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1.
根据南方和北方海带夏苗培育采用苗帘苗绳差异,在山东烟台国家级海带良种场海带育苗基地进行两种夏苗培育工艺的实验研究。在同一个育苗车间内,利用种海带采集游孢子并附苗,跟踪观测维尼纶苗帘和棕绳苗帘对海带育苗期间配子体发育、孢子体(幼苗)生长的影响,并比较两种不同苗帘育苗成本差异。结果显示:相同育苗条件下,维尼纶苗帘采苗后,配子体发育速度、孢子体形成速度显著优于棕绳苗帘上的配子体和孢子体;转化孢子体后,在育苗第15~31天时间内,维尼纶苗帘海带幼苗相对生长速率(RGR)显著大于棕绳苗帘幼苗(P0.05);维尼纶苗帘幼苗经55天培育,幼苗平均长度长至1.53 cm±0.13 cm,达到出库下海暂养规格,此时棕绳帘幼苗平均长度约0.47 cm±0.03cm。至70天,棕绳苗帘幼苗平均长度约1.78 cm±0.19 cm,维尼纶绳苗帘幼苗平均长度达7.87 cm±1.35cm,显著大于棕绳苗帘幼苗。采用维尼纶苗帘育苗,每1m3育苗水体育苗量约为60万株,综合育苗成本约为23元/万株,采用棕绳苗帘育苗,每1m~3育苗水体育苗量约40万株,综合育苗成本约为31元/万株。综上所述,北方采用维尼纶帘进行海带育苗在生产上具有可行性,并且可降低生产成本约25.8%。  相似文献   

2.
厦门文昌鱼人工繁育批量生产技术研究   总被引:3,自引:0,他引:3  
周仁杰  方琦 《台湾海峡》2007,26(1):121-128
2005年5月21日至7月6日从厦门市翔安区欧厝附近海域采集文昌鱼亲体6批共计550余尾,移入室内进行强化培育.7月16日和17日夜间,培育的亲体自然排放精卵并受精,共获得受精卵125万粒.受精卵孵化获得浮游幼体115万尾,孵化率达92.0%.孵化的幼体经25d较高密度人工培育,获得99.2万尾体长0.31~0.72cm的文昌鱼苗及未成苗浮游幼体;分苗疏养后,又经28d继续培育,存活的幼体几乎全部潜入沙层中,最终获得体长0.55~1.30cm的厦门文昌鱼潜沙苗23.2万尾,其53d育苗成活率达20.7%.这是国内外首次人工培育获得成批量的文昌鱼增养殖苗种.进而于2005年11月6日向厦门文昌鱼自然保护区实施了国内外首次的文昌鱼资源人工增殖放流.  相似文献   

3.
为了促进大石花菜Gelidium pacificum Okam育苗的效果,本文就不同的切段密度对切段的再生、附着、切段苗的生长以及直立苗的形成与生长的影响,探索育苗适宜的切段密度。1材料与方法大石花菜采自浙江普陀山和朱家尖中低潮带石沼。种藻的暂养、切段制备、育苗及管理同文献[2]。在30cm×3cm的竹片上,分别放置0.3cm的切段15,30,45和60段,即,切段的密度分别为0.17,0.33,0.50和0.67段/cm2,进行室内育苗和海上培苗的试验。测定的指标及方法同文献[2]。室内育苗的…  相似文献   

4.
针对海带夏苗致病与育苗水系中细菌大量繁殖有密切的关系,于1984年在福建三沙海带育苗室同时从微生物、生理生态和培养技术三个方面对水系中微生物进行监控,具体步骤为:1.小心地抽出,古海况及气象条件不佳时,即停止抽水;2.育苗海水要经黑暗沉淀和过滤;3.种海带必须健康清洁,将首批放散的孢子水排掉不用,而以第二批孢子水采苗;4.育苗苗帘须经过严格漂洗和消毒。通过以上措施取得育苗的成功。  相似文献   

