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
Based on the survey of surface sediment in Xiamen Bay in October 2011, the speciation, distribution, and potential ecological risk assessment of heavy metals (Cu, Pb, Zn, Cd, and Cr) in this area were studied us-ing...Based on the survey of surface sediment in Xiamen Bay in October 2011, the speciation, distribution, and potential ecological risk assessment of heavy metals (Cu, Pb, Zn, Cd, and Cr) in this area were studied us-ing the sequential extraction method and ecological risk assessment method. The results indicated:(1) the total concentrations of these heavy metals were influenced by runoff, industrial wastewater, and sewage, and were all higher in the coastal area than the offshore area while the highest area of Pb was a little far-ther away from the coastal water due to atmosphere deposition;(2) sequential extractions suggested that Cu was mainly composed with residual and Fe/Mn-oxide bound fractions, Pb was bound to Fe/Mn-oxide, Zn and Cr were dominated by residual, and Cd bound to exchangeable and carbonate fractions; (3) the order of migration and transformation sequence was Cd>Pb>Cu>Zn>Cr and the degree of pollution was Cd>Pb>Cu>Zn>Cr;and (4) the ratios of the secondary and primary phases showed that Zn and Cr were both clean, Cu may be polluted, Pb was moderately polluted, while Cd was heavily polluted.展开更多
As a very important component of a coastal system, tidal flats come to be a focus of the studies on land-ocean interaction in the coastal zone because those areas are subjected to intense human activities and are high...As a very important component of a coastal system, tidal flats come to be a focus of the studies on land-ocean interaction in the coastal zone because those areas are subjected to intense human activities and are highly sensitive to the global change. The Quanzhou Bay, located along the middle part of Fujian coast of China, covers about 136.4km^2, and the area of coastal wetland in the entire bay from intertidal to subtidal with 6m of water depth accounts for 96% of the total area. Seven short cores were collected and divided in situ with the interval of 5cm on the coastal wetlands of Quanzhou Bay on April 19, 2006. The sediment samples were scattered and the grain sizes were measured by using Mastersizer 2000. Human beings' activities on tidal fiat have disturbed the vertical distribution of sediments in stratigraphic sequence and accelerated the sedimentation rates. Grain size analysis results show that the grain size diameters increase and sediment becomes worse sorted towards the sea under the strong human disturbance; Spartina alterniflora can play a role of trapping the fine sediment; but near the bank, the sediment becomes coarse and there are two peak values on frequency curve influenced by the sandpile. The trough formed by human activities along the coastline changes the transport path of water and suspended sediment. The sediments are transported through the trough and deposit in it during the flood; the ebb flow is retarded by the flow output through the adjacent trough, and the deposited sediment can not be re-suspended; then, the sedimentation rate increases. In situ observation show that the sedimentation rate is about 8-10cm/yr.展开更多
Thais luteostoma has been utilized as a crude drug whose shell and soft tissue have been widely used for the treatment of heat syndrome in China for thousands of years. The present study was designed to investigate th...Thais luteostoma has been utilized as a crude drug whose shell and soft tissue have been widely used for the treatment of heat syndrome in China for thousands of years. The present study was designed to investigate the antipyretic and anti-inflammatory activities of T. luteostoma. T. luteostoma was divided into shell (TLSH) and soft tissue (TLST) samples in the present study. The rat model of yeast-induced fever was used to investigate their antipyretic effects; and the rat model of hind paw edema induced by carrageenan was utilized to study their anti-inflammatory activities, and at the same time, the concentration variations of the central neurotransmitter [prostaglandin E2 (PGE2) and cyclic adenosine monophosphate (cAMP)], inflammatory mediators [tumor necrosis factor (TNFα), interleukin-1β (IL-1), interleukin-2 (IL-2) and interleukin-6 (IL-6)] and ion (Na^+ and Ca^2+) were also tested. The results showed that TLSH and TLST extracts significantly inhibited yeast-induced pyrexia in rats (P 〈 0.05), and exhibited more lasting effects as compared to aspirin, and TLSH had the better antipyretic activity than TLST, and that TLSH and TLST could significantly prevent against carrageenan induced paw edema in rats (P 〈 0.05); and markedly reduced levels of PGE2, cAMP, TNFα, IL-1β, IL-2, IL-6, and Na^+/Ca^2+. In fever model, TLST could significantly reduce the levels of PGE2 (P 〈 0.01) in rats' homogenate and TNF a (P 〈 0.05), IL-113 (P 〈 0.01) in the plasma than TLSH, whereas TLSH could reduce the content of IL-2 (P 〈 0.01) and IL-6 (P 〈 0.01) in plasma and increase the content of Ca2+ (P 〈 0.01) in plasma and homogenate more significantly than TLST. In conclusion, T. luteostoma extract has antipyretie and anti-inflammatory activities, which may be mediated through the suppression of production of PGE2, cAMP, Na^+/Ca^2+ , TNF a, IL-1β, IL-2, and IL-6.展开更多
