Terrestrial carbon stocks and biodiversity: key knowledge gaps and some policy implications

The need to understand relationships between biodiversity and carbon cycling (including carbon sequestration) has risen in prominence owing to international interest both in preserving the terrestrial carbon pool and in conserving biodiversity. In this perspective, we highlight that achieving mutual benefits between these aims is clearly promoted by congruence between biodiversity and carbon stocks in tropical latitudes (i.e. high carbon, high biodiversity systems), revealed by recent data and modeling advances, but that mechanisms behind this congruence are not obvious. Furthermore, key processes at subtropical and higher latitudes with less obvious links to biodiversity require policy attention. These processes include wildfire in the subtropics (high biodiversity, low-carbon systems), and ecosystem-level respiration and decomposition at boreal and polar latitudes (low biodiversity, high carbon systems). No clear global relationship between biodiversity and carbon sequestration is apparent, but this does not preclude positive relationships at local to regional scales. There is a growing understanding of the potential value of biodiversity in enhancing carbon management aims, but key knowledge gaps remain that prevent more mature policy development for their co-management.