- JIANG Zenghao;CHEN Xu;MENG Jing;CAO Anzhou;
Ocean mixing is a consequence of essential dynamic processes such as internal tides and lee waves that occur near the seafloor topography. Internal tides and lee waves are generated by barotropic tidal currents and geostrophic flows, respectively.Ocean current is composed of multiple flows; thus, internal tides and lee waves occur concurrently in the real ocean. In this paper, the Massachusetts Institute of Technology general circulation model(MITgcm) is used to conduct 2D numerical experiments. By varying background flow intensities, the energy and dissipation relationship between internal tides and lee waves are investigated. The results reveal that the internal tide beams become asymmetric due to the influence of Doppler shift. The lee wave structure gradually leads the wave field when the background flow velocity rises constantly. The presence of a background flow increases the energy portion of the high-mode wave by up to 15% – 20%. Moreover, strong shear, owing to the background flow, considerably increases dissipation. When the background flow velocity is higher than the barotropic tidal current velocity, the isopycnal overturn triggered by the lee wave generates a dissipation of the same order of magnitude as the shear.
2025年02期 v.24 259-268页 [查看摘要][在线阅读][下载 1303K] - SHI Hongyuan;SUN Yongkang;SUN Jiwei;LI Longsheng;ZHAO Shengnian;HONG Xin;LI Qingjie;WANG Haixia;YUAN Xiaofan;
To investigate the effect of typhoon path translation on storm surge augmentation, the storm surge during Typhoon 1909 Lekima in the East China Sea is simulated using Delft 3D. The model sets up three scenarios to analyze the path's effect on storm surge in the Shandong Peninsula Sea by shifting the typhoon path to the east and west. Results show that the areas of maximum storm surge in each scenario are located on both sides of the typhoon path and shift along with its movement. When the typhoon path shifts eastward, the maximum storm surge intensifies at Zhifu Island station 8 hours earlier. Conversely, a westward shift in the typhoon track leads to a maximum storm surge increase at Shidao Island station 12 hours earlier. Other scenarios exhibit minimal deviation from the original route. Typhoons penetrating deep inland can induce substantial storm surges, with the most extensive surge area situated in the western part of the Shandong Peninsula.
2025年02期 v.24 269-280页 [查看摘要][在线阅读][下载 970K] - ZHU Qichao;HUANG Chuanjiang;XIA Yuzhuo;YANG Ying;GUO Jingsong;XIA Changshui;QIAO Fangli;
The heat transfer coefficient of the water surface is an important parameter in the design of thermal discharge in nuclear power plant engineering.In this study,in situ observations were performed in the northwestern South China Sea near a coastal nuclear power plant to evaluate the applicability of heat transfer coefficient calculation algorithms commonly used in marine thermal discharge engineering in China.The results show that the Regulation for Hydraulic and Thermal Model in Cooling Water Projects (SL 160-2012)is not applicable in calculating the heat transfer coefficient in offshore areas.SL 160-2012 significantly overestimates the heat loss at the sea surface.However,Code for Design of Cooling for Industrial Recirculating Water (GB/T 50102-2014) performs well,and its estimation coefficient is roughly consistent with the estimations of the COARE 3.6 bulk algorithm,which is extensively used in physical oceanography for calculating air-sea heat fluxes,and the Gunneberg formula.In a 3-day observation,the average heat transfer coefficients estimated using these three algorithms were 50.4,48.5,and 48.8 W m~(-2)℃~(-1),respectively,with a deviation of less than 4%among them,whereas that estimated using SL 160-2012 was as high as 176.3 W m~(-2)℃~(-1).The abnormally large value of SL 160-2012 is due to its additional cooling term,which is artificially increased by 100 times because of the incorrect unit conversion used when developing the regulation.If this error is corrected,the value will decrease to 50.5 W m~(-2)℃~(-1),which is very close to the estimation of GB/T 50102-2014.
