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1.
廖永岩 《海洋科学》2003,27(4):68-71
利用面包酵母在室内高密度培养褶皱臂尾轮虫(Brachionus plicatilis),并用培养的轮虫进行远海梭子蟹育苗。结果发现,接种200个/mL,经8d培养,轮虫密度可达3075个/mL。用高密度培养而又未经营养强化的褶皱臂尾轮虫作为开口饵料及培养饵料,再配合单胞藻和卤虫,用于远海梭子蟹育苗,育苗期(至大眼幼体)为14-16d,培育至幼蟹一期,成活率达17%。  相似文献   

2.
实验生态条件下研究十溴联苯醚(BDE-209)的急性毒性胁迫对褶皱臂尾轮虫(Branchionus plicatilis)运动行为与摄食行为的影响,探讨可用以表征胁迫-响应的生物标志物。结果表明:(1)BDE-209胁迫24h显著性增加了褶皱臂尾轮虫的运动抑制率,由此得到24h半数有效抑制浓度(24h-EC_(50))为9.084mg/L,但未达到半数致死作用;(2)当分别以四种海洋微藻:小球藻(Chlorella vulgaris)、青岛大扁藻(Platymonas helgolandica)、等鞭金藻8701(Isochrysis galbana)和小新月菱形藻(Cylindrotheca closterium)为单一饵料来源时,褶皱臂尾轮虫对四种饵料单胞藻的滤水率(F)和摄食率(G)均随着胁迫时间和胁迫浓度的增加而不断下降,呈现出明显的浓度依赖性,说明BDE-209胁迫能显著抑制褶皱臂尾轮虫的摄食作用。(3)将其中三种微藻等生物量混合投喂时,褶皱臂尾轮虫对三种微藻的滤水率和摄食率与单一饵料投喂条件相比均发生变化,且对各种微藻的选食率(Sr)和摄食总生物量均随着胁迫时间和浓度的增加呈下降趋势,选择性指数(Si)发生变化,对小球藻的摄食选择性最高。滤水率的变化较其它指标更敏感,可用以指示浮游动物在个体水平上响应外源环境变化的标志物。结果表明,BDE-209胁迫能有效改变褶皱臂尾轮虫的摄食与选食行为,且其最适宜的饵料是小球藻。  相似文献   

3.
轮虫生产中两种益生菌的应用试验   总被引:1,自引:0,他引:1  
苏跃中  游岚 《台湾海峡》2001,20(Z1):76-79
鱼类在工厂化育苗中,用面包酵母进行褶皱臂尾轮虫(Brachionusplicatilis)的培养生产时,添加初始浓度为100×10  相似文献   

4.
真鲷仔鱼早期阶段的摄食能力──发育反应和功能反应   总被引:4,自引:1,他引:3  
于1995年4月 ̄1996年5月在中国水产科学研究院黄海水产研究所小麦岛苗种基地,采用梯度试验方法在不同褶皱臂尾轮虫饵料密度下2 ̄12日龄真鲷仔鱼的摄食率和摄食强度,通过拟合发育反应和功能反应模型模型的数据来评价真鲷仔鱼早期阶段的摄食能力。结果表明,从仔鱼开口2日龄至12日龄,摄食强度从0.316μg/h提高到1.374μg/h;摄食成功率从59%提高到70%,平均摄食发生率从0.469μ g/h  相似文献   

5.
棱梭对饵料摄食与吸收利用研究   总被引:1,自引:0,他引:1       下载免费PDF全文
本文采用~(14)C标记技术测定棱梭幼体对褶皱臂尾轮虫、卤虫和亚心形扁藻等饵料的摄衾率、吸收率扣利用率,并以~3H-葡萄糖和~(14)-苯丙氨酸作示踪剂研究人工配合饵料中葡萄糖和氨基酸在棱梭体内转运和分布情况。结果表明,卤虫、褶皱臂尾轮虫都是棱梭幼体合适的饵料;氨基酸更多地参与了棱梭组织中的细胞代谢,而葡萄糖则是棱梭体内重要的能源物质。  相似文献   

6.
褶皱臂尾轮虫(Brachionus plicatilis)是轮虫动物门(Rotifera)中的广盐种。其个体微小、培养容易、营养丰富,是目前唯一能够在海水养殖中进行大规模培养,并用于海产动物人工育苗的物种。褶皱臂尾轮虫生活史为孤雌生殖和有性生殖世代交替进行,是生物学研究的模型生物。本研究用FIASCO法构建了褶皱臂尾轮虫微卫星富集文库,分离了135个微卫星;用PCR-PAGE分型法分析山东半岛褶皱臂尾轮虫群体,获得8个多态微卫星。等位基因数2~4个;观测杂合度和期望杂合度范围分别为0.1471~0.6364和0.3139~0.6559;遗传偏离指数为-0.3624~0.05353;多态信息含量为0.2615~0.5841。无微卫星偏离哈温平衡,但有2个微卫星处于连锁不平衡。本研究筛选的8个微卫星为褶皱臂尾轮虫遗传多样性和种群结构分析提供了标记。  相似文献   

