1.Introduction Since the Industrial Revolution,oceans have absorbed approximately one-third of the carbon dioxide(CO_(2)) released by human activities and have maintained their capacity for CO_(2) uptake.The biologica...1.Introduction Since the Industrial Revolution,oceans have absorbed approximately one-third of the carbon dioxide(CO_(2)) released by human activities and have maintained their capacity for CO_(2) uptake.The biological carbon pump(BCP)(Volk and Hoffert,1985)drives particulate organic carbon(POC),which is generated in the surface ocean by phytoplankton photosynthesis,into the interior of the ocean through the gravitational settling of POC and vertical migration of zooplankton.展开更多
Against the background of realizing the goal of“carbon peaking and carbon neutrality”,using basaltic rocks for carbon mineralization is one of the most promising approaches to reduce the rise in atmospheric CO_(2)co...Against the background of realizing the goal of“carbon peaking and carbon neutrality”,using basaltic rocks for carbon mineralization is one of the most promising approaches to reduce the rise in atmospheric CO_(2)concentrations.This study conducted a series of experiments to assess carbon mineralization in nine basalt samples from the main terrestrial basalt reservoirs in China within CO_(2)-H2O/brine-rock systems at low temperatures(≤35℃).The results indicate that the secondary carbonates formed in the CO_(2)-H2O/brine-basalt system are predominantly calcite rather than Mg-carbonate minerals at low temperatures(≤35℃).Hence,at low temperatures(≤35℃),basalt rich in Ca-bearing minerals promotes the formation of stable carbonate minerals more effectively than basalt containing Mg-bearing minerals.Furthermore,under conditions of low temperatures(≤35℃)and pressures of approximately 3 MPa,the results suggest that alkaline olivine basalt,with a higher content of Ca-minerals and typical alkaline minerals(nepheline and Na-sanidine),exhibits the highest pH value and the highest amount of calcite.Hence,the alkaline minerals,nepheline and Na-sanidine,serve as pH buffers to increase the pH and promote the precipitation of calcite within CO_(2)-H2O-basalt systems at low temperatures(≤35℃).Among the nine evaluated basalts,basalt from the Shandong Linqu-Changle volcanic basin exhibits the highest rate of carbon mineralization at low temperatures(≤35℃).Hence,Cenozoic alkaline olivine basalt from Shandong Linqu-Changle volcanic basin is one of the most promising basalt reservoirs in China for future in-situ carbonation.As for ex-situ carbonation,compared with olivine,diopside or Ca-plagioclase may be more appropriate for increasing ocean negative emissions.展开更多
To achieve the Paris Agreement,China pledged to become“Carbon Neutral”by the 2060s.In addition to massive decarbonization,this would require significant changes in ecosystems toward negative CO_(2)emissions.The abil...To achieve the Paris Agreement,China pledged to become“Carbon Neutral”by the 2060s.In addition to massive decarbonization,this would require significant changes in ecosystems toward negative CO_(2)emissions.The ability of coastal blue carbon ecosystems(BCEs),including mangrove,salt marsh,and seagrass meadows,to sequester large amounts of CO_(2)makes their conservation and restoration an important“nature-based solution(NbS)”for climate adaptation and mitigation.In this review,we examine how BCEs in China can contribute to climate mitigation.On the national scale,the BCEs in China store up to 118 Tg C across a total area of 1,440,377 ha,including over 75%as unvegetated tidal flats.The annual sedimental C burial of these BCEs reaches up to 2.06 Tg C year^(−1),of which most occurs in salt marshes and tidal flats.The lateral C flux of mangroves and salt marshes contributes to 1.17 Tg C year^(−1)along the Chinese coastline.Conservation and restoration of BCEs benefit climate change mitigation and provide other ecological services with a value of$32,000 ha^(−1)year^(−1).The potential practices and technologies that can be implemented in China to improve BCE C sequestration,including their constraints and feasibility,are also outlined.Future directions are suggested to improve blue carbon estimates on aerial extent,carbon stocks,sequestration,and mitigation potential.Restoring and preserving BCEs would be a cost-effective step to achieve Carbon Neutral by 2060 in China despite various barriers that should be removed.展开更多
