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1.
中华乌塘鳢(Bostrichthys sinensis) 和大弹涂鱼( Boleophthalmus pectinirostris) 成熟产卵过程中17a-羟基孕酮和前列腺素水平的研究 总被引：5，自引：2，他引：5
以酶联免疫吸附分析法测定了中华乌塘鳢和大弹涂鱼成熟产卵过程中卵巢液、精巢液、贮精囊液、雌鱼尿液和雄鱼尿液中的17α-羟基孕酮(17α-P)、前列腺素E2(PGE2)和前列腺素R2α(PGF2α)的含量。结果表明，中华乌塘鳢卵巢液中的17α-P和PGE，含量随着卵巢发育成熟而升高。性成熟前后卵巢液中的PGE，含量高于PGF2α。性成熟雄鱼尿液和贮精囊液中的PGE2含量显著高于精巢液或雌鱼尿液。性成熟前后雌鱼尿液中的17α-P、PGE2和PGF2α含量均显著高于卵巢液。性成熟和退化期雌鱼尿液中的PGE2含量明显高于PGF2α。性未成熟大弹涂鱼(第Ⅳ期)卵巢液中PGE2和PGF2α，含量极低；性成熟时(第V期)卵巢液中的PGE2、PGF2α和17α-P含量显著上升，PGF2α含量显著高于PGE2。 相似文献
2.
大弹涂鱼(Boleophthalmus pectinirostris)是盛产于我国东南沿海滩涂的两栖经济鱼类。分别用1,2,4μg/g的Aroclor 1254对生殖期雄性大弹涂鱼腹腔注射28 d后,检测大弹涂鱼精巢与储精囊的绝对与相对重量,并检测其精巢线粒体氧化水平、抗氧化酶活性与非酶类抗氧化剂含量。结果显示,1μg/g Aroclor1254剂量组中大弹涂鱼精巢、储精囊绝对重量与对照组均无显著差异(p=0.90),而较高剂量组(2,4μg/g Aroclor1254)上述指标均显著低于对照组(p0.05);相对重量指标中仅4μg/g Aroclor1254剂量组的储精囊相对重量显著低于对照组(p0.05)。此外,Aroclor1254使精巢抗氧化防御能力降低,三个处理组的SOD活性与GSH含量均比对照显著下降(p0.05),较高剂量组CAT,GPx,GR活性及Vit C含量也均显著低于对照(p0.05);而H2O2产量与脂质过氧化反应显著增加,1,2和4μg/g剂量组中MDA含量分别为对照组的1.12,1.52和1.80倍,H2O2含量分别为对照组的1.20,1.40和1.75倍,与Aroclor1254剂量呈现明显相关性。表明Aroclor1254可以诱导精巢线粒体的氧化应激对精巢产生毒性,影响雄性大弹涂鱼生殖机能。 相似文献
3.
以人工合成的17α-羟孕酮(17α-P)、17α,20β-双羟孕酮(17α,20β-P)、前列腺素E2(PGE2)和前列腺素F2α(PGF2α)作为性信息素,吊挂在陶瓷管道内诱发性成熟野生和养殖中华乌塘鳢产卵,以陶瓷管道产卵率、总产卵量和平均受精率为指标,比较了两者的产卵效应,测定了产卵水和生活水(未产卵水)中PGE2和PGF2α的含量以及性腺提取液中17α-P、PGE2和PGF2α的含量。结果表明,性信息素能明显提高诱发中华乌塘鳢的产卵效应。在同等实验条件下,诱发野生鱼的产卵效应优于养殖鱼。野生鱼和养殖鱼产卵水中的PGE2和PGF2α水平分别高于生活水中的,野生鱼和养殖鱼产卵水中的PGE2水平均极显著高于PGF2α(P<0.01)。PGE2在卵巢、精巢和贮精囊提取液中的含量,野生鱼均高于养殖鱼。 相似文献
4.
