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1.
实验室培养条件下,以新近孵化的卤虫(Artemiasalina)为食物,观测中华假磷虾(Pseudeuphau siasinica)雌性成体、仔虾和后期带叉幼体的碳氮收支.实验表明摄食率随食物浓度的升高呈线性提高,成体未出现饱和现象,反映其较高的摄食潜力.呼吸率(碳消耗率)与碳的摄食率及同化率分别呈线性正相关,比动力作用分别为9%~16%(摄入碳)和10%~17%(同化碳)以后期幼体更小.总氮排泄率与氮的摄食率及同化率也分别呈显著正相关,但仔虾例外.排粪率随摄食率升高而提高,从而同化效率与摄食率无关,介于0.84~0.95.食物氮源是中华假磷虾生长的主要限制因子,当摄食率低于10μg/(mg·d)(干重)时,假磷虾呈负生长.同化的氮以排泄消耗为主,体质生长次之,而蜕皮损失最少.同化的碳也以呼吸消耗和体质生长居多,但随摄食率有变化,蜕皮损失最少.在成熟雌体,估算的生殖生长(碳、氮)比蜕皮损失略高.净生长效率随摄食率(及同化率)升高而升高.达一定值后,仔虾和后期带叉幼体净生长效率略有下降.  相似文献   

2.
本研究建立中国刺参(♂)与日本红刺参(♀)杂交组合,通过对杂交子代的胚胎发育进行观察,详细描述其胚胎及幼体各个阶段的发育时序和形态特征,并比较在幼参培育期间杂交苗与中国刺参自交苗的生长和成活.结果表明,在20~22℃时,杂交子代发育至初耳幼体的时间为受精后24 h 38 min,发育至中耳幼体的时间为72 h 8 min,然后经过167h 8 min(约7d)发育至大耳幼体,到受精后第9天发育至樽形幼体.樽形幼体后期,纤毛环逐渐退化,浮游能力减弱,幼虫由浮游转至底栖生活.在幼参培育期间,受精后第38~51天,平均水温为25.2℃,杂交幼参的体重特定生长率(SGR)为2.58%,而自交幼参的SGR略高,为3.03%;从受精后第51~80天,平均水温达到27.17℃,杂交幼参的生长速度减慢,SGR减小至0.66%,但平均体质量明显增加,到第80天达到(0.34±0.035)g,而自交幼参活动能力减弱,摄食量明显减少,SGR减小至0.08%,生长近于停滞,到第80天平均体质量为(0.19±0.034)g.自交苗和杂交苗的成活率相差不显著,分别为82.2%和73.9%.这表明,在高温条件下杂交苗种比自交苗种生长优势明显.  相似文献   

3.
Abstract. Oysters Ostrea chilensis P hilippi 1845. from a 40-month-old cohort which came from the natural population of the Quempillen River Estuary Southern Chile, were used as parental stock n = 600 for a hatchery-produced cohort. At 12 months of age this cohort was analysed physiologically filtration rate, organic ingestion rate, absorption rate, assimilation efficiency, excretion rate, respiration rate and electrophoretically multilocus heterozygosity MLH using four loci: LAP, GPI, PGM, CA. Most physiological variables were positively correlated with dry weight P < 0.05. with the exception of assimilation efficiency, excretion size and net growth efficiency P > 0.05. Also. there was a positive correlation between body size, ingestion rate, absorption rate and net growth efficiency with MLH. Respiration rate and consequently energy losses were negatively correlated with MLH. The energetic efficiency product of a lower metabolic cost in the heterozygous individuals in this cohort is reflected in a higher net growth efficiency and a positive correlation between growth and MLH. The genetic basis for the relationship between metabolic parameters and heterozygosity can be due to an overdominance in this 12-month-old cohort.  相似文献   

4.
饵料浓度、温度对缢蛏能量代谢的影响   总被引:1,自引:0,他引:1  
本文以缢蛏(Sinonovacula constricta)为实验对象,使用实验室静水法,研究其在不同饵料浓度、温度梯度下的代谢情况,测定其摄食、呼吸、排粪、排泄等生理参数,并根据能量平衡原理估算了缢蛏的能量收支情况。结果表明:(1)缢蛏的摄食能、呼吸能、排泄能随饵料浓度的上升而增加;随着温度的变化,其摄食能呈峰值性改变,呼吸能和排泄能有缓慢增长趋势;(2)缢蛏从球等鞭金藻(Isochrysis sphaeric)中摄取的有机碳源主要通过呼吸代谢消耗,以粪便的形式排出,少部分随排泄代谢产物流出,余下的碳主要用作贝类自身的生长;(3)单因素方差分析表明,饵料浓度和温度均显著影响缢蛏的摄食率和耗氧率(P<0.05),温度为23℃时,缢蛏的摄食率和耗氧率在饵料浓度为3.0×105 cells/mL时达到最高;饵料浓度为3.0×105 cells/mL时,缢蛏的摄食率在23℃时达到最大值,而耗氧率和排氨率在31℃时达到最高。  相似文献   

