Subjects: Geosciences >> Marine Sciences submitted time 2023-08-15
Abstract： Based on the OSMAC strategy, this paper explores and investigates the structurally novel compounds in the secondary metabolites of Cladosporium sp. SCSIO41206, a coral-associated fungus from the Beibu Gulf. The Secondary metabolites of the bacterium were isolated and purified by various chromatographic techniques, and the compounds were identified by NMR, MS and data comparison with relevant literature. The research results showed that this fungus produced richer metabolites when cultured in the Potato Glucose Water (PBD) Liquid Culture Medium and incubated at 26°C for 30 days. Through isolation and identification, twelve known monomeric compounds were obtained, namely3-isobutylhexahydropyrrolo(1,2-a)pyrazine-1,4-dione(1);3-benzyl-7-hydroxyhexahydropyrrolo(1,2-a)pyrazine-1,4-dione(2);cyclo(L-proline-L-4-hydroxyproline)dipeptide(3);cyclo(L-proline-glycine)dipeptide(4);cyclo(D)-Pro-(D)-Ile(5);cyclo(phenylalanine-glycine)dipeptide(6);cyclo-(4-S-hydroxy-R-proline-R-isoleucine)(7);N-phenethylacetamide(8);N-hydroxy-2-(hydroxyimino)-4-methylpentanamide(9);quinolactacin A1(10); quinolactacin A2(11); Dibutylterephthalate(12). Compounds 10-12 were isolated for the first time from Cladosporium sp., a branch fungus obtained from the Beibu Gulf coral. Compounds 2、3、4、8、10、11 and 12 showed weak inhibitory activity against acetylcholinesterase.
Peer Review Status:
Awaiting Review
Subjects: Geosciences >> Marine Sciences submitted time 2023-06-05
Abstract： We used COI marker and mitochondrial control region (CoReg) marker to determine genetic structure and genetic diversity of Crown-of-thorns starfish (Acanthaster planci) (Asteroidea, Spinulosa) in the northwest South China Sea, the geographical population of A. planci among six locations: including Bombay Reef - LH, Discovery Reef - HG, Vuladdore Reef - YZ, Observation Bank - YY, Luhuitou Peninsula - LHT, Lincoin Island – DD, were preliminarily studied, and the causes are discussed. We amplified the DNA sequences of 81 individuals from six populations, 81 COI sequences with a length of 622bp and 81 CoReg sequences with a length of 583bp were obtained. The analysis of two mitochondrial markers showed that there is a diversity of differences within the geographic population (COI: h: 0.286-0.824, π: 0.00119-0.00272, k: 0.743-1.692; CoReg: h: 0.286-0.846, π: 0.00686-0.01457, k: 4-13.79), CoReg sequence fragments show higher diversity, geographic population DD shows the highest diversity, there is a certain genetic structure between geographic populations (COI: FST: -0.00394-0.40513; CoReg: FST: 0.11198-0.78571). The haplotype network diagram and STRUCTURE analysis show that the geographic populations of A. planci in the Northwest South China Sea may be divided into two genetic lineages, with the results of AMOVA analysis support a high level of genetic communication among the geographic populations of A. planci in the northwest South China Sea. Migration is used to predict a gene flow route from geographic population LH and YZ in the Xisha Islands to geographic population LHT through geographic population YY in the northwest direction. The surface currents in the South China Sea provids impetus for the inter-population dispersal of A. planci larvae, which further construct the gene flow model of A. planci in the northwest South China Sea.
