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Carlos M Duarte - One of the best experts on this subject based on the ideXlab platform.
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habitat characteristics provide insights of carbon storage in Seagrass meadows
Marine Pollution Bulletin, 2018Co-Authors: Nuria Marba, Ines Mazarrasa, Carlos M Duarte, Jimena Sampervillarreal, Catherine E Lovelock, Oscar Serrano, Paul S Lavery, Jorge CortesAbstract:Abstract Seagrass meadows provide multiple ecosystem services, yet they are among the most threatened ecosystems on earth. Because of their role as carbon sinks, protection and restoration of Seagrass meadows contribute to climate change mitigation. Blue Carbon strategies aim to enhance CO2 sequestration and avoid greenhouse gasses emissions through the management of coastal vegetated ecosystems, including Seagrass meadows. The implementation of Blue Carbon strategies requires a good understanding of the habitat characteristics that influence Corg sequestration. Here, we review the existing knowledge on Blue Carbon research in Seagrass meadows to identify the key habitat characteristics that influence Corg sequestration in Seagrass meadows, those factors that threaten this function and those with unclear effects. We demonstrate that not all Seagrass habitats have the same potential, identify research priorities and describe the implications of the results found for the implementation and development of efficient Blue Carbon strategies based on Seagrass meadows.
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export from Seagrass meadows contributes to marine carbon sequestration
Frontiers in Marine Science, 2017Co-Authors: Carlos M Duarte, Dorte KrausejensenAbstract:Seagrasses export a substantial portion of their primary production, both in particulate and dissolved organic form, but the fate of this export production remains unaccounted for in terms of Seagrass carbon sequestration. Here we review available evidence on the fate of Seagrass carbon export to conclude that this represents a significant contribution to carbon sequestration, both in sediments outside Seagrass meadows and in the deep sea. The evidence presented implies that the contribution of Seagrass meadows to carbon sequestration has been underestimated by only including carbon burial within Seagrass sediments.
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impact of Seagrass loss and subsequent revegetation on carbon sequestration and stocks
Journal of Ecology, 2015Co-Authors: Nuria Marba, Gary A. Kendrick, Ariane Ariasortiz, Pere Masque, Ines Mazarrasa, Geoff R Bastyan, Jordi Garciaorellana, Carlos M DuarteAbstract:Summary Seagrass meadows are sites of high rates of carbon sequestration and they potentially support ‘blue carbon’ strategies to mitigate anthropogenic CO2 emissions. Current uncertainties on the fate of carbon stocks following the loss or revegetation of Seagrass meadows prevent the deployment of ‘blue carbon’ strategies. Here, we reconstruct the trajectories of carbon stocks associated with one of the longest monitored Seagrass restoration projects globally. We demonstrate that sediment carbon stocks erode following Seagrass loss and that revegetation projects effectively restore Seagrass carbon sequestration capacity. We combine carbon chronosequences with 210Pb dating of Seagrass sediments in a meadow that experienced losses until the end of 1980s and subsequent serial revegetation efforts. Inventories of excess 210Pb in Seagrass sediments revealed that its accumulation, and thus sediments, coincided with the presence of Seagrass vegetation. They also showed that the upper sediments eroded in areas that remained devoid of vegetation after Seagrass loss. Seagrass revegetation enhanced autochthonous and allochthonous carbon deposition and burial. Carbon burial rates increased with the age of the restored sites, and 18 years after planting, they were similar to that in continuously vegetated meadows (26.4 ± 0.8 gCorg m−2 year−1). Synthesis. The results presented here demonstrate that loss of Seagrass triggers the erosion of historic carbon deposits and that revegetation effectively restores Seagrass carbon sequestration capacity. Thus, conservation and restoration of Seagrass meadows are effective strategies for climate change mitigation.
