Because of their effect on climate,carbon dioxide(CO_(2)),methane(CH_(4)),nitrous oxide(N_(2)O),and dimethylsulfide(DMS)are collectively designated as climate-relevant gases(CRGs).CO_(2),CH_(4),and N_(2)O are greenhou...Because of their effect on climate,carbon dioxide(CO_(2)),methane(CH_(4)),nitrous oxide(N_(2)O),and dimethylsulfide(DMS)are collectively designated as climate-relevant gases(CRGs).CO_(2),CH_(4),and N_(2)O are greenhouse gases contributing to global warming(positive climate feedback).Conversely,DMS is involved in the generation of cloud condensation nuclei,thus in the formation of clouds that cool the boundary layer by reflecting incoming solar radiation(negative climate feedback).Despite their scarcity,field observations and model results have demonstrated the essential role of polar oceans in the budget of CRGs.For example,the Southern Ocean represents a substantial CO_(2)sink but a source of N_(2)O and DMS,thereby exerting variable feedback on climate change.Unfortunately,because of the severe environmental conditions at polar latitudes,substantial knowledge gaps remain,for example on the mechanisms underlying CRGs formation or on the strength and distribution of their sources and sinks in the Southern and Arctic Oceans.Here,we review the most recent research results on the distribution,production-loss processes,and abundance variations of CRGs in the polar oceans.We list the remaining knowledge gaps and propose future directions of research on CRGs in the polar oceans,as a useful reference for future studies.展开更多
Mapping potential areas for finfish mariculture,particularly high-yield regions,is crucial for the proper utilization of marine space and global food security.Physiological models(growth performance models)that consid...Mapping potential areas for finfish mariculture,particularly high-yield regions,is crucial for the proper utilization of marine space and global food security.Physiological models(growth performance models)that consider the spatiotemporal heterogeneity of the marine environment are a potentially effective approach to achieving this goal.In the present study,we developed an integrated model that combines the thermal performance curve and spatiotemporal heterogeneity of the marine environment to map the global high-yield potential mariculture areas for 27 commercial finfish species.Our results showed that the current sizes of the potentially suitable areas(achieving 50% of the maximum growth rate for at least six months annually)and high-yield areas(achieving 75% of the maximum growth rate throughout a year)are(8.00±0.30)×10^(6) and(5.96±0.13)×10^(6) km^(2),respectively.Currently,the sizes of suitable and high-yield areas for warm-water mariculture fish are larger than those for other species.The growth potential of suitable mariculture areas is higher at mid and low latitudes than at high latitudes.Under the two shared socioeconomic pathway scenarios(SSP1-2.6 and SSP5-8.5),the sizes of both suitable and high-yield areas will increase by 2050.However,there is the potential for finfish mariculture to respond differently to climate change among species and regions,and cold-water fish may benefit from global warming.Overall,the global potential for suitable high-yield mariculture areas continues to increase,making finfish mariculture an important contributor to global food security.展开更多
Low iron content is a peculiar feature of marine ecosystems,where microbes have to produce iron-chelating molecules such as siderophores to survive.Very little is known about siderophore-producing bacteria in the ocea...Low iron content is a peculiar feature of marine ecosystems,where microbes have to produce iron-chelating molecules such as siderophores to survive.Very little is known about siderophore-producing bacteria in the oceans.In this study,we screened 1546 strains from marine seawater and sediments,which were deposited in the Marine Culture Collection of China(MCCC),and further analyzed the diversity of positive strains and their potential genes related to iron acquisition.Of the 1546 isolates,856 strains(55.37%)showed positive siderophore-producing activity on the Chrome Azurol Sulfonate(CAS)plates.Among these,isolates from seawater environments had a higher positive proportion(535).Some genera showed a higher proportion(>70%)of positive siderophore producers,such as Alteromonas(89/112),Marinobacter(78/109),Vibrio(21/27),Shewanella(7/8)in the Gammaproteobacteria,Sulfitobacter(17/21),Martelella(5/6)in the Alphaproteobacteria,and Joostella(6/7)in the phylum Bacteroidetes.Siderophore biosynthesis genes,including those for vanchrobactin,vibrioferrin,petrobactin,and aerobactin,as well as transport and iron storage proteins,were also identified in the positive bacterial genomes.The study revealed that a variety of bacterial strains demonstrate the production of siderophores,which could significantly contribute to the iron cycle within marine ecosystems,encompassing both seawater and marine sediments.展开更多
The tectonic evolution of Borneo and the affiliation between Southern and Northern Borneo remains unclear.The Rajang and Crocker Fan sediments,as one of the largest ancient submarine fans in Southeast Asia have witnes...The tectonic evolution of Borneo and the affiliation between Southern and Northern Borneo remains unclear.The Rajang and Crocker Fan sediments,as one of the largest ancient submarine fans in Southeast Asia have witnessed the tectonic evolution of Borneo since at least the late Mesozoic.In this study,we present laser ablation inductively coupled plasma mass spectrometer(LA-ICP-MS)U-Pb dating and Hf isotopic results of detrital zircons from the Trusmadi and Crocker formations within the Crocker Fan of Sabah,Northern Borneo.Our results,coupled with previous data,show that the Crocker Fan sediments in Sabah of Northern Borneo display similar age spectra to the Rajang Fan sediments in Sarawak of Central Borneo,with two major age clusters at 130-80 and 280-200 Ma.Further provenance analysis based on mineral shape with a prismatic characteristic and similar detrital zircon Hf isotopes of the two formations illustrates that the Jurassic-Cretaceous and partly Triassic detrital zircons of the Crocker and Rajang Fan sediments were derived from the erosion of contemporaneous magmatic rocks;part of Permian-Triassic ones could be the recycling of the Jurassic deposits in SW Borneo.The initial provenance of these Permian-Triassic detritus could be synchronous magmatic rocks in the Tin belt of the Malay Peninsula.Combining with previous data,we propose that the entire Borneo continent,including both Southern and Northern Borneo,developed a common Mesozoic continental magmatic arc.Moreover,we postulate that the Rajang and Crocker fans formed in a fore-arc extensional rift basin related to the retreat of the subducted Paleo-Pacific Plate beneath the Northern Borneo margin.展开更多
Tissue culture is one of the most promising and practical methods for conserving endangered plant species.Therefore,the present study evaluates the conservation of the endangered seaweed Sargassum fusiforme through ti...Tissue culture is one of the most promising and practical methods for conserving endangered plant species.Therefore,the present study evaluates the conservation of the endangered seaweed Sargassum fusiforme through tissue culturing techniques from different explants for the first time.Besides,the genetic variation of the mother plant and cultivated explants using inter-simple sequence repeat(ISSR)techniques;this methodology was the first to be illustrated in such work for algae tissue culturing.The regeneration results have shown that different explants could induce shoot and rhizoid morphogenesis with a total number of blades of 2436,1011,1466,678,and 6 from apical parts,stipe with blades,two-segmented seedlings,rhizoids,and stipe without blades,respectively.The total length was 234,181.8,83.5,and 81.8 cm from the two-segmented seedlings,apical parts,stipe without blades,and stipe with blades,respectively.At the same time,the total wet weight was 73.148,48.369,35.731,18.588,and 2.035 g from the apical parts,the two-segmented seedlings,stipe with blades,rhizoids,and stipe without blades,respectively.Micropropagation of S.fusiforme was successfully achieved with apical,stipe,and stolon segments using free PES media.It is suggested that the applied genetic fingerprint is valid for S.fusiforme and will respond well to molecular marker assistance in cultivation.The significance of S.fusiforme and its exposure to being endangered due to over-exploitation have made its regeneration in vitro a subject of interest in this study.Thus,this report represents the successful regeneration of S.fusiforme and explores the genetic uniformity or somaclonal variation of the obtained seedlings using the ISSR-PCR marker for the first time.展开更多