Subjects: Geosciences >> Marine Sciences submitted time 2023-05-31
Abstract： Quantifying eddy mixing in the ocean is a hot and tough problem in the area of physical oceanography. Based on the theory of effective diffusivity, the present study investigated the stirring effects of geostrophic turbulence that lead to stretching, distorting, deforming, and folding of tracer contours. These changes are then related to the efficiency of turbulent mixing. Results show that under the stirring effect of geostrophic turbulence, the length of tracer contour can be quickly elongated and fine-scale tracer filaments and fronts are also generated. This fractal elongation of tracer contour, about 10-20 times longer than the original length, is the dominant contributor to the mixing efficiency, whereas the gradient enhancement associated with filament and front generations only plays a secondary role. On the other hand, fine-scale features are smoothed out by small-scale diffusivity which eventually suppresses the increase of contour length and the generation of tracer filaments. This imposes an upper bound of the mixing efficiency when the stirring and smoothing effects are in a dynamical balance. Through a ‘box-counting’ method, the fractal dimension of tracer contour is also found between 1.4~1.6, indicating a geometric dimension lies somewhere between 1D and 2D. Due to the limitation of data resolution, contour length and thus mixing efficiency may be underestimated. Finally, the present study made an empirical relation between the fractal dimension and mixing efficiency, providing an opportunity for estimating mixing efficiency through a well-developed pattern recognition technique in remote sensing, and a new way of diagnosing ocean mixing and its parameterization.
Subjects: Geosciences >> Marine Sciences submitted time 2023-05-09
LIU, Ying
ZHU, Zhenxin
WANG, Cong
LIU, Hongcun
JIANG, Mingguo
ZHU, Yuzhang
LIN, Kun
LU, Xiaomei
LIANG, Haina
YANG, Lifang
Abstract： To study active secondary metabolites of marine actinobacteria Streptomyces sporoverrucosus 33510, and evaluate antibacterial activity of the purified compounds. The Streptomyces sporoverrucosus 33510 strain was tested for antibacterial activity. Streptomyces sporoverrucosu 33510 shows strong inhibitory activity against various plant pathogenic bacteria. The compounds were isolated and purified by high performance liquid chromatography (HPLC), semi-pre HPLC, thin-layer chromatography (TLC) and resortification technology. And their chemical structures were characterized by nuclear magnetic resonance (NMR) analysis. The chemical structures were identified as bisphenol A (1), 2-(4-methoxyphenyl)acetic acid (2), N-phenethylacetamide (3), methyl 2-(1H-indol-3-yl)acetate (4), dibutyl phthalate (5), cyclo(D)-pro-(D)-Leu (6), cyclo(D-Pro-L-Leu) (7), cyclo-(D-ProL-Ile) (8), cyclo(L-Pro-L-Phe) (9), cyclo-(L-Leu-L-Val) (10). Except for the compounds 5 and 9, the remaining eight compounds were isolated from Streptomyces sporoverrucosus for the first time. The antibacterial activity of the compounds were tested for by Disk Diffusion Assay. Compound 3, 4, 5, and 6 show antibacterial activity against Rhizoctonia solani. Compound 7, 8, and 9 show antibacterial activity against Cryphonectria parasitica. Compound 3 and 7 show antibacterial activity against Fusarium pseudograminearum. Marine actinomycetes Streptomyces sporoverrucosus 33510 can be a potential resource for antibacterial drugs.
Subjects: Geosciences >> Marine Sciences submitted time 2020-11-25 Cooperative journals: 《干旱区科学》
SHURIGIN,Vyacheslav
EGAMBERDIEVA,Dilfuza
LI,Li
DAVRANOV,Kakhramon
PANOSYAN,Hovik
BIRKELAND,Nils-K?re
WIRTH,Stephan
BELLINGRATH-KIMURA,Sonoko D
Abstract： Endophytic bacteria of halophytic plants play essential roles in salt stress tolerance. Therefore, an understanding of the true nature of plant–microbe interactions under extreme conditions is essential. The current study aimed to identify cultivable endophytic bacteria associated with the roots and shoots of Seidlitzia rosmarinus Ehrenb. ex Boiss. grown in the salt-affected soil in Uzbekistan and to evaluate their plant beneficial traits related to plant growth stimulation and stress tolerance. Bacteria were isolated from the roots and the shoots of S. rosmarinus using culture-dependent techniques and identified by the 16S rRNA gene. RFLP (Restriction Fragment Length Polymorphism) analysis was conducted to eliminate similar isolates. Results showed that the isolates from the roots of S. rosmarinus belonged to the genera Rothia, Kocuria, Pseudomonas, Staphylococcus, Paenibacillus and Brevibacterium. The bacterial isolates from the shoots of S. rosmarinus belonged to the genera Staphylococcus, Rothia, Stenotrophomonas, Brevibacterium, Halomonas, Planococcus, Planomicrobium and Pseudomonas, which differed from those of the roots. Notably, Staphylococcus, Rothia and Brevibacterium were detected in both roots and shoots, indicating possible migration of some species from roots to shoots. The root-associated bacteria showed higher levels of IAA (indole-3-acetic acid) synthesis compared with those isolated from the shoots, as well as the higher production of ACC (1-aminocyclopropane-1-carboxylate) deaminase. Our findings suggest that halophytic plants are valuable sources for the selection of microbes with a potential to improve plant fitness under saline soils.
