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1.
1.巨藻夏孢子体海上暂养以1~2米水层生长最快。2.在自然海区,巨藻配子体发育适宜水温为13~15℃,培育水层以当时透明度的平均值为宜,水温偏低,(6.0℃以下)发育缓慢。在同一水温条件下,配子体发育快慢取决于培育水层的适宜与否。3.在秋、冬及春季都可进行人工采孢子,由于季节不同透明度变化很大,秋季采孢子以深水层(8~10米)萌发率最低,甚至全部死亡。春季则相反,浅水层(6米以上)几乎全部死亡。4.自然海区培育巨藻幼苗,采孢子时期以10月中旬为宜,这时的水温、透明度均有利于巨藻幼苗的发生和生长。附着基质以竹条和石块最佳。  相似文献   

2.
采用叶绿素荧光技术,以光系统Ⅱ最大荧光产量(Fv/Fm)为指标,结合形态显微观察,研究了GeO2在海带幼孢子体培育过程中菱形藻污染的抑制效应。结果表明,1)对于菱形藻,当GeO2浓度在5mg/L以上时,对其Fv/Fm值有显著影响,达到或超过15mg/L时菱形藻趋于死亡。2)对于海带幼孢子体,GeO2浓度在20mg/L以上时,对其Fv/Fm值有显著影响,达到或超过30mg/L时其趋于死亡。3)对于受到菱形藻污染的海带幼孢子体,GeO2浓度在15mg/L以上时对其Fv/Fm值有显著影响,达到或超过20mg/L时其趋于死亡。综合来看,当GeO2浓度为5~15mg/L时,菱形藻光合作用受到较强的抑制,而对海带幼孢子体影响不大。  相似文献   

3.
“海天1号”海带是南方耐高温品种与北方高产品种杂交后,经过几代选育获得的海带新品系,具有产量高、耐高温、成熟稍早等特点(暂命名为“海天l号”海带).为探究“海天1号”海带幼孢子体在不同环境因子下的生理适应性,设置了温度、光强及营养盐3个单因素实验,利用液相氧电极技术研究其对“海天l号”海带幼孢子体(1-2 cm)表观光合速率(Pn)和呼吸耗氧速率(R)的影响,并测定相对生长速率(Relative growth rate,RGR).结果显示:(1)温度为14℃、光强为80 μmolphotons/(m2.s)、氮营养盐为6 mg/L(N/P=10∶1,下同)环境下,幼孢子体的RGR和Pn均较大.在温度为22℃、光强为1 00 μmol photons/(m2·s)、氮营养盐浓度为10 mg/L条件下,R最强.(2) 22℃组的幼孢子体生长受到抑制,其RGR显著低于14℃组(P<0.05).20 μmol photons/(m2·s)与80 μmolphotons/(m2·s)光强组的RGR存在显著性差异(P<0.05).单因素方差分析显示,5个营养盐浓度组之间幼孢子体的RGR无显著性差异(P>0.05).(3)随着温度、光强、营养盐浓度增加,幼孢子体的Pn呈先上升后下降的趋势,14℃组Pn显著高于其他温度组,氮营养盐浓度4 mg/L和6 mg/L组的Pn显著高于2、8和10 mg/L组(P<0.05).在本实验条件下,R和Pn呈负相关.(4)光强对幼孢子体P/R(总光合速率/呼吸耗氧速率)的影响较小,温度和营养盐浓度对其影响较大.正交实验结果显示,适宜“海天1号”海带幼孢子体培养的条件为光强50 μmol photons/(m2·s)、温度16℃、氮营养盐浓度5 mg/L.  相似文献   

