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1.
人工增殖放流是恢复鲎资源最有效、最迅速的方法, 而了解和掌握环境因子对中国鲎(Tachypleus tridentatus)幼鲎生长状况的影响规律, 进而选择适宜放流的时间和海区, 是保证人工放流得以成功的关键。本文在实验室条件下, 研究了不同盐度(5‰、10‰、15‰、20‰、25‰、30‰、35‰、40‰)对中国鲎幼鲎成活率、蜕壳率、蜕壳增重率、Na+-K+-ATP酶活性、免疫酶活性、抗氧化酶活性等的影响, 探讨了不同盐度水平下中国鲎幼鲎生长、蜕壳、渗透调节能力、机体免疫力和抗氧化能力等的变化。养殖试验持续56d, 结果表明: 不同盐度对中国鲎幼鲎的成活率、蜕壳率、二龄幼鲎均重及蜕壳增重率均有显著影响(P<0.05), 且均随盐度升高呈先升高后降低的趋势; 蜕壳率和蜕壳增重率与盐度的回归分析均表明, 中国鲎幼鲎蜕壳与生长的最适盐度分别为24.10‰和24.94‰; 一龄和二龄幼鲎的Na+-K+-ATP酶活性均随盐度的升高呈先显著升高后显著降低趋势(P<0.05); 35‰和40‰盐度试验组一龄幼鲎的酸性磷酸酶(acid phosphatase, ACP)活性显著高于其他试验组, 而5‰盐度试验组一龄幼鲎的碱性磷酸酶(alkaline phosphatase, AKP)活性显著低于25‰试验组(P<0.05) ; 盐度对二龄幼鲎的ACP、AKP和溶菌酶(lysozyme, LZM)活性均没有显著影响(P>0.05); 35‰和40‰试验组一龄幼鲎的过氧化氢酶(catalase, CAT)活性显著高于盐度较低试验组(P<0.05); 二龄幼鲎的谷胱甘肽过氧化物酶(glutathione peroxidase)活性随着盐度的升高而升高, 盐度10‰试验组显著低于30‰和40‰试验组(P<0.05)。研究结果显示盐度对中国鲎幼鲎生长、蜕壳、Na+-K+-ATP酶活性、免疫指标和抗氧化能力均有显著影响, 蜕壳最适宜的盐度在24‰~25‰左右, 盐度过高或过低都将引起幼鲎生长率和成活率降低, 渗透调节能力、免疫力和抗氧化力显著下降。 相似文献
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Ca2+, Mg2+对中国龙虾叶状幼体存活、变态的影响 总被引：1，自引：0，他引：1
龙虾是高级海产品,经济价值很高.龙虾的发育要经过叶状幼体、游龙虾幼体、稚龙虾和成体龙虾几个阶段.在龙虾幼体的培育中,叶状幼体生长、蜕皮、变态所需时间最长.影响叶状幼体存活、变态的因子较多,除了温度、盐度、光照以及铒料的质量、数量之外,还与海水中的矿物元素等有关.在矿物元素中Ca2+,Mg2+作用显得比较突出.龙虾蜕壳、生长与体内的Ca2+,Mg2+积累有关,Ca2+,Mg2+对龙虾幼体的营养物质和能量代谢极为重要.龙虾幼体在蜕皮生长的过程中需要足够的钙、镁来满足体壳(皮)的更新和机体的生长所需. 相似文献
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本文以人工配合饲料为对照组，4种添加剂为实验组，对中国龙虾进行50d的生长试验，结果表明：复合脱壳素（实验组1^#)效果最佳，其次分别是脱壳素（实验组2^#)、甲壳粉（实验组3^#)、喹乙醇（实验组4^#)和对照组，其增重率分别为：17.08、8.41%、7.62%、5.45%和4.21%；蜕壳率分别为58.33%、50.33%、33.33%、33.33%和33.33%；蜕壳后增重率为29.29%、16.90%、22.85%、16.43%和12.68%；饲料系数分别为7.57、7.11、7.92、11.00和14.21；对照组和实验组4^#存活率为91.67%，其余均为100%。整个试验过程龙虾生长良好。 相似文献
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研究了盐度(6、13、20、27和33)对拟穴青蟹(Scylla paramamosain)幼蟹生长发育和Na+/K+-ATP酶活性的影响。结果表明,盐度对拟穴青蟹幼蟹甲宽和体质量特定生长率、C3蜕壳间期、甲宽增量(C1至C2和C2至C3)及Na+/K+-ATP酶活性有显著影响(P<0.05),但对幼蟹存活率、C2蜕壳间期及C3至C4甲宽增量无显著影响(P>0.05)。盐度13处理组特定生长率最高、蜕壳间期最短,盐度6处理组特定生长率最低,但与盐度20、27和33处理组无显著差异(P>0.05),而盐度33处理组蜕壳间期最长;第一次蜕壳后盐度20处理组甲宽增量最大,后两次蜕壳盐度13处理组均是最大;盐度处理0.5、4、7和11 d时,Na+/K+-ATP酶活性分别表现为盐度6>13>20>27>33、6>13>27>20>33、6>13>20>27>33和6>13>33>20>27的趋势,低盐环境下Na+/K+-ATP酶活性的升高有助于拟穴青蟹幼蟹对低渗环境的适应。 相似文献
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盐度是影响对虾存活、生长的重要因子。对虾对盐度的适应除与温度、对盐度变化的适应时间、发音阶段、蜕壳期等因子有关外,还与个体大小密切相关。有关斑节对虾仔虾对盐度的适应已有许多报道,Cawthorne(1983)报道了第28天的仔虾对盐度的适应能力强于40K以后的仔虾;Chakraborti(1986)用1.0～1.2厘米仔虾为材料作了盐度变化对其存活率的影响试验;林美云(1982)也用头胸甲长0.53～0.74厘米(体长约1.5～ 相似文献
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为探究三疣梭子蟹"科甬1号"仔蟹最佳蜕壳环境条件,先采用单因素变量实验设计方法,选取温度、盐度、光照时长、p H和底质五种环境因素,分析其对"科甬1号"仔蟹蜕壳的影响。温度组设置17、20、23和26°C,盐度组设置10、15、25和35,光照时长设置0、12和24h光照组,p H组设置6.0、7.5、8.0、8.5和10.0,底质设置有沙和无沙组。实验结果表明,温度组20°C时仔蟹存活率和蜕壳率最高,但蜕壳所需时间最长,26°C时蜕壳起始最早,所需时间最短,但存活率较低;盐度组中,15和25仔蟹存活率和蜕壳率最高;p H组中,7.5、8.0和8.5仔蟹存活率和蜕壳率最高;有沙组仔蟹存活率显著高于无沙组;而光照时长实验组结果差异不显著(P0.05)。综上所述,得到单因素条件下"科甬1号"仔蟹最佳环境条件:温度20—23°C、盐度15—25、正常日周期光照、p H 7.5—8.5,有沙环境中。利用正交设计实验方法,研究温度、盐度、底质3个因素对"科甬1号"仔蟹蜕壳的影响,并构建多元线性回归模型。结果得到"科甬1号"仔蟹最佳环境条件:温度26°C、盐度25,需要有沙环境,并且拟合得到其日存活率线性回归模型以及日蜕壳率线性回归模型。 相似文献
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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