2025年02期 v.24 281-288页 [查看摘要][在线阅读][下载 1022K] - WANG Yuhan;DONG Sheng;
The interaction between regular waves and an oscillating wave energy converter(WEC) in front of a vertical seawall is investigated using a 2D analytical model. A three-degree of freedom(DOF) WEC and a WEC hinged to the seawall(constrained to pitch mode) are considered to examine the influence of the DOF of the WEC on the wave energy extraction performance. Results show that the piston-mode water resonance in the gap and the coupled WEC and water column resonant motion significantly influence the wave energy extraction efficiency. At low frequency, the case with a 3-DOF WEC has a broader high-efficiency bandwidth than that with a heaving WEC. However, 3-DOF WEC exhibits worse performance at high frequencies. The frequency response of the wave energy capture width ratio(CWR) for the pitching WEC case shows a trimodal trend under the specified conditions. It showcases the best overall wave energy extraction performance in terms of the high-efficiency bandwidth. Furthermore, a parametric study indicates that the gap distance between the WEC and the seawall has tremendous effects on the CWR of both cases. As the position of the hinge point of the pitching WEC changes, the CWR at the low and high frequencies shows opposite trends.
2025年02期 v.24 289-302页 [查看摘要][在线阅读][下载 1390K] - ZHANG Puyang;LI Jingyi;BAI Yu;LE Conghuan;DING Hongyan;
For the development of an integrated rounded rectangular wellhead platform with a bucket foundation, a model test was conducted to study the towing motion response of such a structure under still water and wave conditions. The influence of various factors on the floating stability of the structure was investigated through alterations of the towing conditions(draft, towing point position, and wave conditions), and the related influencing mechanism was analyzed. Comparison and analysis were performed to determine the changes in the structure motion pattern and various effects of towing conditions on the structure during towing in still water and regular waves. Moreover, the influence of each factor on the structure's motion response during towing was analyzed using the Apriori algorithm. In addition, for the simulation of the towing process under actual sea conditions, a towing test was performed under irregular waves, and the stability of towing in irregular waves was compared with that in regular waves.
2025年02期 v.24 303-322页 [查看摘要][在线阅读][下载 3523K] - WANG Qing;ZHAN Chao;SU Teng;SHI Hongyuan;WANG Longsheng;ZENG Lin;LIU Xianbin;CUI Buli;
The historical movements of relative sea level(RSL) reflect the geomorphological dynamics around coastal regions in the past, and reconstructing the RSL curve contributes to the prediction of future RSL movements. On the basis of the sediment sequence and optical stimulated luminescence(OSL) dating data of three boreholes in the Yellow River Delta(YRD), the positions of paleo-coastlines and the movements of RSL in the last 2000 years were reconstructed. The main results are as follows: 1) the YRD coast transformed from a tide-dominated silty coast to a wave-dominated sandy coast and back to a tide-dominated silty coast in the last 2000 years. 2) The sand layers consisting of shell fragments indicated the locations of the coastline in 1855 AD, 893 AD, and 40BC, and their top elevations were close to the mean high water level in the corresponding years. 3) The mean sea level elevation in 79 BC, 1019 AD, and 1800 AD relative to the modern sea level was-4.52,-4.52, and-2.92 m, respectively. 4) The RSL was almost stagnant during 79 BC – 1019 AD, rose slowly during 1019 – 1800 AD due to the reverse change of global climate from the Little Ice Age to the Medieval Warm Period, and rose significantly after 1800 AD due to the warm period. 5) The movement of RSL controlled the surface slope of YRD, which was a slope of approximately 0.022‰ at 893 AD, an inverted slope of 0.144‰ at 1855 AD, and a slope of 0.075‰ recently. These findings indicate that the modern YRD is far from being abandoned in the future, providing a historical geomorphological basis for the management of the Yellow River Estuary.
2025年02期 v.24 323-331页 [查看摘要][在线阅读][下载 940K] - WANG Chenjuan;LI Yuguo;LU Jie;DAI Tianyi;ZHONG Zhihao;LIU Lanjun;CHEN Jialin;
A new Ag/AgCl sensor for measuring marine electric fields was prepared and characterized through electrochemical methods and scanning electron microscopy. Its performance was evaluated in both laboratory and deep-water settings. The study indicates that the double-pulse electrodeposition method is advantageous for producing Ag/AgCl sensors that maintain excellent stability over time. During a 20-day continuous stability test, the potential difference of the sensor consistently remained between-24.76 μV and 62.07 μV, with a minimum potential difference drift of 2.77 μV per 24 h. All sensors accurately detected artificial signals in both the time and frequency domains, and their responses were consistent with one another. The minimum noise level of the sensor was 0.59n V( ■)~(-1)@1 Hz. The sensor performed well in high-precision electric field measurements at a depth of approximately 2800 m in the South China Sea. The high stability and low noise level of the sensor make it an effective tool for detecting electrical conductivity structures beneath the seafloor.