5.
In a laboratory study of the ingestion and assimilation efficiency of larvae of Aeshna brevistyla Rambur and Hemicordulia australiae Rambur, ingestion was determined using Cerenkov radiation techniques and assimilation efficiency by a double‐labelled isotope technique. Of each prey item (Daphnia carinata), 30% was not ingested but lost as body fluids and as material within the alimentary canal of the prey. Assimilation efficiency was greater than 70% for both dragonfly species, which appears to be typical for most other invertebrate predators. The efficiency with which 12th‐15th‐instar Aeshna assimilated 14C did not increase with feeding rate, but Hemicordulia increased its efficiency through instars 12–14. When dragonfly larvae were pre‐fed before experimentation, assimilation efficiency decreased in both species.  相似文献   

6.
A shrimp-like crustacean of the coastal Zooplankton in the north-western Mediterranean Sea, the mysid Siriella armata, offers a test organism whose life cycle is entirely controllable under laboratory conditions. The effects of the heavy metal cadmium were studied on adults and juveniles cultured in the laboratory including acute toxicity, bioaccumulation and effects on growth, ingestion and moult cycle.  相似文献   

7.
By simulating an upwelling event in a laboratory microcosm, it was possible to promote the development of a natural and diverse planktonic community. An initial bacterioplankton community which developed in response to phytoplankton growth was dominated by small coccoid forms (0,14–0,2 μm3) of the genera Vibrio and Pseudomonas. This group was heavily exploited by the heterotrophic microflagellate Pseudobodo sp. (30 μm3). Later, the bacterioplankton community was dominated by large rods (0,7 μm3) which the flagellates seemed unable to exploit. A Lotka-Volterra predator-prey model fitted to the observed data indicated that the flagellates consumed 2,4 times their carbon body mass per day or 19 bacteria·flagellate?1·h?1 when prey were not limiting. Clearance rates were inversely proportional to prey density and ingestion rate, ranging from 2 × 10?3 to 20 × 10?3) μ?·flagellate?1·h?1. At typical field densities of bacteria and heterotrophic flagellates in the southern Benguela region, between 5 and 30 percent of the water column could be cleared per day. Specific growth rates of the flagellates were positively related to prey density, the maximal rate being 0,84 · d?1. Their initially faster growth rates allowed bacteria to increase in numbers despite predation. The growth yield of the flagellates (34–36 per cent) was also positively related to food density. Such low values suggest inefficient transfer of carbon to higher trophic orders but considerable nitrogen regeneration. Nitrogen excretion rates were approximately 6–7 μg N·mg dry weight?1·h?1, comparable to other flagellates but faster than ciliates. These rates are comparable with in situ measurements of NH+4-N excretion in pycnoclinal regions based on 15N isotope studies but are only about 20 per cent of measured rates in surface waters. This is interpreted to mean that, in pycnoclinal regions where the relative input of "new" nitrogen is high, there are few regenerative steps and the model describes them satisfactorily. In surface waters, observed rates of excretion can only be accounted for by many regenerative steps in a highly complex food chain in which the cumulative total of nitrogen excretion at each step amounts to that based on 15N labelling studies.  相似文献   

8.
光合细菌在海湾扇贝工厂化育苗生产中的应用研究   总被引:3,自引:0,他引:3  
1999年2月6日-4月10日,在青岛市崂山区海水育苗场80m3水体育苗池中,进行了几株光合细菌混合菌液作为海湾扇贝(Argopectonirradians)幼体及稚贝培育期水质净化剂及辅助饵料育苗生产试验,取得了显著效果。浮游幼体生长速度提高了18.3%,浮游期成活率提高20.3%,幼本提前30个小时出现眼点,稚贝变态率提高14.5%,产量提高94%。  相似文献   

