Coral reefs worldwide are losing their species diversity and ecosystem function under threats from global warming and anthropogenic activities.In this study,we investigated the diversity and current state of scleracti...Coral reefs worldwide are losing their species diversity and ecosystem function under threats from global warming and anthropogenic activities.In this study,we investigated the diversity and current state of scleractinian corals surrounding the Qizhou Archipelago.A total of 87 species of scleractinian corals,belonging to 29 genera and 12 families,were found across ten survey sites.The family Merulinidae exhibited the highest species richness(39 species and 12 genera),followed by Acroporidae(15 species and 3genera).The living coral coverage was 16.9%±10.3%(mean±SD)and ranged from 4.6%to 35.1%,which varied significantly.Massive corals such as Porites lutea,Porites lobata,Montipora nodosa,and Favites abdita were dominant species.The recruitment rate of coral larvae was(1.20±0.97)ind/m^(2)(mean±SD).In addition,we constructed an ecological vulnerability assessment system and evaluated the ecological vulnerability of scleractinian corals surrounding the Qizhou Archipelago.The results showed that scleractinian corals at Gouluanpaoshi(GLPS)and Duifan(DF)were highly vulnerable,whereas those on other islands had low to medium vulnerability.In general,the scleractinian corals surrounding the Qizhou Archipelago show low to medium levels of ecological vulnerability.Identifying severely afflicted areas and developing effective methods to manage coral reefs in these regions are crucial.展开更多
Coral gardening has become a promising technique for restoring reefs worldwide in the Anthropocene era.The microbiome plays an important role in enhancing adaptive resilience in situ nursery propagation of corals.Howe...Coral gardening has become a promising technique for restoring reefs worldwide in the Anthropocene era.The microbiome plays an important role in enhancing adaptive resilience in situ nursery propagation of corals.However,little is known about the response patterns of bacterial community dynamics,co-occurrence networks and assembly processes of different species in coral restoration nurseries over time.Here,we collected two Acropora coral samples from transplanted fragments and source colonies at 1-month and 3-month post-transplantation(May and July 2022)in an upwelling-affected fragmented reef.Full-length 16S rRNA gene sequencing revealed that bacterial communities of coral fragments in nurseries exhibited consistent temporal shifts compared to those of the source colonies.High host specificity was observed in the bacterial community and network structure associated with source colonies.In contrast,for the two coral species within nurseries,there were no differences in bacterial diversity,composition and core microbiome.Stochastic assembly processes were identified as the primary drivers of bacterial communities in all May samples,whereas deterministic processes played a more prominent role in July.Seawater properties(e.g.,temperature and ammonium concentration)partially explained the compositional changes in the bacterial communities of these coral samples.Our findings suggested that coral nurseries contributed to the homogenization of bacterial communities in different Acropora corals,despite the apparent temporal dynamics of bacteria.These results enhance our understanding of the coral microbiome,ecological interactions and assembly principles in different host within in situ nurseries.展开更多
The utilization of discarded coral debris in cementitious material is a prominent research area for island construction projects.The aim of this study is to explore the use of environment-friendly cement and waste cor...The utilization of discarded coral debris in cementitious material is a prominent research area for island construction projects.The aim of this study is to explore the use of environment-friendly cement and waste coral sand in the preparation of coral mortar,while investigating its performance when exposed to a chloride environment.Three types of low-carbon cements were employed,such as rapid hardening sulphoaluminate(RCSA)cement,high belite sulphoaluminate(HBCSA)cement,and slag sulphoaluminate cement(SSC).The coulomb electric flux,mechanical properties,free chloride content,and mass change of the cement mortar under exposed to 3.5 wt%NaCl solution were examined at various time intervals.X-ray diffraction analysis was conducted to identify the mineral phases present in the mortar samples.The results demonstrate that the flexural and compressive strength of the mortar consistently increase throughout the 360 days chloride exposure period.Incorporating coral sand into SSC-based mortars enhances their compressive strength from day 28 up until day 360.However,it adversely affects the strength of HBCSA-based mortars.The behavior of mortars exposed to a chloride-rich environment is closely associated with the amount of C-S-H gel present within them.SSC generates a significant quantity of C-S-H gel which possesses a large specific surface area capable of absorbing more chloride ions thereby reducing their concentration within the mortar matrix as well as increasing its mass and improving resistance against chloride ion penetration.展开更多
Crushing waste coral concrete into recycled aggregates to create recycled coral aggregate concrete(RCAC)contributes to sustainable construction development on offshore islands and reefs.To investigate the impact of re...Crushing waste coral concrete into recycled aggregates to create recycled coral aggregate concrete(RCAC)contributes to sustainable construction development on offshore islands and reefs.To investigate the impact of recycled coral aggregate on concrete properties,this study performed a comprehensive analysis of the physical properties of recycled coral aggregate and the basic mechanical properties and microstructure of RCAC.The test results indicate that,compared to coral debris,the crushing index of recycled coral aggregate was reduced by 9.4%,while porosity decreased by 33.5%.Furthermore,RCAC retained the early strength characteristics of coral concrete,with compressive strength and flexural strength exhibiting a notable increase as the water-cement ratio decreased.Under identical conditions,the compressive strength and flexural strength of RCAC were 12.7% and 2.5% higher than coral concrete's,respectively,with porosity correspondingly reduced from 3.13% to 5.11%.This enhancement could be attributed to the new mortar filling the recycled coral aggregate.Scanning electron microscopy(SEM)analysis revealed three distinct interface transition zones within RCAC,with the‘new mortar-old mortar’interface identified as the weakest.The above findings provided a reference for the sustainable use of coral concrete in constructing offshore islands.展开更多