Volcanic rocks in the Bangxi-Chenxing tectonic zone provide important carries for better understanding the Late Paleozoic tectonic evolution in Hainan and its temporal-spatial pattern of the eastern Paleotethyan evolu...Volcanic rocks in the Bangxi-Chenxing tectonic zone provide important carries for better understanding the Late Paleozoic tectonic evolution in Hainan and its temporal-spatial pattern of the eastern Paleotethyan evolution. This paper presents a set of new geochronological and geochemical data on the andesitic and dacitic rocks along the Bangxi-Chenxing tectonic zone in central Hainan. The rep- resentative andesitic and dacitic samples yield similar zircon U-Pb ages of 353^-3 and 351^-7 Ma, respec- tively, being of Early Carboniferous origin. These volcanic rocks are characterized by low TiO2 and high A1203 contents and are enriched in LILEs and LREEs but depletion in HFSEs, along with negative fNd(t) Values of =1.4-- -4.7 and high STSr/S6Sr(i) ratios of 0.707 2-0.710 1. Geochemical signatures suggest that the andesitic and dacitic samples might originate from a metasomatized wedge modified by the slab-derived component in a continental arc setting. In combination with the available data, it is pro- posed for the development of a Carboniferous continental arc in response to the eastern Paleotethyan evolution. The Bangxi-Chenxing tectonic zone might westerly link with the Jinshajiang-Ailaoshan-Song Ma suture zone, constituting an assemblage boundary between the South China and Indochina blocks.展开更多
The Prydz Bay in the Antarctic is an important area in the Southern Ocean due to its unique geographic feature. It plays an important role in the carbon cycle in the Southern Ocean. To investigate the distributions of...The Prydz Bay in the Antarctic is an important area in the Southern Ocean due to its unique geographic feature. It plays an important role in the carbon cycle in the Southern Ocean. To investigate the distributions of carbon dioxide in the atmosphere and surface seawater and its air-sea exchange rates in this region, the Chinese National Antarctic Research Expedition (CHINARE) had set up several sections in the Prydz Bay. Here we present the results from the CHINARE-XVI cruises were presented onboard R/V Xue/ong from November 1999 to April 2000 and the main driving forces were discussed controlling the distributions of partial pressure of carbon dioxide. According to the partial pressure of carbon dioxide distributions, the Prydz Bay can be divided into the inside and outside regions. The partial pressure of carbon dioxide was low in the inside region but higher in the outside region during the measurement period. This distribution had a good negative correlation with the concentrations of ehlorophyll-a in general, suggesting that the partial pressure of carbon dioxide was substantially affected by biological production. The results also indicate that the biological produetion is most likely the main driving force in the marginal ice zone in the Southern Ocean in summer. However, in the Antarctic divergence sector of the Prydz Bay (about 64°S), the hydrological processes become the controlling factor as the sea surface partial pressure of carbon dioxide is much higher than the atmospheric one due to the upwelling of the high DIC CDW, and this made the outside of Prydz Bay a source of carbon dioxide. On the basis of the calculations, the CO2 flux in January (austral summer) was -3.23 mmol/(m^2 · d) in the inner part of Prydz Bay, i.e. , a sink of atmospheric CO2, and was 0.62 mmol/(m^2 · d) in the outside part of the bay, a weak source of atmospheric CO2. The average air-sea flux of CO2 in the Prydz Bay was 2.50 mmol/(m^2 · d).展开更多