9.
孙小真  刘志刚 《海洋科学》2010,34(10):62-67
对马氏珠母贝人工育苗换水、投附着基和饵料等关键环节进行了研究。结果表明:(1)不换水组的D形幼虫及壳顶幼虫的存活率,稚贝育成率以及D形幼虫、壳顶幼虫及稚贝壳长日生长率比换水组分别提高了15.3%、259.6%、186.5%、33.3%、34.2%、12.4%,且差异显著;(2)第1、2次投附着板组的稚贝壳长日生长率均比一次性投附着板组快,第3次投附着板组的壳长日生长率比其他所有组均慢,且差异均显著。多次投附着板组的同一批次稚贝均匀度均比一次性投附着板组好,且多次投附着板组比一次性投附着板组的稚贝育成率提高了32.5%,稚贝存活率提高了19.3%,采苗量提高了35%;(3)投喂虾塘水组稚贝存活率、育成率及壳长日生长率比投喂50%自溶酵母+50%小球藻组分别提高了28.1%、47.2%、35.9%,而投喂这两种不同饵料的稚贝阴干后的存活率差异不显著。研究表明,通过封闭不换水育苗、多次投附着板及投喂虾塘水中的生态饵料的方法可以高效地培育出健康的马氏珠母贝种苗。  相似文献   

10.
采用实验生态学方法研究了盐度对长江口缢蛏(Sinonovacula constricta)、河蚬(Corbicula fluminea)和光滑河蓝蛤(Potamocorbula laevis)滤水率、摄食率、同化率的影响。缢蛏组设6个盐度梯度(5,10,15,20,25,30),光滑河蓝蛤组设6个盐度梯度(5,10,15,20,25,30),河蚬组设6个盐度梯度(0,5,10,15,20,25),并测定了此3种滤食性贝类的生物学参数。结果显示,3种滤食性贝类的滤水率、摄食率和同化率随着盐度的上升而增加,当上升到一定盐度时达到峰值,然后随着盐度的升高而降低。盐度20时,缢蛏滤水率、摄食率和同化率达到峰值,分别为0.57L/h、5.38mg POM/h和0.72%。盐度10时,光滑河蓝蛤滤水率和同化率达到峰值,分别为0.46L/h和0.53%,摄食率在盐度15时达到峰值3.80mg POM/h。盐度5时河蚬滤水率和摄食率都达到峰值,分别为0.39 L/h和2.48 mg POM/h,同化率在盐度0时已达到峰值0.51%,并随盐度上升而下降。上述结果表明,盐度对3种滤食性贝类的3个摄食生理指标均有显著影响。  相似文献   

11.
火腿许水蚤对牙鲆仔稚鱼成活、生长及脂肪酸组成的影响   总被引:1,自引:0,他引:1  
在分析火腿许水蚤、卤虫无节幼体及轮虫这3种饵料生物脂肪酸组成的基础上,研究它们对牙鲆仔稚鱼存活、生长及脂肪酸组成的影响。结果表明:火腿许水蚤体内3种高度不饱和脂肪酸(ARA,EPA,DHA)总量为34.18%,明显高于其它2种动物的含量(卤虫无节幼体4.67%;小球藻强化轮虫9.39%)。投喂火腿许水蚤的仔鱼成活率极显著高于投喂卤虫无节幼体的仔鱼,与投喂混合饵料(卤虫无节幼体和火腿许水蚤按比例混合)的仔鱼存活率差异较显著;其全长增长倍数和增重倍数极显著高于投喂卤虫无节幼体和混合饵料的仔鱼。投喂火腿许水蚤的稚鱼成活率显著高于投喂卤虫无节幼体的稚鱼,与投喂混合饵料的稚鱼存活率差异不显著;其全长增长倍数和增重倍数极显著高于投喂卤虫无节幼体和混合饵料的稚鱼。投火腿许水蚤的仔稚鱼体内ARA、EPA、DHA的含量明显高于投喂混合饵料的和投喂卤虫无节幼体的仔稚鱼。  相似文献   

12.
饵料对花尾胡椒鲷仔稚鱼存活和生长的影响   总被引:7,自引:0,他引:7  
采用6种饵料分别投喂花尾胡椒鲷15日龄的仔鱼,15d后测定其成活率、全长、体重和捕苗操作后1d的死亡率。结果表明,投喂经自制的乳化鱼肝油强化的卤虫无节幼体或经自制的乳化鱼肝油强化的卤虫无节幼体加轮虫,花尾胡椒鲷仔稚鱼的成活率最高(86%~98%),生长快,捕苗操作后的死亡率低(0%~2.7%);投喂轮虫,花尾胡椒鲷仔稚鱼的成活率也较高(86%~88%),但捕苗操作后的死亡率较高(5.9%~9.1%),而生长最慢;投喂未经营养强化的卤虫无节幼体,仔稚鱼成活率最低(68%~78%),捕苗操作后的死亡率最高(48.3%~542%);投喂桡足类或桡足类加轮虫,成活率较高(78%~90%),捕苗操作后未发现死亡,但生长较慢。龙尾胡椒鲷15日龄仔鱼在停止投饵的情况下,4d即全部死亡。可以认为,经营养强化的卤虫无节幼体是花尾胡椒鲷仔稚鱼的最佳饵料,桡足类也是花尾胡椒鲷仔稚鱼的优质饵料。  相似文献   

