evolution, and policy integration trajectories spanning 2015 through October 2025. Web of Science Core Collection was systematically searched using structured queries combining carbon market terminology, biodiversity concepts, and sustainable development frameworks. Following PRISMA 2020 protocols, 2,331 initial records underwent sequential filtering for English language, peer-reviewed articles and reviews, relevant subject categories, and temporal scope (2015–2025), yielding 1,473 documents across 338 sources. Bibliometric analysis employed R software to examine publication trends, collaboration patterns, citation impacts, thematic structures, and keyword evolution. Research expanded significantly from 78 publications (2015) to 206 (2025), averaging 27.59 citations per document with 49.83% international collaboration. USA (1,135 author affiliations), China (783), and Australia (491) dominated research contributions, while UK exhibited highest citation impact (48.30 mean citations per document). Leading journals included Forests, Sustainability, and Forest Policy and Economics. Four thematic streams emerged: REDD + forest mechanisms (transitioning from REDD to REDD Plus, with REDD plateauing after 2021), blue carbon coastal systems (ascending 2021–2025, 141 documents), biodiversity conservation and governance (persistent themes, 254 and 179 documents respectively), and nature-based solutions (emerging 2022–2025, 41 documents). Keyword networks revealed strong linkages between ecosystem services, governance, and carbon sequestration, with temporal shifts from REDD implementation toward voluntary carbon markets and nature-based solutions. Findings demonstrate substantial transformation in carbon-biodiversity scholarship, evolving from basic REDD mechanisms toward enhanced REDD + frameworks and diversified approaches incorporating blue carbon, nature-based solutions, and emerging voluntary market mechanisms. However, REDD + remains the dominant forest carbon framework (224 documents), while voluntary carbon markets remain underexplored (8 documents) despite commercial growth. Persistent geographic disparities concentrate research production in developed nations (USA, China, Australia) despite implementation contexts in biodiversity-rich developing regions (Indonesia, Brazil, Kenya). Priority research directions should target long-term co-benefit verification protocols, carbon finance equity considerations, and empirical quantification of trade-offs between carbon and biodiversity objectives. Enhancing research capacity in biodiversity hotspots, establishing standardized co-benefit monitoring metrics, and ensuring Indigenous and local community participation are essential for advancing SDG 13 (Climate Action) and SDG 15 (Life on Land) while safeguarding ecosystem integrity and social equity.