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1.
报道杜氏鰤(Seriola dumerili)人工苗养殖生物学特性及养殖技术研究结果。在海区水温6-30．5℃。海水盐度14．33，溶解氧6．5-7．3mg／L，pH7．5-8．1，水流为15-35cm／s的网箱中，杜氏鰤人工苗叉长40-50mm，体质量1．5-1．7g，经208d养殖，叉长达到330-388mm，体质量达到950-1400g，饲料系数为11，成活率为71．7％；养殖720d，体质量达4．5-6．5k，饲料系数为8；养殖l080d，体质量达7．5-11．5kg，饲料系数为7；养殖l440d，体质量达13．，15．5k异，饲料系数为6；养殖l800d，体质量达15．5-18．5kg，饲料系数为5。第4年性腺发育成熟，4-5月份，海上网箱人工催产，平均每尾雌鱼可产卵1．8kg左右。 相似文献
2.
将花尾胡椒鲷(Plectorbinchus cinctus)的受精卵在室内育苗池和室外大池不同环境下进行人工育苗比较试验，在26℃～28．8℃的水温条件下，室内培育盐度保持26左右，室外大池的盐度变动范围为26．2～22．9，经过36d的培育，结果显示：①在室内育苗池培育的鱼苗成活率最高为13．9％，最低为6．4％，平均为11．0％；室外培育的成活率仅为6％，室内培育相对室外培育的成活率增加45．5％。②室内培育的鱼苗平均体长为34．5mm，室外培育为52．1mm，室外培育相对室内培育鱼苗体长增加33．6％。③活力试验。室内培育的鱼苗成活率最高为94．8％，最低82．4％，平均为90．9％，而室外培育的鱼苗成活率则达到99．6％，室外培育相对室内培育鱼苗活力试验的成活率增加8．0％。因此，室内培育鱼苗的成活率相对较高，但生长缓慢，活力较差；室外培育鱼苗成活率相对较低，但生长快，活力强。 相似文献
3.
黑鲪生态生长效率周年变化的研究 总被引：3，自引：0，他引：3
于1983年12月-1984年5月和1990年6月-1991年1月以中国科学院海样研究所生物培育楼养殖黑为材料，进行黑周年的摄食-生长实验，以探讨其生态生长效率变化规律。结果表明，作为冷温性鱼，黑在4．0－27．3℃水温条件下都有摄食；平均日摄含量为2．4－10．0g，相对体重的百分比为1．1%-4.4%．单见，这二者的周年变化趋势基本一致；平均体重日增长量以4，6，7月和10－12月份较高。生态生长效率波动于6．5%-34．7%范围内，年平均为16．7％。 相似文献
4.
为了解潮间带沉积物中底栖微藻的现存状况，于2003年10月至2004年4月，分4次测定分析了青岛湾潮间带沉积物中的叶绿素a和脱镁叶绿酸含量。结果表明，0-2cm层沉积物中叶绿素a的含量在1．73-5．71μg/g，脱镁叶绿酸含量在0．02-1．89μg／g，2-5cm层沉积物中叶绿素a的含量在0．51-4．32μg/g，脱镁叶绿酸含量在0．12-1．58μg/g。随深度增加，叶绿素含量减少；叶绿素a是主要存在形式，脱镁叶绿酸含量占叶绿素a含量的10％-75％；同时分析了水质和沉积物粒度对叶绿素含量的影响，结果表明叶绿素的含量和组成比例与水质有关；粒度越细的沉积物，叶绿素含量较高而且稳定。 相似文献
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用8种保存方法对淡水和海水水样中四个氮磷营养盐（NH3-N、NO3—N、NO3-N、PO4—P）参数及总氮的稳定性进行了7d保存效果的比较研究。结果表明，淡水与海水氮磷营养盐的最佳保存方法与效果各不相同，但淡水和海水的总氮值在各种方法保存下均十分恒定。综合考虑有效性及可操作性后提出了5d内的短期保存技术：（1）海水水样用5‰氯仿4℃条件下保存，供NH3-N、NO2—N和N03-N三个营养盐的测定，用5‰甲醛4℃条件下保存供PO4-P测定；（2）淡水用5‰氯仿4℃条件下保存，供NH3-N测定，5‰甲醛4℃条件保存供NO2-N、NO3-N和PO4-P测定。 相似文献
7.