13.
光周期对罗氏沼虾幼体生长及能量收支的影响   总被引:8,自引:0,他引:8  
于1995年2-5月,在L:D为4:20,8:16,12:12和24:0四种光周期条件下,用卤虫无节幼体作饵料增减罗氏沼虾幼体,测定其生长能量收支。结果表明,随着光照时间的延长幼体生长率增大,两者关系为:g=6.5245+3.6045lnT,但周期对幼体C,N含量和C:N值没有显著的影响;  相似文献   

14.
Growth and energy budget of marine amphipod juvenile Eogammarus possjeticus at different temperatures(20°C,24°C, 26°C, 28°C, 30°C, 32°C and 34°C) were investigated in this study. The results showed that the cumulative mortality rate increased significantly with rising temperature(p0.01), and exceeded 50% after 24 h when temperature was above 30°C. With the temperature increasing from 20°C to 26°C, the ingestion rate and absorption rate increased, but decreased significantly above 28°C(p0.01), indicating a decline in feeding ability at high temperatures. The specific growth rate increased with rising temperature, but decreased significantly(p0.01) after reaching the maximum value at 24°C. Similarly, the oxygen consumption and ammonia emission rates also showed a trend of first increase and then decrease. However, the O:N ratio decreased first and then increased with rising temperature, indicating that the energy demand of E. possjeticus juvenile transferred from metabolism of carbohydrate and lipid to protein. In the energy distribution of amphipods, the proportion of each energy is different. With rising temperature, the ratio of the energy deposited for growth accounted for ingested gross energy showing a trend of decrease, while the energy lost to respiration, ammonia excretion, and feces accounted for ingested gross energy being showed a trend of increase. It seemed that rising temperature increased the metabolism and energy consumption of the amphipods and, meanwhile, decreased the energy used for growth, which may be an important reason for the slow growth and small body size of the amphipods during the summer high-temperature period.  相似文献   

15.
分析了6个不同盐度和5个培育密度对中国刺参和日本红刺参(Apostichopus japonicus)杂交幼体的生长、存活和附着的影响。盐度实验结果显示,受精后第5天,30和35盐度组幼体成活率最高,分别为46.7%和40.0%。第2天至第5天,30盐度组耳状幼体的生长最快,到第5天平均体长达到最大值672.18μm;30盐度组的幼体附着率最高,为17.8%,而15和20盐度组中均没有出现附着的稚参。培育密度实验结果显示,受精后第5天,0.1个/mL密度组的幼体成活率最高,为66.7%,但各密度组的幼体成活率差异均不显著。0.5个/mL密度组幼体生长最快,到第10天达到最大平均体长,为801.38μm;在所有培育密度实验组中,0.5个/mL密度组的幼体附着率最高,为19.1%。因此,为实现单位水体的苗种产量最大化,刺参杂交幼体培育的最佳盐度为30,最适宜的培育密度为0.5个/mL。  相似文献   

16.
《Oceanologica Acta》1998,21(3):485-494
Release of amino acids was examined in the laboratory in the form of dissolved primary amine (DPA) by two marine planktonic protozoa (the oligotrichous ciliate, Strombidium sulcatum and the aplastidic flagellate Pseudobodo sp.) grazing on bacteria. DPA release rates were high (19–25 × 10−6 and 1.8–2.3 × 10−6 μmol DPA cell−1 h−1 for flagellates and ciliates, respectively) during the exponential phase, when the ingestion rates were maximum. Release rates were lower during the other growth phases. The release of DPA accounted for 10 % (flagellates) and 16 % (ciliates) of the total nitrogen ingested. Our data suggest that the release of DPA by protozoa could play an important role in supporting bacterial and consequently autotrophic pico- and nanoplankton growth, especially in oligotrophic waters, where the release of phytoplanktonic dissolved organic matter is low.  相似文献   

17.
Abstract. The ingestion of carnivores and omnivores was determined during the investigation of higher trophic levels in a North Adriatic benthic community. The ingestion rate was calculated from respiration data using a respiration-production equation and an assumed assimilation efficiency. In the case of the starfish Astropecten aranciacus the ingestion rate obtained by this indirect method was in good agreement with the ingestion rate calculated directly from gut contents, taking the retaining period of food items in the gut into consideration. These results are compared to previously published ingestion rates. The influence of A aranciacus on the community is briefly discussed.  相似文献   