大弹涂鱼卵巢发育的组织学研究 总被引：1，自引：0，他引：1
对大弹涂鱼Ｂｏｌｅｏｐｈｔｈａｌｍｕｓｐｅｃｔｉｎｉｒｏｓｔｒｉｓ卵巢周年变化和卵母细胞发育规律进行研究，结果表明：深圳湾大弹涂鱼３月卵母细胞进入大生长期发育阶段，４—６月为繁殖盛期，７—８月为繁殖末期。１０月卵巢基本修整完毕，进人Ⅱ恢复期。精孔细胞单个，陀螺形，具微突假足，由滤泡膜细胞分化而成。卵母细胞膜单层，由具有辐射纹的放射带构成。滤泡膜细胞分泌而成的次级卯膜成为成熟卵子的附着丝。大弹涂鱼在一个生殖季节中只能产卵１次，属于一次性产卵类型。 相似文献
5.
人工管道诱导大弹涂鱼产卵研究 总被引：12，自引：0，他引：12
报道了人工制作的陶瓷管道诱导大弹涂鱼Boleophthalmus pectinirostris产卵的研究结果，未经激素催熟的亲鱼放入产卵池内7-12d未见产卵，经一次激素注射催熟的亲鱼放入产卵池内第3天开始酱产卵和受精，入池后5d未能产卵雌鱼的卵母细胞开始退化吸收，雌鱼不仅在管道内产卵，而且也将卵产在管道外，池底和池壁，产卵时间集中在下半夜的02：00-04：00，不同产卵池中管道的产卵率差别很大，卵子粘附在管道不同部位的数量和受精率均不相同，强迫配对的亲鱼虽有产卵，但卵子不受精。 相似文献
6.
目前关于青弹涂鱼（Scartelaos virids）的研究多数集中在胚胎和仔鱼发育等个体生物学研究上。本文研究广东省湛江海域中青弹涂鱼在性周期内卵母细胞的发育时相及卵巢结构的周年变化，揭示卵巢发育和卵母细胞的组织学发育规律。结果表明：湛江海域的青弹涂鱼卵母细胞在3月进入大生长期发育阶段，4—6月为繁殖盛期，7—8月为繁殖末期，10月卵巢基本修整完毕，进入Ⅱ恢复期。青弹涂鱼属于一次性产卵类型。在小生长期，卵核的体积较核质的体积增大快，核质比大；大生长期，随着卵黄物质的积累，卵母细胞体积快速增加，核质比下降。最后讨论青弹涂鱼卵膜结构及其生理机能，围核透明层，繁殖习性等问题。 相似文献
7.
大弹涂鱼卵巢发育的组织学研究 总被引：2，自引：0，他引：2
对大弹涂鱼Ｂｏｌｅｏｐｈｔｈａｌｍｕｓｐｅｃｔｉｎｉｒｏｓｔｒｉｓ卵巢周年变化和卵母细胞发育规律进行研究，结果表明：深圳湾大弹涂鱼３月卵母细胞进入大生长期发育段，４－６月为繁殖盛期，７－８月为繁殖末期。１０月卵巢基本修整完毕，进入Ⅱ＇恢复期，精孔细胞单个，陀螺形，具微突假足，由滤泡膜细胞分化而成，卵母细胞膜单层，由具有辐射纹的放射带构成。滤泡膜细胞分泌而成的次级卵膜成为成熟卵子的附着丝，大弹涂鱼在 相似文献
8.
黑斑口虾蛄(Oratosquilla Kempi Schmitt)配子发生的显微观察 总被引：1，自引：0，他引：1
观察黑斑口虾蛄Oratosquillakempi的精巢和卵巢 ,并对精、卵巢进行组织切片显微观察。结果表明 :黑斑口虾蛄的精巢由 1对很细的管状结构组成 ,精子发育可分为精原细胞、初级精母细胞、次级精母细胞、精子等期 ,精子圆球形 ,无鞭毛。卵巢分左、右两叶 ,对称且相互粘连。卵细胞为多黄卵 ,卵母细胞发育分为未发育期、卵黄形成前期、卵黄形成期和成熟期 4期 ;在卵黄形成前期形成大的生发泡。卵巢发育分为未发育期、发育早期、发育期、成熟前期、成熟期和产卵后期 6期。 相似文献
9.