4.
为了从生理生态学角度解答温度和光照对海带孢子体生长过程的影响,探索海带孢子体对温度和光环境的生理响应机制,实验在测定养殖海域海带孢子体生长参数的基础上,设定了6、10、14和18°C 4个水温梯度的海带孢子体暂养实验,以及它们在0、25、70、133、230、317、421、582、786μmol photons/(m2·s) 9个光合有效辐射(PAR)梯度下的光合活性荧光参数测定。结果显示:①在6°C水温条件下,海带孢子体荧光参数Fv/Fm和Fv/F0最大,分别为0.71和2.40;在18°C水温条件下,其Fv/Fm和Fv/F0最小,分别为0.65和1.85;②暂养海带孢子体的光化学淬灭(qP)和非光化学淬灭(qN或NPQ)在18°C水温条件下达到最大,分别为0.92和3.29;③海带孢子体的快速光曲线随着光合有效辐射(PAR)的增强呈现先上升后下降的趋势;④海域养殖海带孢子体的最大叶长增长速率、叶宽增长速率和干重增重率分别为1.34 cm/d、0.33 cm/d和1.01 g/d。研究表明,海带孢子体干重生长率变化与不同水温条件下的快速光曲线变化一致,高温抑制了海带孢子体光合效率;当环境光合有效辐射大于样品光饱和点(Em)后,海带孢子体相对电子传递速率下降,光合作用受到抑制。  相似文献   

5.
通过设置培养液的不同盐度,在实验室条件下检验了笼目海带(Saccharina sculpera)在不同盐度的培养液中配子体生长发育情况。结果显示,在盐度20~30的条件下,笼目海带配子体大部分(60%~80%)进入了生殖生长状态,且其中50%以上为多细胞孢子体;在盐度35的条件下,大部分(80%~90%)笼目海带配子体维持在营养生长状态,虽然有小部分(7.30%)配子体进入了生殖生长状态,但生殖生长明显滞后于盐度20~30处理组。在盐度为40和45的培养条件下,所有海带配子体维持在营养生长状态。根据试验结果,建议将笼目海带配子体育苗的盐度保持在20~30。  相似文献   

6.
2010年,作者在辽东半岛成功进行了裙带菜室内常温全人工育苗大规模生产试验,并全程进行了光照强度、温度和配子体发育相关性的研究。研究表明,采用双高光期(≥50μmolphotons/m2·s)调控配子体的生长和发育可达到理想效果。从采苗至度夏前,采用高光照使配子体充分完成营养生长;从度夏结束至幼苗出库前,同样采用高光照,使配子体快速发育形成孢子体并迅速生长。现场观察表明,只要光照强度逾越了诱导发育的阈值,裙带菜配子体在24℃仍然能够正常发育并形成孢子体;幼孢子体能够耐受24~26℃的高温,但是最适生长温度为20~22℃;孢子体越小,耐受高温能力越强。在24~26℃的高温条件下,幼孢子体生长缓慢,较大个体会出现尖端溃烂缺失的现象。在整个育苗过程中,根据温度变化和配子体的显微观察结果因地制宜地对光线进行实时调整。出库前培育的苗帘在幼苗密度、大小和健康方面均达到商业化栽培的要求。  相似文献   

7.
本研究主要从生产应用角度出发,在配子体克隆一次附苗的基础上进行二次附苗实验,系统探讨了海带配子体克隆二次附苗、育苗各环节的关键技术,结果显示1.25g/帘为最佳附苗密度;当幼孢子体普遍达到0.3~0.5mm时为最适宜起始洗刷时间,0.05MPa的压力为最佳起始洗刷压力;沉降式附苗法为最适宜附苗法;细胞最优过滤孔径为38μm。配子体克隆二次附苗幼苗发育速度快于孢子体附苗和克隆一次附苗,从而可大大节约生产成本。  相似文献   

8.
长期以来,在人工低温培育海带夏苗中,病烂甚多。其中以育苗前期的配子体死亡和小孢子体畸形(即变形烂)危害最大。病烂表现为配子体转化时细胞壁增厚,原生质外移,被粘液包围,进而空壳死亡,接着就是刚转化的小孢子体空壳,细胞膨大或排列不齐,发育畸形,而烂掉。这种病烂严重地影响了出苗质量和数量,  相似文献   