Macroalgal mariculture is gaining global attention to achieve carbon neutrality due to its important contribution to ocean carbon sequestration.However,some wild macroalgal species(e.g.,Sargassum and Ulva prolifera)ex...Macroalgal mariculture is gaining global attention to achieve carbon neutrality due to its important contribution to ocean carbon sequestration.However,some wild macroalgal species(e.g.,Sargassum and Ulva prolifera)exhibit strong environmental adaptability and can cause large-scale,recurrent blooms in global oceans,fueled by rising atmospheric CO_(2) levels and coastal eutrophication.Notably,massive Ulva prolifera green tides have occurred annually in the Yellow Sea for the past 17 consecutive years.At the late blooming stage,millions of tons of U.prolifera naturally sink to the shallow seafloor.The subsequent intense microbial aerobic degradation of sinking macroalgae results in coastal hypoxia and acidification,with most of the macroalgal carbon returning to the atmosphere.Preventing or reducing the intense degradation of massive sinking U.prolifera could enable more macroalgal carbon storage in the ocean in the long term and alleviate the harmful effects of green tide.Thus,ecological disasters from macroalgal blooms may be transformed into useful natural platforms to increase ocean carbon sequestration.We propose an integrated strategy using environmentally friendly minerals(e.g.,montmorillonite and calcium carbonate)and coagulants(e.g.,polyaluminum chloride),along with natural algicidal bacteria or substances,to induce rapid flocculation and sedimentation of blooming macroalgae,reduce the degradation of sinking macroalgae and its negative environmental impacts,and minimize the generation of macroalgal propagules or seeds and the potential risk for future green tide outbreaks.This integrated approach is potentially a promising approach to tap the carbon sequestration potential of macroalgal blooms to mitigate climate change.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.42188102&42206120)the Guangdong Major Project of Basic and Applied Basic Research(Grant No.2023B0303000017)+1 种基金the Innovation Team Project of Universities in Guangdong Province(Grant No.2023KCXTD028)the Ocean Negative Carbon Emissions(ONCE)program。
文摘1.Introduction Since the Industrial Revolution,oceans have absorbed approximately one-third of the carbon dioxide(CO_(2)) released by human activities and have maintained their capacity for CO_(2) uptake.The biological carbon pump(BCP)(Volk and Hoffert,1985)drives particulate organic carbon(POC),which is generated in the surface ocean by phytoplankton photosynthesis,into the interior of the ocean through the gravitational settling of POC and vertical migration of zooplankton.
基金funded by National Natural Science Foundation of China(General Program No.41872219 and Grant No.42303052)the National Key R&D Program of China(No.2023YFE0120500)+1 种基金funded by the Major Project of Inner Mongolia Science and Technology,China(Grant No.2021ZD0034)supported by Science and Technology Plan Projects in Shaanxi Province,China(No.2023-JC-YB-236).
文摘Against the background of realizing the goal of“carbon peaking and carbon neutrality”,using basaltic rocks for carbon mineralization is one of the most promising approaches to reduce the rise in atmospheric CO_(2)concentrations.This study conducted a series of experiments to assess carbon mineralization in nine basalt samples from the main terrestrial basalt reservoirs in China within CO_(2)-H2O/brine-rock systems at low temperatures(≤35℃).The results indicate that the secondary carbonates formed in the CO_(2)-H2O/brine-basalt system are predominantly calcite rather than Mg-carbonate minerals at low temperatures(≤35℃).Hence,at low temperatures(≤35℃),basalt rich in Ca-bearing minerals promotes the formation of stable carbonate minerals more effectively than basalt containing Mg-bearing minerals.Furthermore,under conditions of low temperatures(≤35℃)and pressures of approximately 3 MPa,the results suggest that alkaline olivine basalt,with a higher content of Ca-minerals and typical alkaline minerals(nepheline and Na-sanidine),exhibits the highest pH value and the highest amount of calcite.Hence,the alkaline minerals,nepheline and Na-sanidine,serve as pH buffers to increase the pH and promote the precipitation of calcite within CO_(2)-H2O-basalt systems at low temperatures(≤35℃).Among the nine evaluated basalts,basalt from the Shandong Linqu-Changle volcanic basin exhibits the highest rate of carbon mineralization at low temperatures(≤35℃).Hence,Cenozoic alkaline olivine basalt from Shandong Linqu-Changle volcanic basin is one of the most promising basalt reservoirs in China for future in-situ carbonation.As for ex-situ carbonation,compared with olivine,diopside or Ca-plagioclase may be more appropriate for increasing ocean negative emissions.