The boron isotope paleo-pH proxy has been extensively studied due to its potential for understanding past climate change, and further calibrations were considered for accurate applications of the proxy because of sign...The boron isotope paleo-pH proxy has been extensively studied due to its potential for understanding past climate change, and further calibrations were considered for accurate applications of the proxy because of significant variability related to biocarbonate microstructure. In this work, we studied the boron isotopic fractionation between modern marine corals and their coexisting seawater collected along shallow area in Sanya Bay, South China Sea. The apparent partition coefficient of boron（KD） ranged from 0.83×10-3 to 1.69×10-3, which are in good agreement with previous studies. As the analyzed coral skeleton（~5 g） spanned the growth time period of 1–2 years, we discussed the boron isotopic fractionation between pristine corals and modern seawater using the annual mean seawater pH of 8.12 in this sea area. Without taking the vital effect into account,（11B/10B）coral values of all living corals spread over the curves of（11B/10B）borate vs.（11B/10B）sw with the α4-3 values ranging from 0.974 to 0.982. After calibrating the biological effect on the calcifying fluid pH, the field-based calcification on calcifying fluid pH（i.e., Δ（pHbiol-pHsw）） for coral species of Acropora, Pavona, Pocillopora, Faviidae, and others including Proites are 0.42, 0.33, 0.36, 0.19, respectively, and it is necessary to be validated by coral culturing experiment in the future. Correlations in B/Ca vs. Sr/Ca and B/Ca vs. pHbiol approve temperature and calcifying fluid pH influence on skeletal B/Ca. Fundamental understanding of the thermodynamic basis of the boron isotopes in marine carbonates and seawater will strengthen the confidence in the use of paleo-pH proxy as a powerful tool to monitor atmospheric CO2 variations in the past.展开更多
Barium to calcium （Ba/Ca） ratio in corals has been considered as a useful geochemical proxy for upwelling,river flood and other oceanic processes.However,recent studies indicated that additional environmental or bio...Barium to calcium （Ba/Ca） ratio in corals has been considered as a useful geochemical proxy for upwelling,river flood and other oceanic processes.However,recent studies indicated that additional environmental or biological factors can influence the incorporation of Ba into coral skeletons.In this study,Ba/Ca ratios of two Porites corals collected from Daya Bay,northern South China Sea were analyzed.Ba/Ca signals in the two corals were ‘anomalous’ in comparison with Ba behaviors seen in other near-shore corals influenced by upwelling or riverine runoff.Our Ba/Ca profiles displayed similar and remarkable patterns characterized by low and randomly fluctuating background signals periodically interrupted by sharp and large synchronous peaks,clearly indicating an environmental forcing.Further analysis indicated that the Ba/Ca profiles were not correlated with previously claimed environmental factors such as precipitation,coastal upwelling,anthropogenic activities or phytoplankton blooms in other areas.The maxima of Ba/Ca appeared to occur in the period of Sr/Ca maxima,coinciding with the winter minimum temperatures,which suggests that the anomalous high Ba/Ca signals were related to winter-time low sea surface temperature.We speculated that the Ba/Ca peaks in corals of the Daya Bay were most likely the results of enrichment of Ba-rich particles in their skeletons when coral polyps retracted under the stresses of anomalous winter low temperatures.In this case,Ba/Ca ratio in relatively high-latitude corals can be a potential proxy for tracing the low temperature stress.展开更多
The 4.2 ka event that occurred during the period from 4 500–3 900 a BP was characterized by cold and dry climates and resulted in the collapse of civilizations around the world. The cause of this climatic event, howe...The 4.2 ka event that occurred during the period from 4 500–3 900 a BP was characterized by cold and dry climates and resulted in the collapse of civilizations around the world. The cause of this climatic event, however, has been under debate. We collected four corals(Porites lutea) from Yongxing Island, Xisha Islands, South China Sea, dated them with the U-series method, and measured the annual coral growth rates using X-ray technology. The dating results showed that the coral growth ages were from 4 500–3 900 a BP, which coincide well with the period of the4.2 ka event. We then reconstructed annual sea surface temperature anomaly(SSTA) variations based on the coral growth rates. The growth rate-based SSTA results showed that the interdecadal SSTA from 4 500–3 900 a BP was lower than that during modern times(1961–2008 AD). A spectral analysis showed that the SSTA variations from4 500–3 900 a BP were under the influence of El Nino-Southern Oscillation(ENSO) activities. From 4 500–4 100 a BP, the climate exhibited La Nina-like conditions with weak ENSO intensity and relatively stable and lower SSTA amplitudes. From 4 100–3 900 a BP, the climate underwent a complicated period of ENSO variability and showed alternating El Nino-or La Nina-like conditions at interdecadal time scales and large SSTA amplitudes. We speculate that during the early and middle stages of the 4.2 ka event, the cold climate caused by weak ENSO activities largely weakened social productivity. Then, during the end stages of the 4.2 ka event, the repeated fluctuations in the ENSO intensity caused frequent extreme weather events, resulting in the collapse of civilizations worldwide. Thus, the new evidence obtained from our coral records suggests that the 4.2 ka event as well as the related collapse of civilizations were very likely driven by ENSO variability.展开更多
Symbiotic algae （Symbiodinium sp.） in scleractinian corals are important in understanding how coral reefs will respond to global climate change. The present paper reports on the diversity of Symbiodinium sp. in 48 s...Symbiotic algae （Symbiodinium sp.） in scleractinian corals are important in understanding how coral reefs will respond to global climate change. The present paper reports on the diversity of Symbiodinium sp. in 48 scleractinian coral species from 25 genera and 10 families sampled from the Xisha Islands in the South China Sea, which were identified with the use of restriction fragment length polymorphism （RFLP） of the nuclear ribosomal DNA large subunit gene （rDNA）. The results showed that： （i） Symbiodinium Clade C was the dominant zooxanthellae in scleractinian corals in the Xisha Islands; （ii） Symbiodinium Clade D was found in the corals Montipora aequituberculata, Galaxea fascicularis, and Plerogyra sinuosa; and （iii） both Symbiodinium Clades C and D were found simultaneously in Montipora digitata, Psammocora contigua, and Galaxeafascicularis. A poor capacity for symbiosis polymorphism, as uncovered by RFLP, in the Xisha Islands indicates that the scleractinian corals have low adaptability to environmental changes. Further studies are needed to investigate zooxanthellae diversity using other molecular markers.展开更多
It has been reported that global warming has negative effects on coral ecosystems in the past 50 years and the effects vary in different ocean environment. In order to make clear the coral reef status in the backgroun...It has been reported that global warming has negative effects on coral ecosystems in the past 50 years and the effects vary in different ocean environment. In order to make clear the coral reef status in the background of global warming along the south coast of Hainan Island of China, satellite and in situ data are used to retrieve the information of the coral reef status and surrounding environmental factors. The results show that cool water induced by upwelling along the south coast of Hainan Island is found in the area every summer month, especially in the relatively strong El Ni？o years（2002–2003 and 2005）. From the NOAA satellite data, degree heating week（DHW） index does not exceed 3 in Sanya Bay even in the relatively strong El Ni？o years. By comparison of a coral reef growth rate in the Sanya Bay with respect to El Ni？o events from 1957 to 2000, coral＇s growth rate is relatively greater during 1972, 1991–1994 and 1998 El Ni？o event. By analyzing the environmental factors, it is found that the cool water induced by upwelling may be the main reason for protecting corals from global warming effects.展开更多
