TY - BOOK
T1 - A Research Review of Interventions to Increase the Persistence and Resilience of Coral Reefs
AU - National Academies of Sciences, Engineering, and Medicine
AU - Division on Earth and Life Studies
AU - Ocean Studies Board
AU - Board on Life Sciences
AU - Committee on Interventions to Increase the Resilience of Coral Reefs
AU - Logan, Cheryl
PY - 2019/5
Y1 - 2019/5
N2 - Coral reef declines have been recorded for all major tropical ocean basins since the 1980s, averaging approximately 30-50% reductions in reef cover globally. These losses are a result of numerous problems, including habitat destruction, pollution, overfishing, disease, and climate change. Greenhouse gas emissions and the associated increases in ocean temperature and carbon dioxide (CO2) concentrations have been implicated in increased reports of coral bleaching, disease outbreaks, and ocean acidification (OA). Back-to-back mass coral bleaching events in 2015-2016 and 2017 have resulted in dramatic coral die-offs. For the hundreds of millions of people who depend on reefs for food or livelihoods, the thousands of communities that depend on reefs for wave protection, the people whose cultural practices are tied to reef resources, and the many economies that depend on reefs for fisheries or tourism, the health and maintenance of this major global ecosystem is crucial. While abatement of local and regional stressors will continue to be critical to coral reef persistence, these efforts on their own will not be sufficient to address the impacts of climate change. The recent pan-tropical bleaching events showed that remote coral reefs under minimal influence from human activities bleached as severely as reefs exposed to multiple stressors such as pollution and overfishing. Reduction and mitigation of carbon emissions will be required for successful global management of marine ecosystems. But even with such reductions, committed warming from the current accumulation of greenhouse gases is expected to expose the majority of the world’s reefs to bleaching conditions annually by 2050. In the face of these predictions, a growing body of research on coral physiology, ecology, molecular biology, and responses to stress has revealed potential tools to increase coral resilience. Some of this knowledge is poised to provide practical interventions in the short-term, whereas other discoveries are poised to facilitate research that may later open the doors to additional interventions. This committee has been tasked with reviewing the state of science on genetic, ecological, and environmental interventions meant to enhance the persistence and resilience of coral reefs. The complex nature of corals and their associated microbiome (the holobiont; including symbiotic algal, prokaryotic, fungal, and viral components) lends itself to a wide range of possible approaches. In this first report, the committee provides a summary of currently available information on the range of interventions present in the scientific literature. This report provides a basis for the remainder of the committee’s task to be covered in the final report. Specifically, the task in this report is to (the full task can be found in Box 1.2): Review and summarize scientific research on a range of intervention strategies, either designed specifically for coral or with the potential to be applied to coral, including evaluation of the state of readiness. Strategies of interest include, but are not limited to, stress-hardening, translocation of non-native coral stocks or species, manipulation of symbiotic partnerships within the coral holobiont, managed selection, genetic modification, and to the extent possible, proposed engineering solutions to promote reef persistence, such as shading/cooling during bleaching events. Resilience refers to the overall ability of individuals, populations, or communities to respond positively after disturbance, restoring some part of their original state. As a concept, resilience can be applied to different levels of ecosystems. For example, individual organisms can show physiological resilience via survival, sustained growth, and/or reproduction (fitness). Populations can show resilience through the ability to recruit new individuals after a disturbance. Communities can show resilience in ecosystem traits such as productivity, diversity, trophic linkages, or sustained biomass through shifts in species composition. This report is structured to address the interventions that have the potential to increase resilience at each of these scales. The report also includes consideration of interventions that could promote persistence of coral reefs although they may not improve resilience, particularly those that reduce exposure to environmental stress, as an important part of the toolkit of responses to deteriorating environmental conditions. For each intervention, its attributes, current feasibility, potential scale, limitations, and risks are reviewed. Strong attention has been paid to similar efforts under way in other countries that are home to extensive reefs and strong research capacity, particularly in Australia. Attitudes about the need for novel interventions are coalescing among managers and scientists, and the core technologies needed to enact such interventions are quickly advancing. As such, this report is a benchmark that reflects current research, identifying efforts that range from those potentially feasible now to those that offer promise on a decadal time scale. Even with these interventions, reefs at the end of this century will not look like the reefs at the beginning. The goal has been to lay out the toolbox that might allow coral reefs to persist, stabilizing the value of these ecosystems to human well-being, national economies, and future wonder.