Subjects: Geosciences >> Marine Sciences submitted time 2017-07-17
Abstract： In order to deal with the quality of Antarctic krill during the storage and transportation process caused by the failure of the supply system and the freezing equipment in the process of storage and circulation in the form of frozen products, the project team changed the refrigerated environment to the Antarctic The effect of krill quality was studied. When the ambient temperature increased from -20 ℃ to -12 ℃, -7 ℃, -3 ℃, -1.5 ℃, 0 ℃, 1 ℃, 2.5 ℃, 4 ℃, 6 ℃ , 8 ℃, 12.5 ℃, 16 ℃, the Antarctic krill samples for sensory evaluation, pH value, the meat rate and soup turbidity and other quality indicators of the determination. The results show that when the ambient temperature from -20 ℃ up to -1.5 ℃ process, the Antarctic krill soup after cooking is more clear, little change in turbidity, pH quickly increased from 7.60 to 7.85 Antarctic krill muscle elasticity began to change Poor, the sensory quality has begun to change from good to change; when the temperature from -1.5 ℃ to 4 ℃, the pH value slowly increased, there is a certain fluctuation, may be due to differences in the composition of the various components of the decision, Antarctic krill soup after the soup turbidity quickly increased from 0.5 to 0.7Brix maximum, sensory quality is still at a moderate level; when the temperature rose to 16 ℃, the pH has risen to 8.05, Antarctic krill Sensory quality from the change into a bad, this time the Antarctic krill has been unable to eat, only as a feed or other use.
Peer Review Status:Awaiting Review
Subjects: Geosciences >> Marine Sciences submitted time 2017-07-17
Abstract：From August 25 to 29, 2014, the project team carried out the experiment of Antarctic krill trawl in the Beihai Bay of the South China Sea. In order to understand the flow field of the network model in the course of the experiment, it is necessary to record the speed of the ship and to grasp the flow field of the ocean. Therefore, the ocean velocity is measured during the experiment. The flow rate in this experiment was measured using an acoustic Doppler flowmeter (Vectrino Plus, Nortek, Norway). In order to compensate for the flow rate error caused by ship drift, the drift condition of the ship was also measured by the positioning device (Snapdragon MSM8274AB, Qualcomm, USA) used in the flow rate measurement. The results show that the actual velocity of the target sea area is in the range of 0.06-0.49 m / s and the direction is 216.17-351.70. And compared with the previous research, the influencing factors were analyzed. This study proves that it is feasible to use point Doppler flowmeter for velocity study in trawl model experiment.