7.
为了探究Tc1/Mariner转座子超家族对褶皱臂尾轮虫(Brachionus plicatilis)基因组结构和基因表达调控的影响,本研究基于褶皱臂尾轮虫的基因组和转录组数据,对褶皱臂尾轮虫的重复序列进行了注释,并对褶皱臂尾轮虫的转座子的表达和其临近基因的表达进行了统计和富集,在基因上下游及内部区域富集到了10个转座...  相似文献   

8.
褶皱臂尾轮虫 (BrachionusplicatilisO F M櫣ller,以下简称Bp)和圆形臂尾轮虫(B rotundiformisTschugunoff,简称Br) (Segers,1 995)是轮虫门 (Rotifera)单卵巢纲(Monogononta)的两个海水种或半咸水种 ,过去曾分别被认为是褶皱臂尾轮虫的L型和S型品系 ,现统称为褶皱臂尾轮虫  相似文献   

9.
比较培养研究表明:钙质角刺藻(Chaetoceros calcitrans)和新月菱形藻小型变种(Nitzchia closterium foema minutissima)是墨吉对虾(Penaeus merguiensis)搔状幼体的良好饵料,亚心型扁藻(Platymonas subcordiformis)和小球藻(Chlorella sp.)则较次。钙质角刺藻的适宜投喂密度为1.5—5.0×10~4细胞/ml。褶皱臂尾轮虫(Brachionus plicatilis)和丰年虫(Artemia salina)无节约体都是ZⅢ-PI期幼体的良好饵料。实验中还分析了蛋白酶、脂肪酶、a-淀粉酶及纤维素酶的活性随墨言对虾幼体发育的变化及6种生物饵料的蛋白质、脂肪、淀粉和纤维素的含量。  相似文献   

10.
UV-B辐射增强对壶状臂尾轮虫摄食的影响   总被引:4,自引:0,他引:4  
研究了UV-B辐射条件下壶状臂尾轮虫(Brachionusurceus)对6株海洋微藻:小球藻(Chlorellasp.)、绿色巴夫藻(Pavlovauiridis)、扁藻(Tetraselmischuii)、球等鞭金藻8701(IsochrysisgalbanaPark8701)、牟氏角毛藻(Chaetocerosmuelleri)和小新月菱形藻(Nitzschiaclostertum)的室内摄食实验。结果表明,UV-B辐射增强对壶状臂尾轮虫的摄食有显著的抑制作用。与对照组相比,壶状臂尾轮虫对给定饵料单胞藻的滤水率和摄食率都随UV-B辐射剂量的增大而显著减小(P<0.05)。而且壶状臂尾轮虫对每一种饵料单胞藻的滤水率和摄食率是不相同的,这说明壶状臂尾轮虫对饵料单胞藻是有选择性的。  相似文献   

11.
海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明:土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。  相似文献   

12.
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14.
A set of 27 marine planktonic bacteria isolated from the polar regions was characterized by 16S rDNA sequencing and physiological and biochemical testing. More than half of these bacteria were positive for caseinase, gelatinase and 13-glucosidase, and could utilize glucose, maltose or malic acid as carbon source for cell growth. Twelve isolates expressed nitrate reduction activities. Except for one antarctic isolate BSwlO175 belonging to Actinobacteria phylum, these isolates were classified as γ-Proteobacteria, suggesting that γ-Proteobacteria dominated in cultivable marine bacterioplankton at both poles. Genus Pseudoalteromonas was the predominant group in the Chukchi Sea and the Bering Sea, and genus ShewaneUa dominated in cultivable bacterioplankton in the Prydz Bay. With sequence similarities above 97%, genus Psychrobacter was found at both poles. These 27 isolates were psychrotolerant, and significant 16S rDNA sequence similarities were found not only between arctic and antarctic marine bacteria ( 〉 99% ), but also between polar marine bacteria and bacteria from other aquatic environments ( ≥ 98.8% ), including temperate ocean, deep sea, pond and lake, suggesting that in the polar oceans less temperature-sensitive bacteria may be cosmopolitan and have a bipolar, even global, distribution at the species level.  相似文献   