AB - Coral reef declines have been recorded for all major tropical ocean basins since the 1980s, averaging approximately 30-50% reductions in reef cover globally. These losses are a result of numerous problems, including habitat destruction, pollution, overfishing, disease, and climate change. Greenhouse gas emissions and the associated increases in ocean temperature and carbon dioxide (CO2) concentrations have been implicated in increased reports of coral bleaching, disease outbreaks, and ocean acidification (OA). Back-to-back mass coral bleaching events in 2015-2016 and 2017 have resulted in dramatic coral die-offs. For the hundreds of millions of people who depend on reefs for food or livelihoods, the thousands of communities that depend on reefs for wave protection, the people whose cultural practices are tied to reef resources, and the many economies that depend on reefs for fisheries or tourism, the health and maintenance of this major global ecosystem is crucial. While abatement of local and regional stressors will continue to be critical to coral reef persistence, these efforts on their own will not be sufficient to address the impacts of climate change. The recent pan-tropical bleaching events showed that remote coral reefs under minimal influence from human activities bleached as severely as reefs exposed to multiple stressors such as pollution and overfishing. Reduction and mitigation of carbon emissions will be required for successful global management of marine ecosystems. But even with such reductions, committed warming from the current accumulation of greenhouse gases is expected to expose the majority of the world’s reefs to bleaching conditions annually by 2050. In the face of these predictions, a growing body of research on coral physiology, ecology, molecular biology, and responses to stress has revealed potential tools to increase coral resilience. Some of this knowledge is poised to provide practical interventions in the short-term, whereas other discoveries are poised to facilitate research that may later open the doors to additional interventions. This committee has been tasked with reviewing the state of science on genetic, ecological, and environmental interventions meant to enhance the persistence and resilience of coral reefs. The complex nature of corals and their associated microbiome (the holobiont; including symbiotic algal, prokaryotic, fungal, and viral components) lends itself to a wide range of possible approaches. In this first report, the committee provides a summary of currently available information on the range of interventions present in the scientific literature. This report provides a basis for the remainder of the committee’s task to be covered in the final report. Specifically, the task in this report is to (the full task can be found in Box 1.2): Review and summarize scientific research on a range of intervention strategies, either designed specifically for coral or with the potential to be applied to coral, including evaluation of the state of readiness. Strategies of interest include, but are not limited to, stress-hardening, translocation of non-native coral stocks or species, manipulation of symbiotic partnerships within the coral holobiont, managed selection, genetic modification, and to the extent possible, proposed engineering solutions to promote reef persistence, such as shading/cooling during bleaching events. Resilience refers to the overall ability of individuals, populations, or communities to respond positively after disturbance, restoring some part of their original state. As a concept, resilience can be applied to different levels of ecosystems. For example, individual organisms can show physiological resilience via survival, sustained growth, and/or reproduction (fitness). Populations can show resilience through the ability to recruit new individuals after a disturbance. Communities can show resilience in ecosystem traits such as productivity, diversity, trophic linkages, or sustained biomass through shifts in species composition. This report is structured to address the interventions that have the potential to increase resilience at each of these scales. The report also includes consideration of interventions that could promote persistence of coral reefs although they may not improve resilience, particularly those that reduce exposure to environmental stress, as an important part of the toolkit of responses to deteriorating environmental conditions. For each intervention, its attributes, current feasibility, potential scale, limitations, and risks are reviewed. Strong attention has been paid to similar efforts under way in other countries that are home to extensive reefs and strong research capacity, particularly in Australia. Attitudes about the need for novel interventions are coalescing among managers and scientists, and the core technologies needed to enact such interventions are quickly advancing. As such, this report is a benchmark that reflects current research, identifying efforts that range from those potentially feasible now to those that offer promise on a decadal time scale. Even with these interventions, reefs at the end of this century will not look like the reefs at the beginning. The goal has been to lay out the toolbox that might allow coral reefs to persist, stabilizing the value of these ecosystems to human well-being, national economies, and future wonder.
UR - https://www.mendeley.com/catalogue/36d33455-9df8-35e4-8ac1-002ad2c0a94f/
U2 - 10.17226/25279
DO - 10.17226/25279
M3 - Book
BT - A Research Review of Interventions to Increase the Persistence and Resilience of Coral Reefs
PB - National Academies Press
ER -