Concentrations of total mercury (THg) and methyl mercury (MeHg) were determined for 32 surface sed- iments collected along the coastal line of Fujian Province and eastern Guangdong Province. The spatial distributi...Concentrations of total mercury (THg) and methyl mercury (MeHg) were determined for 32 surface sed- iments collected along the coastal line of Fujian Province and eastern Guangdong Province. The spatial distributions of THg and MeHg and their environmental impact factors were investigated. The average con- centrations of THg and MeHg in the sediments were 31.5 ng/g and 0.096 ng/g, respectively. Both sediment THg and MeHg concentrations showed relatively high value in the Minjiang Estuary and the coastal areas of Quanzhou and Putian. The concentrations overall decreased as the distance to the shoreline increased. The correlations among environmental impact factors and THg, MeHg were analyzed. The sediment THg concentration was highly correlated to the concentrations of organic matter, copper, total nitrogen (TN) and total phosphorus (TP), and significantly correlated to pH value of the bottom seawater and concentration of sediment sulfide. The sediment MeHg concentration was highly correlated to the concentrations of organic matter and copper, and significant correlated to the concentrations of sulfide, TN, TP and pH value of the bottom seawater.展开更多
The phosphatidylinositol 3-kinase(PI3K)-AKT pathway is involved in various cellular functions, including anti-apoptosis, protein synthesis, glucose metabolism and cell cycling. However, the role of the PI3K-AKT pathwa...The phosphatidylinositol 3-kinase(PI3K)-AKT pathway is involved in various cellular functions, including anti-apoptosis, protein synthesis, glucose metabolism and cell cycling. However, the role of the PI3K-AKT pathway in crustaceans remains unclear. In the present study, we cloned and characterized the AKT gene lvakt from Litopenaeus vannamei. The 511-residue LVAKT was highly conserved; contained a PH domain, a catalytic domain and a hydrophobic domain; and was highly expressed in the heart and gills of L. vannamei. We found, using Real-Time Quantitative PCR(Q-PCR) analysis, that lvakt was upregulated during early white spot syndrome virus(WSSV) infection. Moreover, the PI3K-specific inhibitor, LY294002, reduced viral gene transcription, implying that the PI3K-AKT pathway might be hijacked by WSSV. Our results therefore suggest that LVAKT may play an important role in the shrimp immune response against WSSV.展开更多
The tidal flats of the Wanggang area, on the Jiangsu coast, represent the largest continuously distributed coastal wetland in terms of area coverage in China, and the dynamics of tidal flat accretion and erosion is hi...The tidal flats of the Wanggang area, on the Jiangsu coast, represent the largest continuously distributed coastal wetland in terms of area coverage in China, and the dynamics of tidal flat accretion and erosion is highly complicated. The cord-grass Spartina alterniflora, which was introduced artificially into the Jiangsu coast, has significant influences on the regional tidal flat evolution in terms of deposition rate, spacial sediment distribution patterns and tidal creek morphology. On the basis of the data set of bed elevation and accumulation rate for different periods of time, the applicability of the Pethick - Allen model to the Jiangsu tidal salt marshes is discussed. In addition, caesium-137 dating was carried out for sediment samples collected from the salt marsh of the Wangang area. In combination with the caesium-137 analysis and the data collected from literature, the Pethick - Allen model was used to derive the accumulation rate in the Wanggang tidal flat for the various periods. The results show that the pattern of tidal flat accretion has been modified, due to more rapid accretion following the iatroduction of S. alterniflora to the region. Surficial sediment samples were collected from representative profiles and analyzed for grain size with a laser particle analyzer. The result shows that fine-grained sediment has been trapped by the plant, with most of the sediment deposited on the Suaeda salsa and Spartina angelica flats being derived from drainage creeks rather than the from gently sloping tidal flats. Remote sensing analysis and in situ observations indicate that the creeks formed in the S. alterniflora flat have a relatively small ratio of width to depth, a relatively high density, and are more stable than the other tidal flat creek systems in the study area.展开更多