Dongshan Bay,along with Xiamen Bay,serves as a significant distribution area for amphioxus in Fujian Province.In this survey,we observed that the sedimentary environment of Dongshan Bay has been seriously silted due t...Dongshan Bay,along with Xiamen Bay,serves as a significant distribution area for amphioxus in Fujian Province.In this survey,we observed that the sedimentary environment of Dongshan Bay has been seriously silted due to rapid economic development and the thriving aquaculture industry.Consequently,there has been a significant reduction in suitable habitats for amphioxus and a sharp decline in its resource abundance.Totally 9 amphioxuses were collected from its eastern region in 2022 with a population density of 18.75 ind m^(-2) and a body length from 34.15 to 48.02 mm.The amphioxuses acquired in this investigation were classified as Branchiostoma japonicum based on morphological traits,such as a cuspate rostral fin,measurements of angles between the dorsal and super-caudal fins,angles between the pre-anal and sub-caudal fins,along with an accurate count of pre-anal fin chambers which matched those observed in B.japonicum.Moreover,a molecular barcoding analysis was conducted using a fragment of the mitochondrial COI gene.The results indicated that Branchiostoma sp.from Dongshan Bay in this study belongs to B.japonicum,providing additional support for the morphological identification results.Considering amphioxuses are still surviving in Dongshan Bay despite the destruction of their habitat,it is recommended to implement measures to safeguard their resources and habitats.The measures may include designating protection areas,strengthening law enforcement management to prohibit sand mining,regulating the scale of cage aquaculture,and augmenting wild resources through artificial breeding and release.展开更多
This study aims to develop and expand a new perspective on ecological value realization(EVR)and provide policy recommendations for marine ecological value realization(MEVR)based on Carbon Trading.Currently,the immatur...This study aims to develop and expand a new perspective on ecological value realization(EVR)and provide policy recommendations for marine ecological value realization(MEVR)based on Carbon Trading.Currently,the immaturity of EVR calculation methods and difficulties in determining the price of ecological products pose significant challenges to ecological value trading.By employing mathematical models and logical reasoning,this study proposes a novel frame-work for EVR,illustrated through several diagrams.According to this frame-work,ecological value is not static but fluctuates with factors such as human well-being(HV)or gross domestic product(GDP).Therefore,ecological value should be determined by an exchange market rather than solely relying on hypothetical calculation methods.Consequently,carbon trading cases are crucial in under-standing ecological value.Based on the analysis of blue carbon(BC)trading cases,including the lack of international BC exchanges,challenges in carbon sink projects,and the Free Rider Effect,this paper identifies current issues in MEVR and BC trading in China.To address these challenges,we propose integrating carbon trading databases with evaluations of ecological protection and restora-tion projects,along with BC trading data,to calculate ecological value.Addi-tionally,we recommend increasing the supply of BC products in both national carbon trading markets and voluntary markets,promoting the internationaliza-tion of BC accounting,addressing the Free Rider Effect through government actions and market mechanisms,attracting more foreign investment in BC en-hancement projects,and formulating a BC enhancement plan during marine resource development.展开更多
The global ocean is a major source of the climate-relevant atmospheric trace gas nitrous oxide(N_(2)O).However,an accurate assessment of the global oceanic emissions of N_(2)O is hampered by missing data on dissolved ...The global ocean is a major source of the climate-relevant atmospheric trace gas nitrous oxide(N_(2)O).However,an accurate assessment of the global oceanic emissions of N_(2)O is hampered by missing data on dissolved N_(2)O from large regions such as the Southern Ocean.To address this deficit,N_(2)O was measured in the Prydz Bay in February 2015 during the 31st Chinese National Antarctic Research Expedition.N_(2)O concentrations(saturation)in the surface layer were generally low(undersaturation with respect to atmospheric equilibrium)and ranged from 13.3 nmol/L to 16.1 nmol/L(83%–102%)at the time of sampling.A comparison of our observations with archived data revealed that no discernible trend in N_(2)O concentrations in the surface waters of Prydz Bay could be detected for the period between 2006 and 2015.Temperature and salinity changes driven by meltwater input were the predominant controls on N_(2)O concentrations in surface waters.At depth,the distribution of N_(2)O concentrations was dominated by production via nitrification in offshore deep waters and vertical convection in the shelf waters,where concentrations were lower and gradients were less steep.Our results suggest a rather unusual pattern of N_(2)O distribution in the Prydz Bay(low N_(2)O in shelf waters compared with the open ocean),providing important insights into the coastal dynamics of N_(2)O in high-latitude polar regions.展开更多
Eutrophic shallow lakes are generally considered as a contributor to the emission of nitrous oxide(N_(2)O),while regional and global estimates have remained imprecise.This due to a lack of data and insufficient unders...Eutrophic shallow lakes are generally considered as a contributor to the emission of nitrous oxide(N_(2)O),while regional and global estimates have remained imprecise.This due to a lack of data and insufficient understanding of the multiple contributing factors.This study characterized the spatiotemporal variability in N_(2)O concentrations and N_(2)O diffusive fluxes and the contributing factors in LakeWuliangsuhai,a typical shallow eutrophic and seasonally frozen lake in Inner Mongolia with cold and arid climate.Dissolved N_(2)O concentrations of the lake exhibited a range of 4.5 to 101.2 nmol/L,displaying significant spatiotemporal variations.The lowest and highest concentrations were measured in summer and winter,respectively.The spatial distribution of N_(2)Ofluxwas consistent with that of N_(2)O concentrations.Additionally,the hotspots of N_(2)O emissions were detected within close to the main inflow of lake.The wide spatial and temporal variation in N_(2)O emissions indicate the complexity and its relative importance of factors influencing emissions.N_(2)O emissions in different lake zones and seasons were regulated by diverse factors.Factors influencing the spatial and temporal distribution of N_(2)O concentrations and fluxes were identified as WT,WD,DO,Chl-a,SD and COD.Interestingly,the same factor demonstrated opposing effects on N_(2)O emission in various seasons or zones.This research improves our understanding of N_(2)O emissions in shallow eutrophic lakes in cold and arid areas.展开更多
Understanding how diet influences the breeding success of Saker Falcons (Falco cherrug) is key to assessing the role of food supply in population dynamics and informing conservation strategies. Through pellet analysis...Understanding how diet influences the breeding success of Saker Falcons (Falco cherrug) is key to assessing the role of food supply in population dynamics and informing conservation strategies. Through pellet analysis, we evaluated the influence of small mammal prey—present in 95% of pellets—on the reproductive performance of the sakers. In Mongolia, three species comprised 95% of the identified small mammals: Mongolian Gerbil (Meriones unguiculatus, 39%), Brandt's Vole (Lasiopodomys brandtii, 49%) and Daurian Pika (Ochotona dauurica, 7%). We found a strong positive association between the proportion of small mammals in the diet and key breeding parameters of sakers. Clutch size, fledged brood sizes, and nest success all increased with a mammal-rich diet. Earlier laying was also linked to higher small mammal intake and was independently associated with improved breeding outcomes. These findings highlight a critical role of small mammal prey in shaping the reproductive success of sakers. Conserving and restoring grassland habitats that support abundant prey populations is essential for sustaining saker populations and achieving long-term conservation goals.展开更多
Mangroves play a pivotal role in tropical and subtropical coastal ecosystem,yet they are highly vulnerable to the effects of climate change,particularly the accelerated global sea level rise(SLR)and stronger tropical ...Mangroves play a pivotal role in tropical and subtropical coastal ecosystem,yet they are highly vulnerable to the effects of climate change,particularly the accelerated global sea level rise(SLR)and stronger tropical cyclones(TCs).However,there is a lack of research addressing future simultaneous combined impacts of the slow-onset of SLR and rapid-onset of TCs on China's mangroves.In order to develop a comprehensive risk assessment method considering the superimposed effects of these two factors and analyze risk for mangroves in Dongzhaigang,Hainan Island,China,we used observational and climate model data to assess the risks to mangroves under low,intermediate,and very high greenhouse gas(GHG)emission scenarios(such as SSP1-2.6,SSP2-4.5,and SSP5-8.5)in 2030,2050,and 2100,and compiled a risk assessment scheme for mangroves in Dongzhaigang,China.The results showed that the combined risks from SLR and TCs will continue to rise;however,SLRs will increase in intensity,and TCs will decrease.The comprehensive risk of the Dongzhaigang mangroves posed by climate change will remain low under SSP1-2.6 and SSP2-4.5 scenarios by 2030,but it will increase substantially by 2100.While under SSP5-8.5 scenario,the risks to mangroves in Dongzhaigang are projected to increase considerably by 2050,and approximately 68.8%of mangroves will be at very high risk by 2100.The risk to the Dongzhaigang mangroves is not only influenced by the hazards but also closely linked to their exposure and vulnerability.We therefore propose climate resilience developmental responses for mangroves to address the effects of climate change.This study for the combined impact of TCs and SLR on mangroves in Dongzhaigang,China can enrich the method system of mangrove risk assessment and provide references for scientific management.展开更多