Three deep-sea black corals belonging to the family Schizopathidae,are reported from two seamounts on the Caroline Ridge in the tropical Western Pacific:Umbellapathes parva sp.nov.with depth of 1488-1766 m,Telopathes ...Three deep-sea black corals belonging to the family Schizopathidae,are reported from two seamounts on the Caroline Ridge in the tropical Western Pacific:Umbellapathes parva sp.nov.with depth of 1488-1766 m,Telopathes cf.magna MacIsaac&Best,2013 with depth of 937-1016 m,and Stauropathes cf.punctata(Roule,1905)with depth of 942-1353 m.The latter two species are the first records in the Western Pacific Ocean.U.parva sp.nov.is characterized by monopodial corallum,relatively long unpinnulated stalk with complex pinnulated branche s developing from the lowermost primary pinnules and small spine s.It differs from two known congeners by much smaller spine s and the present of secondary pinnules.T.cf.magna MacIsaac&Best,2013 has sparsely branched corallum,relatively long and simple pinnules arranged in subopposite or alternate pairs.S.cf.punctata(Roule,1905)is characterized by the corallum with almost planar pinnulated branches,and pinnules arranged in subopposite pairs.Our results indicate that the corallum size and shape are variable in conspecific specimens particularly those at different growth stages.By contrast,the size of the polypar spines as well as the abpolypar spines have little variation and can be served as a main differing feature for schizopathid species.The phylogenetic analyses using nuclear internal transcribed spacer region(spanning partial 18 S rDNA,ITS 1,5.8 S,ITS2,and partial 28 S rDNA)and two mitochondrial fragments cox3-IGR-coxl(COI)and trnW-IGR-nad2(NAD2)showed Telopathes,Stau ropathes,and Bathypathes had close relationships,and Umbellapathes formed a sister clade with Alternatipathes.展开更多
The author traced the history of the thirty years of study of the Vietnamese reefs since the second half of the 20th century up to the present time. This paper describes the types of reefs, taxonomic composition and s...The author traced the history of the thirty years of study of the Vietnamese reefs since the second half of the 20th century up to the present time. This paper describes the types of reefs, taxonomic composition and structure of Scleractinian reef ecosystems. It is shown that due to a high level of diverse knowledge revealed, high species richness of coral fauna of Vietnam (376 species of 80 genera) is a single point of origin coral fauna Indo-Pacific. Analysis of knowledge of Vietnamese corals and reefs revealed the extent of their positive or negative status under anthropogenic influence or under the level of wilderness protection, experiment on artificial cultivation of corals and the re-establishment of a coral community.展开更多
Soft corals are well-known as excellent sources of marine-derived natural products.Among them,members of the genera Sar-cophyton,Sinularia,and Lobophytum are especially attractive targets for marine natural product re...Soft corals are well-known as excellent sources of marine-derived natural products.Among them,members of the genera Sar-cophyton,Sinularia,and Lobophytum are especially attractive targets for marine natural product research.In this review,we reported the marine-derived natural products called cembranoids isolated from soft corals,including the genera Sarcophyton,Sinularia,and Lobophytum.Here,we reviewed 72 reports published between 2016 and 2020,comprising 360 compounds,of which 260 are new compounds and 100 are previously known compounds with newly recognized activities.The novelty of the organic molecules and their relevant biological activities,delivered by the year of publication,are presented.Among the genera presented in this report,Sarcophyton spp.produce the most cembranoid diterpenes;thus,they are considered as the most important soft corals for marine natural product research.Cembranoids display diverse biological activities,includ-ing anti-cancer,anti-bacterial,and anti-inflammatory.As cembranoids have been credited with a broad range of biological activities,they present a huge potential for the development of various drugs with potential health and ecological benefits.展开更多
Coral samples collected from the waters off the Leizhou Peninsula, the Hainan Island and the Yongxing Island of the Xisha Islands were analyzed by thermal ionization mass spectrometry (TIMS) and multi-collector induct...Coral samples collected from the waters off the Leizhou Peninsula, the Hainan Island and the Yongxing Island of the Xisha Islands were analyzed by thermal ionization mass spectrometry (TIMS) and multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) for their U-Th systematics. Their uranium contents are mostly lower than 3μg/g, and the δ+{234}U(T) values are within the range of 150±5. X-ray diffraction analysis showed that the corals are all composed of aragonite. This demonstrates that the corals determined have maintained a close system for 7000 years and their skeletons bear much information about the primitive tropical marine environment. The highly precise age sequence of the corals determined has revealed that there occurred three phases of high sea level in the South China Sea waters, which are dated at 6799-6307 a B.P., 4472-4285 a B.P. and 1279-1012 a B.P., respectively. The three phases lasted 492 a, 187 a and 267 a, respectively. These three phases of high sea level are corresponding to the warm environments that had appeared in China during the Megathermal Period and the Medieval Warm Period in the past ten thousand years.展开更多
The existing hermatypic coral community is composed of localities in different successional ages.Data sets were selected from original sampling data to deduce the trajectory of community structure in this and subseque...The existing hermatypic coral community is composed of localities in different successional ages.Data sets were selected from original sampling data to deduce the trajectory of community structure in this and subsequent papers.Patterns of species composition and abundance distribution during community succession in the scope of different habitats were described in this paper.It is found that the effect of succession on community structure is closely correlated with the environmental conditions.Each coral assemblage in different habitat has its own distinguishing temporal pattern of species composition and abundance distribution.展开更多
The paper analyzes both published and unpublished results of the investigations of Vietnamese reef building corals and reefs performed in the last decades of the twentieth century and first decades twenty-first. The s...The paper analyzes both published and unpublished results of the investigations of Vietnamese reef building corals and reefs performed in the last decades of the twentieth century and first decades twenty-first. The state of the art in the study of reef-building scleractinian corals and reefs is presented. The scleractinian fauna of Vietnam is shown to match in species diversity (350 species of 80 genera) the tropical coral fauna of the Indonesian–Malacca fertile center, from which Indo-Pacific reef-building corals originated. The whole Vietnam coast from the Gulf of Tonkin to the Gulf of Siam is a biogeographically single whole and is a part of the Indo-Polynesian Province of the Indo-Pacific Area.展开更多