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assessing the capacity of Seagrass meadows for carbon burial current limitations and future strategies
Ocean & Coastal Management, 2013Co-Authors: Nuria Marba, Carlos M Duarte, Hilary Kennedy, Iris E HendriksAbstract:Seagrass meadows support high primary production rates and their canopies are efficient at filtering particles out of their water column as well as in preventing resuspension of the sediments. In addition, decomposition rates in Seagrass sediments are slow, because of low nutrient concentration in Seagrass detritus and low oxygen concentration in Seagrass sediments. These characteristics result in high carbon burial rates in Seagrass meadows, which have the capacity to accumulate large stores of carbon in their sediments, raising the seafloor. Carbon fingerprinting techniques allow to calculate both the age of these deposits and, therefore, the rate of carbon burial and identify the contribution of carbon produced by the Seagrass. Yet, data on the regional cover and carbon stocks in Seagrass meadows is sparse for some regions, particularly the Indo-Pacific, Africa and South America. In addition, our understanding of the factors regulating the variability in carbon sink capacity among Seagrass meadows is limited. These gaps limit the capacity to formulate strategies to mitigate climate change based on the carbon sink capacity of Seagrass meadows. A research strategy needs be formulated to address these gaps and provide the necessary protocols to ensure the accountability of mitigation actions involving the conservation and restoration of Seagrass meadows.
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Seagrass sediments as a global carbon sink isotopic constraints
Global Biogeochemical Cycles, 2010Co-Authors: Hilary Kennedy, Nuria Marba, Carlos M Duarte, Jeff Beggins, James W Fourqurean, Marianne Holmer, Jack J MiddelburgAbstract:Seagrass meadows are highly productive habitats found along many of the world’scoastline, providing important services that support the overall functioning of the coastalzone. The organic carbon that accumulates in Seagrass meadows is derived not only fromSeagrass production but from the trapping of other particles, as the Seagrass canopiesfacilitate sedimentation and reduce resuspension. Here we provide a comprehensivesynthesis of the available data to obtain a better understanding of the relative contributionof Seagrass and other possible sources of organic matter that accumulate in the sedimentsof Seagrass meadows. The data set includes 219 paired analyses of the carbon isotopiccomposition of Seagrass leaves and sediments from 207 Seagrass sites at 88 locationsworldwide. Using a three source mixing model and literature values for putative sources,we calculate that the average proportional contribution of Seagrass to the surfacesediment organic carbon pool is ∼50%. When using the best available estimates ofcarbon burial rates in Seagrass meadows, our data indicate that between 41 and66 gC m
Peter I Macreadie - One of the best experts on this subject based on the ideXlab platform.
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high variability of blue carbon storage in Seagrass meadows at the estuary scale
Scientific Reports, 2020Co-Authors: Michael Rasheed, Paul H. York, Aurora M Ricart, Catherine Bryant, Daniel Ierodiaconou, Peter I MacreadieAbstract:Seagrass meadows are considered important natural carbon sinks due to their capacity to store organic carbon (Corg) in sediments. However, the spatial heterogeneity of carbon storage in Seagrass sediments needs to be better understood to improve accuracy of Blue Carbon assessments, particularly when strong gradients are present. We performed an intensive coring study within a sub-tropical estuary to assess the spatial variability in sedimentary Corg associated with Seagrasses, and to identify the key factors promoting this variability. We found a strong spatial pattern within the estuary, from 52.16 mg Corg cm−3 in Seagrass meadows in the upper parts, declining to 1.06 mg Corg cm−3 in Seagrass meadows at the estuary mouth, despite a general gradient of increasing Seagrass cover and Seagrass habitat extent in the opposite direction. The sedimentary Corg underneath Seagrass meadows came principally from allochthonous (non-Seagrass) sources (~70–90 %), while the contribution of Seagrasses was low (~10–30 %) throughout the entire estuary. Our results showed that Corg stored in sediments of Seagrass meadows can be highly variable within an estuary, attributed largely to accumulation of fine sediments and inputs of allochthonous sources. Local features and the existence of spatial gradients must be considered in Blue Carbon estimates in coastal ecosystems.
