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海洋浮游植物支撑着海洋生态系统的正常运转,对其种类的定性识别、鉴定和细胞数量的定量分析是海洋科学研究中最为关键的科学问题之一。流式影像术在海洋浮游植物形态特征识别与快速定量检测上是目前先进和可行的方法,它综合了流式细胞术和图像显微识别的技术优点,不但能够对快速流动状态中的海洋浮游植物进行相应的参数检测,而且可以获取流动过程中清晰的图像,通过计算机软件的图像处理和特征筛选,实现海洋浮游植物有效的自动识别。通过对流式影像术的原理、测定方法、技术特点及其发展动态等的综述,认为基于流式影像术对高速运动的浮游植物图像的清晰实时采集,可以有效地对图像进行模式的识别和分类。它是一种理想和实用的方法,将为海洋生物学研究提供新的实时、快速、高效平台,有很好的应用前景。 相似文献
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流式细胞术在海洋浮游植物研究中的应用 总被引：2，自引：0，他引：2
流式细胞术在海洋浮游植物研究中的应用张利华（华东师范大学，河口海岸国家重点实验室，上海，２０００６２）生物学的研究已进入细胞分子研究的新纪元，从传统的定性描述发展到对细胞的各种形态参数与生物学特征、生化组成以及细胞功能等方面进行定量研究，其研究手段在... 相似文献
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通过小波变换可对信号的不同频率成分进行分解,为弱信号特征提取提供了有效途径。通过db7小波对分属7个门32个属的43种浮游植物的三维荧光光谱进行分析,后经Bayes判别分析选择小波分解后的第三层尺度分量作为最佳荧光识别特征谱,并通过系统聚类法将最佳特征谱在不同的条件下聚类进而得到门、属上的标准谱库。基于此,运用多元线性回归辅以非负最小二乘法建立浮游植物三维荧光光谱识别技术。利用该技术对4128个单种浮游植物样品和636个混合浮游植物样品进行识别分析。单种浮游植物样品在属水平上的识别正确率为75%,门水平上的识别正确率为95%;浮游植物混合样品中的优势种在属水平上的识别正确率为83%,门水平上的识别正确率为91%。结果表明:该技术可以实现对浮游植物的快速准确识别。 相似文献
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利用叶绿素资料计算初级生产力 总被引：9，自引：0，他引：9
海水中浮游植物叶绿素浓度是海洋生物调查中的一个重要观测参数，它不仅是表征浮游植物生物量的一个指标，而且利用它与浮游植物光合作用之间的相互关系还可以估算水域初级生产力，目前许多学者正致力于利用叶绿素资料计算初级生产力的研究，本文阐述根据叶绿素浓度计算初级生产力的方法，Ｒｙｔｈｅｒ－Ｙｅｎｔｓｃｈ模式，生态学数理模式和遥感模式，文章对方法应用中一些问题作了分析讨论。 相似文献
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传统的显微镜技术是浮游植物鉴定的重要手段 ,至今仍是浮游生物学家们进行研究观测的必备工具 ,但当研究较小的微型藻类(nanophytoplankton,<20μm)及微微型藻类(picophytoplankton,<2μm)时 ,常规显微镜则存在困难 ,如水体中光合性的细菌必需染色才能通过荧光显微镜观测 ,而且 ,当研究涉及时间、空间尺度时 ,牵涉到的工作量非常大 ,显微镜方法在物种计数的速度与准确性方面受到很大限制。近年的文献检索表明 ,应用流式细胞计(FlowCy tometry,FCM)检测微型及微微型的浮游植物正为越来越多的研究者所采用。流式细胞计以其快速、样品制备简… 相似文献
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随着PDC钻头的推广使用,传统的岩屑录井方法已难以分析如此细小的岩屑。基于数字图像处理技术对岩屑分类识别技术进行研究,首先利用和差直方图统计方法对岩屑进行纹理特征分析和提取,接着运用贝叶斯分类器进行分类识别,实验结果表明,此统计特征提取方法对于大部分岩屑可以很好地获取其主要特征,并最终取得理想的识别结果。此技术的发展将提高现场录井人员的工作效率和识别准确率。 相似文献
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选取db3小波函数,对分属7个门32个属的43种我国近海常见的优势藻种和赤潮藻种的3-D荧光光谱进行分解,提取小波分解后得到的第2,3层尺度分量作为荧光特征谱。再通过系统聚类的方法分别得到门类和属类层次上的标准谱。在此基础上,利用非负最小二乘法解析的多元线性回归方法建立了浮游植物荧光识别测定的技术。结果表明,利用db3小波函数分解并提取荧光光谱特征,从而在门类水平建立起来的标准谱库,对于单种藻样品的识别正确率平均为96.33%,对混合样品的识别正确率平均为84.27%。在属类水平上建立起来的标准谱库,对于单种藻样品的识别正确率平均为92.53%,对混合样品的识别正确率平均为69.60%。 相似文献
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海上紫菜养殖筏架分布无规律、大小不规则且数量较多，现场测量难度大、卫星影像空间分辨率低，不能精确测量出紫菜筏架面积。无人机机动性强、影像空间分辨率高，可在紫菜养殖调查中发挥重要作用。本研究以连云港海州湾紫菜养殖筏架为研究对象，开展可见光波段在养殖筏架与水体的光谱可区分度研究，基于6种植被指数，进行自动提取实验，以目视解译结果作为真值，进行精度分析，同时利用不同时相、不同区域的无人机可见光影像，开展方法的普适性研究。结果表明：绿色度坐标（green， G）和植被（vegetativen，VEG）指数方法在浅水区和深水区均表现较好，养殖筏架个数识别精度、面积识别精度均超过91.00%。基于此，利用上述两种方法，开展其他区域自动提取实验，养殖筏架个数识别精度、面积识别精度分别超过93.02%和89.37%。结果验证了无人机可见光影像可以实现紫菜养殖筏架的自动提取，精度基本满足紫菜养殖调查需求。 相似文献
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为了评估海洋酸化和富营养化耦合作用对近海浮游生态环境的影响,本研究以天津市近岸海域浮游植物群落的生物地球化学指标为研究对象,分别采用一次性及连续培养的方式模拟自然水华及稳态条件,探究其对二氧化碳(CO2)和硝酸盐浓度变化及二者耦合作用的响应。实验条件设置如下:1)对照:二氧化碳分压p(CO2)40.53 Pa、无硝酸盐添加;2)酸化:p(CO2)101.3 Pa、无硝酸盐添加;3)加N:p(CO2)40.53 Pa、添加硝酸盐50 μmol·L–1;4)酸化加N:p(CO2)101.3 Pa、添加硝酸盐50 μmol·L–1。实验结果表明,硝酸盐加富比酸化更加显著地促进浮游植物群落总叶绿素(Chl a)生物量及颗粒有机碳(POC)和颗粒有机氮(PON)积累,酸化和加N使浮游植物群落粒径大小升高。连续培养实验表明,酸化和N加富对Chl a、生物硅(BSi)、PON浓度、PON与颗粒有机磷(POP)比值(N/P)、POC与BSi比值(C/BSi)及沉降速率有协同交互作用,对POP和POC浓度及POC与PON比值(C/N)有拮抗性交互作用。在一次性培养后,酸化显著降低了浮游植物群落的沉降速率;而在连续培养后,酸化和N加富使浮游植物群落沉降速率显著升高。这些结果表明酸化和N加富对与近岸浮游植物相关的生物地球化学循环及在不同生长阶段的种群碳沉降存在不同的潜在影响及交互效应。 相似文献