2025年02期 v.24 332-342页 [查看摘要][在线阅读][下载 1123K] - SUI Yanming;ZHANG Yingying;CHEN Shihao;SHI Yangyang;ZOU Jiaxin;MOHAMED Mohsen;QIN Kunyun;YU Yebing;LIU Zhiquan;ZHENG Liang;LV Linlan;
Microplastic(MP) pollution has spread from the mainland to the ocean. However, Haizhou Bay, which is one of the important land-ocean transition zones, has been reported relatively little about the enrichment of MPs. To provide fundamental data for MP pollution in Haizhou Bay, we studied the occurrence of microplastics in the intestines of 8 species of fish with different habits and feeding modes. The fish intestines were digested with a 10% KOH solution, and MPs are separated with a glass fiber filter. Then, the size,shape, color, and composition of the MPs were analyzed using a stereomicroscope and Fourier transform infrared spectrometer. The results showed the abundance of MP intake ranged from 0.02 items g~(-1) to 0.16 items g~(-1) and the detection rate of MPs ranged from 53.33% to 80% across different fish species. The MP intake in benthic fish and omnivorous fish was significantly higher than that of pelagic fish and predatory fish. Smaller MPs(< 0.25 mm) were the dominant types and accounted for 62.50% of the total. The fiber was the prevailing shape of MPs, and the black MPs were the most common, followed by red and yellow ones. Polyethylene terephthalate(PET), polyamide(PA), and polystyrene(PS) were the main components of MPs, accounting for 34.9%, 29.9%, and 16.4%, respectively.According to the composition analysis of MPs, the main sources of MPs in fish of Haizhou Bay were attributed to marine aquaculture and port construction. The results are helpful for our better understanding of the status of MP pollution in this area, and further aid in the development of the pointed measures to mitigate and prevent the MP pollution in this ecologically important area.
2025年02期 v.24 343-354页 [查看摘要][在线阅读][下载 874K] - WANG Shiyu;TONG Siyou;WANG Jingang;WEI Hao;HENG Shuaijia;XU Xiugang;YANG Dekuan;ZHANG Xu;WANG Shurong;LI Yuxing;
The use of blended acquisition technology in marine seismic exploration has the advantages of high acquisition efficiency and low exploration costs. However, during acquisition, the primary source may be disturbed by adjacent sources, resulting in blended noise that can adversely affect data processing and interpretation. Therefore, the de-blending method is needed to suppress blended noise and improve the quality of subsequent processing. Conventional de-blending methods, such as denoising and inversion methods,encounter challenges in parameter selection and entail high computational costs. In contrast, deep learning-based de-blending methods demonstrate reduced reliance on manual intervention and provide rapid calculation speeds post-training. In this study, we propose a Uformer network using a nonoverlapping window multihead attention mechanism designed for de-blending blended data in the common shot domain. We add the depthwise convolution to the feedforward network to improve Uformer's ability to capture local context information. The loss function comprises SSIM and L_1 loss. Our test results indicate that the Uformer outperforms convolutional neural networks and traditional denoising methods across various evaluation metrics, thus highlighting the effectiveness and advantages of Uformer in de-blending blended data.
2025年02期 v.24 355-364页 [查看摘要][在线阅读][下载 1366K] - DAI Zili;LAN Baisen;JIANG Mingtao;JIANG Shenghui;
Submarine landslides frequently occur on continental margins and slopes, thereby causing serious damage to offshore structures. Therefore, analyzing their motion behavior and predicting their impact forces are crucial. In this work, the smooth particle hydrodynamics(SPH) algorithm is used in the development of a multiphase flow model for submarine landslides. The underwater landslide and the ambient water are simulated using the non-Newtonian and Newtonian fluid models, respectively. An artificial diffusion term of density is incorporated in the governing equation, and the equation of state is modified to improve the stability and accuracy of the SPH model. Three benchmark problems are simulated using the SPH model. The effect of SPH particle size on the simulated results is also explored. The effects of the rheological parameters on the landslide motion behavior are investigated by conducting a sensitivity analysis. Numerical results fit the experimental data well, indicating the good stability of the SPH model and its accuracy in simulating the motion and impact behavior of submarine landslides.