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sediment microbes mediate the impact of nutrient loading on blue carbon sequestration by mixed Seagrass meadows
Science of The Total Environment, 2017Co-Authors: Songlin Liu, Zhijian Jiang, Jingping Zhang, Xiaoping Huang, Peter I MacreadieAbstract:Recent studies have reported significant variability in sediment organic carbon (SOC) storage capacity among Seagrass species, but the factors driving this variability are poorly understood, limiting our ability to make informed decisions about which Seagrass types are optimal for carbon offsetting and why. Here we show that differences in SOC storage capacity among species within the same geomorphic environment can be explained (in part) by below-ground processes in response to nutrient load; specifically, differences in the activity of microbes harboured by morphologically-different Seagrass species. We found that increasing nutrient load enhanced the relative contribution of Seagrass and algal sources to SOC pools, boosting sediment microbial biomass and extracellular enzyme activity within mixed Seagrass meadows composed of Thalassia hemprichii and Enhalus acoroides, and thus possibly weaken the Seagrass blue carbon sequestration capacity. The relative contribution of Seagrass plant material to sediment bacterial organic carbon (BOC) and the influencing SOC-decomposing enzymes in E. acoroides meadows were half that of T. hemprichii meadows living side-by-side, even though the mixed Seagrass meadows received SOC from the same sources. Overall this research suggests that microbial activity can vary significantly among Seagrass species, thereby causing fine-scale (within-meadow) variability in SOC sequestration capacity in response to nutrient load.
Nuria Marba - One of the best experts on this subject based on the ideXlab platform.
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habitat characteristics provide insights of carbon storage in Seagrass meadows
Marine Pollution Bulletin, 2018Co-Authors: Nuria Marba, Ines Mazarrasa, Carlos M Duarte, Jimena Sampervillarreal, Catherine E Lovelock, Oscar Serrano, Paul S Lavery, Jorge CortesAbstract:Abstract Seagrass meadows provide multiple ecosystem services, yet they are among the most threatened ecosystems on earth. Because of their role as carbon sinks, protection and restoration of Seagrass meadows contribute to climate change mitigation. Blue Carbon strategies aim to enhance CO2 sequestration and avoid greenhouse gasses emissions through the management of coastal vegetated ecosystems, including Seagrass meadows. The implementation of Blue Carbon strategies requires a good understanding of the habitat characteristics that influence Corg sequestration. Here, we review the existing knowledge on Blue Carbon research in Seagrass meadows to identify the key habitat characteristics that influence Corg sequestration in Seagrass meadows, those factors that threaten this function and those with unclear effects. We demonstrate that not all Seagrass habitats have the same potential, identify research priorities and describe the implications of the results found for the implementation and development of efficient Blue Carbon strategies based on Seagrass meadows.
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impact of Seagrass loss and subsequent revegetation on carbon sequestration and stocks
Journal of Ecology, 2015Co-Authors: Nuria Marba, Gary A. Kendrick, Ariane Ariasortiz, Pere Masque, Ines Mazarrasa, Geoff R Bastyan, Jordi Garciaorellana, Carlos M DuarteAbstract:Summary Seagrass meadows are sites of high rates of carbon sequestration and they potentially support ‘blue carbon’ strategies to mitigate anthropogenic CO2 emissions. Current uncertainties on the fate of carbon stocks following the loss or revegetation of Seagrass meadows prevent the deployment of ‘blue carbon’ strategies. Here, we reconstruct the trajectories of carbon stocks associated with one of the longest monitored Seagrass restoration projects globally. We demonstrate that sediment carbon stocks erode following Seagrass loss and that revegetation projects effectively restore Seagrass carbon sequestration capacity. We combine carbon chronosequences with 210Pb dating of Seagrass sediments in a meadow that experienced losses until the end of 1980s and subsequent serial revegetation efforts. Inventories of excess 210Pb in Seagrass sediments revealed that its accumulation, and thus sediments, coincided with the presence of Seagrass vegetation. They also showed that the upper sediments eroded in areas that remained devoid of vegetation after Seagrass loss. Seagrass revegetation enhanced autochthonous and allochthonous carbon deposition and burial. Carbon burial rates increased with the age of the restored sites, and 18 years after planting, they were similar to that in continuously vegetated meadows (26.4 ± 0.8 gCorg m−2 year−1). Synthesis. The results presented here demonstrate that loss of Seagrass triggers the erosion of historic carbon deposits and that revegetation effectively restores Seagrass carbon sequestration capacity. Thus, conservation and restoration of Seagrass meadows are effective strategies for climate change mitigation.