大弹涂鱼室内人工繁殖和育苗技术研究 总被引：8，自引：0，他引：8
本文进行了大弹涂鱼室内人工繁殖和育苗研究.性激素注射雌性亲鱼864尾,雄性亲鱼846尾,以陶瓷管道诱导产卵和人工授精的方法获得受精卵,采用塑料箱和塑料桶两种容器孵化受精卵,比较了不同的仔稚鱼培育密度和培育方法与成活率的关系.研究结果表明,雌鱼的催熟率为40.0%～65.0%;管道产卵率为10.0%～26.0%,管道内卵子的平均受精率为60.0%～75.0%,人工授精卵平均受精率为45.0%～65.0%;管道内卵子在塑料箱内的孵化率为17.8%～28.0%,人工授精卵在塑料桶内的孵化率为38.5%～57.0%;共投放初孵仔鱼264000尾,经42～46d培育后变态为幼鱼,共培育出幼鱼31098尾,幼鱼平均全长为1.89cm,平均成活率为11.78%. 相似文献
10.
广西北部湾管角螺性腺发育与繁殖规律研究 总被引：1，自引：0，他引：1
《中国海洋大学学报(自然科学版)》2015,(11)
本文对广西北部湾海域管角螺(Hemifusus tuba)的生殖系统进行了解剖和观察,采用组织切片技术对其生殖腺发育和生殖细胞的发生过程进行研究。结果表明:广西北部湾管角螺为雌雄异体,雌雄比例接近1∶1。雄性生殖系统主要由精巢、贮精囊、前列腺、输精管和阴茎(阴茎囊和交接器)构成,精巢发育分为增殖期、生长期、成熟与排放期、退化期4个时期。雌性生殖系统由卵巢、输卵管、囊腺体(蛋白腺和缠卵腺)、生殖孔和腹足口组成,卵巢的发育分为增殖期、生长期、成熟与排放期、休止期4个时期。精细胞发生经过精原细胞、初级精母细胞、次级精母细胞、精细胞期和成熟精子期5个阶段。卵细胞发生经过卵原细胞、初级卵母细胞、次级卵母细胞、成熟卵子4个阶段。管角螺生殖腺在1周年内具有2个繁殖周期,且卵巢与精巢的周年变化规律相吻合。此外,观测的全部雌性个体除了雌性生殖系统外,还具有雄性生殖器官输精管和阴茎。广西北部湾管角螺雌性个体均存在性畸变现象,性畸变率为100%。 相似文献
11.
Chandralata Raghukumar G. Sheelu P. A. Loka Bharathi Shanta Nair C. Mohandass 《Marine Georesources & Geotechnology》2001,19(1):1-16
In order to assess the impact of deep-sea mining on the in situ benthic life, we measured the microbial standing stock and concentration of organic nutrients in the deep-sea sediments of the Central Indian Ocean Basin in the Indian pioneer area. Sediments were collected using box core and grab samples during September 1996. The total bacterial numbers ranged from 10 10 -10 11 cells per g -1 dry weight sediment. There was a marginal decrease in the number of bacteria from surface to 30 cm depth, though the subsurface section registered a higher number than did the surface. The highest numbers were encountered at depths of 4-8 cm. The retrievable number of bacteria were two orders less in comparison with the direct total counts of bacteria. An almost homogeneous distribution of bacteria, total organic carbon, living biomass, and lipids throughout the depth of cores indicates active microbial and benthic processes in the deep sea sediments. On the other hand, a uniform distribution of total counts of bacteria, carbohydrates, and total organic carbon in all the cores indicates their stable nature and suggests that they can serve as useful parameters for long-term monitoring of the area after the benthic disturbance. Further studies on temporal variability in this region would not only verify the observed norms of distribution of these variables but would also help to understand restabilization processes after the simulated benthic disturbance. 相似文献
12.