15.
Sediment properties, such as water content and density, have been used to estimate the dry and wet weights, as well as the volume of sediment recovered and discharged, during benthic impact experiments conducted in the Pacific and Indian Oceans. The estimates show that the weights of dry (355-1332 t) and wet sediment (1651-4888 t) recovered during the experiments, are not only a function of the total duration and distance covered during the experiment, but also depend on water content and density of the sediment. Estimation of dry sediment and its volumetric ratio in the discharge, are key parameters for calculating the discharged volume. The estimated volume of wet sediment recovered (1427-4049 m 3 ) as well as discharged (2693-6951 m 3 ) during the experiments, provide important inputs to evaluate the sediment resettlement and migration. Using these estimates, the average depth of excavation on the seafloor, can also been calculated. However, the stages of sediment recovery and discharge are expressed differently in some of the experiments. In order to standardize these, different stages have been identified, and definitions of certain terms have been suggested, for use in the future. The methods of calculating different properties, as well as weight and volume of discharged sediment are described in the paper for use in other applications concerning deep-sea discharges.  相似文献   

16.
A vertically integrated model has been used to study the tidal circulation and currents in the Gulf of Kachchh along the west coast of India. The model is fully nonlinear and uses a semiexplicit finite difference scheme to solve the basic hydrodynamic equations on a staggered grid. The model is forced by prescribing the tides along the open boundary of the model domain. The flow is simulated both with and without the presence of the proposed tidal barrage across the Hansthal Creek in the Gulf of Kachchh. The results show a considerable change in the behavior of the tidal flow in the presence of the barrage.  相似文献   

17.
<正>The typhoon,as a mature tropical cyclone that develops in the western part of the North Pacific Ocean with high wind speed and heavy rainfall,is one of the most lethal and costly of natural disasters for the densely populated countries of East Asia.It can be easily detected by space-borne sensors operated at microwave,visible or infrared bands(Liu et al.,2014).Synthetic Aperture Radar(SAR)is  相似文献   

18.
本文介绍了用国产D401型螯合树脂分离富集海水中铜、铅、锌、镉、铁、锰等痕量元素,并用原子吸收光谱仪测定其含量的方法。讨论了各元素的分离条件选择及干扰元素的影响,并与溶剂萃取法的结果作了比较。各元素检测的定量下限为:铜0.5μg/L、铅0.1μg/L、锌1.0μg/L、镉0.01μg/L、铁2.0μg/L、锰2.0μg/L。方法精密度在4—8%之间,回收率为90—102%。  相似文献   

19.
Soil core samples fromRhizophora mangleL. andAvicennia schauerianaStapf & Leech forests from south-eastern Brazil were analysed for their total organic matter content and their sugars, amino acid and amino sugars composition. Organic carbon and nitrogen contents were higher inAvicenniathan inRhizophorasoils. The contribution of sugars and amino acids to the total organic carbon pool was constant with depth inRhizophorasoils whereas inAvicenniasoils it increased. Spectral distribution of sugars and amino acids showed a dominance of Ca-affine monomers, particularly acidic amino acids, and the sugar arabinose. Biogeochemical indicators derived from ratios of individual sugar and amino acid monomers confirm previous studies which showed that organic matter in both soils is mainly of mangrove origin. The results further suggest accumulation of organic matter inRhizophorasoils and a continuing degradation of organic matter inAvicenniasoils. The latter may thus release more nutrients to adjacent ecosystems thanRhizophorasoils.  相似文献   

20.
Orange roughy Hoplostethus atlanticus are unusual fish. They form dense aggregations that have fuelled lucrative fisheries at great depths (600–1 400 m), especially off Namibia, New Zealand and Australia. They are thought to be very long-lived (>100 years, maturity at 22 – 40 years), and to have exceptionally low natural mortality (M = 0.045–0.064 year?1) and slow growth rates (K = 0.055–0.070 year?1). In addition, they spawn large eggs and have low fecundity. These factors combine to make orange roughy highly susceptible to overfishing; most stocks are below 30% of pristine levels. Assessments are obtained from indices of catch rate and trawl, acoustic and egg surveys. Acoustic estimates are the most direct, but are confounded by the species' low target strength (?50 to ?53 dB)–attributable to the wax-filled swim bladder. Extracellular wax esters are stored in abundance and comprise mostly mono-unsaturated fatty acids, with low concentrations of the ω-3 fatty acid family. This unusual composition (resultant from the species' diet) ensures neutral buoyancy. Stock separation has been inferred mainly from biological studies, but genetic studies have also found differences among stocks within New Zealand and Australia. Deep-water habitat may be damaged by trawling operations and may take many years to recover, so in some quarters there is a call for a portion of suitable habitat to be set aside for preservation. Although Namibian orange roughy are shallower, smaller and younger than those in other stocks, the Namibian fishery sustained high catches for only a few years before quotas were reduced, from 12 000 to 1 875 tons. Three management lessons are suggested for developing orange roughy fisheries based on the Namibian experience: (1) imposition of catch limits during exploratory fishing; (2) starting the acoustic surveys earlier in the fishery, if possible; (3) greater reliance on trends in catch rate until a survey series has been established.  相似文献   

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