OBJECTIVE To identify and characterize a novel neuroprotective ShK peptide and its analogue originated from coral P.caribaeoru.METHODS P.caribaeoru was collected and subjected to transcriptome sequencing at which furt...OBJECTIVE To identify and characterize a novel neuroprotective ShK peptide and its analogue originated from coral P.caribaeoru.METHODS P.caribaeoru was collected and subjected to transcriptome sequencing at which further bioinformatics analysis had identified a unigene encoding a putative ShK protein candidate,named as PcShK1.PcShK1 and its rhodamine derivative(PcShK1-RhoB) were synthesized and tested for the neuroprotective effect in 6-OHDA induced Parkinson disease models in vitro and in vivo.Briefly,zebrafish larvae were co-exposed to 6-OHDA and various doses of the peptides;then,dopaminergic(DA) neurons immunoreactivity and locomotion behavior of the zebrafish larvae were examined.Similarly,PC12 cells were cultured with 6-OHDA in the absence or presence of different concentrations of peptides.Cell viability was determined by MTT assay while calcium flow in the PC12 cells was monitored by Fluo-4 fluorescent dye.RESULTS Compared with control group,6-OHDA treatment could lead to DA neurons loss and locomotion deficits in PD model of zebrafish larvae(P<0.01).Both PcS hK 1(2.5,5.0 and 7.5 μmol·L^(-1)) and PcS hK 1-RhoB(0.50 and 0.75 μmol·L^(-1)) were found to protect and restore dopaminergic neurons from6-OHDA mediated injury and locomotion deficiency in the PD zebrafish respectively(P<0.01).In addition,PcShK1(2.5 to 20.0 μmol·L^(-1)) and PcShK1-RhoB(0.6 to 2.5 μmol·L^(-1)) effectively prevented against 6-OHDA toxicity in PC12 cells(P<0.01).Further study revealed that they might exert their neuroprotective effects through regulating the calcium homeostasis.CONCLUSION PcS hK 1 and PcS hK 1-RhoB show neuroprotective effects on 6-OHDA induced PD models,and the underlying protective mechanisms of these peptides probably involve calcium homeostasis regulation.展开更多
Scleractinian corals appeared during the Anisian period of the Triassic after the end-Permian mass extinction, which in Triassic were distinct from the Jurassic-Cretaceous scleractinian corals. The study on Triassic s...Scleractinian corals appeared during the Anisian period of the Triassic after the end-Permian mass extinction, which in Triassic were distinct from the Jurassic-Cretaceous scleractinian corals. The study on Triassic scleractinian coral fauna as a separate field is significant for exploring the development and evolution of modern corals and investigating environmental changes since the Mesozoic. The first Triassic coral in China was reported in 1925, and since then, nearly 25 articles dealing with taxonomy and 17 papers about fossil reports on Triassic scleractinian corals in China have been published, which refer to 60 genera and 312 species, 49 localities and 25 strata. In this paper, the history, taxonomy, localities, stratigraphic distribution, current research, and existing knowledge gaps of the Triassic scleractinian corals in China are reviewed. More specifically, the research findings of the Triassic scleractinain coral in China since 1925 are discussed; the species of the Triassic scleractian coral fossil reported in China, has been examined and its synonyms have been sorted out; the geographical distributions of the Middle and Late Triassic scleractinian corals in China are systematically treated; the Triassic coral biostratigraphy in China has been improved; and the stratigraphic ranges of existing genera and species are provided. The above conclusions are presented in the form of complete figures. At the same time, we analyzed shortcomings in current research and identified productive future research directions of the Triassic scleractinian corals in China.展开更多
The end-Triassic （also Triassic-Jurassic） mass extinction severely affected life on planet Earth 200 million years ago. Paleoclimate change triggered by the volcanic eruptions of the Central Atlantic Magmatic Provin...The end-Triassic （also Triassic-Jurassic） mass extinction severely affected life on planet Earth 200 million years ago. Paleoclimate change triggered by the volcanic eruptions of the Central Atlantic Magmatic Province （CAMP） caused a great loss of marine biodiversity, among which 96% coral genera were get lost. However, there is precious little detail on the paleoecology and growth forms lost between the latest Triassic extinction and the Early Jurassic recovery. Here a new pilot study was conducted by analyzing corallite integration levels among corals from the latest Triassic and Early Jurassic times. Integration levels in corals from the Late Triassic and Early Jurassic were determined through both the Paleobiology Database as well as from a comprehensive museum collection of fossil corals. Results suggest that in addition to a major loss of diversity following the end-Triassic mass extinction, there also was a significant loss of highly integrated corals as clearly evidenced by the coral data from the Early Jurassic. This confirms our hypothesis of paleoecological selectivity for corals following the end-Triassic mass extinction. This study highlights the importance of assigning sim- ple to advanced paleoecological characters with integration levels, which opens a useful approach to understanding of mass extinction and the dynamics of the recovery.展开更多
基金funded by the Scientific Research Foundation of Third Institute of Oceanography,Ministry of Natural Resources(Nos.2022024 and 2020006)the National Natural Science Foundation of China(No.42106143)。
文摘Coral reefs worldwide are losing their species diversity and ecosystem function under threats from global warming and anthropogenic activities.In this study,we investigated the diversity and current state of scleractinian corals surrounding the Qizhou Archipelago.A total of 87 species of scleractinian corals,belonging to 29 genera and 12 families,were found across ten survey sites.The family Merulinidae exhibited the highest species richness(39 species and 12 genera),followed by Acroporidae(15 species and 3genera).The living coral coverage was 16.9%±10.3%(mean±SD)and ranged from 4.6%to 35.1%,which varied significantly.Massive corals such as Porites lutea,Porites lobata,Montipora nodosa,and Favites abdita were dominant species.The recruitment rate of coral larvae was(1.20±0.97)ind/m^(2)(mean±SD).In addition,we constructed an ecological vulnerability assessment system and evaluated the ecological vulnerability of scleractinian corals surrounding the Qizhou Archipelago.The results showed that scleractinian corals at Gouluanpaoshi(GLPS)and Duifan(DF)were highly vulnerable,whereas those on other islands had low to medium vulnerability.In general,the scleractinian corals surrounding the Qizhou Archipelago show low to medium levels of ecological vulnerability.Identifying severely afflicted areas and developing effective methods to manage coral reefs in these regions are crucial.