Peer Review Status:Awaiting Review
Subjects: Geosciences >> Marine Sciences submitted time 2017-04-10 Cooperative journals: 《材料研究学报》
Abstract：采用线性离子束技术在 PET 基材表面制备类金刚石薄膜，分析薄膜结构、性能随离子束电流的演变规律 并研究了薄膜润湿特性与表面形貌、结构、表面能的作用关系。结果表明:沉积在 PET 表面的类金刚石薄膜具 有典型的非晶碳膜结构特征，随着离子束电流的增大 sp2/sp3 比值由 0.774 增加到 1.622，薄膜表面的石墨化程度 提高;改性后的 PET 材料接触角从 63.51°增大到 103.7°。进一步分析发现，疏水性能的提高归因于材料表面能 的降低，表面石墨化程度的提高和微-纳结构的形成是表面能降低的根本原因。此外，疏水的 PET 材料在 500~ 760 nm可见光范围内具有一定的増透效果，透过率达到88.5%以上。用线性离子束沉积碳膜及刻蚀技术能得 到合适的微观形貌和表面化学结构，可在保持基体材料透明性的同时提高 PET 柔性聚合物材料的疏水性能。
Subjects: Materials Science >> Materials Science (General) Subjects: Geosciences >> Marine Sciences submitted time 2017-03-31 Cooperative journals: 《腐蚀科学与防护技术》
Abstract：运用开路电位、交流阻抗、阳极极化曲线和电化学频率调制技术研究了304不锈钢在不同温度（60~90℃）及不同海水（一级反渗透淡化海水、天然海水、1.6倍浓缩海水）中的点蚀行为。结果表明，304不锈钢在一级反渗透淡化海水中随着温度的升高点蚀敏感性增加；在发生点蚀前的钝化状态下，304不锈钢在一级反渗透淡化海水中比在海水中腐蚀严重；304不锈钢的点蚀敏感性随Cl-浓度的升高而增加；304不锈钢在80℃下的一级反渗透淡化海水中随浸泡时间的延长，腐蚀速率逐渐增大，且在浸泡1d时即有发生点蚀的倾向，在第10d时已经发生了点蚀。
Subjects: Geosciences >> Marine Sciences Subjects: Materials Science >> Materials Science (General) submitted time 2017-03-31 Cooperative journals: 《腐蚀科学与防护技术》
Abstract：采用失重分析、极化曲线测试和SEM分析手段，研究了模拟海洋大气环境下直流电场对碳钢初期腐蚀行为的影响。结果表明，直流电场的存在加速了碳钢的初期腐蚀速率，但并没有改变其腐蚀动力学；直流电场存在有利于具有亚稳片状结构的γ-FeOOH的形成，同时抑制了γ-FeOOH向具有保护性能的α-FeOOH的转化，从而导致锈层的保护性能下降，加速了碳钢的腐蚀。
Subjects: Geosciences >> Marine Sciences Subjects: Materials Science >> Materials Science (General) submitted time 2017-03-31 Cooperative journals: 《腐蚀科学与防护技术》
Abstract：通过海水飞溅区暴露试验，获得了2种含镍钢和碳钢3a的腐蚀结果。采用X-射线衍射（XRD）和电子探针显微分析（EPMA）技术，研究了含镍钢飞溅区锈层的特性，讨论了Ni对钢飞溅区锈层及耐蚀性的影响。结果表明，添加2%~3%Ni，使钢锈层中的裂纹和孔洞减小, 锈层的致密度提高；外锈层中的?-FeOOH的含量增加。2%~3%Ni的加入有利于盐分中的Na+和Mg++向锈层和钢基体界面渗透，对Cl?的渗透有抑制作用。添加3%Ni，使钢的蚀孔中的Cl?富集程度显著降低。加入2%~3%Ni能大幅度提高钢在飞溅区的耐蚀性。
Subjects: Geosciences >> Marine Sciences Subjects: Materials Science >> Materials Science (General) submitted time 2017-03-31 Cooperative journals: 《腐蚀科学与防护技术》
Abstract：由于土壤成分的非均匀性，决定土壤中金属易发生非均匀腐蚀。本文利用阵列电极技术与腐蚀埋片相结合的方法，以碳钢Q235为研究材料，经自然热带临海红壤埋片，研究了碳钢Q235的宏观非均匀腐蚀行为。碳钢Q235材料在时间维度上和垂直地面的空间维度上皆发生非均匀腐蚀。时间维度上发生非均匀腐蚀的原因是降雨频率与降雨量对土壤湿度的影响，从而影响碳钢Q235材料腐蚀的环境；垂直地面的空间维度上发生非均匀腐蚀的原因是随土壤深度增加，土壤湿度变化、含氧量变化及土壤组成成分差异的影响。在0-90cm深度土壤范围内，随土壤深度的增加，碳钢Q235材料的腐蚀速率增加。垂向埋于热带滨海红壤中的长尺寸碳钢Q235材料在30cm-50cm、80cm和 140cm-150cm三个范围内，因电偶腐蚀影响，腐蚀速率较大。
Subjects: Geosciences >> Marine Sciences submitted time 2017-03-31 Cooperative journals: 《腐蚀科学与防护技术》
Abstract：通过静态浸泡腐蚀实验以及极化曲线测试、电化学阻抗谱测试、Mott-Schottky曲线等电化学测试技术，结合扫描电子显微镜技术研究了马氏体沉淀硬化不锈钢PH13-8Mo在不同pH值的0.5mol/L的Na2SO4溶液中的腐蚀行为。结果表明：PH13-8Mo的耐蚀性随着溶液pH值的升高而增强，不同的pH值能改变腐蚀的速率及腐蚀产物的形貌。随着溶液pH值的升高，腐蚀电流密度jcorr减小，极化电阻Rp增大，容抗弧的幅值增大，钝化膜中缺陷密度降低，钝化膜的致密性增强，耐腐蚀性能提高。