The increases of atmospheric carbon dioxide and other greenhouse gases have caused fundamental changes to the physical and biogeochemical properties of the oceans,and it will continue to occur in the foreseeable futur...The increases of atmospheric carbon dioxide and other greenhouse gases have caused fundamental changes to the physical and biogeochemical properties of the oceans,and it will continue to occur in the foreseeable future.Based on the outputs of nine Earth System Models from the fifth phase of the Coupled Model Intercomparison Project(CMIP5),in this study,we provided a synoptic assessment of future changes in the sea surface temperature(SST),salinity,dissolved oxygen(DO),seawater pH,and marine net primary productivity(NPP)in the coastal China seas over the 21st century.The results show that the mid-high latitude areas of the coastal China seas(East China Seas(ECS),including the Bohai Sea,Yellow Sea,and East China Sea)will be simultaneously exposed to enhanced warming,deoxygenation,acidification,and decreasing NPP as a consequence of increasing greenhouse gas emissions.The magnitudes of the changes will increase as the greenhouse gas concentrations increase.Under the high emission scenario(Representative Concentration Pathway 8.5),the ECS will experience an SST increase of 3.24±1.23℃,a DO concentration decrease of 10.90±3.92μmol/L(decrease of 6.3%),a pH decline of 0.36±0.02,and a NPP reduction of-17.7±6.2 mg/(m2·d)(decrease of 12.9%)relative to the current levels(1980-2005)by the end of this century.The co-occurrence of these changes and their cascade effects are expected to induce considerable biological and ecological responses,thereby making the ECS among the most vulnerable ocean areas to future climate change.Despite high uncertainties,our results have important implications for regional marine assessments.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The Fundamental Research Project of Third Institute Oceanography of State Oceanic Administration under contract No.2011014the Public Welfare Project of the State Oceanic Administration under contract No.2011418015
文摘Based on the survey of surface sediment in Xiamen Bay in October 2011, the speciation, distribution, and potential ecological risk assessment of heavy metals (Cu, Pb, Zn, Cd, and Cr) in this area were studied us-ing the sequential extraction method and ecological risk assessment method. The results indicated:(1) the total concentrations of these heavy metals were influenced by runoff, industrial wastewater, and sewage, and were all higher in the coastal area than the offshore area while the highest area of Pb was a little far-ther away from the coastal water due to atmosphere deposition;(2) sequential extractions suggested that Cu was mainly composed with residual and Fe/Mn-oxide bound fractions, Pb was bound to Fe/Mn-oxide, Zn and Cr were dominated by residual, and Cd bound to exchangeable and carbonate fractions; (3) the order of migration and transformation sequence was Cd>Pb>Cu>Zn>Cr and the degree of pollution was Cd>Pb>Cu>Zn>Cr;and (4) the ratios of the secondary and primary phases showed that Zn and Cr were both clean, Cu may be polluted, Pb was moderately polluted, while Cd was heavily polluted.
基金Under the auspices of the National Natural Science Foundation of China(No.40606012)the Marine Science Youth Fund of State Oceanic Administration of China(No.2006312)the Natural Science Foundation of Fujian Province(No.D0510025)
文摘As a very important component of a coastal system, tidal flats come to be a focus of the studies on land-ocean interaction in the coastal zone because those areas are subjected to intense human activities and are highly sensitive to the global change. The Quanzhou Bay, located along the middle part of Fujian coast of China, covers about 136.4km^2, and the area of coastal wetland in the entire bay from intertidal to subtidal with 6m of water depth accounts for 96% of the total area. Seven short cores were collected and divided in situ with the interval of 5cm on the coastal wetlands of Quanzhou Bay on April 19, 2006. The sediment samples were scattered and the grain sizes were measured by using Mastersizer 2000. Human beings' activities on tidal fiat have disturbed the vertical distribution of sediments in stratigraphic sequence and accelerated the sedimentation rates. Grain size analysis results show that the grain size diameters increase and sediment becomes worse sorted towards the sea under the strong human disturbance; Spartina alterniflora can play a role of trapping the fine sediment; but near the bank, the sediment becomes coarse and there are two peak values on frequency curve influenced by the sandpile. The trough formed by human activities along the coastline changes the transport path of water and suspended sediment. The sediments are transported through the trough and deposit in it during the flood; the ebb flow is retarded by the flow output through the adjacent trough, and the deposited sediment can not be re-suspended; then, the sedimentation rate increases. In situ observation show that the sedimentation rate is about 8-10cm/yr.