基金The Innovative Talent Foundation of Hainan Province under contract No.KJRC2023C39the National Natural Science Foundation of China under contract Nos 42161144006 and 42076108.
文摘Coral gardening has become a promising technique for restoring reefs worldwide in the Anthropocene era.The microbiome plays an important role in enhancing adaptive resilience in situ nursery propagation of corals.However,little is known about the response patterns of bacterial community dynamics,co-occurrence networks and assembly processes of different species in coral restoration nurseries over time.Here,we collected two Acropora coral samples from transplanted fragments and source colonies at 1-month and 3-month post-transplantation(May and July 2022)in an upwelling-affected fragmented reef.Full-length 16S rRNA gene sequencing revealed that bacterial communities of coral fragments in nurseries exhibited consistent temporal shifts compared to those of the source colonies.High host specificity was observed in the bacterial community and network structure associated with source colonies.In contrast,for the two coral species within nurseries,there were no differences in bacterial diversity,composition and core microbiome.Stochastic assembly processes were identified as the primary drivers of bacterial communities in all May samples,whereas deterministic processes played a more prominent role in July.Seawater properties(e.g.,temperature and ammonium concentration)partially explained the compositional changes in the bacterial communities of these coral samples.Our findings suggested that coral nurseries contributed to the homogenization of bacterial communities in different Acropora corals,despite the apparent temporal dynamics of bacteria.These results enhance our understanding of the coral microbiome,ecological interactions and assembly principles in different host within in situ nurseries.
基金Funded by the National Natural Science Foundation of China(No.51708290)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘The utilization of discarded coral debris in cementitious material is a prominent research area for island construction projects.The aim of this study is to explore the use of environment-friendly cement and waste coral sand in the preparation of coral mortar,while investigating its performance when exposed to a chloride environment.Three types of low-carbon cements were employed,such as rapid hardening sulphoaluminate(RCSA)cement,high belite sulphoaluminate(HBCSA)cement,and slag sulphoaluminate cement(SSC).The coulomb electric flux,mechanical properties,free chloride content,and mass change of the cement mortar under exposed to 3.5 wt%NaCl solution were examined at various time intervals.X-ray diffraction analysis was conducted to identify the mineral phases present in the mortar samples.The results demonstrate that the flexural and compressive strength of the mortar consistently increase throughout the 360 days chloride exposure period.Incorporating coral sand into SSC-based mortars enhances their compressive strength from day 28 up until day 360.However,it adversely affects the strength of HBCSA-based mortars.The behavior of mortars exposed to a chloride-rich environment is closely associated with the amount of C-S-H gel present within them.SSC generates a significant quantity of C-S-H gel which possesses a large specific surface area capable of absorbing more chloride ions thereby reducing their concentration within the mortar matrix as well as increasing its mass and improving resistance against chloride ion penetration.
基金Funded by Natural Science Foundation of Guangxi(No.2025GXNSFBA069565)Guangxi Science and Technology Program(No.AD25069101)Guangxi Bagui Scholars Fund。
文摘Crushing waste coral concrete into recycled aggregates to create recycled coral aggregate concrete(RCAC)contributes to sustainable construction development on offshore islands and reefs.To investigate the impact of recycled coral aggregate on concrete properties,this study performed a comprehensive analysis of the physical properties of recycled coral aggregate and the basic mechanical properties and microstructure of RCAC.The test results indicate that,compared to coral debris,the crushing index of recycled coral aggregate was reduced by 9.4%,while porosity decreased by 33.5%.Furthermore,RCAC retained the early strength characteristics of coral concrete,with compressive strength and flexural strength exhibiting a notable increase as the water-cement ratio decreased.Under identical conditions,the compressive strength and flexural strength of RCAC were 12.7% and 2.5% higher than coral concrete's,respectively,with porosity correspondingly reduced from 3.13% to 5.11%.This enhancement could be attributed to the new mortar filling the recycled coral aggregate.Scanning electron microscopy(SEM)analysis revealed three distinct interface transition zones within RCAC,with the‘new mortar-old mortar’interface identified as the weakest.The above findings provided a reference for the sustainable use of coral concrete in constructing offshore islands.
