The term Blue Carbon (BC) was first coined a decade ago to describe the disproportionately large contribution of coastal vegetated ecosystems to global carbon sequestration. The role of BC in climate change mitigation and adaptation has now reached international prominence. To help prioritise future research, we assembled leading experts in the field to agree upon the top-ten pending questions in BC science. Understanding how climate change affects carbon accumulation in mature BC ecosystems and during their restoration was a high priority. Controversial questions included the role of carbonate and macroalgae in BC cycling, and the degree to which greenhouse gases are released following disturbance of BC ecosystems. Scientists seek improved precision of the extent of BC ecosystems; techniques to determine BC provenance; understanding of the factors that influence sequestration in BC ecosystems, with the corresponding value of BC; and the management actions that are effective in enhancing this value. Overall this overview provides a comprehensive road map for the coming decades on future research in BC science.

Accounting guidelines exist for the recording of carbon flows in terrestrial and coastal ecosystems. Shelf sea sediments, while considered an important carbon store, have yet to receive comparable scrutiny. Here, we explore whether effective management of carbon stocks accumulating in shelf seas could contribute towards a nation’s greenhouse gas emissions reduction targets. We review the complexities of carbon transport and fate in shelf seas, and the geopolitical challenges of carbon accounting in climate governance because of the transboundary nature of carbon flows in the marine environment. New international accounting guidance and governance frameworks are needed to prompt climate action.

Cinnirella, S., R. Sardà, J. Suárez de Vivero, R. Brennan, A. Barausse, J. Icely, T. Luisetti, D. March, C. Murciano, A. Newton, T. O'Higgins, L. Palmeri, M. Palmieri, P. Raux, S. Rees, J. Albaigés, N. Pirrone, and K. Turner. 2014. Steps toward a shared governance response for achieving Good Environmental Status in the Mediterranean Sea. Ecology and Society 19(4): 47.http://dx.doi.org/10.5751/ES-07065-190447

Natural capital accounting requires exchange rather than welfare values, but lack of data and standards have encouraged practitioners to use different approaches (e.g. simple lookup table vs spatial modeling approaches). In this paper, we demonstrate how choice modeling data can provide simulated exchange values which are more robust than simple (fast track) valuation approaches for natural capital accounting. A survey of East of England residents collected the preferences for saltmarsh management and simulated exchange values, coherently linked with the ecosystem conditions. This approach is more informative for environmental local planning purposes. We claim that expanding the set of tools available for natural capital accounting can enhance management of ecosystem services and policy decision making.