基金CAS Project for Young Scientists in Basic Research(YSBR-037)ANSO collaborative research(ANSO-CR-KP-2022-11)+4 种基金National Natural Science Foundation of China(U2106209,42141003,42141016,and 32171594)Guangdong Basic and Applied Basic Research Foundation(2021B1515020011 and 2021B1212110004)CAS Youth Innovation Promotion Association(2021347)National Forestry and Grassland Administration Youth Talent Support Program(2020BJ003)R&D program of Guangdong Provincial Department of Science and Technology(2018B030324003).
文摘To achieve the Paris Agreement,China pledged to become“Carbon Neutral”by the 2060s.In addition to massive decarbonization,this would require significant changes in ecosystems toward negative CO_(2)emissions.The ability of coastal blue carbon ecosystems(BCEs),including mangrove,salt marsh,and seagrass meadows,to sequester large amounts of CO_(2)makes their conservation and restoration an important“nature-based solution(NbS)”for climate adaptation and mitigation.In this review,we examine how BCEs in China can contribute to climate mitigation.On the national scale,the BCEs in China store up to 118 Tg C across a total area of 1,440,377 ha,including over 75%as unvegetated tidal flats.The annual sedimental C burial of these BCEs reaches up to 2.06 Tg C year^(−1),of which most occurs in salt marshes and tidal flats.The lateral C flux of mangroves and salt marshes contributes to 1.17 Tg C year^(−1)along the Chinese coastline.Conservation and restoration of BCEs benefit climate change mitigation and provide other ecological services with a value of$32,000 ha^(−1)year^(−1).The potential practices and technologies that can be implemented in China to improve BCE C sequestration,including their constraints and feasibility,are also outlined.Future directions are suggested to improve blue carbon estimates on aerial extent,carbon stocks,sequestration,and mitigation potential.Restoring and preserving BCEs would be a cost-effective step to achieve Carbon Neutral by 2060 in China despite various barriers that should be removed.
基金supported by the National Natural Science Foundation of China(nos.U1906216 and 42188102)the National Key Research and Development Program of China(2020YFA0608304)the MOST ONCE project.
文摘Macroalgal mariculture is gaining global attention to achieve carbon neutrality due to its important contribution to ocean carbon sequestration.However,some wild macroalgal species(e.g.,Sargassum and Ulva prolifera)exhibit strong environmental adaptability and can cause large-scale,recurrent blooms in global oceans,fueled by rising atmospheric CO_(2) levels and coastal eutrophication.Notably,massive Ulva prolifera green tides have occurred annually in the Yellow Sea for the past 17 consecutive years.At the late blooming stage,millions of tons of U.prolifera naturally sink to the shallow seafloor.The subsequent intense microbial aerobic degradation of sinking macroalgae results in coastal hypoxia and acidification,with most of the macroalgal carbon returning to the atmosphere.Preventing or reducing the intense degradation of massive sinking U.prolifera could enable more macroalgal carbon storage in the ocean in the long term and alleviate the harmful effects of green tide.Thus,ecological disasters from macroalgal blooms may be transformed into useful natural platforms to increase ocean carbon sequestration.We propose an integrated strategy using environmentally friendly minerals(e.g.,montmorillonite and calcium carbonate)and coagulants(e.g.,polyaluminum chloride),along with natural algicidal bacteria or substances,to induce rapid flocculation and sedimentation of blooming macroalgae,reduce the degradation of sinking macroalgae and its negative environmental impacts,and minimize the generation of macroalgal propagules or seeds and the potential risk for future green tide outbreaks.This integrated approach is potentially a promising approach to tap the carbon sequestration potential of macroalgal blooms to mitigate climate change.