基金supported by the National Natural Science Foundation of China (Nos. 40973002, 41073002 and 41173049) the Fundamental Research Funds for the Central Universities (No. 020614330005)
文摘The boron isotope paleo-pH proxy has been extensively studied due to its potential for understanding past climate change, and further calibrations were considered for accurate applications of the proxy because of significant variability related to biocarbonate microstructure. In this work, we studied the boron isotopic fractionation between modern marine corals and their coexisting seawater collected along shallow area in Sanya Bay, South China Sea. The apparent partition coefficient of boron（KD） ranged from 0.83×10-3 to 1.69×10-3, which are in good agreement with previous studies. As the analyzed coral skeleton（~5 g） spanned the growth time period of 1–2 years, we discussed the boron isotopic fractionation between pristine corals and modern seawater using the annual mean seawater pH of 8.12 in this sea area. Without taking the vital effect into account,（11B/10B）coral values of all living corals spread over the curves of（11B/10B）borate vs.（11B/10B）sw with the α4-3 values ranging from 0.974 to 0.982. After calibrating the biological effect on the calcifying fluid pH, the field-based calcification on calcifying fluid pH（i.e., Δ（pHbiol-pHsw）） for coral species of Acropora, Pavona, Pocillopora, Faviidae, and others including Proites are 0.42, 0.33, 0.36, 0.19, respectively, and it is necessary to be validated by coral culturing experiment in the future. Correlations in B/Ca vs. Sr/Ca and B/Ca vs. pHbiol approve temperature and calcifying fluid pH influence on skeletal B/Ca. Fundamental understanding of the thermodynamic basis of the boron isotopes in marine carbonates and seawater will strengthen the confidence in the use of paleo-pH proxy as a powerful tool to monitor atmospheric CO2 variations in the past.
基金supported by the "Strategic Priority Research Program" of the Chinese Academy of Sciences (No.XDA05080300)the National Natural Science Foundation of China (No.40830852,41025007,41106054)+1 种基金the National Basic Research Program (973) of China (No.2007CB815905,2010CB950101)the Knowledge Innovation Program of the Chinese Academy of Sciences (No.SQ201009)
文摘Barium to calcium （Ba/Ca） ratio in corals has been considered as a useful geochemical proxy for upwelling,river flood and other oceanic processes.However,recent studies indicated that additional environmental or biological factors can influence the incorporation of Ba into coral skeletons.In this study,Ba/Ca ratios of two Porites corals collected from Daya Bay,northern South China Sea were analyzed.Ba/Ca signals in the two corals were ‘anomalous’ in comparison with Ba behaviors seen in other near-shore corals influenced by upwelling or riverine runoff.Our Ba/Ca profiles displayed similar and remarkable patterns characterized by low and randomly fluctuating background signals periodically interrupted by sharp and large synchronous peaks,clearly indicating an environmental forcing.Further analysis indicated that the Ba/Ca profiles were not correlated with previously claimed environmental factors such as precipitation,coastal upwelling,anthropogenic activities or phytoplankton blooms in other areas.The maxima of Ba/Ca appeared to occur in the period of Sr/Ca maxima,coinciding with the winter minimum temperatures,which suggests that the anomalous high Ba/Ca signals were related to winter-time low sea surface temperature.We speculated that the Ba/Ca peaks in corals of the Daya Bay were most likely the results of enrichment of Ba-rich particles in their skeletons when coral polyps retracted under the stresses of anomalous winter low temperatures.In this case,Ba/Ca ratio in relatively high-latitude corals can be a potential proxy for tracing the low temperature stress.
基金The National Natural Science Foundation of China under contract No.91428203the Guangxi Scientific Projects under contract Nos AD17129063 and AA17204074the Bagui Fellowship from Guangxi of China
文摘The 4.2 ka event that occurred during the period from 4 500–3 900 a BP was characterized by cold and dry climates and resulted in the collapse of civilizations around the world. The cause of this climatic event, however, has been under debate. We collected four corals(Porites lutea) from Yongxing Island, Xisha Islands, South China Sea, dated them with the U-series method, and measured the annual coral growth rates using X-ray technology. The dating results showed that the coral growth ages were from 4 500–3 900 a BP, which coincide well with the period of the4.2 ka event. We then reconstructed annual sea surface temperature anomaly(SSTA) variations based on the coral growth rates. The growth rate-based SSTA results showed that the interdecadal SSTA from 4 500–3 900 a BP was lower than that during modern times(1961–2008 AD). A spectral analysis showed that the SSTA variations from4 500–3 900 a BP were under the influence of El Nino-Southern Oscillation(ENSO) activities. From 4 500–4 100 a BP, the climate exhibited La Nina-like conditions with weak ENSO intensity and relatively stable and lower SSTA amplitudes. From 4 100–3 900 a BP, the climate underwent a complicated period of ENSO variability and showed alternating El Nino-or La Nina-like conditions at interdecadal time scales and large SSTA amplitudes. We speculate that during the early and middle stages of the 4.2 ka event, the cold climate caused by weak ENSO activities largely weakened social productivity. Then, during the end stages of the 4.2 ka event, the repeated fluctuations in the ENSO intensity caused frequent extreme weather events, resulting in the collapse of civilizations worldwide. Thus, the new evidence obtained from our coral records suggests that the 4.2 ka event as well as the related collapse of civilizations were very likely driven by ENSO variability.
基金supported by grantsfrom the National Natural Science Fundation of China(40776085 and 40576052)State Oceanic Administration of China(908-ST-01-08-Coral Reefs Survey)Bureau of Science and Technology for Resources and Environment(YTZJJ0502)
文摘Symbiotic algae （Symbiodinium sp.） in scleractinian corals are important in understanding how coral reefs will respond to global climate change. The present paper reports on the diversity of Symbiodinium sp. in 48 scleractinian coral species from 25 genera and 10 families sampled from the Xisha Islands in the South China Sea, which were identified with the use of restriction fragment length polymorphism （RFLP） of the nuclear ribosomal DNA large subunit gene （rDNA）. The results showed that： （i） Symbiodinium Clade C was the dominant zooxanthellae in scleractinian corals in the Xisha Islands; （ii） Symbiodinium Clade D was found in the corals Montipora aequituberculata, Galaxea fascicularis, and Plerogyra sinuosa; and （iii） both Symbiodinium Clades C and D were found simultaneously in Montipora digitata, Psammocora contigua, and Galaxeafascicularis. A poor capacity for symbiosis polymorphism, as uncovered by RFLP, in the Xisha Islands indicates that the scleractinian corals have low adaptability to environmental changes. Further studies are needed to investigate zooxanthellae diversity using other molecular markers.