提高日本对虾人工育苗成活率的研究 总被引：3，自引：0，他引：3
通过日本对虾Penaeusjaponicus人工育苗中饵料配给、水质处理和控制,以及幼体病害防治的单因子和多因子正交试验及大面积生产验证,对提高日本对虾人工育苗成活率的几项关键措施进行了探讨。结果表明：（1）在Z期,添加螺旋藻Spiralsp.粉10g·（1．0×106尾·d）-1、光合细菌2ml·（m3·d）-1和Z3期添加卤虫Artemia无节幼体1-2个·ml-1,使Z1－M1期幼体的成活率提高10％-15％;（2）用36％甲醛0．065－0．13mmol·dm-3和光合细菌2ml·（m3·d）－1处理并改良育苗水质,以及在N期1次性加水75％,至M3期加满,P1-5期换水6％－10％,P6-10期换水15％－20％,用此方法控制育苗水质,作用显著;（3）用间投联用0．5g·（m3·d）－1抗菌素的方法预防幼体细菌病效果良好;（4）在10个总水体为543m3的育苗池中,共育出P8-10期的虾苗3．026×107尾,单位平均出苗量为5．5×104尾·m－3,N-P8-10期的成活率最高达65％,平均为54．6％。 相似文献
8.
采用单因子分析方法,在室内模拟设置10个温度梯度(6-36℃)、10个盐度梯度(4‰-40‰)和4种底质(细粉沙、细沙、粗沙、混合沙组)及3个厚度梯度(5、10、30mm),研究温度、盐度和底质对大竹蛏稚贝生长及存活的影响.结果表明:1)在盐度为21.4‰的条件下,大竹蛏稚贝存活及生长的适温范围为6-30℃,最适温度范围为21-30℃;15℃以上随温度升高日生长率逐渐增大,30℃个体日生长率为1.82%,21℃组成活率最高达88%.2)在温度为21.6-28.6℃条件下,大竹蛏稚贝存活及生长的盐度适宜范围为20‰-32‰,最适盐度范围为20‰-28‰;盐度20‰时成活率最大为85%,盐度24‰时个体日生长率最大为1.72%.3)大竹蛏稚贝对底质环境无明显的选择性,沙的粒径大小对稚贝成活率和日生长率均无显著影响(P＞0.05);但稚贝在不同厚度底质中的成活率和日生长率存在显著差异,10和30mm组的成活率和日生长率均显著高于5mm组的成活率和日生长率(P＜0.05). 相似文献
9.
采用室内模拟的方法，对盐度、饵料、底质和温度对硬壳蛤稚贝成活率和生长率的影响进行了研究。结果表明，硬壳蛤稚贝存活和生长的适宜盐度范围为18－42，最适盐度范围为24－36。从稚贝成活率看，几种单胞藻的饲育效果顺序为：等鞭金藻＞美国扁藻＞混合藻＞亚心形扁藻＞大溪等鞭金藻＞三角褐指藻＞小球藻＞中肋骨条藻；但从稚贝日生长率看，几种单胞藻的饲育效果顺序为：混合藻＞等鞭金藻＝美国扁藻＝亚心形扁藻＞大溪等鞭金藻＞三角褐指藻＞小球藻＞中肌骨条藻。硬壳蛤对底质环境有一定的选择性，稚贝在纯砂底质中的成活率和日生长率均高于在纯海泥底质中，但砂的粒径大小对稚贝成活率和日生长率没有明显影响。硬壳蛤稚贝具有很强的耐高温能力，在室内控温条件下，能够耐受30－35℃的高温，但在室外自然温度条件下，当温度为21．8－35．4℃（平均为30．1℃）时，稚贝成活率却很低，无砂情况下只有32％，有砂情况下为零。 相似文献
10.
本文系斜带髭鲷鱼苗室外水泥池不同生态系的育苗试验．在育苗前的“养水”期 间,1号池接入小球藻、微绿球藻、扁藻、金藻、轮虫、桡足类、枝角类等生物饵料;2号 池仅接入小球藻、轮虫生物饵料．在水温19．1～23℃、比重1．019、pH值8．5的条件 下．2池鱼苗经100d的培育后,平均全长各为31mm和29mm,平均体重各为0．90g 和0．75g,成活率18．5％和10．1％．试验表明:在育苗前期,生物饵料的多样性有利于 开口仔鱼的摄食和营养,也利于鱼苗的生长发育和成活率的提高． 相似文献
11.
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
12.
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
13.
The effect of different fixation and storage protocols on the flow cytometric (FCM) simultaneous analysis of bacterioplankton and phytoplankton in coastal seawater samples (Mediterranean coastal lagoons) was investigated. FCM measurements (cell number, fluorescence and scatter characteristics) were obtained through DAPI staining. Three fixatives [glutaraldehyde (GA), formaldehyde (FA) and paraformaldehyde (PFA)] and two storage (3 months duration) methods (5 °C and −196 °C) were tested. Two dominant populations were detected in studied samples: bacteria and eukaryotic picophytoplankton. Adding fixatives (2% final concentration) appears necessary to obtain FCM exhaustive counts of all the bacteria and phytoplanktonic cells. This was related to the permeation effect of fixatives which allowed a better DAPI staining of the cells. Maximum fluorescence, i.e. optimal staining of the cells was obtained with FA or PFA, and significant lower fluorescences with GA. Fixed samples stored at 5 °C induced rapid cell loss. Only storage in liquid nitrogen of samples fixed with FA or PFA, allows mid-term (≥4 months) preservation of bacteria or picophytoplankton cell numbers, and limited evolution of DAPI-induced fluorescence and scatter characteristics. 相似文献
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《海洋学报(英文版)》2014,(9):F0003-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology, 相似文献
16.