Petroleum hydrocarbon pollution is a global concern,particularly in coastal environments.Polycyclic aromatic hydrocarbons(PAHs) are regarded as the most toxic components of petroleum hydrocarbons.In this study,the bio...Petroleum hydrocarbon pollution is a global concern,particularly in coastal environments.Polycyclic aromatic hydrocarbons(PAHs) are regarded as the most toxic components of petroleum hydrocarbons.In this study,the biomonitoring and ranking effects of petroleum hydrocarbons and PAHs on the marine fish model Oryzias melastigma embryos were determined in the Jiulong River Estuary(JRE) and its adjacent waters in China.The results showed that the levels of petroleum hydrocarbons from almost all sites met the primary standard for marine seawater quality,and the concentrations of the 16 priority PAHs in the surface seawater were lower compared with those in other coastal areas worldwide.A new fish expert system based on the embryotoxicity of O.melastigma(OME-FES) was developed and applied in the field to evaluate the biological effects of petroleum hydrocarbons and PAHs.The selected physiological index and molecular indicators in OME-FES were appropriate biomarkers for indicating the harmful effects of petroleum hydrocarbons and PAHs.The outcome of OME-FES revealed that the biological effect levels of the sampling sites ranged from level Ⅰ(no stress) to level Ⅲ(medium stress),which is further corroborated by the findings of nested analysis of variance(ANOVA) models.Our results suggest that the OME-FES is an effective tool for evaluating and ranking the biological effects of marine petroleum hydrocarbons and PAHs.This method may also be applied to evaluate other marine pollutants based on its framework.展开更多
The chemical investigation into the EtOAc extract of the deep-sea-derived fungus Penicillium citrinum W22 yielded three unprecedented citrinin dimers,neo-Dicitrinols A–C(1–3)and a known one,penicitrinone A(4).Their ...The chemical investigation into the EtOAc extract of the deep-sea-derived fungus Penicillium citrinum W22 yielded three unprecedented citrinin dimers,neo-Dicitrinols A–C(1–3)and a known one,penicitrinone A(4).Their structures were elucidated by extensive analysis of spectroscopic data,electronic circular dichroism(ECD)calculation,X-ray diffraction,and biogenetic consideration.neo-Dicitrinols A–C(1–3),bearing a tetramic acid unit,represent the first example of citrinin analogues as hybrid polyketide synthase-nonribosomal peptide synthase(PKS-NRPS)products.neo-Dicitrinol C(3)significantly inhibited renin-angiotensin system-selective lethal 3(RSL3)-induced ferroptosis with a half maximal effective concentration(EC50)value of 21.6μmol/L.展开更多
Climate change may threaten the survival of corals due to ocean warming and increased occurrence of extreme weather events.Yet,marginal coral communities demonstrate remarkable adaptability,largely due to stress-toler...Climate change may threaten the survival of corals due to ocean warming and increased occurrence of extreme weather events.Yet,marginal coral communities demonstrate remarkable adaptability,largely due to stress-tolerant species.The mechanisms underlying their resilience to environmental fluctuations remains largely unexplored.Here,we investigated 3 coral species(Cyphastrea serailia,Dipsastraea speciosa,and Duncanopsammia peltata)living at the northern edge of their distribution along the South China coast(Dongshan).Combining physiological and stable isotope analysis,we assessed their traits(symbiont characteristics,C:N ratio,and biomass)and trophic flexibility(i.e.,shifts in isotopic niche or nutritional mode)in response to environmental fluctuations across seasons(autumn,winter,and late spring).Our results revealed distinct physiological traits among these corals,but consistently showed lower symbiont density,higher biomass,and increased chlorophyll content in winter.All corals highly relied on heterotrophy as a crucial adaptive response(consistently no overlap between host and symbiont isotopic niches),but they differed in the degree of trophic plasticity,with D.speciosa showing the highest variability in heterotrophic contribution(36.3%across seasons),followed by C.serailia(21.8%)and D.peltata(8.6%).Notably,the species-specific differences in trophic plasticity well corresponded to the variation in overall isotopic niche and coral distribution.As such,trophic plasticity may play a role in shaping spatial distribution of corals in the marginal community.Overall,this study enhances our understanding of coral resilience in marginal communities and offer new insights into possible mechanisms driving the distribution of reef-building corals in the changing ocean.展开更多
Major differences in beach erosion between two neighboring artificial beaches Xiangluwan Beach(XL beach)and Meiliwan Beach(ML beach)in Zhuhai,China,were studied after Super Typhoon Hato.In this study,a fully nonlinear...Major differences in beach erosion between two neighboring artificial beaches Xiangluwan Beach(XL beach)and Meiliwan Beach(ML beach)in Zhuhai,China,were studied after Super Typhoon Hato.In this study,a fully nonlinear Boussinesq wave model(FUNWAVE)-Total Variation Diminishing(TVD)was used to distinguish the main impact factors,their relative contributions,and the hydrodynamic mechanisms underlying the different beach responses.Results show that compared to the ML beach,the main reason for the relatively weak erosion on Xiangluwan(XL)beach was the smaller beach berm height(accounting for approximately 75.9%of the erosion response).Regarding the beach with a higher berm,the stronger wave-induced undertow flow,along with the higher sediment concentration,led to a higher offshore sediment transport flux,resulting in more severe erosion relative to the beach with a smaller berm height.The second most important reason explaining the weak erosion on XL beach was the absence of seawalls(accounting for approximately 17.9%of the erosion response).Wave reflection induced by the seawall could cause higher suspended sediment concentration,resulting in a toe scouring near the seawall.The offshore submerged breakwater protected XL beach slightly(accounting for approximately 6.1%of the erosion response).Due to the higher water level induced by storm surge,most of the wave energy could penetrate through the submerged breakwater.The effect of the larger berm width of XL beach was negligible.Compared to the beach with a larger berm width,the erosion/deposition regions in the beach with a narrower berm width showed shoreward migration,without significant changes in the erosion/deposition extent.Despite of this,the larger berm width could reduce the wave energy reaching the shoreline.This study of the storm stability of artificial beaches may be applied to beach restoration design.展开更多
The biogeochemical processes of marine sediments are influenced by bioturbation and organic carbon decomposition,which is crucial for understanding global element cycles and climate change.Two sediment cores were acqu...The biogeochemical processes of marine sediments are influenced by bioturbation and organic carbon decomposition,which is crucial for understanding global element cycles and climate change.Two sediment cores were acquired in 2017 from abyssal basins in the central-eastern tropical Pacific to determine the bioturbation and organic carbon degradation processes.The radioactivity concentrations of 210Pb and 226Ra in the sediment cores were measured,indicating the presence of significant excess 210Pb(210Pbex)signals in the sediment cores.Besides,a manganese nodule was discovered in one core,which had a substantial influence on the distribution of 210Pbex.With the exception of this anomalous finding,the bioturbation coefficients in the remaining core were estimated to be 10.6 cm^(2)/a using a steady-state diffusion model,greater than most of the deep-sea sediments from the equatorial eastern Pacific.By using a bio-diffusion model,we further calculated the degradation rates of organic carbon(8.02 ka-1),which is also higher than other areas of the Pacific.Our findings displayed the presence of a biologically active benthic ecosystem in the central-eastern tropical Pacific.展开更多