2025年02期 v.24 365-376页 [查看摘要][在线阅读][下载 1076K] - SONG Jian;HUANG Meng;LI Xiang;ZHANG Zhenqiang;WANG Chunxiao;ZHAO Zhigang;
Accurate wind speed measurements on maritime vessels are crucial for weather forecasting, sea state prediction, and safe navigation. However, vessel motion and challenging environmental conditions often affect measurement precision. To address this issue,this study proposes an innovative framework for correcting and predicting shipborne wind speed. By integrating a main network with a momentum updating network, the proposed framework effectively extracts features from the time and frequency domains, thereby allowing for precise adjustments and predictions of shipborne wind speed data. Validation using real sensor data collected at the Qingdao Oceanographic Institute demonstrates that the proposed method outperforms existing approaches in single-and multi-step predictions compared to existing methods, achieving higher accuracy in wind speed forecasting. The proposed innovative approach offers a promising direction for future validation in more realistic maritime onboard scenarios.
2025年02期 v.24 377-386页 [查看摘要][在线阅读][下载 1075K] - ZHU Chenghao;YU Peng;GUO Zixian;WANG Qigang;LIU Hongjun;
The traditional cement-based stabilization cannot effectively stabilize the marine soft clay under submerged conditions.In order to solve this problem, the enhancement of cement-stabilized marine soft clay was investigated in this study by adding the ionic soil stabilizer(ISS) and polyacrylamide(PAM). For this purpose, varying contents of ISS and PAM(ISS-P) were added into cement-stabilized marine soft clay and subjected to curing under submerged conditions. Atterberg limits tests, direct shear tests, unconfined compression strength(UCS) tests, water-stability tests, scanning electron microscopy analysis, and X-ray diffraction analysis were carried out. The results show that using 1.8% ISS and 0.9% PAM as the optimal ratio, the cohesion, internal friction angle,UCS, and water-stability of the samples increased by 182.7%, 15.4%, 176.5%, and 368.5% compared to the cement-stabilized soft clay after 28 d. The increment in soil cohesion with increasing ISS-P content was more apparent than that in the internal friction angle.The combined action of ion exchange attraction and electrostatic adsorption altered the failure characteristics of the samples, resulting in localized micro-cracking and multiple failure paths. Increasing the content of ISS-P strengthened the skeletal structure of soil,reduced inter-particle spacing, and enhanced the water-stability. Additionally, ISS promotes the hydration of cement and compensates for the inhibitory effect of PAM on early cement hydration. ISS-P can effectively enhance the strength and stability of submerged cement-based stabilized marine soft clay.
2025年02期 v.24 387-403页 [查看摘要][在线阅读][下载 2332K]
- WANG Bowen;CAO Xiyu;REN Wenhao;ZHAO Chunyan;LI Qing;FAN Ruiyong;MEN Xianhui;ZHOU Yangen;REN Yichao;
Atlantic salmon(Salmo salar) represents the primary species in aquaculture. The gut microbiota plays a crucial role in nutrient processing and protection against pathogenic bacteria. Nonetheless, the composition and functionality of the gut microbiota in Salmo salar at different growth stages remain largely unexplored. This study investigated the alterations within the gut microbial communities and their associated metabolites across different growth stages of Salmo salar, specifically when the body weights were 1.0kg(S1 group), 2.0 kg(S2 group), 4.0 kg(S3 group), and 6.0 kg(S4 group), using microbiome sequencing and liquid chromatographymass spectrometry(LC-MS) technology. Results indicated significant changes in the gut microbiota and metabolite profiles concurrent with fish growth. Notably, the abundance of Firmicutes decreased, and Proteobacteria increased, resulting in a decreased Firmicutes/Bacteroidetes(F/B) ratio. Concurrently, the abundance of potential pathogenic bacteria such as Stenotrophomonas, Vibrio,Aeromonas, Staphylococcaceae, Enterobacteriaceae, Enterococcaceae, and Haemophilus increased, whereas beneficial bacteria like Lactobacillus and Bacilli decreased. The gut microbiota in the S1 group exhibited an increase in the abundance of beneficial bacteria.Conversely, in the S2, S3, and S4 groups, the prevalence of pathogenic bacteria increased. Metabolic profiling revealed significant upregulation of arachidonic acid(ARA) and taurine in the S2 and S3 groups, while citric acid, riboflavin, and pantothenic acid notably increased in the S4 group. Particularly, several amino acids such as threonine, lysine, and serine in the gut microbiota metabolites were significantly reduced in the S2, S3, and S4 groups, correlating positively with the respective essential amino acid concentrations in muscle tissue. The S1 group exhibited a more active gut microbiota associated with amino acid metabolism, resulting in higher muscle amino acid content. This study identified gut microbiota and its metabolic products at different growth stages of Salmo salar,providing a scientific basis for proactive intervention of gut microbiota and improve the quality of aquatic products.