基金The National Natural Science Foundation of China under contract No.U1405234the National Basic Research Program(973 Program)of China under contract Nos 2013CB956503 and 2016YFC0302503+1 种基金the Sciences and Technologies Foundation of Guangdong Province of China under contract No.2016A050502038the Sciences and Technologies Foundation of Guangzhou,Guangdong of China under contract No.201508020071
文摘It has been reported that global warming has negative effects on coral ecosystems in the past 50 years and the effects vary in different ocean environment. In order to make clear the coral reef status in the background of global warming along the south coast of Hainan Island of China, satellite and in situ data are used to retrieve the information of the coral reef status and surrounding environmental factors. The results show that cool water induced by upwelling along the south coast of Hainan Island is found in the area every summer month, especially in the relatively strong El Ni？o years（2002–2003 and 2005）. From the NOAA satellite data, degree heating week（DHW） index does not exceed 3 in Sanya Bay even in the relatively strong El Ni？o years. By comparison of a coral reef growth rate in the Sanya Bay with respect to El Ni？o events from 1957 to 2000, coral＇s growth rate is relatively greater during 1972, 1991–1994 and 1998 El Ni？o event. By analyzing the environmental factors, it is found that the cool water induced by upwelling may be the main reason for protecting corals from global warming effects.
基金the Science&Technology Basic Resources Investigation Program of China(No.2017FY100804)the National Natural Science Foundation of China(No.41930533)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB42000000)the Senior User Project of R/V Kexue。
文摘Three deep-sea black corals belonging to the family Schizopathidae,are reported from two seamounts on the Caroline Ridge in the tropical Western Pacific:Umbellapathes parva sp.nov.with depth of 1488-1766 m,Telopathes cf.magna MacIsaac&Best,2013 with depth of 937-1016 m,and Stauropathes cf.punctata(Roule,1905)with depth of 942-1353 m.The latter two species are the first records in the Western Pacific Ocean.U.parva sp.nov.is characterized by monopodial corallum,relatively long unpinnulated stalk with complex pinnulated branche s developing from the lowermost primary pinnules and small spine s.It differs from two known congeners by much smaller spine s and the present of secondary pinnules.T.cf.magna MacIsaac&Best,2013 has sparsely branched corallum,relatively long and simple pinnules arranged in subopposite or alternate pairs.S.cf.punctata(Roule,1905)is characterized by the corallum with almost planar pinnulated branches,and pinnules arranged in subopposite pairs.Our results indicate that the corallum size and shape are variable in conspecific specimens particularly those at different growth stages.By contrast,the size of the polypar spines as well as the abpolypar spines have little variation and can be served as a main differing feature for schizopathid species.The phylogenetic analyses using nuclear internal transcribed spacer region(spanning partial 18 S rDNA,ITS 1,5.8 S,ITS2,and partial 28 S rDNA)and two mitochondrial fragments cox3-IGR-coxl(COI)and trnW-IGR-nad2(NAD2)showed Telopathes,Stau ropathes,and Bathypathes had close relationships,and Umbellapathes formed a sister clade with Alternatipathes.
文摘The author traced the history of the thirty years of study of the Vietnamese reefs since the second half of the 20th century up to the present time. This paper describes the types of reefs, taxonomic composition and structure of Scleractinian reef ecosystems. It is shown that due to a high level of diverse knowledge revealed, high species richness of coral fauna of Vietnam (376 species of 80 genera) is a single point of origin coral fauna Indo-Pacific. Analysis of knowledge of Vietnamese corals and reefs revealed the extent of their positive or negative status under anthropogenic influence or under the level of wilderness protection, experiment on artificial cultivation of corals and the re-establishment of a coral community.
基金funded by the Indonesian Institute of Sciences(LIPI)through the DIPA 2021 Research Fund B-10405/IPH/HK.01.03/XI/2020。
文摘Soft corals are well-known as excellent sources of marine-derived natural products.Among them,members of the genera Sar-cophyton,Sinularia,and Lobophytum are especially attractive targets for marine natural product research.In this review,we reported the marine-derived natural products called cembranoids isolated from soft corals,including the genera Sarcophyton,Sinularia,and Lobophytum.Here,we reviewed 72 reports published between 2016 and 2020,comprising 360 compounds,of which 260 are new compounds and 100 are previously known compounds with newly recognized activities.The novelty of the organic molecules and their relevant biological activities,delivered by the year of publication,are presented.Among the genera presented in this report,Sarcophyton spp.produce the most cembranoid diterpenes;thus,they are considered as the most important soft corals for marine natural product research.Cembranoids display diverse biological activities,includ-ing anti-cancer,anti-bacterial,and anti-inflammatory.As cembranoids have been credited with a broad range of biological activities,they present a huge potential for the development of various drugs with potential health and ecological benefits.
文摘Coral samples collected from the waters off the Leizhou Peninsula, the Hainan Island and the Yongxing Island of the Xisha Islands were analyzed by thermal ionization mass spectrometry (TIMS) and multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) for their U-Th systematics. Their uranium contents are mostly lower than 3μg/g, and the δ+{234}U(T) values are within the range of 150±5. X-ray diffraction analysis showed that the corals are all composed of aragonite. This demonstrates that the corals determined have maintained a close system for 7000 years and their skeletons bear much information about the primitive tropical marine environment. The highly precise age sequence of the corals determined has revealed that there occurred three phases of high sea level in the South China Sea waters, which are dated at 6799-6307 a B.P., 4472-4285 a B.P. and 1279-1012 a B.P., respectively. The three phases lasted 492 a, 187 a and 267 a, respectively. These three phases of high sea level are corresponding to the warm environments that had appeared in China during the Megathermal Period and the Medieval Warm Period in the past ten thousand years.
