How coral reefs with high productivity and biodiversity can flourish in oligotrophic tropical oceans has inspired substantial research on coral reef ecosystems.Increasing evidence shows that similar to water in an oas...How coral reefs with high productivity and biodiversity can flourish in oligotrophic tropical oceans has inspired substantial research on coral reef ecosystems.Increasing evidence shows that similar to water in an oasis in the desert,there are stable nutrient supplies to coral reefs in oligotrophic oceans.Here,with emphasis on the fluxes of organic matter,we summarize at the ecosystem level(1)the multiple input pathways of external nutrients,(2)the storage of nutrients in reef organisms,(3)the efficient retaining and recycling of dissolved and particulate organic matter within coral reef ecosystems,(4)the distinctly high phytoplankton productivity and biomass inside and near oceanic coral reefs,and(5)the export of reef-related organic carbon to adjacent open oceans.These properties enable coral reefs to function as ecological“pumps”for gathering nutrients across ecosystems and space,retaining and recycling nutrients within the ecosystem,supporting high phytoplankton productivity,and exporting organic carbon to adjacent open oceans.Particularly,the high phytoplankton productivity and biomass make waters around coral reefs potential hotspots of carbon export to ocean depths via the biological pump.We demonstrate that organic carbon influx is vital for coral reef ecosystems’carbon budget and carbon export.The concept of the coral reef ecological pump provides a framework to improve the understanding of the functioning of the coral reef ecosystem and its responses to disturbance.Prospects of the coral reef ecological pump in coral reef studies are discussed in changing oceans driven by human activities and global change in the Anthropocene.展开更多
The application of human induced oxygen consumption and carbon emission theory in urban region was summed up and on this base a new model of urban carbon and oxygen balance (UCOB) was constructed by calculating the ca...The application of human induced oxygen consumption and carbon emission theory in urban region was summed up and on this base a new model of urban carbon and oxygen balance (UCOB) was constructed by calculating the carbon and oxygen fluxes. The purpose was to highlight the role of vegetation in urban ecosystems and evaluate the effects of various human activities on urban annual oxygen consumption and carbon emission. Hopefully,the model would be helpful in theory to keep the regional balance of carbon and oxygen,and provide guidance and support for urban vegetation planning in the future. To test the UCOB model,the Jimei District of Xiamen City,Fujian Province,China,a very typical urban region,was selected as a case study. The results turn out that Jimei′s vegetation service in oxygen emission and carbon sequestration could not meet the demand of the urban population,and more than 31.49 times of vegetation area should be added to meet the whole oxygen consumption in Jimei while 9.60 times of vegetation area are needed to meet the carbon sequestration targets. The results show that the new UCOB model is of a great potential to be applied to quantitative planning of urban vegetation and regional eco-compensation mechanisms.展开更多
The genus Vibrio,belonging to Gammaproteobacteria of the phylum Proteobacteria,is a genetically and ecologically diverse group of heterotrophic bacteria,that are ubiquitous in marine environments,especially in coastal...The genus Vibrio,belonging to Gammaproteobacteria of the phylum Proteobacteria,is a genetically and ecologically diverse group of heterotrophic bacteria,that are ubiquitous in marine environments,especially in coastal areas.In particular,vibrios dominate,i.e.up to 10%of the readily culturable marine bacteria in these habitats.The distribution of Vibrio spp.is shaped by various environmental parameters,notably temperature,salinity and dissolved organic carbon.Vibriospp.may utilize a wide range of organic carbon compounds,including chitin(this may be metabolized by most Vibrio spp.),alginic acid and agar.Many Vibrio spp.have very short replication times(as short as～10 min),which could facilitate them developing into high biomass content albeit for relatively short durations.Although Vibriospp.usually comprise a minor portion(typically^1%of the total bacterioplankton in coastal waters)of the total microbial population,they have been shown to proliferate explosively in response to various nutrient pulses,e.g.,organic nutrients from algae blooms and iron from Saharan dust.Thus,Vibrio spp.may exert large impacts on marine organic carbon cycling especially in marginal seas.Genomics and related areas of investigation will reveal more about the molecular components and mechanisms involved in Vibrio-mediated biotransformation and remineralization processes.展开更多