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assessing the capacity of Seagrass meadows for carbon burial current limitations and future strategies
Ocean & Coastal Management, 2013Co-Authors: Nuria Marba, Carlos M Duarte, Hilary Kennedy, Iris E HendriksAbstract:Seagrass meadows support high primary production rates and their canopies are efficient at filtering particles out of their water column as well as in preventing resuspension of the sediments. In addition, decomposition rates in Seagrass sediments are slow, because of low nutrient concentration in Seagrass detritus and low oxygen concentration in Seagrass sediments. These characteristics result in high carbon burial rates in Seagrass meadows, which have the capacity to accumulate large stores of carbon in their sediments, raising the seafloor. Carbon fingerprinting techniques allow to calculate both the age of these deposits and, therefore, the rate of carbon burial and identify the contribution of carbon produced by the Seagrass. Yet, data on the regional cover and carbon stocks in Seagrass meadows is sparse for some regions, particularly the Indo-Pacific, Africa and South America. In addition, our understanding of the factors regulating the variability in carbon sink capacity among Seagrass meadows is limited. These gaps limit the capacity to formulate strategies to mitigate climate change based on the carbon sink capacity of Seagrass meadows. A research strategy needs be formulated to address these gaps and provide the necessary protocols to ensure the accountability of mitigation actions involving the conservation and restoration of Seagrass meadows.
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Seagrass sediments as a global carbon sink isotopic constraints
Global Biogeochemical Cycles, 2010Co-Authors: Hilary Kennedy, Nuria Marba, Carlos M Duarte, Jeff Beggins, James W Fourqurean, Marianne Holmer, Jack J MiddelburgAbstract:Seagrass meadows are highly productive habitats found along many of the world’scoastline, providing important services that support the overall functioning of the coastalzone. The organic carbon that accumulates in Seagrass meadows is derived not only fromSeagrass production but from the trapping of other particles, as the Seagrass canopiesfacilitate sedimentation and reduce resuspension. Here we provide a comprehensivesynthesis of the available data to obtain a better understanding of the relative contributionof Seagrass and other possible sources of organic matter that accumulate in the sedimentsof Seagrass meadows. The data set includes 219 paired analyses of the carbon isotopiccomposition of Seagrass leaves and sediments from 207 Seagrass sites at 88 locationsworldwide. Using a three source mixing model and literature values for putative sources,we calculate that the average proportional contribution of Seagrass to the surfacesediment organic carbon pool is ∼50%. When using the best available estimates ofcarbon burial rates in Seagrass meadows, our data indicate that between 41 and66 gC m
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scaling of ramet size and spacing in Seagrasses implications for stand development
Aquatic Botany, 2003Co-Authors: Nuria Marba, Carlos M DuarteAbstract:The scaling between shoot mass and spacer length was examined across 23 Seagrass species by compiling field and literature data on architectural and stand features. The distance between shoots programmed in Seagrass architecture was scaled at the 0.24 power of shoot mass. The predicted distance between neighboring shoots resulting from the scaling relationship investigated was compared with the spacing observed in 79 crowded natural Seagrass stands. Seagrass architecture predicted 50% of the variability of the distance between neighbors observed in natural stands. Moreover, the growth programme of Seagrass species predicted 29% of the variance of maximum aboveground biomass developed by Seagrass meadows. The close agreement between the shoot density and biomass developed by closed natural stands and that predicted from Seagrass architecture suggested that the upper limit to density and aboveground biomass, such as that defined by the self-thinning law, is already imprinted within the basic architecture of Seagrasses (i.e. spacer length in between consecutive shoots).