文摘The existing hermatypic coral community is composed of localities in different successional ages.Data sets were selected from original sampling data to deduce the trajectory of community structure in this and subsequent papers.Patterns of species composition and abundance distribution during community succession in the scope of different habitats were described in this paper.It is found that the effect of succession on community structure is closely correlated with the environmental conditions.Each coral assemblage in different habitat has its own distinguishing temporal pattern of species composition and abundance distribution.
文摘The paper analyzes both published and unpublished results of the investigations of Vietnamese reef building corals and reefs performed in the last decades of the twentieth century and first decades twenty-first. The state of the art in the study of reef-building scleractinian corals and reefs is presented. The scleractinian fauna of Vietnam is shown to match in species diversity (350 species of 80 genera) the tropical coral fauna of the Indonesian–Malacca fertile center, from which Indo-Pacific reef-building corals originated. The whole Vietnam coast from the Gulf of Tonkin to the Gulf of Siam is a biogeographically single whole and is a part of the Indo-Polynesian Province of the Indo-Pacific Area.
基金Science and Technology Development Fund(FDCT) of Macao SAR (FDCT / 017 / 2015 / AMJFDCT134/2014/A3).
文摘OBJECTIVE To identify and characterize a novel neuroprotective ShK peptide and its analogue originated from coral P.caribaeoru.METHODS P.caribaeoru was collected and subjected to transcriptome sequencing at which further bioinformatics analysis had identified a unigene encoding a putative ShK protein candidate,named as PcShK1.PcShK1 and its rhodamine derivative(PcShK1-RhoB) were synthesized and tested for the neuroprotective effect in 6-OHDA induced Parkinson disease models in vitro and in vivo.Briefly,zebrafish larvae were co-exposed to 6-OHDA and various doses of the peptides;then,dopaminergic(DA) neurons immunoreactivity and locomotion behavior of the zebrafish larvae were examined.Similarly,PC12 cells were cultured with 6-OHDA in the absence or presence of different concentrations of peptides.Cell viability was determined by MTT assay while calcium flow in the PC12 cells was monitored by Fluo-4 fluorescent dye.RESULTS Compared with control group,6-OHDA treatment could lead to DA neurons loss and locomotion deficits in PD model of zebrafish larvae(P<0.01).Both PcS hK 1(2.5,5.0 and 7.5 μmol·L^(-1)) and PcS hK 1-RhoB(0.50 and 0.75 μmol·L^(-1)) were found to protect and restore dopaminergic neurons from6-OHDA mediated injury and locomotion deficiency in the PD zebrafish respectively(P<0.01).In addition,PcShK1(2.5 to 20.0 μmol·L^(-1)) and PcShK1-RhoB(0.6 to 2.5 μmol·L^(-1)) effectively prevented against 6-OHDA toxicity in PC12 cells(P<0.01).Further study revealed that they might exert their neuroprotective effects through regulating the calcium homeostasis.CONCLUSION PcS hK 1 and PcS hK 1-RhoB show neuroprotective effects on 6-OHDA induced PD models,and the underlying protective mechanisms of these peptides probably involve calcium homeostasis regulation.
基金supported by the National Natural Science Foundation of China (Grant No.: 41472030)the Ministry of Science and Technology of the People’s Republic of China (Grant No.: 2015FY310100)the China Geological Survey (Grant Nos.: DD20160120-04,DD20160345,12120114026701,and DD20160201)
文摘Scleractinian corals appeared during the Anisian period of the Triassic after the end-Permian mass extinction, which in Triassic were distinct from the Jurassic-Cretaceous scleractinian corals. The study on Triassic scleractinian coral fauna as a separate field is significant for exploring the development and evolution of modern corals and investigating environmental changes since the Mesozoic. The first Triassic coral in China was reported in 1925, and since then, nearly 25 articles dealing with taxonomy and 17 papers about fossil reports on Triassic scleractinian corals in China have been published, which refer to 60 genera and 312 species, 49 localities and 25 strata. In this paper, the history, taxonomy, localities, stratigraphic distribution, current research, and existing knowledge gaps of the Triassic scleractinian corals in China are reviewed. More specifically, the research findings of the Triassic scleractinain coral in China since 1925 are discussed; the species of the Triassic scleractian coral fossil reported in China, has been examined and its synonyms have been sorted out; the geographical distributions of the Middle and Late Triassic scleractinian corals in China are systematically treated; the Triassic coral biostratigraphy in China has been improved; and the stratigraphic ranges of existing genera and species are provided. The above conclusions are presented in the form of complete figures. At the same time, we analyzed shortcomings in current research and identified productive future research directions of the Triassic scleractinian corals in China.
文摘The end-Triassic （also Triassic-Jurassic） mass extinction severely affected life on planet Earth 200 million years ago. Paleoclimate change triggered by the volcanic eruptions of the Central Atlantic Magmatic Province （CAMP） caused a great loss of marine biodiversity, among which 96% coral genera were get lost. However, there is precious little detail on the paleoecology and growth forms lost between the latest Triassic extinction and the Early Jurassic recovery. Here a new pilot study was conducted by analyzing corallite integration levels among corals from the latest Triassic and Early Jurassic times. Integration levels in corals from the Late Triassic and Early Jurassic were determined through both the Paleobiology Database as well as from a comprehensive museum collection of fossil corals. Results suggest that in addition to a major loss of diversity following the end-Triassic mass extinction, there also was a significant loss of highly integrated corals as clearly evidenced by the coral data from the Early Jurassic. This confirms our hypothesis of paleoecological selectivity for corals following the end-Triassic mass extinction. This study highlights the importance of assigning sim- ple to advanced paleoecological characters with integration levels, which opens a useful approach to understanding of mass extinction and the dynamics of the recovery.