Subjects: Geosciences >> Space Physics Subjects: Geosciences >> Marine Sciences submitted time 2017-03-23
Abstract：海洋沉积物中天然气水合物的存在与分布与地温条件紧密相关。南海北部陆坡大部分区域更、全新世沉积速率较高，同时局部地区(如神狐天然气水合物钻探区)发育有大量的海底冲蚀谷。这些快速沉积或侵蚀作用可以对地温场及天然气水合物的形成与赋存产生重要影响，然而目前注意到这些问题的研究相对较少。本文中我们结合南海北部陆坡的实际情况，建立了针对地温场发生动态变化时的水合物成藏数值模型。我们给出两个成藏模拟案例，其一是快速沉积的情形，其二是地形遭受侵蚀、产生冲蚀谷时的情形。结果表明，在这两种情形下地温场将发生不同的瞬态调整，并对天然气水合物在地层中聚集及分布产状产生重要影响。在快速沉积发生时，地温梯度将变小，天然气水合物稳定带（HSZ）将增厚；然而当其底界将随着热传递而上升，天然气水合物将不断在原稳定带底界分解，而后在新的稳定带底界处重新生成水合物。这样长时间的快速沉积作用可以造成水合物主要富集在稳定带底界处。而当快速侵蚀作用发生时，地温梯度将变大，天然气水合物稳定带的厚度将变薄，原来位于冲蚀谷处的水合物藏将被侵蚀作用破坏。而后，随着热平衡的发展，逐渐形成新的、类似于似海底反射层的稳定带底界。单纯考虑甲烷扩散作用下，高丰度水合物的形成需要较长的时间，相对而言脊下的水合物成藏较好，形成矿点的概率较大。 The occurrence and distribution of gas hydrate in marine sediments is closely related to the state of geothermal field. The sedimentation rate is relatively high during the Pleistocene and Holocene in the northern margin of the South China Sea. Moreover, there are many erosional canyons at the sea bottom in some local areas. Such fast sedimentation and erosion can greatly affect the geothermal regime and the formation and occurrence of gas hydrate deposits. However, there are few studies that consider such scenarios. In this study, considering the geological reality, we build a numerical reservoir model aimed to simulate the evaluation of the gas hydrate system upon two cases: the fast sedimentation and the development of erosional canyons. The results indicate the geothermal filed and the accumulation and distribution of gas hydrate can be adjusted dynamically when the fast sedimentation or erosion occurs. Under fast sedimentation, the geothermal gradient becomes smaller and the thickness of gas hydrate stability zone (HSZ) becomes larger. However, due to the role of heat transfer, the bottom of HSZ rises upward. This process leads to the hydrate near the previous bottom of HSZ being dissociated and depositing near the bottom of new HSZ. After a long duration, the fast sedimentation will result the formation of hydrate being mainly enriched near the bottom of HSZ. By contrast, when fast erosion occurs, the geothermal gradient increases and the HSZ turn thinner. The gas hydrate deposit system can be partially destroyed by the formation of canyons. A long time is necessary for the recovery of a gas hydrate deposit with significant abundance. Relatively, the deposits under the residual ridges are more possible to be potential “sweet spots”.