The genus Marinobacter is very broadly distributed in global environments and is considered as aerobic heterotroph.In this study,six Marinobacter strains were identified with autotrophic thiosulfate oxidation capacity...The genus Marinobacter is very broadly distributed in global environments and is considered as aerobic heterotroph.In this study,six Marinobacter strains were identified with autotrophic thiosulfate oxidation capacity.These strains,namely Marinobacter guineae M3B^(T),Marinobacter aromaticivorans D15-8PT,Marinobacter vulgaris F01^(T),Marinobacter profundi PWS21^(T),Marinobacter denitrificans JB02H27T,and Marinobacter sp.ST-1M(with a 99.93%similarity to the 16S rDNA sequences of Marinobacter salsuginis SD-14B^(T)),were screened out of 32 Marinobacter strains by autotrophic thiosulfate oxidization medium.The population of cells grew in a chemolithotrophic medium,increasing from 105 cells/mL to 10^(7) cells/mL within 5 d.This growth was accompanied by the consumption of thiosulfate 3.59 mmol/L to 9.64 mmol/L and the accumulation of sulfate up to 0.96 mmol/L,and occasionally produced sulfur containing complex particles.Among these Marinobacter strains,it was also found their capability of oxidizing thiosulfate to sulfate in a heterotrophic medium.Notably,M.vulgaris F01^(T)and M.antarcticus ZS2-30^(T)showed highly significant production of sulfate at 9.45 mmol/L and 3.10 mmol/L.Genome annotation indicated that these Marinobacter strains possess a complete Sox cluster for thiosulfate oxidation.Further phylogenetic analysis of the soxB gene revealed that six Marinobacter strains formed a separate lineage within Gammaproteobacteria and close to obligate chemolithoautotroph Thiomicrorhabdus arctica.The results indicated that thiosulfate oxidizing and chemolithoautotrophic potential in Marinobacter genus,which may contribute to the widespread of Marinobacter in the global ocean.展开更多
To better understand the community patterns mediated by connectivity in artificial reefs of coastal areas, it is necessary to understand the distribution and coexistence of organisms with artificial reefs area and adj...To better understand the community patterns mediated by connectivity in artificial reefs of coastal areas, it is necessary to understand the distribution and coexistence of organisms with artificial reefs area and adjacent waters. This study was conducted to examine main catches assemblages collected by trawls in Haizhou Bay,which included five habitats: the artificial reef area(AR), aquaculture area(AA), natural area(NA), estuary area(EA) and comprehensive effect area(CEA). The result shows that the total abundances of species in the five habitats were highly different(univariate PERMANOVA: P = 0.001, n = 24), but some species were also unique in their habitat(e.g. Scapharca subcrenata and Glossaulax didyma in AA). The body size distribution of specific species between habitats are different. For Collichthys lucidus, their body size in AR(14.63 cm ± 1.64 cm) and EA(14.3 cm ± 0.85 cm) is higher than that in NA(10.65 cm ± 1.64 cm), CEA(11.28 cm ± 1.85 cm) and AA(12.1 cm ±0.43 cm), which indicates the potential connection from AR to EA mediated by their adult population. We concluded that artificial reefs in AR can be considered key components that have the ability to support species assemblages in adjacent habitats. This study has implications for the conservation and monitoring of species assemblages in coastal areas in terms of that artificial reefs can be applied in different stages of habitat protection implementation and in different combinations of scenarios.展开更多
By establishing a distribution and environmental factor database of 21 typical harmful dinoflagellates in global waters,the MaxEnt model was used to predict shifts in the habitat of harmful dinoflagellates in Chinese ...By establishing a distribution and environmental factor database of 21 typical harmful dinoflagellates in global waters,the MaxEnt model was used to predict shifts in the habitat of harmful dinoflagellates in Chinese waters under global climate change.The results revealed that offshore distance was the most important predictive factor and that surface seawater temperature(SST),primary productivity,and nitrate concentration were the key ecological factors influencing the distribution of harmful dinoflagellates.Under the low greenhouse gas emission scenario defined by the Intergovernmental Panel on Climate Change(IPCC),by approximately 2050,17 of the 21harmful dinoflagellate species in high-suitability areas(HSA)will migrate northward,six species will migrate eastward,and six species will expand their HSA.By 2100,approximately 18 of the 21 harmful dinoflagellate species in HSA will have migrated northward,seven species will have migrated eastward,and four species will have expanded their HSA.Notably,the HSA content of highly toxic Alexandrium minutum is expected to increase by 13.4%and 9.4%by 2050 and 2100,respectively.Under the high greenhouse gas emissions,there will be 17species migrating northward,6 species migrating eastward,and 4 species increasing in their size in HSA by 2050;moreover,there will be 16 species migrating northward,2 migrating eastward,and 4 species according to their size of HSA by 2100.Specifically,the HSA of A.minutum is predicted to increase by 7.0%and 25.9%by 2050 and 2100,respectively.Notably,A.ostenfeldii,which is currently seldom present in the China seas,is predicted to exhibit an HSA in most coastal areas of the Yellow Sea,the Bohai Sea,the Hangzhou Bay,the Zhejiang Coast,and the Beibu Gulf of the South China Sea.Conversely,the HSA of Noctiluca scintillans,a typical red-tide species,will be reduced by 7%–90%.The northward migration of Karenia mikimotoi exceeded 100 km and 300 km under low and high greenhouse gas emission scenarios,respectively.These changes underscore the significant impact of climate change on the distribution and habitat suitability of harmful dinoflagellates,thus indicating a potential shift in their ecological dynamics and consequent effects on marine ecosystems.展开更多
Global carbon cycle has received extensive attention,among which the river-estuary system is one of the important links connecting the carbon cycle between land and ocean.In this paper,the distribution and control fac...Global carbon cycle has received extensive attention,among which the river-estuary system is one of the important links connecting the carbon cycle between land and ocean.In this paper,the distribution and control factors of particulate organic carbon(POC)were studied by using the data of organic carbon contents and its carbon isotopic composition(δ13C)in the mainstream and estuary of Passur River in the Sundarbans area,combined with the hydrological and biological data measured by CTD.The results show that POC content ranged from 0.263 mg/L to 9.292 mg/L,and the POC content in the river section(averaged 4.129 mg/L)was significantly higher than that in the estuary area(averaged 0.858 mg/L).Two distinct stages of POC transport from land to sea in the Sundarbans area were identified.The first stage occurred in the river section,where POC distribution was mainly controlled by the dynamic process of runoff and the organic carbon was mainly terrestrial source.The second stage occurred during estuarine mixing,where the POC distribution was mainly controlled by the mixing process of seawater and freshwater.The source of POC was predominantly marine and exhibiting vertical differences.The surface and middle layers were primarily influenced by marine sources,while the bottom layer was jointly controlled by terrestrial and marine sources of organic carbon.These findings are of great significance for understanding the carbon cycle in such a large mangrove ecosystem like the Sundarbans mangrove.展开更多
基金supported the National Natural Science Foundation of China(Grant nos.4227624,42376239 and 42476253)。
文摘Because of their effect on climate,carbon dioxide(CO_(2)),methane(CH_(4)),nitrous oxide(N_(2)O),and dimethylsulfide(DMS)are collectively designated as climate-relevant gases(CRGs).CO_(2),CH_(4),and N_(2)O are greenhouse gases contributing to global warming(positive climate feedback).Conversely,DMS is involved in the generation of cloud condensation nuclei,thus in the formation of clouds that cool the boundary layer by reflecting incoming solar radiation(negative climate feedback).Despite their scarcity,field observations and model results have demonstrated the essential role of polar oceans in the budget of CRGs.For example,the Southern Ocean represents a substantial CO_(2)sink but a source of N_(2)O and DMS,thereby exerting variable feedback on climate change.Unfortunately,because of the severe environmental conditions at polar latitudes,substantial knowledge gaps remain,for example on the mechanisms underlying CRGs formation or on the strength and distribution of their sources and sinks in the Southern and Arctic Oceans.Here,we review the most recent research results on the distribution,production-loss processes,and abundance variations of CRGs in the polar oceans.We list the remaining knowledge gaps and propose future directions of research on CRGs in the polar oceans,as a useful reference for future studies.