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Fishery along the west coast of India largely depends on pelagic fish such as oil sardines, which are dominant during the south‐west monsoon. However, the response of sardine population to the warming caused by the climatic events such as El Niño/Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) is poorly studied. Here, we hypothesize that the ENSO‐related changes in biogeochemistry can adversely affect the oil sardines. We have used biogeochemical data collected along the Kerala coast during September 2015 (ENSO year) and September 2017 (a normal year) supported by catch per unit effort (CPUE) and fishery landing data to show the ENSO‐related bio‐physical dynamics and its impact on the oil sardine population along the south‐west coast of India. During the 2015 ENSO year, upwelling velocity decreased minimizing cooling of surface waters and resulted with an increase in sea surface temperature (SST) (~1.8°C). Consequent decrease in nutrient levels favoured nano‐phytoplankton and pico‐phytoplankton. On the other hand, during September 2017 when the ENSO effect was nullified, the decreased SST and availability of nutrients in the euphotic zone resulted in the dominance of micro‐phytoplankton. The hydrographic conditions (reduction in upwelling intensity), and reduction in micro‐phytoplankton abundance and zooplankton density in turn perhaps affected the fishery potential of the region. Oil sardines population (along the west coast) collapsed from 1.55 lakh tones (2014) to 0.46 lakh tones during 2015–2016 ENSO event, while in 2017 the conditions become favorable and their population was back to normal (1.27 lakh tones). Our results are in close agreement with our hypothesis and suggest that ENSO events could reduce phytoplankton productivity and disrupt the food chain, which in turn can affect the oil sardine population along the west coast of India. 相似文献
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The planktonic food web structure in the subarctic coastal water off Usujiri south-western Hokkaido, Japan was investigated from June 1997 to June 1999, based on seasonal biomass data of pico- (<2 µm), nano- (2–10 µm), micro- (10–200 µm) and mesoplankton (>200 µm), and path analysis using the structural equation model (SEM). In spring, microphytoplankton predominated due to diatom bloom, while pico- and nanophytoplankton predominated in the other seasons, except November and December 1997. The seasonal change in size distribution of heterotrophic plankton was almost similar to that of phytoplankton, and mesozooplankton biomass was high in spring. The path analyses suggest that the main channel in the microbial food web could vary according to phytoplankton size composition, indicating not only the classical food chain (microphytoplankton - copepods) but also the indirect route (microphytoplankton - naked dinoflagellates - copepods). 相似文献
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S. A. Ermakov I. A. Kapustin T. N. Lazareva I. A. Sergievskaya N. V. Andriyanova 《Izvestiya Atmospheric and Oceanic Physics》2013,49(3):307-314