Peer Review Status:Awaiting Review
Subjects: Biology >> Ecology Subjects: Geosciences >> Marine Sciences submitted time 2017-03-22 Cooperative journals: 《生态学报》
Abstract：江苏海门蛎岈山牡蛎礁是我国目前现存的面积最大的潮间带活体牡蛎礁，但由于人类活动干扰及泥沙淤积等原因，该自然牡蛎礁面积不断缩小，影响着该牡蛎礁的生态功能与保护管理。于2013-2014年开展了首期江苏海门蛎岈山牡蛎礁恢复工程，基于生态监测结果评估该牡蛎礁恢复工程的生态效果。多层礁体上活体牡蛎丰度显著高于单层礁体（P 0.05）。随着礁体的发育，恢复牡蛎礁上大型底栖动物群落的物种丰度并没有增加，但其平均总密度和总生物量均呈现显著性的增长（P 0.05），但显著高于未恢复区（P < 0.05）；恢复牡蛎礁与自然牡蛎礁具有显著不同的大型底栖动物群落（ANOSIM，P=0.001）。研究结果表明该牡蛎礁恢复工程取得初步成功。
Subjects: Biology >> Ecology Subjects: Geosciences >> Marine Sciences submitted time 2017-03-22 Cooperative journals: 《生态学报》
Abstract：从太平洋深海克拉里昂-克利伯顿断裂带（Clarion-Clipperton fracture zone，简称CC区）4个站位采集的深海沉积物样品中检出26条嘴刺目（Enoplida）线虫个体。综合应用形态学和分子生物学方法，共鉴定嘴刺目线虫6科8属，其中尖口线虫科（Oxystominidae）个体数量最多，占总数的57.7%，其次为前感线虫科（Anticomidae，19.2%）、光皮线虫科（Phanodermatidae，7.7%）、钩线虫科（Oncholaimidae，7.7%）、烙线虫科（Ironidae，3.8%）和矛线虫科（Enchelidiidae，3.8%）。科、属组成与相邻站点同期采样所获的线虫近似，而丰度组成比例有所差异。分子生物学方法获得了线虫rRNA基因序列16条，经GenBank数据库比对，其与已有的序列相似性范围为94%-99%，以此为依据可确定到科的水平和大部分属的水平（84.6%）。DNA条形码比对结果和形态学鉴定结果有较高一致性，表明分子条形码技术可作为深海线虫鉴定的有效手段。系统发育分析结果显示，基于18S和28S rRNA基因序列，采用不同方法构建系统发育树，其分支结构基本一致；钩线虫科和矛线虫科聚类在一起，光皮线虫科和前感线虫科聚类在一起，显示出彼此间较近的遗传关系。
Subjects: Geosciences >> Marine Sciences submitted time 2017-03-22 Cooperative journals: 《中国科学院院刊》
Abstract：水圈包括海洋、湖沼、河流、冰川、地下水等，水圈中居住着地球上一半以上的微生物，包括细菌、古菌、真菌、藻类、病毒等，蕴含着地球上最大的微生物组。已有的研究表明，水圈微生物在重要元素生物地球化学循环中发挥关键驱动作用。但是，人们对水圈微生物组的核心科学问题，即微生物如何发挥驱动作用至今了解不多。最近，国家自然科学基金委员会“水圈微生物驱动地球元素循环的机制”重大研究计划（简称“水圈微生物计划”）正式立项。该计划拟选择典型水圈环境，解析微生物群落构建及与环境之间的相互作用、微生物物质与能量代谢机制以及微生物代谢活动的生态学意义与贡献，从而揭示水圈微生物驱动碳、氮、硫等元素生物地球化学循环的机制。文章简述了该计划提出的背景与依据，以及涉及的主要科学问题和研究设想。