基金supported by the National Natural Science Founda-tion of China(42025604)the Fundamental Research Funds for the Central Universities of the Ocean University of China.
文摘Mapping potential areas for finfish mariculture,particularly high-yield regions,is crucial for the proper utilization of marine space and global food security.Physiological models(growth performance models)that consider the spatiotemporal heterogeneity of the marine environment are a potentially effective approach to achieving this goal.In the present study,we developed an integrated model that combines the thermal performance curve and spatiotemporal heterogeneity of the marine environment to map the global high-yield potential mariculture areas for 27 commercial finfish species.Our results showed that the current sizes of the potentially suitable areas(achieving 50% of the maximum growth rate for at least six months annually)and high-yield areas(achieving 75% of the maximum growth rate throughout a year)are(8.00±0.30)×10^(6) and(5.96±0.13)×10^(6) km^(2),respectively.Currently,the sizes of suitable and high-yield areas for warm-water mariculture fish are larger than those for other species.The growth potential of suitable mariculture areas is higher at mid and low latitudes than at high latitudes.Under the two shared socioeconomic pathway scenarios(SSP1-2.6 and SSP5-8.5),the sizes of both suitable and high-yield areas will increase by 2050.However,there is the potential for finfish mariculture to respond differently to climate change among species and regions,and cold-water fish may benefit from global warming.Overall,the global potential for suitable high-yield mariculture areas continues to increase,making finfish mariculture an important contributor to global food security.
基金The National Key Research and Development Program of China under contact No.2021YFF0501304the Natural Science Foundation of Xiamen,China under contact No.3502Z20227244the Scientific Research Foundation of the Third Institute of Oceanography,MNR under contact Nos 2019021 and 2022009.
文摘Low iron content is a peculiar feature of marine ecosystems,where microbes have to produce iron-chelating molecules such as siderophores to survive.Very little is known about siderophore-producing bacteria in the oceans.In this study,we screened 1546 strains from marine seawater and sediments,which were deposited in the Marine Culture Collection of China(MCCC),and further analyzed the diversity of positive strains and their potential genes related to iron acquisition.Of the 1546 isolates,856 strains(55.37%)showed positive siderophore-producing activity on the Chrome Azurol Sulfonate(CAS)plates.Among these,isolates from seawater environments had a higher positive proportion(535).Some genera showed a higher proportion(>70%)of positive siderophore producers,such as Alteromonas(89/112),Marinobacter(78/109),Vibrio(21/27),Shewanella(7/8)in the Gammaproteobacteria,Sulfitobacter(17/21),Martelella(5/6)in the Alphaproteobacteria,and Joostella(6/7)in the phylum Bacteroidetes.Siderophore biosynthesis genes,including those for vanchrobactin,vibrioferrin,petrobactin,and aerobactin,as well as transport and iron storage proteins,were also identified in the positive bacterial genomes.The study revealed that a variety of bacterial strains demonstrate the production of siderophores,which could significantly contribute to the iron cycle within marine ecosystems,encompassing both seawater and marine sediments.
基金jointly supported by the Scientific Research Foundation of Third Institute of Oceanography,Ministry of Natural Resources,Xiamen(No.2018002)the Guangxi Natural Science Fundation(No.2022GXNSFBA035588)+1 种基金the National Natural Science Foundation of China(Nos.41506050,41402193)the Scientific Research Foundation of Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration(No.19-185-17-09)。
文摘The tectonic evolution of Borneo and the affiliation between Southern and Northern Borneo remains unclear.The Rajang and Crocker Fan sediments,as one of the largest ancient submarine fans in Southeast Asia have witnessed the tectonic evolution of Borneo since at least the late Mesozoic.In this study,we present laser ablation inductively coupled plasma mass spectrometer(LA-ICP-MS)U-Pb dating and Hf isotopic results of detrital zircons from the Trusmadi and Crocker formations within the Crocker Fan of Sabah,Northern Borneo.Our results,coupled with previous data,show that the Crocker Fan sediments in Sabah of Northern Borneo display similar age spectra to the Rajang Fan sediments in Sarawak of Central Borneo,with two major age clusters at 130-80 and 280-200 Ma.Further provenance analysis based on mineral shape with a prismatic characteristic and similar detrital zircon Hf isotopes of the two formations illustrates that the Jurassic-Cretaceous and partly Triassic detrital zircons of the Crocker and Rajang Fan sediments were derived from the erosion of contemporaneous magmatic rocks;part of Permian-Triassic ones could be the recycling of the Jurassic deposits in SW Borneo.The initial provenance of these Permian-Triassic detritus could be synchronous magmatic rocks in the Tin belt of the Malay Peninsula.Combining with previous data,we propose that the entire Borneo continent,including both Southern and Northern Borneo,developed a common Mesozoic continental magmatic arc.Moreover,we postulate that the Rajang and Crocker fans formed in a fore-arc extensional rift basin related to the retreat of the subducted Paleo-Pacific Plate beneath the Northern Borneo margin.
基金supported by the grants from China Asia-Pacific Economic Cooperation(Nos.HV180101 and HV01-190101)the Xiamen Science and Technology Program(No.3502Z20161162)the Specific Fund Project of Xiamen Marine and Fishery Development(No.19CZP011HJ08).
文摘Tissue culture is one of the most promising and practical methods for conserving endangered plant species.Therefore,the present study evaluates the conservation of the endangered seaweed Sargassum fusiforme through tissue culturing techniques from different explants for the first time.Besides,the genetic variation of the mother plant and cultivated explants using inter-simple sequence repeat(ISSR)techniques;this methodology was the first to be illustrated in such work for algae tissue culturing.The regeneration results have shown that different explants could induce shoot and rhizoid morphogenesis with a total number of blades of 2436,1011,1466,678,and 6 from apical parts,stipe with blades,two-segmented seedlings,rhizoids,and stipe without blades,respectively.The total length was 234,181.8,83.5,and 81.8 cm from the two-segmented seedlings,apical parts,stipe without blades,and stipe with blades,respectively.At the same time,the total wet weight was 73.148,48.369,35.731,18.588,and 2.035 g from the apical parts,the two-segmented seedlings,stipe with blades,rhizoids,and stipe without blades,respectively.Micropropagation of S.fusiforme was successfully achieved with apical,stipe,and stolon segments using free PES media.It is suggested that the applied genetic fingerprint is valid for S.fusiforme and will respond well to molecular marker assistance in cultivation.The significance of S.fusiforme and its exposure to being endangered due to over-exploitation have made its regeneration in vitro a subject of interest in this study.Thus,this report represents the successful regeneration of S.fusiforme and explores the genetic uniformity or somaclonal variation of the obtained seedlings using the ISSR-PCR marker for the first time.
基金supported by grants from the Science and Technology Bureau of Xiamen(No.3502Z20227207)。
文摘Dongshan Bay,along with Xiamen Bay,serves as a significant distribution area for amphioxus in Fujian Province.In this survey,we observed that the sedimentary environment of Dongshan Bay has been seriously silted due to rapid economic development and the thriving aquaculture industry.Consequently,there has been a significant reduction in suitable habitats for amphioxus and a sharp decline in its resource abundance.Totally 9 amphioxuses were collected from its eastern region in 2022 with a population density of 18.75 ind m^(-2) and a body length from 34.15 to 48.02 mm.The amphioxuses acquired in this investigation were classified as Branchiostoma japonicum based on morphological traits,such as a cuspate rostral fin,measurements of angles between the dorsal and super-caudal fins,angles between the pre-anal and sub-caudal fins,along with an accurate count of pre-anal fin chambers which matched those observed in B.japonicum.Moreover,a molecular barcoding analysis was conducted using a fragment of the mitochondrial COI gene.The results indicated that Branchiostoma sp.from Dongshan Bay in this study belongs to B.japonicum,providing additional support for the morphological identification results.Considering amphioxuses are still surviving in Dongshan Bay despite the destruction of their habitat,it is recommended to implement measures to safeguard their resources and habitats.The measures may include designating protection areas,strengthening law enforcement management to prohibit sand mining,regulating the scale of cage aquaculture,and augmenting wild resources through artificial breeding and release.