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温度、盐度和光照对一株有毒利玛原甲藻生长的影响研究 总被引：1，自引：0，他引：1
针对一株利玛原甲藻(Prorocentrum lima Dodge),应用小鼠生物测试法和高效液相色谱-质谱联用分析方法对其毒性和毒素成分进行了初步分析,并通过多因子实验,研究了温度、盐度和光照强度等环境因子对利玛原甲藻生长的影响.分析结果显示,这株利玛原甲藻能够产生大田软海绵酸(Okadaic acid,OA)和鳍藻毒素1(Dinophysistoxin 1,DTX1)等腹泻性贝-毒-(Diarrhetic Shellfish Poison,DSP).多因素方差分析结果表明,在实验条件范围内(温度为18、21和24℃;盐度为28、32和36;光照强度为2500、5 000和7 500 lx),利玛原甲藻的生长受盐度影响显著(P＜0.05),而温度和光照强度对利玛原甲藻的生长没有显著影响.温度和光照强度及温度和盐度之间的交互作用对利玛原甲藻的比增长率也有显著影响(P＜0.05).根据实验结果,这株利玛原甲藻生长的最适条件为:温度18℃,盐度28,光照强度7 500 lx. 相似文献
9.
盐度对波部东风螺幼虫存活、生长及变态的影响 总被引：13，自引：0，他引：13
采用突变和渐变两种实验方法检验了盐度对波部东风螺幼虫存活、生长和变态的影响。这两个实验，在盐度21．0－27．5的范围内，幼虫均有较高的存活率、变态率和较快的生长速度。其中，在盐度24．0处，幼虫的存活率和变态率都最高，生长速度也最大。不管盐度如何，幼虫较快的生长速度总是和自发变态前较短的浮游期联系的，尽管渐变盐度没能使幼虫的存活率、变态率、生长速度、变态个体的大小以及浮游期的长度得到显著的改变，却明显地加宽了幼虫存活和变态的盐度范围。渐变盐度的实验方法优于突变盐度的实验方法。 相似文献
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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
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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
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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
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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
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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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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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Oedometer tests have been carried out on 70 undisturbed surficial clays (at approximately 250 mm below the mudline), mostly collected by free-fall corers from sites widely scattered throughout the deep-sea North Atlantic. Acoustic measurements were also made, initially on contiguous samples and ultimately on the same sample using a geophysically instrumented oedometer which also collected electrical resistivity data. Apart from those quiescent areas below the carbonate compensation depth, such as north of the West Indies where very fine clays exist, most of the samples are silty clays whose geotechnical-geophysical properties are dependent on the type of clay minerals present (and their ability to take in moisture), the sand-size fraction, and the quantity of carbonate present. Thus the pure clays have high compressibilities which decrease on the addition of coarse particles, while the converse is true for the acoustic parameters, these increasing with the sand fraction. Using the notion of the intrinsic compression line for all samples, and comparison to it of the measured compression curves, it is clear that, contrary to some previously held ideas, most deep-sea clays are normally consolidated; the addition of carbonate has the effect of creating an open, stronger sediment skeleton. Interestingly, where information is available, the variation with depth of a sample's acoustic velocity follows the void ratio pressure relationship of the compression curve. This allows the construction of an in-situ sediment compression curve using the in-situ geophysical observations. 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