November 12, 2024 | Sustainability Science |
Introduction: This review, conducted by an international research team from Queensland University of Technology and the University of Queensland in Australia, together with Kyushu University in Japan, explores how joint carbon–biodiversity (JCB) credits could better reward co-benefits from land-based mitigation in Australia. Using evidence from agroforestry and assisted natural regeneration (ANR) on marginal agricultural lands, the authors assess whether combining carbon and biodiversity incentives can deliver larger climate and ecological gains than carbon-only schemes, and where such joint offsets are most promising geographically and economically.
Key findings: Australia’s extensive cleared marginal lands create strong opportunities for JCB deployment. Evidence from agroforestry and assisted natural regeneration shows that combining carbon and biodiversity incentives can deliver wider ecological and climate gains than carbon-only schemes, often with low establishment cost. The review notes that JCB is gaining relevance because carbon-focused incentives alone may overlook biodiversity decline, while joint credits can shift investment toward restoration outcomes that are frequently underprioritized. Studies indicate that even at relatively low carbon prices, large areas of marginal land could be profitably converted to JCB activities, with biodiversity monetization further expanding economic feasibility.
The study also recognizes significant governance challenges affecting both carbon and biodiversity offsets. International analyses suggest that many existing offsets may be ineffective, and Australia’s Emissions Reduction Fund has delivered limited emission reductions, underscoring the need for stronger oversight and more credible methodologies. The authors highlight risks such as biodiversity loss from monoculture plantations and emphasize the importance of accounting rules that prioritize native vegetation. Looking ahead, the review calls for internationally recognized methods to quantify and value biodiversity outcomes and for national regulatory frameworks that define where and how JCB schemes should operate. Clearer governance, consistent measurement approaches and alignment with international policy expectations are presented as essential for scaling JCB markets in a credible and equitable way.