基金Fund of Laboratory of Marine Ecological Conservation and Restoration,Ministry of Natural Resources/Fujian Provincial Key Laboratory of Marine Ecological Conservation and Restoration,Grant/Award Number:EPR2023010Fund of Key Laboratory of Marine Environmental Survey Technology and Application,Ministry of Natural Resources,Grant/Award Number:MESTA-2022-D003。
文摘This study aims to develop and expand a new perspective on ecological value realization(EVR)and provide policy recommendations for marine ecological value realization(MEVR)based on Carbon Trading.Currently,the immaturity of EVR calculation methods and difficulties in determining the price of ecological products pose significant challenges to ecological value trading.By employing mathematical models and logical reasoning,this study proposes a novel frame-work for EVR,illustrated through several diagrams.According to this frame-work,ecological value is not static but fluctuates with factors such as human well-being(HV)or gross domestic product(GDP).Therefore,ecological value should be determined by an exchange market rather than solely relying on hypothetical calculation methods.Consequently,carbon trading cases are crucial in under-standing ecological value.Based on the analysis of blue carbon(BC)trading cases,including the lack of international BC exchanges,challenges in carbon sink projects,and the Free Rider Effect,this paper identifies current issues in MEVR and BC trading in China.To address these challenges,we propose integrating carbon trading databases with evaluations of ecological protection and restora-tion projects,along with BC trading data,to calculate ecological value.Addi-tionally,we recommend increasing the supply of BC products in both national carbon trading markets and voluntary markets,promoting the internationaliza-tion of BC accounting,addressing the Free Rider Effect through government actions and market mechanisms,attracting more foreign investment in BC en-hancement projects,and formulating a BC enhancement plan during marine resource development.
基金The National Natural Science Foundation of China under contract No.41906193the Scientific Research Foundation of Third Institute of Oceanography,Ministry of Natural Resources,under contract No.2019033+2 种基金the Natural Science Foundation of Fujian Province under contract No.2019J05147the Federal Ministry of Education and Research of Germany under contract No.FKZ 03F03F0783Athe National Polar Special Program under contract Nos IRASCC 01-01-02 and IRASCC 02-02.
文摘The global ocean is a major source of the climate-relevant atmospheric trace gas nitrous oxide(N_(2)O).However,an accurate assessment of the global oceanic emissions of N_(2)O is hampered by missing data on dissolved N_(2)O from large regions such as the Southern Ocean.To address this deficit,N_(2)O was measured in the Prydz Bay in February 2015 during the 31st Chinese National Antarctic Research Expedition.N_(2)O concentrations(saturation)in the surface layer were generally low(undersaturation with respect to atmospheric equilibrium)and ranged from 13.3 nmol/L to 16.1 nmol/L(83%–102%)at the time of sampling.A comparison of our observations with archived data revealed that no discernible trend in N_(2)O concentrations in the surface waters of Prydz Bay could be detected for the period between 2006 and 2015.Temperature and salinity changes driven by meltwater input were the predominant controls on N_(2)O concentrations in surface waters.At depth,the distribution of N_(2)O concentrations was dominated by production via nitrification in offshore deep waters and vertical convection in the shelf waters,where concentrations were lower and gradients were less steep.Our results suggest a rather unusual pattern of N_(2)O distribution in the Prydz Bay(low N_(2)O in shelf waters compared with the open ocean),providing important insights into the coastal dynamics of N_(2)O in high-latitude polar regions.
基金supported by the National Natural Science Foundation of China(Nos.52260028,52060022,52260029,and 52160021)the National Key Research and Development Program of China(Nos.2017YFE0114800 and 2019YFC0409200)+1 种基金Inner Mongolia Autonomous Region Science and Technology Plan(No.2021GG0089)personal grant to Guohua Li by China Scholarship Council(CSC).
文摘Eutrophic shallow lakes are generally considered as a contributor to the emission of nitrous oxide(N_(2)O),while regional and global estimates have remained imprecise.This due to a lack of data and insufficient understanding of the multiple contributing factors.This study characterized the spatiotemporal variability in N_(2)O concentrations and N_(2)O diffusive fluxes and the contributing factors in LakeWuliangsuhai,a typical shallow eutrophic and seasonally frozen lake in Inner Mongolia with cold and arid climate.Dissolved N_(2)O concentrations of the lake exhibited a range of 4.5 to 101.2 nmol/L,displaying significant spatiotemporal variations.The lowest and highest concentrations were measured in summer and winter,respectively.The spatial distribution of N_(2)Ofluxwas consistent with that of N_(2)O concentrations.Additionally,the hotspots of N_(2)O emissions were detected within close to the main inflow of lake.The wide spatial and temporal variation in N_(2)O emissions indicate the complexity and its relative importance of factors influencing emissions.N_(2)O emissions in different lake zones and seasons were regulated by diverse factors.Factors influencing the spatial and temporal distribution of N_(2)O concentrations and fluxes were identified as WT,WD,DO,Chl-a,SD and COD.Interestingly,the same factor demonstrated opposing effects on N_(2)O emission in various seasons or zones.This research improves our understanding of N_(2)O emissions in shallow eutrophic lakes in cold and arid areas.
基金supported by the National Natural Science Foundation of China (32125005, 32361133559)the Institute of Zoology,Chinese Academy of Sciences (2023IOZ0104)+2 种基金the Third Xinjiang Scientific Expedition Program (Grant No. 2022xjkk0800)the CAS-TWAS President’s Fellowship programme (BB)The Environment Agency Abu Dhabi (EAD) funded the project under a MOU with Mongolia’s Ministry of Environment and Green Development (MEGD)
文摘Understanding how diet influences the breeding success of Saker Falcons (Falco cherrug) is key to assessing the role of food supply in population dynamics and informing conservation strategies. Through pellet analysis, we evaluated the influence of small mammal prey—present in 95% of pellets—on the reproductive performance of the sakers. In Mongolia, three species comprised 95% of the identified small mammals: Mongolian Gerbil (Meriones unguiculatus, 39%), Brandt's Vole (Lasiopodomys brandtii, 49%) and Daurian Pika (Ochotona dauurica, 7%). We found a strong positive association between the proportion of small mammals in the diet and key breeding parameters of sakers. Clutch size, fledged brood sizes, and nest success all increased with a mammal-rich diet. Earlier laying was also linked to higher small mammal intake and was independently associated with improved breeding outcomes. These findings highlight a critical role of small mammal prey in shaping the reproductive success of sakers. Conserving and restoring grassland habitats that support abundant prey populations is essential for sustaining saker populations and achieving long-term conservation goals.