基金supported by Marine Industry Research Special Funds for Public Welfare Projects(201205024–1)The Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(ysxk-2010)
文摘Thais luteostoma has been utilized as a crude drug whose shell and soft tissue have been widely used for the treatment of heat syndrome in China for thousands of years. The present study was designed to investigate the antipyretic and anti-inflammatory activities of T. luteostoma. T. luteostoma was divided into shell (TLSH) and soft tissue (TLST) samples in the present study. The rat model of yeast-induced fever was used to investigate their antipyretic effects; and the rat model of hind paw edema induced by carrageenan was utilized to study their anti-inflammatory activities, and at the same time, the concentration variations of the central neurotransmitter [prostaglandin E2 (PGE2) and cyclic adenosine monophosphate (cAMP)], inflammatory mediators [tumor necrosis factor (TNFα), interleukin-1β (IL-1), interleukin-2 (IL-2) and interleukin-6 (IL-6)] and ion (Na^+ and Ca^2+) were also tested. The results showed that TLSH and TLST extracts significantly inhibited yeast-induced pyrexia in rats (P 〈 0.05), and exhibited more lasting effects as compared to aspirin, and TLSH had the better antipyretic activity than TLST, and that TLSH and TLST could significantly prevent against carrageenan induced paw edema in rats (P 〈 0.05); and markedly reduced levels of PGE2, cAMP, TNFα, IL-1β, IL-2, IL-6, and Na^+/Ca^2+. In fever model, TLST could significantly reduce the levels of PGE2 (P 〈 0.01) in rats' homogenate and TNF a (P 〈 0.05), IL-113 (P 〈 0.01) in the plasma than TLSH, whereas TLSH could reduce the content of IL-2 (P 〈 0.01) and IL-6 (P 〈 0.01) in plasma and increase the content of Ca2+ (P 〈 0.01) in plasma and homogenate more significantly than TLST. In conclusion, T. luteostoma extract has antipyretie and anti-inflammatory activities, which may be mediated through the suppression of production of PGE2, cAMP, Na^+/Ca^2+ , TNF a, IL-1β, IL-2, and IL-6.
基金jointly supported by the Projects from China (Nos. U1701641, 41506050, 2016ZT06N331 and 2017M612794)
文摘Volcanic rocks in the Bangxi-Chenxing tectonic zone provide important carries for better understanding the Late Paleozoic tectonic evolution in Hainan and its temporal-spatial pattern of the eastern Paleotethyan evolution. This paper presents a set of new geochronological and geochemical data on the andesitic and dacitic rocks along the Bangxi-Chenxing tectonic zone in central Hainan. The rep- resentative andesitic and dacitic samples yield similar zircon U-Pb ages of 353^-3 and 351^-7 Ma, respec- tively, being of Early Carboniferous origin. These volcanic rocks are characterized by low TiO2 and high A1203 contents and are enriched in LILEs and LREEs but depletion in HFSEs, along with negative fNd(t) Values of =1.4-- -4.7 and high STSr/S6Sr(i) ratios of 0.707 2-0.710 1. Geochemical signatures suggest that the andesitic and dacitic samples might originate from a metasomatized wedge modified by the slab-derived component in a continental arc setting. In combination with the available data, it is pro- posed for the development of a Carboniferous continental arc in response to the eastern Paleotethyan evolution. The Bangxi-Chenxing tectonic zone might westerly link with the Jinshajiang-Ailaoshan-Song Ma suture zone, constituting an assemblage boundary between the South China and Indochina blocks.