9.
"海天1号"海带是南方耐高温品种与北方高产品种杂交后,经过几代选育获得的海带新品系,具有产量高、耐高温、成熟稍早等特点(暂命名为"海天1号"海带)。为探究"海天1号"海带幼孢子体在不同环境因子下的生理适应性,设置了温度、光强及营养盐3个单因素实验,利用液相氧电极技术研究其对"海天1号"海带幼孢子体(1–2 cm)表观光合速率(Pn)和呼吸耗氧速率(R)的影响,并测定相对生长速率(Relative growth rate,RGR)。结果显示:(1)温度为14℃、光强为80μmol photons/(m~2·s)、氮营养盐为6 mg/L(N/P=10∶1,下同)环境下,幼孢子体的RGR和P_n均较大。在温度为22℃、光强为100μmol photons/(m~2·s)、氮营养盐浓度为10 mg/L条件下,R最强。(2)22℃组的幼孢子体生长受到抑制,其RGR显著低于14℃组(P0.05)。20μmol photons/(m~2·s)与80μmol photons/(m~2·s)光强组的RGR存在显著性差异(P0.05)。单因素方差分析显示,5个营养盐浓度组之间幼孢子体的RGR无显著性差异(P0.05)。(3)随着温度、光强、营养盐浓度增加,幼孢子体的P_n呈先上升后下降的趋势,14℃组P_n显著高于其他温度组,氮营养盐浓度4 mg/L和6 mg/L组的P_n显著高于2、8和10 mg/L组(P0.05)。在本实验条件下,R和P_n呈负相关。(4)光强对幼孢子体P/R(总光合速率/呼吸耗氧速率)的影响较小,温度和营养盐浓度对其影响较大。正交实验结果显示,适宜"海天1号"海带幼孢子体培养的条件为光强50μmol photons/(m~2·s)、温度16℃、氮营养盐浓度5 mg/L。  相似文献   

10.
通过设置不同的光照强度和光照周期,在实验室条件下检测了笼目海带(Kjellmaniella crassifolia Miyabe)配子体的发育情况。结果显示:光照强度及光照周期均对笼目海带配子体的发育率有显著的影响(P0.05)。结果表明:1)在光照强度条件不同、其他培养条件相同的情况下,经过4周的发育,5~80μmol·m~(-2)s~(-1)条件下大部分配子体进入了生殖生长状态,发育率为60%~80%,其中20~40μmol·m~(-2)s~(-1)光照强度条件下生殖生长明显快于其他组。2)在光周期不同、其他培养条件相同的情况下,培养第12~25天时,20L∶4D条件下发育率为6.68%~69.87%,发育率与16L∶8D实验组差异不显著,但显著大于其余组。培养第32天,光照时间最长的处理组即20L∶4D的发育率(74.54%)最高,且孢子体细胞列数最多。本研究为笼目海带配子体规模化扩增及育苗提供了数据参考。  相似文献   

11.
In northern Japan, the early production of high-quality specimens of kelps Undaria pinnatifida prior to the outbreak of pinhole disease is needed. To address this need, we tested the effect of nitrate fertilization of gametophytes on the growth and maturation of sporophytes using experimental and control gametophytes derived from sporophytes cultivated in Matsushima Bay, northern Honshu, Japan. From mid-August to October 2008, experimental gametophytes were cultured on a rope indoors at a nitrate concentration of 1 mg/L at the optimal seawater temperature of 20 °C, whereas control gametophytes were cultured without the addition of nitrate in normal seawater at an average temperature of 23.5 °C during this period in the past 30 years. Next, the seedlings were cultivated in Matsushima Bay until March 2009. For the experimental kelps, the total length, stipe length, stipe width, sporophyll length, sporophyll width, and dry weight of the blade, midrib, and sporophyll increased significantly from December to January compared to those of control kelps. Matured sporophylls of the experimental kelps were more than those of the control kelps from early December to late January. Significant higher photosynthesis occurred at seawater temperatures of 10 and 15 °C, as well as higher uptake rates of NO3–N of the experimental kelps in December and January. These results show that nitrate fertilization of the gametophytes makes it possible to harvest the high-priced blade, midrib, and sporophyll in January, which is earlier than the traditional harvest date.  相似文献   

12.
Larvae and early postlarvae of the ocean quahog, Arctica islandica, were reared under experimental hatchery conditions. Mature eggs were stripped from ripe adults and exposed to a dilute solution of ammonium hydroxide for various lengths of time prior to addition of stripped sperm. The larval clams were reared through settlement and metamorphosis using the Wells-Glancy (centrifuged, incubated seawater) method of algal culture and/or modifications of standard hatchery techniques developed by Loosanoff and Davis. Experimental cultures were maintained at various temperatures ranging from 8.5° to 14.5°C. At temperatures of approximately 13°C, the minimum time to settlement was 32 days, while settlement was not observed in a culture maintained between 8.5° and 10.0°C until approximately 55 days after fertilization. Larval growth rates were significantly lower in the culture maintained at 8.5–10.0°C than in cultures maintained at 11.0–14.5°C. An optical micrograph sequence of larval stages from the straight-hinge stage through metamorphosis is presented to facilitate identification of Arctica islandica specimens isolated from plankton samples. While various workers have reported exceedingly low growth rates of juvenile and adult Arctica, growth rates of larval Arctica appear to be fairly “typical” of rates encountered within the class Bivalvia.  相似文献   

