Recent research has highlighted the valuable role that coastal and marine ecosystems play in sequestering carbon dioxide (CO2). The carbon (C) sequestered in vegetated coastal ecosystems, specifically mangrove forests, seagrass beds, and salt marshes, has been termed “blue carbon”. Although their global area is one to two orders of magnitude smaller than that of terrestrial forests, the contribution of vegetated coastal habitats per unit area to long‐term C sequestration is much greater, in part because of their efficiency in trapping suspended matter and associated organic C during tidal inundation. Despite the value of mangrove forests, seagrass beds, and salt marshes in sequestering C, and the other goods and services they provide, these systems are being lost at critical rates and action is urgently needed to prevent further degradation and loss. Recognition of the C sequestration value of vegetated coastal ecosystems provides a strong argument for their protection and restoration; however, it is necessary to improve scientific understanding of the underlying mechanisms that control C sequestration in these ecosystems. Here, we identify key areas of uncertainty and specific actions needed to address them.

The massive scale of the 1997–1998 El Niño–associated coral bleaching event underscores the need for strategies to mitigate biodiversity losses resulting from temperature‐induced coral mortality. As baseline sea surface temperatures continue to rise, climate change may represent the single greatest threat to coral reefs worldwide. In response, one strategy might be to identify ( 1 ) specific reef areas where natural environmental conditions are likely to result in low or negligible temperature‐related bleaching and mortality ( i.e., areas of natural “resistance” to bleaching ) and ( 2 ) reef areas where environmental conditions are likely to result in maximum recovery of reef communities after bleaching mortality has occurred ( i.e., areas of natural community “resilience” ). These “target areas,” where environmental conditions appear to boost resistance and resilience during and after large‐scale bleaching events, could then be incorporated into strategic networks of marine protected areas designed to maximize conservation of global coral reef biodiversity. Based on evidence from the literature and systematically compiled observations from researchers in the field, this paper identifies likely environmental correlates of resistance and resilience to coral bleaching, including factors that reduce temperature stress, enhance water movement, decrease light stress, correlate with physiological tolerance, and provide physical or biological enhancement of recovery potential. As a tool for identifying reef areas that are likely to be most robust in the face of continuing climate change and for determining priority areas for reducing direct anthropogenic impacts, this information has important implications for coral reef conservation and management.

Principles for designing marine protected area (MPA) networks that address social, economic, and biological criteria are well established in the scientific literature. Climate change represents a new and serious threat to marine ecosystems, but, to date, few studies have specifically considered how to design MPA networks to be resilient to this emerging threat. Here, we compile the best available information on MPA network design and supplement it with specific recommendations for building resilience into these networks. We provide guidance on size, spacing, shape, risk spreading (representation and replication), critical areas, connectivity, and maintaining ecosystem function to help MPA planners and managers design MPA networks that are more robust in the face of climate‐change impacts.

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