2025年02期 v.24 404-416页 [查看摘要][在线阅读][下载 2281K] - WENG Zhaohong;XIE Yangjie;FANG Qi;LI Jun;LIU Jingwen;WANG Jiaqiao;HUANG Liangmin;QU Tao;XIE Wenliang;
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.
2025年02期 v.24 417-426页 [查看摘要][在线阅读][下载 625K] - YANG Rutao;HUANG Zurui;LI Jinku;WEN Haishen;QI Xin;ZHANG Kaiqiang;ZHANG Jingru;LIU Mengqun;LI Jifang;ZHANG Meizhao;LI Yun;
Urea is a major end product of nitrogen catabolism, serving as an osmolyte to regulate osmotic stress in fish exposed to varying water environments. It has been well known that urea transporters (UTs) facilitate the rapid movement of urea across cell membranes. However, researches on ut genes were predominantly focused on elasmobranchs and early developmental stages of fish.In this investigation, a total of three ut genes were identified in spotted sea bass. Phylogenetic, homology, and syntenic analyses were conducted to validate the annotation and assess the evolutionary relationships among ut genes. Both ut-a and ut-b genes have retained their evolutionary stability, demonstrating a significant level of homology between them. To gain deeper insights into the evolution of ut genes in spotted sea bass, we performed selective pressure analysis using site, branch, and branch-site models. The results suggested that positive selection likely played a significant role in shaping the evolution of the ut gene family. Furthermore, tissue-specific expression analyses revealed high expression levels of ut genes in osmoregulatory tissues such as the gill and kidney. Additionally,all three ut genes exhibited salinity-related expression patterns in gill and kidney tissues during both seawater-to-freshwater (SF) and freshwater-to-seawater (FS) adaptation. In situ hybridization results demonstrated the localization of both ut-a and ut-c mRNAs on the gill lamellae and adjacent gill filament epithelium. In summary, our study establishes a solid foundation for future research elucidating the evolutionary relationships and functional significance of ut genes during salinity acclimation in spotted sea bass and other teleost species.
2025年02期 v.24 427-438页 [查看摘要][在线阅读][下载 1137K] - XUAN Wendan;ZHU Wenbin;ZHANG Haobo;WU Tian;ZHU Kai;LI Pengfei;ZHAO Yixiang;
The red tilefish Branchiostegus japonicus is an economically important demersal fish species with high-quality. However, research on its reproductive biology and population structure characteristics is limited. To better understand the reproductive biological features of B. japonicus, a study was conducted on 461 individuals collected from the East China Sea(27?00' – 31?00'N,122?30'– 127?30'E) from March to December in 2021. This study analyzed the relationship between standard length and the body weight, and detected the sex ratio, length at first sexual maturity, reproductive period, fecundity, and spawning type of this species.The results revealed a power function relationship between body weight(W) and standard length(L) in the samples as the following regression equation: W = 0.000014 L~(3.16)(R~2 = 0.956). The sex ratio was close to 1:1(χ~2 = 1.11, P > 0.05), and the sex ratio exhibited significant differences according to different standard lengths. Using the logistic equation, we estimated that 50% of B. japonicus individuals had a standard length at sexual maturity of L_(50) = 210 mm. By analyzing the monthly variation in the gonadal index and the proportion of each stage of ovarian development in each month, we assumed that the spawning period of B. japonicus occurred from May to November, and the peak spawning period occurred from June to October. The absolute fecundity was 51441 ± 33232 eggs, the relative fecundity at the standard length was(210 ± 117) eggs mm~(–1), and the relative fecundity relative to body weight was(184 ± 89)eggs g~(–1). The distribution of the egg diameter of B. japonicus had only one obvious peak, indicating the spawning pattern of B. japonicus was once a year. This study updated and enriched the basic biological data of B. japonicus, which is beneficial for obtaining a better understanding of its population dynamics, and promoting the conservation and sustainable utilization of B. japonicus in East China Sea.