13.
Photosynthetic activity of Zostera japonica seedlings was measured using a gas volumeter at 0 and 6 days in culture under eight light (0–800 μmol photons/m2/s) and ten water temperature conditions (5–35°C). Seedlings from Ago Bay, Mie Prefecture were cultured in incubators accurately controlled at each test temperature for 1 week. After 1 week, maximum gross photosynthesis (P maxg) appeared at 29°C and most seedlings cultured at 30–35°C bleached and withered. At the same time, the light compensation point (I c) increased only at 30°C during the culture period. As a result, the upper critical water temperature for survival was 29°C in Z. japonica seedlings, which agrees well with that for the southern boundary of Z. japonica around Japanese coast. It is necessary to monitor this species around this boundary as a bio-indicator for seawater warming.  相似文献   

14.
Groups of Arctic charr, Salvelinus alpinus (L.), originating from an anadromous stock, were transferred directly from freshwater to seawater (35 S), from freshwater to brackish water (20 S), or were gradually adapted to seawater over a period of 10 days. A control group was kept in freshwater. Feed intake and growth were then monitored during the following 59 days. Two experiments were carried out, one during winter (December–January) and the other during summer (June–July). Water temperature was maintained at 8 C. All fish had been held under natural photoperiod and temperature conditions from the end of the first feeding period (mid-April) until the experiments were carried out. Rates of growth did not differ between the groups of charr held in fresh- and brackish water, but growth of these groups was better than that of fish reared in seawater. Relationships between individual feed intake (FI) and individual specific growth rates (SGR), within groups were expressed as: ln (SGR+1) = a + ln (FI+1), and regression lines were compared using analysis of covariance. In winter, the regression line for fish transferred directly to seawater had a significantly steeper slope, and a lower elevation, than the lines for fish transferred to brackish water or held in freshwater. Fish transferred gradually to seawater had an intermediate position. In summer, the regressions for all groups were parallel with intercepts in the seawater groups being significantly lower than in the freshwater group. This indicates that the gross feed conversion efficiency (FCE) in Arctic charr was lower in seawater than in freshwater. The results are discussed in relation to digestion, gut function and osmoregulation. yc]Keywords xc]Arctic charr (Salvelinus alpinus (L.)) xc]Feed utilization xc]Salinity xc]Season  相似文献   

15.
Seta  Tomofumi  Kurashima  Akira 《Fisheries Science》2021,87(3):365-370

The amphipod Sunamphitoe namhaensis grazes on seedlings of Sargassum horneri in culture. To exterminate S. namhaensis, we immersed them in seawater with dissolved carbon dioxide—a treatment used previously to remove copepods in cultures of abalone and sea cucumber. Experiments were conducted under different CO2 (aq) concentrations and for different lengths of time. Amphipod mortality was 100% following immersion in CO2 seawater with a CO2 (aq) concentration of 26,262 µmol/kg (pH 5.0) for 60 min. When algal seedlings were immersed in CO2 seawater under these same conditions, their survival rate and growth were not affected.

  相似文献   

16.
The purpose of the current study was to examine seasonal changes in seawater tolerance and growth performance of anadromous Arctic charr (Salvelinus alpinus L.) held at the same temperature (8°C) during winter and summer. Charr (20–27 cm), previously reared in freshwater under natural photoperiod, were transferred either directly (DT) from freshwater to seawater (35 ppt), from freshwater to brackish water (20 ppt), or were gradually adapted (GT) to seawater over a period of 10 days. Control fish were held in freshwater. Feed intake and osmoregulatory ability were then monitored on three occasions during the following 59 days. Two experiments were carried out, one during winter (December–January) and the other during summer (June–July). In both experiments fish mortality was low. Plasma osmolalities recorded in fish transferred to seawater were within normal ranges, but osmolalities on day 10, were significantly lower in summer (313 mOsm/kg (DT), 328 mOsm/kg (GT)) than in winter (323 mOsm/kg (DT), 352 mOsm/kg (GT)). In winter, feed intake and growth rates were high in fish kept in fresh and brackish water, but charr transferred directly to seawater ate little and lost weight. Fish that were gradually adapted to seawater occupied an intermediate position. During summer the observed differences in feed intake were small and all fish had relatively high growth rates. These results suggest that Arctic charr display seasonal changes in feed intake and growth performance that parallel seasonal changes in hypoosmoregulatory capacity. The ability to survive and hypoosmoregulate in full strength seawater does not, however, seem to be a particularly good indicator of successful seawater adaptation with respect to the ability to display high rates of feed intake and growth. During winter, a gradual transfer to seawater appeared to lead to improved feeding and growth compared to direct transfer.  相似文献   