Subjects: Geosciences >> Space Physics Subjects: Geosciences >> Marine Sciences submitted time 2017-03-10
Abstract：在建立雷达高度计海况偏差(Sea State Bias, SSB)非参数模型时，通常会用到局部线性回归(Local Linear Regression, LLR)估计器，而传统的局部线性回归估计器涉及高维矩阵运算，当建模的数据量较大时，估计海况偏差需要大量的时间，从而使得非参数估计方法很难用于高维海况偏差模型。该文提出一种改进的局部线性回归(Improved Local Linear Regression, ILLR)估计器，可以避免传统的LLR估计器所需的高维矩阵运算，在不影响海况偏差估计结果的条件下，将局部线性回归估计器获取加权函数的时间复杂度由降低为，从而大幅地降低估计海况偏差所需的时间，为实现高维非参数海况偏差模型的实时运算奠定了基础。
Peer Review Status:Awaiting Review
Subjects: Geosciences >> Space Physics Subjects: Geosciences >> Marine Sciences submitted time 2017-03-10
Abstract：海况偏差(Sea State Bias,SSB)是雷达高度计测量海面高度的重要误差源。目前,业务化运行的雷达高度计的海况偏差校正都是采用基于风速(U)和有效波高(SWH)的2维经验模型方法,其海况偏差校正不确定度约为2cm。该文提出一种基于交叉点数据和3维非参数模型的海况偏差估计方法,该方法利用星下交叉点数据,采用基于U,SWH以及平均波周期(MWP)的3维非参数模型进行海况偏差估计。该文利用这种估计方法对Jason-2卫星雷达高度计2009~2011年3年的数据进行了处理,将处理结果与Jason-2卫星高度计的地球物理数据集(Geophysical Data Records,GDR)中的海况偏差校正项进行对比,结果表明该文提出的海况偏差估计方法平均能降低1.64 cm2的交叉点海面高度不符值的方差和0.92 cm2的沿轨海面高度异常值的方差,分别对应于1.28 cm和0.96 cm的均方根(RMS)海面高度,这对于提高高度计数据产品的精度具有重要意义。
Peer Review Status:Awaiting Review
Subjects: Biology >> Ecology Subjects: Geosciences >> Marine Sciences submitted time 2017-03-08 Cooperative journals: 《生态学报》
Abstract：Stoeckeria algicida为甲藻纲胸甲球藻科，有侵噬鱼类细胞杀鱼的能力，可导致鱼类成群死亡，同时也会杀死其他海洋微藻。由于该藻个体微小、形态学鉴定困难，研究较为迟缓，我国海域几乎没有该藻的研究报道。近几年，高通量测序技术的发展极大地推动了微型/微微型浮游植物的鉴定研究，为了解我国辽东湾海域是否存在Stoeckeria algicida及其分布情况，以18S rDNA V4区作为目标基因，结合高通量测序技术，专门设计了微型/微微型浮游植物鉴定引物对V4（F/R），随后对辽东湾2014年四季海水中微型和微微型浮游植物多样性进行了检测。结果发现，Stoeckeria algicida除了春季未检出外，其他季节均有检出，温度是影响该藻繁殖的主要因素。虽然Stoeckeria algicida在整个环境样品中优势度不太明显，但其夏季密度较高（最高达2.753×103个/L），高值区主要分布在辽东湾东西两岸，致灾风险较高，应引起有关方面足够重视。Stoeckeria algicida在我国海域首次报道，其危害后果严峻，必须加强监测监管。
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