2025年02期 v.24 439-447页 [查看摘要][在线阅读][下载 685K] - MING Jiagen;SU Dongyan;HAN Xiufeng;WU Xiangyang;LI Bo;TAN Jiabo;SONG Xiaojun;
The Chinese seabass(Lateolabrax maculatus) is one of the most popular and valuable aquaculture species in China. Recently, the disease caused by Vibrio anguillarum has brought huge economic losses in the L. maculatus industry. However, the immune response of L. maculatus after V. anguillarum infection remains unknown. In this study, the blood homeostasis, gut microbiota and transcriptomic profiling of L. maculatus after V. anguillarum infection were investigated. Our results indicated that the levels of superoxide dismutase(SOD), alanine aminotransferase(ALT) and total bilirubin(TBIL) increased, while the levels of blood glucose(BG),total protein(TP) and albumin(ALB) decreased after V. anguillarum infection. The analysis of the gut microbiota composition revealed that the dominant phyla was Firmicutes and Proteobacteria, and the relative abundance of genus Vibrio increased after V. anguillarum infection. Subsequently, the differentially expressed genes(DEGs) in the kidney and spleen after V. anguillarum infection were analyzed by transcriptome sequencing. The results indicated that immunity-related genes like TLR5, TLR8, TLR9, IL-1β, CCL3, IFNγ,CXCL11 and TNFα were affected and the NOD-like receptor signaling pathway, cytokine-cytokine receptor interaction and Toll-like receptor signaling were activated. Thus, an effective immune and pro-flammatory response can help resist V. anguillarum infection.Our results provide a theoretical support for improving the disease resistance ability of L. maculatus.
2025年02期 v.24 448-462页 [查看摘要][在线阅读][下载 2159K] - BAI Xianchao;LIANG Yuanxin;CHENG Geng;WANG Ziheng;XU Chengxun;LI Qi;
Crassostrea gigas is distinguished by its robust fertility, adaptability to various environmental conditions, and rich nutritional profile, which render it a cornerstone of the global shellfish market. Tetraploid oysters, in particular, is a pivotal role within the oyster industry, however, their growth and survival characteristics need to be improved. This study aimed to assess the viability of enhancing the growth and survival characteristics of tetraploid C. gigas through genetic selection. This was achieved by investigating the heritability and genetic correlation of growth and survival at various stages of C. gigas development. Genetic parameters were assessed based on in-group correlations in 28 full-sib families during the larval stage(days 3, 8, 13, 18, and 23 after fertilization). The heritability of larval shell height and shell length ranged from 0.50 to 0.71 and 0.44 to 0.71, respectively, and varied with age. The heritability of larval survival was 0.40 – 0.64, indicating that it is viable to enhancelarval survival through selection. The genetic correlation between the growth traits of larvae at different ages was highly positive(0.959 – 0.999), indicating that the selection of a single growth trait could cause the positive response of other growth traits. However, the genetic correlation between larval survival and growth traits was low, showing a significant negative correlation(-0.198 –-0.293) at day 23 of age, suggesting thatselecting for enhanced survival in tetraploid C. gigas may result in a detrimental impact on growth traits.The results are helpful for future researches to evaluate the genetic parameters related to growth and survival traits in juvenile and adult stages of the tetraploid family of C. gigas,which can provide further guidance for the selection of tetraploid C. gigas.