17.
Mariculture of the economically important seaweed will likely be affected by the combined conditions of ocean acidification that resulting from increasing CO2 rising and decreased light levels, especially under high culture intensity and high biomass accumulation. To examine this coupling effect on the photosynthetic performance of Sargassum fusiforme seedlings, we cultured seedlings of this alga under different light and CO2 levels. Under low light conditions, elevated CO2 significantly decreased the photosynthesis of S. fusiforme seedlings, including a decreased photosynthetic electron transport rate. Seedlings grown under the low light intensity exhibited higher photosynthetic rates and compensation irradiance, and displayed higher photosynthetic pigment contents and light absorption than seedlings grown under high light intensity, providing strong evidence of photosynthetic acclimation to low light. However, the captured light and energy were insufficient to support photosynthesis in acidified seawater regardless of increased dissolved inorganic carbon, resulting in declined carbohydrate and biomass accumulation. This indicated that S. fusiforme photosynthesis was more sensitive to acidified seawater in its early growth stage, and strongly affected by light intensity. Future research should evaluate the practical manipulation of biomass accumulation and mariculture densities during the early culture period at the CO2 level predicted for the end of the century.  相似文献   

18.
Global warming increases seawater temperature, causing high temperature stress to marine organisms, including algae. This study aimed to explore the global proteomic response of Sargassum fusiforme under high temperature stress. Sargassum fusiforme seedlings were cultured in natural seawater for 24 hr and subjected to different temperatures (22°C, control group; 27°C and 32°C, high temperature stress group) for 1, 3, 5 and 7 days. Changes in their membrane lipid peroxidation after high temperature stress were investigated. Proteomic changes in the air bladders of S. fusiforme were analysed using isobaric tags for relative and absolute quantification, along with liquid chromatography–tandem mass spectrometry. Data were analysed using bioinformatics methods. Results showed that high temperature stress destroyed the cell membrane of the air bladders. Further, 28 and 53 differentially expressed proteins (DEPs) were found in the 27°C and 32°C treatment groups respectively. These DEPs were mainly involved in glycolysis, single‐organism catabolism, purine nucleoside diphosphate metabolism and carbohydrate catabolism. In addition, DEPs were significantly enriched in 10 pathways, such as glycolytic process, biosynthesis of antibiotics, ribosome, biosynthesis of secondary metabolites and biosynthesis of amino acids. Proteomics analyses indicated that proteins associated with synthesis, folding, degradation, photosynthesis and energy and carbohydrate metabolism are differentially expressed under high temperature stress and normal conditions.  相似文献   

19.
根据生态调查和筏式育苗效果的比较,采取了调低海水比重,每十天浸泡苗帘一次的方法清除杂藻。海水比重调节幅度在1.021-1.016之间,逐步降低海水比重浸泡苗帘,清除杂藻和各种动物幼虫,使江蓠育苗取得了成功。  相似文献   

20.
大菱鲆"温室大棚+深井海水"工厂化养殖模式   总被引:22,自引:12,他引:22  
大菱鲆Turbot(Scophthalmus maximus)的引进一方面为我国北方沿海工厂化养鱼增加了一个新的品种,另一方面又创立了“温室大棚+深井海水”工厂化养殖的新模式,大大丰富了工厂化养鱼的内容,有效的推动了我国海水养殖“第四次浪潮”的形成与发展。本文综述了大菱鲆温室大棚式工厂化养殖模式的养殖技术,以促进大菱鲆养殖业的健康、持续、稳定发展。  相似文献   

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