Gary A. Kendrick - One of the best experts on this subject based on the ideXlab platform.
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impact of Seagrass loss and subsequent revegetation on carbon sequestration and stocks
Journal of Ecology, 2015Co-Authors: Nuria Marba, Gary A. Kendrick, Ariane Ariasortiz, Pere Masque, Ines Mazarrasa, Geoff R Bastyan, Jordi Garciaorellana, Carlos M DuarteAbstract:Summary Seagrass meadows are sites of high rates of carbon sequestration and they potentially support ‘blue carbon’ strategies to mitigate anthropogenic CO2 emissions. Current uncertainties on the fate of carbon stocks following the loss or revegetation of Seagrass meadows prevent the deployment of ‘blue carbon’ strategies. Here, we reconstruct the trajectories of carbon stocks associated with one of the longest monitored Seagrass restoration projects globally. We demonstrate that sediment carbon stocks erode following Seagrass loss and that revegetation projects effectively restore Seagrass carbon sequestration capacity. We combine carbon chronosequences with 210Pb dating of Seagrass sediments in a meadow that experienced losses until the end of 1980s and subsequent serial revegetation efforts. Inventories of excess 210Pb in Seagrass sediments revealed that its accumulation, and thus sediments, coincided with the presence of Seagrass vegetation. They also showed that the upper sediments eroded in areas that remained devoid of vegetation after Seagrass loss. Seagrass revegetation enhanced autochthonous and allochthonous carbon deposition and burial. Carbon burial rates increased with the age of the restored sites, and 18 years after planting, they were similar to that in continuously vegetated meadows (26.4 ± 0.8 gCorg m−2 year−1). Synthesis. The results presented here demonstrate that loss of Seagrass triggers the erosion of historic carbon deposits and that revegetation effectively restores Seagrass carbon sequestration capacity. Thus, conservation and restoration of Seagrass meadows are effective strategies for climate change mitigation.
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spatial patterns in fish herbivory in a temperate australian Seagrass meadow
Estuarine Coastal and Shelf Science, 2011Co-Authors: K S White, M Westera, Gary A. KendrickAbstract:Abstract Seagrass grazing by fish was measured in a large Seagrass-dominated temperate bay (Geographe Bay, Western Australia) to examine whether: (1) Seagrass herbivory occurs; (2) the level of herbivory is influenced by nitrogen in Seagrass leaves; and (3) how herbivory and herbivorous fish communities vary with water depth and Seagrass species. Species and abundance of fish and herbivore bite marks on Seagrass leaves were recorded from diver surveys of 23 sites of varying depth ranging from 1 m to 18 m. Posidonia sinuosa , Posidonia coriacea , Amphibolis griffithii , and Amphibolis antarctica Seagrass leaves were collected, dried and analysed for total nitrogen. Evidence for low levels of Seagrass grazing was found at over half the sites surveyed, though high levels of grazing were recorded at only one site. An east–west pattern was observed in the location of grazed sites and of herbivorous fish species that corresponded with the general prevalence of patch reefs, indicating that reef associated fish assemblages may be responsible for the observed grazing. Total nitrogen was elevated in Seagrass leaves associated with drains, although increased nitrogen was not associated with increased grazing. While grazing was recorded in this temperate Seagrass meadow, the abundance of herbivorous fish was low and the amount of biomass removed by them was small compared to the balance of the meadow remaining, and to Seagrass grazing studies elsewhere.