基金The National Natural Science Foundation of China under contract Nos40276001,40406014,40676062 and 40531007the Polar StrategyFoundation of under contract No.20070224+3 种基金the National Key Technology Reaserch and Development Program for the11th Five-year Plan of China undercontract No.2006BAB18B04the Fujian Province Youth Technological Creation of China under contract No.2004J056Fujian Province Natural Science Foundation of China under contract No.Z0513027TIOSOA Foundation
文摘The Prydz Bay in the Antarctic is an important area in the Southern Ocean due to its unique geographic feature. It plays an important role in the carbon cycle in the Southern Ocean. To investigate the distributions of carbon dioxide in the atmosphere and surface seawater and its air-sea exchange rates in this region, the Chinese National Antarctic Research Expedition (CHINARE) had set up several sections in the Prydz Bay. Here we present the results from the CHINARE-XVI cruises were presented onboard R/V Xue/ong from November 1999 to April 2000 and the main driving forces were discussed controlling the distributions of partial pressure of carbon dioxide. According to the partial pressure of carbon dioxide distributions, the Prydz Bay can be divided into the inside and outside regions. The partial pressure of carbon dioxide was low in the inside region but higher in the outside region during the measurement period. This distribution had a good negative correlation with the concentrations of ehlorophyll-a in general, suggesting that the partial pressure of carbon dioxide was substantially affected by biological production. The results also indicate that the biological produetion is most likely the main driving force in the marginal ice zone in the Southern Ocean in summer. However, in the Antarctic divergence sector of the Prydz Bay (about 64°S), the hydrological processes become the controlling factor as the sea surface partial pressure of carbon dioxide is much higher than the atmospheric one due to the upwelling of the high DIC CDW, and this made the outside of Prydz Bay a source of carbon dioxide. On the basis of the calculations, the CO2 flux in January (austral summer) was -3.23 mmol/(m^2 · d) in the inner part of Prydz Bay, i.e. , a sink of atmospheric CO2, and was 0.62 mmol/(m^2 · d) in the outside part of the bay, a weak source of atmospheric CO2. The average air-sea flux of CO2 in the Prydz Bay was 2.50 mmol/(m^2 · d).
基金Speciation Analysis of Hg in the Sediment of Taiwan Strait under contract No. 2009023the National 908 Surveys of Marine Chemistry in Coastal Waters (908-ZC-I-03)the Fujian Provincial Surveys of Marine Chemistry in Coastal Waters and Harbors under contract No.FJ908-04-07
文摘Concentrations of total mercury (THg) and methyl mercury (MeHg) were determined for 32 surface sed- iments collected along the coastal line of Fujian Province and eastern Guangdong Province. The spatial distributions of THg and MeHg and their environmental impact factors were investigated. The average con- centrations of THg and MeHg in the sediments were 31.5 ng/g and 0.096 ng/g, respectively. Both sediment THg and MeHg concentrations showed relatively high value in the Minjiang Estuary and the coastal areas of Quanzhou and Putian. The concentrations overall decreased as the distance to the shoreline increased. The correlations among environmental impact factors and THg, MeHg were analyzed. The sediment THg concentration was highly correlated to the concentrations of organic matter, copper, total nitrogen (TN) and total phosphorus (TP), and significantly correlated to pH value of the bottom seawater and concentration of sediment sulfide. The sediment MeHg concentration was highly correlated to the concentrations of organic matter and copper, and significant correlated to the concentrations of sulfide, TN, TP and pH value of the bottom seawater.