To explore the tensile property parameters in the structural design of bridge deck link slabs made by ecological high ductility cementitious composites (Eco-HDCC), the tensile properties of Eco-HDCC exposed to interac...To explore the tensile property parameters in the structural design of bridge deck link slabs made by ecological high ductility cementitious composites (Eco-HDCC), the tensile properties of Eco-HDCC exposed to interactive freeze-thaw-carbonation cycles and single carbonation cycles were studied. The carbonation front of Eco-HDCC was determined by X-ray diffraction and differential scanning calorimetry-thermal gravimetric methods. Results indicate that the carbonation front of Eco-HDCC after interaction tests is deeper than that of Eco-HDCC after single carbonation tests. In addition, the ultimate tensile strength for Eco-HDCC shows an increasing trend after the interaction of 1 to 5 cycles compared with that of virgin specimens, while the ultimate tensile strength decreases after the interaction of 10 to 15 cycles. For single carbonation tests, the ultimate tensile strength of Eco-HDCC increases as cycles increase. After being subjected to interaction and single carbonation environments, both the ultimate tensile strain and tensile strain energy of Eco-HDCC decrease as cycles increase, and the decrease degrees of Eco-HDCC after interaction cycles are larger than those of Eco-HDCC after single carbonation. For general consideration, the tensile stress-strain relationship of Eco-HDCC after the interaction of 15 cycles can be adopted in the design of bridge deck link slabs for the purpose of safety.展开更多
基金The Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou) under contract No.GML2019ZD0405the National Natural Science Foundation of China under contract Nos41506150 and 41130855+3 种基金the Guangdong Basic and Applied Basic Research Foundation under contract No.2019A1515011645the National Science and Technology Basic Work Program of the Ministry of Science and Technology of China under contract No.2015FY110600the Science and Technology Planning Project of Guangdong Province,China under contract No.2020B1212060058the Development Fund of South China Sea Institute of Oceanology of the Chinese Academy of Sciences under contract No.SCSIO202204。
文摘How coral reefs with high productivity and biodiversity can flourish in oligotrophic tropical oceans has inspired substantial research on coral reef ecosystems.Increasing evidence shows that similar to water in an oasis in the desert,there are stable nutrient supplies to coral reefs in oligotrophic oceans.Here,with emphasis on the fluxes of organic matter,we summarize at the ecosystem level(1)the multiple input pathways of external nutrients,(2)the storage of nutrients in reef organisms,(3)the efficient retaining and recycling of dissolved and particulate organic matter within coral reef ecosystems,(4)the distinctly high phytoplankton productivity and biomass inside and near oceanic coral reefs,and(5)the export of reef-related organic carbon to adjacent open oceans.These properties enable coral reefs to function as ecological“pumps”for gathering nutrients across ecosystems and space,retaining and recycling nutrients within the ecosystem,supporting high phytoplankton productivity,and exporting organic carbon to adjacent open oceans.Particularly,the high phytoplankton productivity and biomass make waters around coral reefs potential hotspots of carbon export to ocean depths via the biological pump.We demonstrate that organic carbon influx is vital for coral reef ecosystems’carbon budget and carbon export.The concept of the coral reef ecological pump provides a framework to improve the understanding of the functioning of the coral reef ecosystem and its responses to disturbance.Prospects of the coral reef ecological pump in coral reef studies are discussed in changing oceans driven by human activities and global change in the Anthropocene.