2025年02期 v.24 463-470页 [查看摘要][在线阅读][下载 608K] - XU Tianheng;ZHANG Chongliang;XU Binduo;XUE Ying;JI Yupeng;REN Yiping;
Species distribution patterns is one of the important topics in ecology and biological conservation. Although species distribution models have been intensively used in the research, the effects of spatial associations and spatial dependence have been rarely taken into account in the modeling processes. Recently, Joint Species Distribution Models(JSDMs) offer the opportunity to consider both environmental factors and interspecific relationships as well as the role of spatial structures. This study uses the HMSC(Hierarchical Modelling of Species Communities) framework to model the multispecies distribution of a marine fish assemblage, in which spatial associations and spatial dependence is deliberately accounted for. Three HMSC models were implemented with different structures of random effects to address the existence of spatial associations and spatial dependence, and the predictive performances at different levels of sample sizes were analyzed in the assessment. The results showed that the models with random effects could account for a larger proportion of explainable variance(32.8%), and particularly the spatial random effect model provided the best predictive performances(R_(mean)~2=0.31), indicating that spatial random effects could substantially influence the results of the joint species distribution. Increasing sample size had a strong effect(R_(mean)~2=0.24–0.31) on the predictive accuracy of the spatially-structured model than on the other models, suggesting that optimal model selection should be dependent on sample size. This study highlights the importance of incorporating spatial random effects for JSDM predictions and suggests that the choice of model structures should consider the data quality across species.
2025年02期 v.24 471-482页 [查看摘要][在线阅读][下载 1057K] - NIDA Imtiaz;JIN Runze;LI Yongliang;WU Qingyang;MU Changkao;WANG Chunlin;LI Ronghua;
This study examined four species of Scylla genus(S. paramamosain, S. olivacea, S. serrata, and S. tranquebarica) morphologically and molecularly. Morphologically, distinct frontal lobe spine shapes and colorations were observed. Using HRM genotyping with CSN9 primers, we identified clear species-specific melting curve distinctions. The Tm values of S. serrata, S. paramamosain, S.tranquebarica and S. olivacea are 79.55℃, 80.12℃, 78.12℃ and 82.04℃, respectively. Sequencing data validated these results, revealing 28 SNPs and 9 haplotypes. Amino acid analysis showed arginine dominance in S. paramamosain, which was 40.64 mg g~(-1), and a TFAA range of 135.70 – 149.65 mg g~(-1). A total of 26 fatty acids were identified, while S. paramamosain showed the highest concentration(P < 0.05). EPA was a major component(16.17% – 23.26%), while S. paramamosain exhibited the highest levels. Principal component analysis and cluster analysis highlighted distinct species groupings based on amino acid and fatty acid profiles. These findings provide comprehensive insights into Scylla species' morphological, molecular, and biochemical diversities.
2025年02期 v.24 483-494页 [查看摘要][在线阅读][下载 869K] - ZHANG Luyao;HE Zhichao;SUN Yan;LI Jian;CHENG Pengfei;AGATHOS Nicolas Spiros;ZHOU Chengxu;ZHANG Lin;HAN Jichang;
Coccolithophores have unique ability of dual carbon fixation(photosynthesis and biocalcification) and can accumulate bioactive compounds effectively, thereby showing huge potential for CO_2 bioremediation and simultaneous production of valueadded substances. However, biotechnological exploration of these microalgae is still very limited. In order to develop efficient cultivation strategies of these organisms, we tested the abilities of Chrysotila roscoffensis, a coccolithophore, to grow under mixotrophic and heterotrophic cultivation conditions. It was confirmed that only glycerol stimulated the cell growth of this microalga in the presence of light. To study the physiological significance of mixotrophy, we conducted cell culture experiments both autotrophically and mixotrophically, the only difference of which was optimal amount of glycerol was added under mixotrophic conditions. The results showed that the addition of glycerol substantially enhanced the lipids and monounsaturated fatty acids accumulation of C. roscoffensis, but imposed slight influences on the photosynthetic capacity, pigments content, polyunsaturated fatty acids content, and biocalcification. We concluded that mixotrophy might be an appropriate strategy for exploration of this species for production of high value molecules.