基金Supported by the Scientific Research Foundation of Third Institute of Oceanography,SOA(No.2011018)the Natural Science Foundation of Fujian Province of China(No.2011J05079)+3 种基金the National Natural Science Foundation of China(No.31001125)the Major State Basic Research Development Program of China(973 Program)(No.2012CB114403)the National High Technology Research and Development Program of China(863 Program)(No.2012AA092205)the China Agriculture Research System-47
文摘The phosphatidylinositol 3-kinase(PI3K)-AKT pathway is involved in various cellular functions, including anti-apoptosis, protein synthesis, glucose metabolism and cell cycling. However, the role of the PI3K-AKT pathway in crustaceans remains unclear. In the present study, we cloned and characterized the AKT gene lvakt from Litopenaeus vannamei. The 511-residue LVAKT was highly conserved; contained a PH domain, a catalytic domain and a hydrophobic domain; and was highly expressed in the heart and gills of L. vannamei. We found, using Real-Time Quantitative PCR(Q-PCR) analysis, that lvakt was upregulated during early white spot syndrome virus(WSSV) infection. Moreover, the PI3K-specific inhibitor, LY294002, reduced viral gene transcription, implying that the PI3K-AKT pathway might be hijacked by WSSV. Our results therefore suggest that LVAKT may play an important role in the shrimp immune response against WSSV.
基金supported financially by the National Natural Science Foundation of China under contract Nos 40231010 and 40476041the Marine Science Youth Fund of State 0ceanic Administration of China under contract No.2006312.
文摘The tidal flats of the Wanggang area, on the Jiangsu coast, represent the largest continuously distributed coastal wetland in terms of area coverage in China, and the dynamics of tidal flat accretion and erosion is highly complicated. The cord-grass Spartina alterniflora, which was introduced artificially into the Jiangsu coast, has significant influences on the regional tidal flat evolution in terms of deposition rate, spacial sediment distribution patterns and tidal creek morphology. On the basis of the data set of bed elevation and accumulation rate for different periods of time, the applicability of the Pethick - Allen model to the Jiangsu tidal salt marshes is discussed. In addition, caesium-137 dating was carried out for sediment samples collected from the salt marsh of the Wangang area. In combination with the caesium-137 analysis and the data collected from literature, the Pethick - Allen model was used to derive the accumulation rate in the Wanggang tidal flat for the various periods. The results show that the pattern of tidal flat accretion has been modified, due to more rapid accretion following the iatroduction of S. alterniflora to the region. Surficial sediment samples were collected from representative profiles and analyzed for grain size with a laser particle analyzer. The result shows that fine-grained sediment has been trapped by the plant, with most of the sediment deposited on the Suaeda salsa and Spartina angelica flats being derived from drainage creeks rather than the from gently sloping tidal flats. Remote sensing analysis and in situ observations indicate that the creeks formed in the S. alterniflora flat have a relatively small ratio of width to depth, a relatively high density, and are more stable than the other tidal flat creek systems in the study area.
基金Supported by the National Key R&D Program of China(Nos.2017YFA0604901,2017YFA0604902)the Scientific Research Foundation of the Third Institute of Oceanography,Ministry of Natural Resources,China(No.TIO2017030)the Major Project of National Social Science Foundation(No.17ZDA172)。
文摘The increases of atmospheric carbon dioxide and other greenhouse gases have caused fundamental changes to the physical and biogeochemical properties of the oceans,and it will continue to occur in the foreseeable future.Based on the outputs of nine Earth System Models from the fifth phase of the Coupled Model Intercomparison Project(CMIP5),in this study,we provided a synoptic assessment of future changes in the sea surface temperature(SST),salinity,dissolved oxygen(DO),seawater pH,and marine net primary productivity(NPP)in the coastal China seas over the 21st century.The results show that the mid-high latitude areas of the coastal China seas(East China Seas(ECS),including the Bohai Sea,Yellow Sea,and East China Sea)will be simultaneously exposed to enhanced warming,deoxygenation,acidification,and decreasing NPP as a consequence of increasing greenhouse gas emissions.The magnitudes of the changes will increase as the greenhouse gas concentrations increase.Under the high emission scenario(Representative Concentration Pathway 8.5),the ECS will experience an SST increase of 3.24±1.23℃,a DO concentration decrease of 10.90±3.92μmol/L(decrease of 6.3%),a pH decline of 0.36±0.02,and a NPP reduction of-17.7±6.2 mg/(m2·d)(decrease of 12.9%)relative to the current levels(1980-2005)by the end of this century.The co-occurrence of these changes and their cascade effects are expected to induce considerable biological and ecological responses,thereby making the ECS among the most vulnerable ocean areas to future climate change.Despite high uncertainties,our results have important implications for regional marine assessments.