Derek V. Ellis 《Marine Georesources & Geotechnology》2001,19(1):51-63
This article reviews information recently available from existing marine and coastal mining for responses to environmental issues affecting marine mining at different depths. It is particularly but not exclusively concerned with those issues affecting seabed biodiversity impact and recovery. Much information has been gathered in the past 10 years from shallow mining operations for construction aggregate, diamonds, and gold, from coastal mines discharging tailings to shallow and deep water, and from experimental deep mining tests. The responses to issues identified are summarized in a series of eight tables intended to facilitate site-specific consideration. Since impacts can spread widely in the surface mixing layer SML, and can affect the biologically productive euphotic zone, the main issues considered arise from the depth of mining relative to the SML of the sea. Where mining is below the SML, the issue is whether it is environmentally better to bring the extraction products to the surface vessel for processing (and waste discharge), or to process the extraction products as much as possible on the seabed. Responses to the issues need to be sitespecific, and dependent on adequate preoperational environmental impact and recovery prediction. For deep tailings disposal from a surface vessel, there are four important environmental unknowns: (1) the possible growth of "marine snow" (bacterial flocs) utilizing the enormous quantities of fine tailings particles (hundreds or thousands of metric tons per day) as nuclei for growth, (2) the possibility that local keystone plankton and nekton species may migrate diurnally down to and beyond the depth of deep discharge and hence be subjected to tailings impact at depth, (3) the burrow-up capability of deep benthos and their ability to survive high rates of tailings deposition, and (4) the pattern and rate of dispersion of a tailings density current through the deep water column from discharge point to seabed. Actions to obtain relevant information in general and site-specifically are suggested. 相似文献
13.
G. Parthiban 《Marine Georesources & Geotechnology》2000,18(3):223-235
Particle fluxes were measured 7 m above the sea bottom during the predisturbance, disturbance, and postdisturbance periods by using time series sediment traps attached to seven deep-sea moorings deployed in the INDEX experiment site in the Central Indian Basin. The predisturbance particle fluxes varied between 22.3 to 55.1 mg m -2 day -1 . Increased and variable particle fluxes were recorded by the sediment traps during the disturbance period. The increase observed was 0.5 to 4 times more than the background predisturbance fluxes. The increases in particle fluxes (~4 times) recorded by the sediment trap located in the southwestern direction (DMS-1) were the greatest, which could be the result of preferential movement of resuspended particles generated during the deep-sea benthic disturbance along the general current direction prevailing in this area during the experimental period. Also, the traps located closer to the disturbance area recorded greater fluxes than did the traps far away, across the Deep Sea Sediment Resuspension System path. This variability in recorded particle fluxes by the traps around the disturbance area clearly indicates that physical characteristics such as grain size and density of the resuspended particles produced during the disturbance had an important effect on particle movement. The postdisturbance measurements during ~5 days showed a reduction in particle fluxes of ~50%, indicating rapid particle settlement. 相似文献
14.
Arne Schnack-Friedrichsen Angela M. Davis Jim D. Bennell Dei G. Huws 《Marine Georesources & Geotechnology》2001,19(4):221-243
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths. 相似文献
15.
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
16.
Geoacoustic Inversion via Genetic Algorithm and Its Application to Manganese Sediment Identification
An acoustic inversion method using a wide-band signal and two near field receivers is proposed and applied to multiple layered seabed models including a manganese sediment. The inversion problem can be formulated into a probabilistic model comprised of signals, a forward model, and additive noise. The forward model simulates wide-band signals, such as chirp signals, and is chosen to be the source-waveletconvolution plane wave modeling method. The wavelet matching technique, using weighted least-squares fitting, estimates the sediment sound-speed and thickness on which determination of the possible numerical ranges for a priori uniform distribution is based. The genetic algorithm is applied to a global optimization problem to find a maximum a posteriori solution for determined a priori search space. Here the object function is defined by an L 2 norm of the difference between measured and modeled signals. Not only the marginal pdf but also its statistics are calculated by numerical evaluation of integrals using the samples selected during importance sampling process of the genetic algorithm. 相似文献
17.
The advanced piston corer (APC) has been used by the Ocean Drilling Program since 1985 for recovering soft sediments from the ocean floor. The pullout force measured on extracting the core barrel from the sediment is shown to correlate with the average shear strength of the sediment core measured in the ship's laboratory. A simple rule of thumb is derived relating the shear strength of the sediment to the pullout force. Multiple APC holes at individual sites allow the consistency of the pullout measurements to be assessed. The effects of different operational procedures during APC coring are also explored. Although generally applicable, the correlation between pullout force and laboratory measurements of shear strength breaks down for some APC holes, possibly because of the disturbance of some sediment types during the APC coring process. A better understanding of the physical process of APC coring, and its effect on the properties of the sediment both inside and immediately outside the core barrel, would indicate what confidence can be put on the measurement of pullout force as a way of evaluating the in situ shear strength of deep sea sediments. 相似文献
18.
Shigehisa Nakamura 《Marine Geodesy》2000,23(1):55-61
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone. 相似文献
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