5.
花尾胡椒鲷的大规模生产性早繁育苗   总被引:1,自引:0,他引:1  
2003年2月28日至4月15日于湛江东海岛进行了花尾胡椒鲷(Plectorhinchuscinctus)大规模生产性人工早繁育苗的研究。研究选取网箱养殖的成熟健壮亲鱼,强化培养一段时间后,采用LRH-A2,HCG进行人工催产,自然受精后放在30m3的育苗池中培养15d,再转移到室外高位池中培养。育苗获得平均体长40mm的鱼苗33.3万尾,育苗成活率为12.8%。  相似文献   

6.
春季繁殖期两茬贻贝苗的培育   总被引:1,自引:0,他引:1  
七十年代以来,我国贻贝养殖如雨后春笋,蓬勃发展,针对苗源供应不足的情况,有关单位相继开展了开发自然苗场及人工育苗的研究。为了充分发挥育苗设施的作用,当前贻贝人工育苗一般是从三方面进行研究的:(1)提高单位育苗水体的产量;(2)增大海上养育幼苗的保苗效果;(3)争取一年培育多茬苗。对于培育多茬苗,过去我们已成功地培  相似文献   

7.
近些年有相当数量的正规对虾育苗厂在我国沿海各主要养殖地陆续兴建。舟山有近4万亩对虾面积,就有平均投资百万元左右的正规对虾育苗厂8家。继而由于对虾育苗的不稳定性,对虾养殖场分布的不均匀性,影响了部分虾塘对虾苗的及时放养。为了弥补这一局限,出现了一些群众性的土法上马的简易对虾育苗场。这种育苗场利用多种废弃水泥池,如报废的紫菜育苗池。闲置的水产盐制品加工池等,加以适当改造,改建成育苗池。具有因地制宜,投资少(一般6~7万元)设备简易等特点。有效地补充了正规育苗厂的某些不足;给一些附近偏僻虾场带来了方便;并随着科技人员下乡搞科技服务,使虾类育苗技术逐渐普及到群众,为推动对虾养殖业的蓬勃发展作出了一定贡献。  相似文献   

8.
海带人工育苗是发展我国海带养殖事业的一个重要环节。在人工培育海带幼苗过程中,时常出现烂苗或掉苗现象。多年来,这个问题在南方或北方都存在,严重时甚至可以使整个育苗工作陷入困境,给育苗和供苗工作带来严重威胁。过去,有关育苗单位力图从管理措施上严加控制。但由于对烂苗或掉苗的基本原因缺乏认识,工作难免盲目,预防效果也极不显著,至今尚未获得妥善解决办法。烂苗或掉苗现象,是一个复杂的问题。但  相似文献   

9.
山东省刺参增养殖技术发展现状   总被引:8,自引:0,他引:8  
刺参是我国传统的名贵海产品,具有很高的食用和药用价值,价格高、市场容量大.为开发近海这一资源,原农牧渔业部曾于80年代初组织全国刺参增养殖技术攻关并取得重大成果.大水体刺参人工育苗(0.5cm)技术突破3000头/M2以上,地播增殖也有创新技术,为刺参增养殖生产奠定了基础.此后的近20年来,广大渔民和科技工作者的生产实践和科学试验使这项技术不断丰富与完善.参苗育成量逐年增多,仅长岛县年培育量就达6000-8000万头,育苗水平也大有提高,不少场家已达4000-5000头/M2,而且苗种的规格质量也更高(体长1cm以上).增养殖方式也从单一的潮下带地播增殖发展为多种养殖技术.  相似文献   

10.
一向在餐桌上受人喜爱、味道鲜美、营养丰富的虾蛄,已由国家海洋局第一海洋研究所研究人工繁殖、育苗获得成功,育出虾蛄苗2万尾,为今后我国人工养殖虾蛄迈出了关键的一步。 虾蛄俗称虾爬子,又称东方虾蛄,属口足类甲壳动物。随着近年来对虾、扇贝养殖品种  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   

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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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