2025年02期 v.24 495-505页 [查看摘要][在线阅读][下载 618K] - JANUAR Hedi Indra;HIDAYAH Izhamil;SUTOMO Sutomo;PUJIONO Eko;SAPUTRA Muhammad Hadi;HUMAIDA Nida;HADI Etik Erna Wati;KURNIAWAN Hery;KUSWANDI Relawan;SUKMAWATI Jalma Giring;PRIHATININGSIH Wahyu Retno;ISWANI Sri;
Tropical coastal ecosystems,vital habitats for economically significant marine species,face increasing threats from eutrophication driven by human-induced nutrient pollution.This study investigated the metabolomic profile of Anadara granosa,a marine bivalve,to identify metabolites indicative of eutrophic conditions.Conducted in Cirebon Bay,Indonesia,the research spanned five locations reflecting varying eutrophication levels.Bottom-layer water samples were analyzed for pH,dissolved oxygen,salinity,water transparency,and nutrient concentrations (phosphate,nitrate,ammonia).Proton-Nuclear Magnetic Resonance (Proton-NMR)metabolomics of A.granosa revealed metabolite variations linked to water quality.Eutrophic conditions,prevalent in the bay’s northern side,were characterized by inorganic nitrogen levels above 0.2 mg L~(-1) and phosphate exceeding 0.024 mg L~(-1).These were linked to urban,aquaculture,and agricultural runoff,driving increased phytoplankton biomass and reduced salinity variability.Metabolomic analysis identified inosine and dimethylglycine as potential biomarkers.Elevated inosine levels in eutrophic environments suggest increased cellular activity due to greater food availability,while higher dimethylglycine concentrations detected in low-nutrient as its role in osmotic regulation.Both metabolites correlated with ammonia concentrations (P<0.05,R2=0.631),a key contributor to eutrophication.These findings highlight inosine and dimethylglycine as effective indicators of nutrient enrichment,providing insights into eutrophication’s impact on coastal ecosystems and A.granosa’s physiological responses.
2025年02期 v.24 506-514页 [查看摘要][在线阅读][下载 611K] - RAMZAN Muhammad Naeem;SHEN Ding;WEI Yingzhen;EMMANUEL Arslan;YANG Wen;ZHU Jinyong;WANG Yangcai;ZHENG Zhongming;
Mariculture tailwater poses significant environmental challenges such as water pollution and eutrophication.Photosynthetic bacteria(PSB) have been widely used for pollutant treatment.The integrated aquaculture wastewater bioremediation system(IAWBS) consists of four key components:sedimentation,biofilm,shellfish,and macro-algae.However,there is still some room for improvement in the treatment efficiency of the IAWBS.In this study,PSB(Rhodopseudomonos,Rhodobacteria,Rhodococcus) were added to the system.High-throughput amplicon of 16S rRNA,PERMANOVA,NMDS and other statistical analyses were used to investigate the impacts of PSB.The results showed that significant removal efficiencies of COD_(Mn),NH_(4+)-N,NO_3~--N,NO_2~--N,PO_4~(3-)-P were 71.42%,91.37%,91.72%,87.20%,and 88.80%,respectively.The impact of PSB on bacterioplankton community(BC)was not affected by the time interval but affected by different units,Proteobacteria,Bacteriodia and Actinobacteria were the most abundant phyla in all the units.Alpha diversity underscored a significant decrease in bacterial community diversity due to the PSB.Notably,the PERMANOVA analysis highlighted a significant interaction between the time interval and treated unit,influencing the composition of the microbial community(R~2=0.152;P=0.001).This study provides a better understanding of the role of photosynthetic bacteria in an integrated bioremediation system that can effectively treat mariculture tailwater,which is of great significance for the sustainable development of aquaculture.
2025年02期 v.24 515-524页 [查看摘要][在线阅读][下载 676K] - YUAN Chao;HUANG Juan;WU Lingjuan;XIAO Jie;ZHANG Xuelei;GAO Song;LI Yifei;XU Jiangling;WANG Zongling;
Harmful macroalgal blooms caused by Ulva prolifera and Sargassum horneri are increasing in the Yellow Sea and East China Sea. However, our understanding of macroalgal blooms before 2008 is fragmented and unclear. Using time-series Landsat imagery from 1984 to 2008, we examined macroalgal bloom events and their evolutionary patterns. The results suggest that no macroalgal blooms were observed before 1999. Ulva blooms could be traced back to 1999 and occurred on a small scale in 2000, 2004 and 2005, before escalating into large green tides in 2007 and 2008. Notably, these Ulva blooms were confined to the southern Yellow Sea from May to August. In comparison, Sargassum blooms were first detected in the East China Sea in March 2000 and occurred almost every year thereafter, although the size of the blooms showed significant interannual variation. The distribution areas generally moved northwards from March until the bloom dissipated in May or June, suggesting the influence of the monsoon and currents. Our investigation provided some insight into the bloom history of these two harmful macroalgal blooms in the Yellow Sea and East China Sea.
2025年02期 v.24 525-531页 [查看摘要][在线阅读][下载 778K] 下载本期数据