The relationship between the flux of exotic benthic foraminiferal tests (i.e. tests which are supplied from open-sea sources alone) in a tidal inlet and that of bulk sediment was analysed, which can be expressed as two first-order linear equations. According to this relationship, in order to determine net sediment transport directions in the entrance, the test concentration in surficial sediments of the tidal basin can be compared against a ‘ critical level ’. The critical level is determined for the conditions that no net transport of bulk sediment is present within the entrance. If the observed concentration (averaged over the tidal basin) is higher than the simulated critical level, then the net sediment transport is directed to landward. This method is applied to the analysis of net sand transport at Christchurch Harbour, a tidal inlet system located in southern England. In this investigation, concentrations of exotic foraminiferal tests in the surficial sediments of the tidal basin and ebb tidal delta area were obtained from the analysis of sea-bed sediment samples. A series of probable critical levels were calculated based upon the data sets with regard to: (1) sediment discharge from the rivers; (2) magnitude of sediment discharge within the entrance during the ebb; (3) the test concentration outside the harbour; (4) the thickness of the moving layer; and (5) two parameters associated with dispersive processes. The results show that the concentration in the tidal basin sediment is higher than a number of simulated critical concentrations for representative cases. Consequently, the high level of the concentration of exotic benthic foraminiferal tests within the harbour should be explained as a result of landward net transport of sands within the entrance. 相似文献
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Rahul Sharma 《Marine Georesources & Geotechnology》2000,18(3):237-250
Observations on seafloor features from subbottom profiling and seabed photography data show that the undisturbed and natural conditions before the benthic disturbance undergo a substantial change after operation of the disturber. The effects can be seen in the form of deep trenches and grooves, formed by the action of the sleds and the pumping of the sediment along its path, as well as sediment piles on either side of the track. Biological traces such as fecal coils, casts, tubes, burrows, and trails get obliterated in the areas of disturbance and resedimentation. The smooth, uniform nature of the seafloor observed in predisturbance phase shows microtopographic changes in and around the disturbed area as a result of sediment excavation and resettlement. Vertical mixing as well as lateral transport of sediment alter the geological, biological, physical, and chemical conditions on the seafloor, which need to be monitored over time to assess the process and the time taken for restoration of environmental conditions. 相似文献
19.
Vance P. Vicente 《Marine Ecology》1989,10(2):179-191
Abstract. Long-term changes in the distributional patterns of commercial sponges ( Spongia spp. and Hippospongia spp.) within the West Indian Region indicates that: 1) commercial sponges had a widespread distribution throughout the whole West Indian Region and were ubiquitous in very shallow water until about the first half of the present century; 2) they were fished commercially not only in the traditional northern Caribbean sites (Florida, Gulf of Mexico, Bahamas) but also in the Greater ( e. g. , Hispaniola, Jamaica) and Lesser Antilles; and 3) they became extinct throughout most of the Lesser Antilles ( e. g. , Puerto Rico, Vieques, St. Thomas) sometime during the first half of this century. Mortalities of spongiids within the Antilles were found to differ from other marine mortalities in that: 1) species disappeared from a large region; 2) species vanished from different habitats and depths; and 3) natural populations never recovered. Species richness patterns suggest that commercial sponge genera ( Spongia and Hippospongia ) evolved under slightly cooler elimatic conditions than those found at present, and that these extinctions occurred as a direct or indirect effect of positive thermal anomalies in sea surface and atmospheric temperatures between 1900–1950. The concept that species diversity is stable on a regional scale is questioned. 相似文献
20.
The behaviour of an axially pre-loaded cylindrical member of an offshore structure, hit by a supply ship, has been investigated. The effects of axial pre-loading on the dynamic properties of members, the extent of damage and propagation of dynamic instability in the tubular members have also been investigated. Numerical models have been validated using available experimental data from the literature although these are mostly static with no pre-loading. Axial pre-loading was found to change the dynamic characteristics of some cylindrical members quite dramatically while it had no significant effect on others. The study examined whether there was any change in the behaviour between local and global modes when the loading was dynamic rather than static. The effect of damping on the dynamic instability of axially pre-loaded tubes under lateral dynamic loads was also studied. It was observed that for some geometries the quasi-static response can be used to define the boundary between bounded and unbounded dynamic responses. The main contribution of this study, compared with previous investigations reported in the literature, is that both pre-loading and dynamic effects have been included. 相似文献