基金Under the auspices of the National Key Research and Development Program of China (No.2017YFA0604902,2017YFA0604903,2017YFA0604901)。
文摘Mangroves play a pivotal role in tropical and subtropical coastal ecosystem,yet they are highly vulnerable to the effects of climate change,particularly the accelerated global sea level rise(SLR)and stronger tropical cyclones(TCs).However,there is a lack of research addressing future simultaneous combined impacts of the slow-onset of SLR and rapid-onset of TCs on China's mangroves.In order to develop a comprehensive risk assessment method considering the superimposed effects of these two factors and analyze risk for mangroves in Dongzhaigang,Hainan Island,China,we used observational and climate model data to assess the risks to mangroves under low,intermediate,and very high greenhouse gas(GHG)emission scenarios(such as SSP1-2.6,SSP2-4.5,and SSP5-8.5)in 2030,2050,and 2100,and compiled a risk assessment scheme for mangroves in Dongzhaigang,China.The results showed that the combined risks from SLR and TCs will continue to rise;however,SLRs will increase in intensity,and TCs will decrease.The comprehensive risk of the Dongzhaigang mangroves posed by climate change will remain low under SSP1-2.6 and SSP2-4.5 scenarios by 2030,but it will increase substantially by 2100.While under SSP5-8.5 scenario,the risks to mangroves in Dongzhaigang are projected to increase considerably by 2050,and approximately 68.8%of mangroves will be at very high risk by 2100.The risk to the Dongzhaigang mangroves is not only influenced by the hazards but also closely linked to their exposure and vulnerability.We therefore propose climate resilience developmental responses for mangroves to address the effects of climate change.This study for the combined impact of TCs and SLR on mangroves in Dongzhaigang,China can enrich the method system of mangrove risk assessment and provide references for scientific management.
基金The Scientific Research Foundation of the Third Institute of Oceanography,Ministry of Natural Resources under contract Nos 2020014 and 2020017the National Natural Science Foundation of China under contract No.41977211the National Program on Global Change and Air-Sea Interaction under contract No.GASI-02-SCS-YDsum。
文摘Petroleum hydrocarbon pollution is a global concern,particularly in coastal environments.Polycyclic aromatic hydrocarbons(PAHs) are regarded as the most toxic components of petroleum hydrocarbons.In this study,the biomonitoring and ranking effects of petroleum hydrocarbons and PAHs on the marine fish model Oryzias melastigma embryos were determined in the Jiulong River Estuary(JRE) and its adjacent waters in China.The results showed that the levels of petroleum hydrocarbons from almost all sites met the primary standard for marine seawater quality,and the concentrations of the 16 priority PAHs in the surface seawater were lower compared with those in other coastal areas worldwide.A new fish expert system based on the embryotoxicity of O.melastigma(OME-FES) was developed and applied in the field to evaluate the biological effects of petroleum hydrocarbons and PAHs.The selected physiological index and molecular indicators in OME-FES were appropriate biomarkers for indicating the harmful effects of petroleum hydrocarbons and PAHs.The outcome of OME-FES revealed that the biological effect levels of the sampling sites ranged from level Ⅰ(no stress) to level Ⅲ(medium stress),which is further corroborated by the findings of nested analysis of variance(ANOVA) models.Our results suggest that the OME-FES is an effective tool for evaluating and ranking the biological effects of marine petroleum hydrocarbons and PAHs.This method may also be applied to evaluate other marine pollutants based on its framework.
基金financially supported by the Xiamen Southern Oceanographic Center(No.22GYY007HJ07)。
文摘The chemical investigation into the EtOAc extract of the deep-sea-derived fungus Penicillium citrinum W22 yielded three unprecedented citrinin dimers,neo-Dicitrinols A–C(1–3)and a known one,penicitrinone A(4).Their structures were elucidated by extensive analysis of spectroscopic data,electronic circular dichroism(ECD)calculation,X-ray diffraction,and biogenetic consideration.neo-Dicitrinols A–C(1–3),bearing a tetramic acid unit,represent the first example of citrinin analogues as hybrid polyketide synthase-nonribosomal peptide synthase(PKS-NRPS)products.neo-Dicitrinol C(3)significantly inhibited renin-angiotensin system-selective lethal 3(RSL3)-induced ferroptosis with a half maximal effective concentration(EC50)value of 21.6μmol/L.
基金supported by the National Key Research and Development Program of China(2022YFF0802202)the Scientific Research Foundation of the Third Institute of Oceanography,Ministry of Natural Resources of China(no.2019017)+2 种基金the Shenzhen Science and Technology Program(grant number KCXFZ20211020165547011)the National Natural Science Foundation of China(no.42376110,41976127)the Fujian Provincial Natural Science Funds for Distinguished Young Scholar(2023J06043)
文摘Climate change may threaten the survival of corals due to ocean warming and increased occurrence of extreme weather events.Yet,marginal coral communities demonstrate remarkable adaptability,largely due to stress-tolerant species.The mechanisms underlying their resilience to environmental fluctuations remains largely unexplored.Here,we investigated 3 coral species(Cyphastrea serailia,Dipsastraea speciosa,and Duncanopsammia peltata)living at the northern edge of their distribution along the South China coast(Dongshan).Combining physiological and stable isotope analysis,we assessed their traits(symbiont characteristics,C:N ratio,and biomass)and trophic flexibility(i.e.,shifts in isotopic niche or nutritional mode)in response to environmental fluctuations across seasons(autumn,winter,and late spring).Our results revealed distinct physiological traits among these corals,but consistently showed lower symbiont density,higher biomass,and increased chlorophyll content in winter.All corals highly relied on heterotrophy as a crucial adaptive response(consistently no overlap between host and symbiont isotopic niches),but they differed in the degree of trophic plasticity,with D.speciosa showing the highest variability in heterotrophic contribution(36.3%across seasons),followed by C.serailia(21.8%)and D.peltata(8.6%).Notably,the species-specific differences in trophic plasticity well corresponded to the variation in overall isotopic niche and coral distribution.As such,trophic plasticity may play a role in shaping spatial distribution of corals in the marginal community.Overall,this study enhances our understanding of coral resilience in marginal communities and offer new insights into possible mechanisms driving the distribution of reef-building corals in the changing ocean.
基金Supported by the National Natural Science Foundation of China(Nos.42006176,42330406,U1706220,41901006)the Basic Research Project of the Science and Technology Innovation Development Program of in Yantai(No.2022JCYJ028)。
文摘Major differences in beach erosion between two neighboring artificial beaches Xiangluwan Beach(XL beach)and Meiliwan Beach(ML beach)in Zhuhai,China,were studied after Super Typhoon Hato.In this study,a fully nonlinear Boussinesq wave model(FUNWAVE)-Total Variation Diminishing(TVD)was used to distinguish the main impact factors,their relative contributions,and the hydrodynamic mechanisms underlying the different beach responses.Results show that compared to the ML beach,the main reason for the relatively weak erosion on Xiangluwan(XL)beach was the smaller beach berm height(accounting for approximately 75.9%of the erosion response).Regarding the beach with a higher berm,the stronger wave-induced undertow flow,along with the higher sediment concentration,led to a higher offshore sediment transport flux,resulting in more severe erosion relative to the beach with a smaller berm height.The second most important reason explaining the weak erosion on XL beach was the absence of seawalls(accounting for approximately 17.9%of the erosion response).Wave reflection induced by the seawall could cause higher suspended sediment concentration,resulting in a toe scouring near the seawall.The offshore submerged breakwater protected XL beach slightly(accounting for approximately 6.1%of the erosion response).Due to the higher water level induced by storm surge,most of the wave energy could penetrate through the submerged breakwater.The effect of the larger berm width of XL beach was negligible.Compared to the beach with a larger berm width,the erosion/deposition regions in the beach with a narrower berm width showed shoreward migration,without significant changes in the erosion/deposition extent.Despite of this,the larger berm width could reduce the wave energy reaching the shoreline.This study of the storm stability of artificial beaches may be applied to beach restoration design.
基金The Scientific Research Foundation of Third Institute of Oceanography,Ministry of Natural Resources under contract No.2020012the Natural Science Foundation of Xiamen,China under contract No.3502Z20227246the Guiding Project of the Science and Technology Plan of Fujian Province under contract No.2020Y0081.
文摘The biogeochemical processes of marine sediments are influenced by bioturbation and organic carbon decomposition,which is crucial for understanding global element cycles and climate change.Two sediment cores were acquired in 2017 from abyssal basins in the central-eastern tropical Pacific to determine the bioturbation and organic carbon degradation processes.The radioactivity concentrations of 210Pb and 226Ra in the sediment cores were measured,indicating the presence of significant excess 210Pb(210Pbex)signals in the sediment cores.Besides,a manganese nodule was discovered in one core,which had a substantial influence on the distribution of 210Pbex.With the exception of this anomalous finding,the bioturbation coefficients in the remaining core were estimated to be 10.6 cm^(2)/a using a steady-state diffusion model,greater than most of the deep-sea sediments from the equatorial eastern Pacific.By using a bio-diffusion model,we further calculated the degradation rates of organic carbon(8.02 ka-1),which is also higher than other areas of the Pacific.Our findings displayed the presence of a biologically active benthic ecosystem in the central-eastern tropical Pacific.