基金Under the auspices of Key Direction in Knowledge Innovation Programs of Chinese Academy of Sciences (No. KZCX2-YW-450, KZCX2-YW-422)
文摘The application of human induced oxygen consumption and carbon emission theory in urban region was summed up and on this base a new model of urban carbon and oxygen balance (UCOB) was constructed by calculating the carbon and oxygen fluxes. The purpose was to highlight the role of vegetation in urban ecosystems and evaluate the effects of various human activities on urban annual oxygen consumption and carbon emission. Hopefully,the model would be helpful in theory to keep the regional balance of carbon and oxygen,and provide guidance and support for urban vegetation planning in the future. To test the UCOB model,the Jimei District of Xiamen City,Fujian Province,China,a very typical urban region,was selected as a case study. The results turn out that Jimei′s vegetation service in oxygen emission and carbon sequestration could not meet the demand of the urban population,and more than 31.49 times of vegetation area should be added to meet the whole oxygen consumption in Jimei while 9.60 times of vegetation area are needed to meet the carbon sequestration targets. The results show that the new UCOB model is of a great potential to be applied to quantitative planning of urban vegetation and regional eco-compensation mechanisms.
基金supported by the National Natural Science Foundation of China (Grant Nos. 41730530, 91751202,41476112)the National Key Research and Development Program of China (Grant No. 2016YFA0601303)
文摘The genus Vibrio,belonging to Gammaproteobacteria of the phylum Proteobacteria,is a genetically and ecologically diverse group of heterotrophic bacteria,that are ubiquitous in marine environments,especially in coastal areas.In particular,vibrios dominate,i.e.up to 10%of the readily culturable marine bacteria in these habitats.The distribution of Vibrio spp.is shaped by various environmental parameters,notably temperature,salinity and dissolved organic carbon.Vibriospp.may utilize a wide range of organic carbon compounds,including chitin(this may be metabolized by most Vibrio spp.),alginic acid and agar.Many Vibrio spp.have very short replication times(as short as～10 min),which could facilitate them developing into high biomass content albeit for relatively short durations.Although Vibriospp.usually comprise a minor portion(typically^1%of the total bacterioplankton in coastal waters)of the total microbial population,they have been shown to proliferate explosively in response to various nutrient pulses,e.g.,organic nutrients from algae blooms and iron from Saharan dust.Thus,Vibrio spp.may exert large impacts on marine organic carbon cycling especially in marginal seas.Genomics and related areas of investigation will reveal more about the molecular components and mechanisms involved in Vibrio-mediated biotransformation and remineralization processes.
基金The National Natural Science Foundation of China(No.51778133)the National Basic Research Program of China(973Program)(No.2015CB655102)+1 种基金the Fundamental Research Funds for the Central Universities(No.3212009403)the China Railway Project(No.2017G007-C)
文摘To explore the tensile property parameters in the structural design of bridge deck link slabs made by ecological high ductility cementitious composites (Eco-HDCC), the tensile properties of Eco-HDCC exposed to interactive freeze-thaw-carbonation cycles and single carbonation cycles were studied. The carbonation front of Eco-HDCC was determined by X-ray diffraction and differential scanning calorimetry-thermal gravimetric methods. Results indicate that the carbonation front of Eco-HDCC after interaction tests is deeper than that of Eco-HDCC after single carbonation tests. In addition, the ultimate tensile strength for Eco-HDCC shows an increasing trend after the interaction of 1 to 5 cycles compared with that of virgin specimens, while the ultimate tensile strength decreases after the interaction of 10 to 15 cycles. For single carbonation tests, the ultimate tensile strength of Eco-HDCC increases as cycles increase. After being subjected to interaction and single carbonation environments, both the ultimate tensile strain and tensile strain energy of Eco-HDCC decrease as cycles increase, and the decrease degrees of Eco-HDCC after interaction cycles are larger than those of Eco-HDCC after single carbonation. For general consideration, the tensile stress-strain relationship of Eco-HDCC after the interaction of 15 cycles can be adopted in the design of bridge deck link slabs for the purpose of safety.