Complex experimental studies of the influence exerted by phytoplankton on microwave backscattering from the water surface are carried out. Quantitative data on the concentration and group composition of the phytoplankton in the Gorky Reservoir during its eutrophication are obtained. It is established that the velocity of damping of gravity-capillary waves increases as the phytoplankton concentration increases, in which case the rise in the coefficient of damping of gravity-capillary waves is caused by an increase in both the effective viscosity of water and the value of elasticity of surface films related to the phytoplankton. It is established that, under the same weather conditions, the intensity of a radar signal decreases in the areas where the phytoplankton concentration is high. The results of model calculations of contrasts in the spectrum of wind gravity-capillary waves and the intensity of a radar signal are presented with respect to the phytoplankton concentration using the reconstructed values of the effective viscosity of water and the elasticity of films in the eutrophication zones, which describe the observational data satisfactorily. 相似文献
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Koji Suzuki Akira Hinuma Hiroaki Saito Hiroshi Kiyosawa Hongbin Liu Toshiro Saino Atsushi Tsuda 《Progress in Oceanography》2005,64(2-4):167
To verify the hypothesis that the growth of phytoplankton in the Western Subarctic Gyre (WSG), which is located in the northwest subarctic Pacific, is suppressed by low iron (Fe) availability, an in situ Fe fertilization experiment was carried out in the summer of 2001. Changes over time in the abundance and community structure of phytoplankton were examined inside and outside an Fe patch using phytoplankton pigment markers analyzed by high-performance liquid chromatography (HPLC) and flow cytometry (FCM). In addition, the abundance of heterotrophic bacteria was also investigated by FCM. The chlorophyll a concentration was initially ca. 0.9 μg l−1 in the surface mixed layer where diatoms and chlorophyll b-containing green algae (prasinophytes and chlorophytes) were predominant in the chlorophyll biomass. After the iron enrichment, the chlorophyll a concentration increased up to 9.1 μg l−1 in the upper 10 m inside the Fe patch on Day 13. At the same time, the concentration of fucoxanthin (a diatom marker) increased 45-fold in the Fe patch, and diatoms accounted for a maximum 69% of the chlorophyll biomass. This result was consistent with a microscopic observation showing that the diatom Chaetoceros debilis had bloomed inside the Fe patch. However, chlorophyllide a concentrations also increased in the Fe patch with time, and reached a maximum of 2.2 μg l−1 at 5 m depth on Day 13, suggesting that a marked abundance of senescent algal cells existed at the end of the experiment. The concentration of peridinin (a dinoflagellate marker) also reached a maximum 24-fold, and dinoflagellates had contributed significantly (>15%) to the chlorophyll biomass inside the Fe patch by the end of the experiment. Concentrations of 19′-hexanoyloxyfucoxanthin (a prymnesiophyte marker), 19′-butanoyloxyfucoxanthin (a pelagophyte marker), and alloxanthin (a cryptophyte marker) were only incremented a few-fold increment inside the Fe patch. On the contrary, chlorophyll b concentration reduced to almost half of the initial level in the upper 10 m water column inside the Fe patch at the end of the experiment. A decrease with time in the abundance of eukaryotic ultraphytoplankton (<ca. 5 μm in size), in which chlorophyll b-containing green algae were possibly included was also observed by FCM. Overall, our results indicate that Fe supply can dramatically alter the abundance and community structure of phytoplankton in the WSG. On the other hand, cell density of heterotrophic bacteria inside the Fe patch was maximum at only ca. 1.5-fold higher than that outside the Fe patch. This indicates that heterotrophic bacteria abundance was little respondent to the Fe enrichment. 相似文献