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trophic transfers from Seagrass meadows subsidize diverse marine and terrestrial consumers
Ecosystems, 2008Co-Authors: Kenneth L Heck, Gary A. Kendrick, Carlos M Duarte, Robert J Orth, Tim J B Carruthers, Randall A Hughes, Susan W WilliamsAbstract:In many coastal locations, Seagrass meadows are part of a greater seascape that includes both marine and terrestrial elements, each linked to the other via the foraging patterns of consumers (both predators and herbivores), and the passive drift of Seagrass propagules, leaves, roots and rhizomes, and Seagrass-associated macroalgal detritus. With Seagrasses declining in many regions, the linkages between Seagrass meadows and other habitats are being altered and diminished. Thus, it is timely to summarize what is known about the prevalence and magnitude of cross-habitat exchanges of Seagrass-derived energy and materials, and to increase awareness of the importance of Seagrasses to adjacent and even distant habitats. To do so we examined the literature on the extent and importance of exchanges of biomass between Seagrass meadows and other habitats, both in the form of exported Seagrass biomass as well as transfers of animal biomass via migration. Data were most abundant for Caribbean coral reefs and Australian beaches, and organisms for which there were quantitative estimates included Caribbean fishes and North American migratory waterfowl. Overall, data from the studies we reviewed clearly showed that Seagrass ecosystems provide a large subsidy to both near and distant locations through the export of particulate organic matter and living plant and animal biomass. The consequences of continuing Seagrass decline thus extend far beyond the areas where Seagrasses grow.
Jimena Sampervillarreal - One of the best experts on this subject based on the ideXlab platform.
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habitat characteristics provide insights of carbon storage in Seagrass meadows
Marine Pollution Bulletin, 2018Co-Authors: Nuria Marba, Ines Mazarrasa, Carlos M Duarte, Jimena Sampervillarreal, Catherine E Lovelock, Oscar Serrano, Paul S Lavery, Jorge CortesAbstract:Abstract Seagrass meadows provide multiple ecosystem services, yet they are among the most threatened ecosystems on earth. Because of their role as carbon sinks, protection and restoration of Seagrass meadows contribute to climate change mitigation. Blue Carbon strategies aim to enhance CO2 sequestration and avoid greenhouse gasses emissions through the management of coastal vegetated ecosystems, including Seagrass meadows. The implementation of Blue Carbon strategies requires a good understanding of the habitat characteristics that influence Corg sequestration. Here, we review the existing knowledge on Blue Carbon research in Seagrass meadows to identify the key habitat characteristics that influence Corg sequestration in Seagrass meadows, those factors that threaten this function and those with unclear effects. We demonstrate that not all Seagrass habitats have the same potential, identify research priorities and describe the implications of the results found for the implementation and development of efficient Blue Carbon strategies based on Seagrass meadows.
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organic carbon in Seagrass sediments is influenced by Seagrass canopy complexity turbidity wave height and water depth
Limnology and Oceanography, 2016Co-Authors: Jimena Sampervillarreal, Catherine E Lovelock, Megan I Saunders, Chris Roelfsema, Peter J MumbyAbstract:Seagrass meadows are important marine carbon sinks, yet they are threatened and declining worldwide. Seagrass management and conservation requires adequate understanding of the physical and biological factors determining carbon content in Seagrass sediments. Here, we identified key factors that influence carbon content in Seagrass meadows across several environmental gradients in Moreton Bay, SE Queensland. Sampling was conducted in two regions: (1) Canopy Complexity, 98 sites on the Eastern Banks, where Seagrass canopy structure and species composition varied while turbidity was consistently low; and (2) Turbidity Gradient, 11 locations across the entire bay, where turbidity varied among sampling locations. Sediment organic carbon content and Seagrass structural complexity (shoot density, leaf area, and species specific characteristics) were measured from shallow sediment and Seagrass biomass cores at each location, respectively. Environmental data were obtained from empirical measurements (water quality) and models (wave height). The key factors influencing carbon content in Seagrass sediments were Seagrass structural complexity, turbidity, water depth, and wave height. In the Canopy Complexity region, carbon content was higher for shallower sites and those with higher Seagrass structural complexity. When turbidity varied along the Turbidity Gradient, carbon content was higher at sites with high turbidity. In both regions carbon content was consistently higher in sheltered areas with lower wave height. Seagrass canopy structure, water depth, turbidity, and hydrodynamic setting of Seagrass meadows should therefore be considered in conservation and management strategies that aim to maximize sediment carbon content.