基金The National Natural Science Foundation of China under contract Nos 91951201 and 42030412the National Key R&D Program of China under contract No.2021YFF0501304the Scientific Research Foundation of Third Institute of Oceanography,MNR under contract No.2019021.
文摘The genus Marinobacter is very broadly distributed in global environments and is considered as aerobic heterotroph.In this study,six Marinobacter strains were identified with autotrophic thiosulfate oxidation capacity.These strains,namely Marinobacter guineae M3B^(T),Marinobacter aromaticivorans D15-8PT,Marinobacter vulgaris F01^(T),Marinobacter profundi PWS21^(T),Marinobacter denitrificans JB02H27T,and Marinobacter sp.ST-1M(with a 99.93%similarity to the 16S rDNA sequences of Marinobacter salsuginis SD-14B^(T)),were screened out of 32 Marinobacter strains by autotrophic thiosulfate oxidization medium.The population of cells grew in a chemolithotrophic medium,increasing from 105 cells/mL to 10^(7) cells/mL within 5 d.This growth was accompanied by the consumption of thiosulfate 3.59 mmol/L to 9.64 mmol/L and the accumulation of sulfate up to 0.96 mmol/L,and occasionally produced sulfur containing complex particles.Among these Marinobacter strains,it was also found their capability of oxidizing thiosulfate to sulfate in a heterotrophic medium.Notably,M.vulgaris F01^(T)and M.antarcticus ZS2-30^(T)showed highly significant production of sulfate at 9.45 mmol/L and 3.10 mmol/L.Genome annotation indicated that these Marinobacter strains possess a complete Sox cluster for thiosulfate oxidation.Further phylogenetic analysis of the soxB gene revealed that six Marinobacter strains formed a separate lineage within Gammaproteobacteria and close to obligate chemolithoautotroph Thiomicrorhabdus arctica.The results indicated that thiosulfate oxidizing and chemolithoautotrophic potential in Marinobacter genus,which may contribute to the widespread of Marinobacter in the global ocean.
基金The China Scholarship Council under contract No.202308310175the China Postdoctoral Science Foundation under contract No.E-6005-00-0042-39+6 种基金Postdoctoral Fellowship Program of CPSF under contract No. GZC20231539the Jiangsu Haizhou Bay National Sea Ranching Demonstration Project under contract No. D–8005–18–0188Shanghai Municipal Science and Technology Commission Local Capacity Construction Project under contract No. 21010502200the Science Foundation for Youths of Jiangsu ProvinceChina under contract No. BK20170438the Science and Technology Projects in Nantong under contract No. JC2018014the Social Livelihood Key Projects of Nantong under contract No. MS22021015。
文摘To better understand the community patterns mediated by connectivity in artificial reefs of coastal areas, it is necessary to understand the distribution and coexistence of organisms with artificial reefs area and adjacent waters. This study was conducted to examine main catches assemblages collected by trawls in Haizhou Bay,which included five habitats: the artificial reef area(AR), aquaculture area(AA), natural area(NA), estuary area(EA) and comprehensive effect area(CEA). The result shows that the total abundances of species in the five habitats were highly different(univariate PERMANOVA: P = 0.001, n = 24), but some species were also unique in their habitat(e.g. Scapharca subcrenata and Glossaulax didyma in AA). The body size distribution of specific species between habitats are different. For Collichthys lucidus, their body size in AR(14.63 cm ± 1.64 cm) and EA(14.3 cm ± 0.85 cm) is higher than that in NA(10.65 cm ± 1.64 cm), CEA(11.28 cm ± 1.85 cm) and AA(12.1 cm ±0.43 cm), which indicates the potential connection from AR to EA mediated by their adult population. We concluded that artificial reefs in AR can be considered key components that have the ability to support species assemblages in adjacent habitats. This study has implications for the conservation and monitoring of species assemblages in coastal areas in terms of that artificial reefs can be applied in different stages of habitat protection implementation and in different combinations of scenarios.
基金The National Key Research and Development Program of China under contract Nos 2019YFE0124700 and 2022YFC3106002。
文摘By establishing a distribution and environmental factor database of 21 typical harmful dinoflagellates in global waters,the MaxEnt model was used to predict shifts in the habitat of harmful dinoflagellates in Chinese waters under global climate change.The results revealed that offshore distance was the most important predictive factor and that surface seawater temperature(SST),primary productivity,and nitrate concentration were the key ecological factors influencing the distribution of harmful dinoflagellates.Under the low greenhouse gas emission scenario defined by the Intergovernmental Panel on Climate Change(IPCC),by approximately 2050,17 of the 21harmful dinoflagellate species in high-suitability areas(HSA)will migrate northward,six species will migrate eastward,and six species will expand their HSA.By 2100,approximately 18 of the 21 harmful dinoflagellate species in HSA will have migrated northward,seven species will have migrated eastward,and four species will have expanded their HSA.Notably,the HSA content of highly toxic Alexandrium minutum is expected to increase by 13.4%and 9.4%by 2050 and 2100,respectively.Under the high greenhouse gas emissions,there will be 17species migrating northward,6 species migrating eastward,and 4 species increasing in their size in HSA by 2050;moreover,there will be 16 species migrating northward,2 migrating eastward,and 4 species according to their size of HSA by 2100.Specifically,the HSA of A.minutum is predicted to increase by 7.0%and 25.9%by 2050 and 2100,respectively.Notably,A.ostenfeldii,which is currently seldom present in the China seas,is predicted to exhibit an HSA in most coastal areas of the Yellow Sea,the Bohai Sea,the Hangzhou Bay,the Zhejiang Coast,and the Beibu Gulf of the South China Sea.Conversely,the HSA of Noctiluca scintillans,a typical red-tide species,will be reduced by 7%–90%.The northward migration of Karenia mikimotoi exceeded 100 km and 300 km under low and high greenhouse gas emission scenarios,respectively.These changes underscore the significant impact of climate change on the distribution and habitat suitability of harmful dinoflagellates,thus indicating a potential shift in their ecological dynamics and consequent effects on marine ecosystems.
基金The Scientific Research Foundation of the Third Institute of Oceanography,Ministry of Natural Resources under contract Nos TIO2020008 and TIO2019028the Project of Marine Protected Areas Network in China-ASEAN Countries,National Key Research and Development Programe under contract No.2017YFC1405100the National Science Foundation of China under contract No.41976050.
文摘Global carbon cycle has received extensive attention,among which the river-estuary system is one of the important links connecting the carbon cycle between land and ocean.In this paper,the distribution and control factors of particulate organic carbon(POC)were studied by using the data of organic carbon contents and its carbon isotopic composition(δ13C)in the mainstream and estuary of Passur River in the Sundarbans area,combined with the hydrological and biological data measured by CTD.The results show that POC content ranged from 0.263 mg/L to 9.292 mg/L,and the POC content in the river section(averaged 4.129 mg/L)was significantly higher than that in the estuary area(averaged 0.858 mg/L).Two distinct stages of POC transport from land to sea in the Sundarbans area were identified.The first stage occurred in the river section,where POC distribution was mainly controlled by the dynamic process of runoff and the organic carbon was mainly terrestrial source.The second stage occurred during estuarine mixing,where the POC distribution was mainly controlled by the mixing process of seawater and freshwater.The source of POC was predominantly marine and exhibiting vertical differences.The surface and middle layers were primarily influenced by marine sources,while the bottom layer was jointly controlled by terrestrial and marine sources of organic carbon.These findings are of great significance for understanding the carbon cycle in such a large mangrove ecosystem like the Sundarbans mangrove.