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Three experimental ecosystem enclosures were employed to test the effects of Bohai crude oil on the structure of phytoplankton community. The results indicate that, while the species composition were changed (from larger diatoms to microflagellates or smaller diatoms), the species diversity and the total cell number of phytoplankton community were practically unchanged. All of the effects of oil disappeared in 12 days. 相似文献
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Fatty acids present in suspended particles were examined following the onset of a phytoplankton bloom in an experimental marine mesocosm set up in Patricia Bay, Saanich Inlet, British Columbia, Canada. The predominantly diatom bloom, triggered by the addition of nutrients at the commencement of the experiment, was succeeded by several other phytoplankton forms, which in turn led to changes in particulate chl a, and organic carbon, and nitrogen within the experimental enclosure. An examination of individual fatty acids indicated that the variation of individual fatty acids can be classified into three groups, although the variation pattern of individual fatty acids differed from one another. An attempt was made to establish the factors controlling particulate fatty acid concentrations by principal component analysis. After Varimax rotation, six factors were extracted, of which four factors contributed to 83% of the data matrix. These were mainly dependent on the source of the particles i.e., diatoms, dinoflagellates, and bacteria.Fatty acid concentrations obtained by analysis of different lipid class fractions indicated that the production of fatty acids was distinctly related to the growth stage of the phytoplankton bloom. Fatty acids in triglycerides peaked during stationary phase, whereas fatty acids in polar lipids were high during the stage of an increase of phytoplankton biomass. However, fatty acid composition in both lipid classes changed under the influence of species succession of the phytoplankton population. This strongly suggested that species succession of the phytoplankton exerted the most significant control on fatty acid composition of particulate matter. 相似文献
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稀释法(dilution technique)是研究微型浮游动物摄食和浮游植物生长的常用方法之一,负值浮游植物生长率是稀释实验中常见的现象。分析了造成负值生长率出现的因素,以及这些因素对实验结果的影响,并提出了防止不利影响产生的措施。负值生长率的出现不能简单地视为实验失败的标志,培养光照和温度条件、取样误差、无颗粒水污染、营养盐污染和限制等都可能造成负生长率的出现,且对实验结果的影响不同。同时,根据实验结果,演示浮游植物光适应、取样误差、无颗粒水污染和加富营养盐对稀释实验的影响。结果显示,光照条件可以改变细胞色素含量,且不同浮游植物类群对光照条件的响应不同,从而导致基于色素分析的稀释实验结果出现误差;取样混合不均,可造成取值偏低,导致浮游植物生长率估值偏低,甚至为负值,但可能不影响对摄食率的估算。另外,实验污染(无颗粒水和加富营养盐污染)往往会抑制浮游植物生长,甚至造成浮游植物死亡。因此,培养条件模拟和人为干扰控制是稀释实验成功的关键。 相似文献
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基于模糊C均值聚类的云图样本修正与云类自动识别 总被引：5，自引：0，他引：5
基于云类样本的红外-可见光二维灰度空间投影,采用模糊聚类方法调整优化云类样本特征区域,消除采样误差。针对常规模糊C均值聚类(FCM)方法在处理上述问题时表现出的局限性,提出用样本特征均值替代FCM中随机初始中心的改进办法,既避免了常规FCM方法对初始中心敏感的缺陷,又可纠正其聚类结果对云类样本特征结构的歪曲。改进后的聚类结果既消除了采样误差,又保持了云类样本的基本特征属性。基于该判据的分类结果,可较为准确地分辨出陆地、水体、低云、中云、卷云、对流云和积雨云,分割判另9结果符合客观实际。 相似文献