18.
The biomass, elemental composition, and rates of ingestion and excretion by macrozoo‐plankon associated with the upwelling plume off the north‐west coast of the South Island, New Zealand, were investigated in March‐April 1983. Ingestion and excretion rates of the major zoo‐plankton species were combined with abundance data to determine the spatial and temporal variability which may influence phytoplankton dynamics in the plume system. Zooplankton biomass near Cape Kahurangi was dominated by small copepods like Acartia ensifera (up to 60%). In the South Tar‐anaki Bight, larval and adult forms of the euphau‐siid Nyctiphanes australis commonly contributed up to 60% of biomass. However, the carbon ingestion and ammonia excretion patterns of N. australis were spatially displaced from those of the total zooplankton community in the South Taranaki Bight because of higher weight‐specific metabolic rates for the smaller copepods. Close to the focus of the upwelling near the Kahurangi Shoals, grazing pressure on the phytoplankton was high, but as the upwelled water was advected into the Taranaki Bight, carbon production exceeded utilisation by zooplankton. Relatively high rates of ammonia excretion were also associated with peak zooplankton biomass near the Kahurangi Shoals and in the eastern Taranaki Bight.  相似文献   

19.
海水温度和盐度对泥蚶幼虫和稚贝生长及存活的影响   总被引:24,自引:0,他引:24  
1996~1997和1999年在浙江省乐清市东发水产育苗场和福建省宁德市四海水产育苗场分别研究了海水温度和盐度对泥蚶浮游幼虫和稚贝生长及存活的影响,结果表明,泥蚶浮游幼虫的适宜温度为25~33℃,最适生长温度为28~30℃.稚贝的适宜温度为15~35℃,最适生长温度为25~30℃.浮游幼虫的适宜盐度为16.54~30.02,最适生长盐度为1654~23.38;稚贝的适宜盐度为10.01~30.02,最适生长盐度为10.01~23.38.泥蚶幼虫和稚贝对高温和低盐海水有较强的适应能力,这与它们夏季的繁殖期和自然分布于内湾河口区是相适应的.  相似文献   

20.
A carbon flux study was carried out off the coast of Morocco, at 31°N, in a region characterized by the presence of a persistent cyclonic eddy. Two short-term (4 and 3 day) deployments of free-floating sediment traps were combined with water column sampling and rate process measurements as the ship followed the traps. For a period of 36 h between trap deployments, a hydrographic section was run along 31°30'N as part of a larger scale survey being carried out simultaneously on the R.V. A. von Humboldt. The first trap deployment was near the eastern margin of the eddy and the traps moved to the north and west in a frontal jet associated with its northern boundary. After the second deployment, which was at the recovery point of the first, the traps moved to the west and then to the southwest. Throughout the study, chlorophyll concentrations varied between 27 and 125 mg m−2 (0–100 m), with highest concentrations in the upwelled water nearest the coast and in upwelled water generated within the cyclonic eddy. Particulate organic carbon (POC) and particulate organic nitrogen (PON) concentrations were relatively uniform (13.6±1.8 and 1.63±28 g m−2 with phytoplankton carbon accounting for 16–85% of total POC. Bacterial carbon was 5% of total POC and mesozooplankton carbon concentrations were equivalent to 9% of total POC. Microzooplankton biomass was not assessed but POC:PON ratios in the water column were often high, suggesting there was sometimes a large detrital component in the POC. Primary production rates varied between 1.0 and 2.5 g C m−2 day−1. Bacterial consumption accounted for 50% of primary production. Metabolic rates suggested that copepods were ingesting more than 0.4 g C m−2 day−1. while filtration rates suggested that ingestion of phytoplankton carbon was only 0.2 g C m−2day−1, even when phytoplankton constituted 85% of the POC. f-ratios (based on uptake rates for 15N-nitrate and ammonia) were between 0.1 and 0.4, and excretion by mesozooplankton could account for 40% of the daily ammonium uptake by phytoplankton. HPLC pigment analysis showed that when chlorophyll biomass was high, diatoms were dominant, whereas when it was low, small prymnesiophytes, chlorophytes and diatoms were all important. The composition of the fluoresecent pigments in material in the sediment traps indicated that intact phytoplankton and copepod faecal pellets were the main sources but the relative rates of sedimentation of pigment, POC and PON for the two trapping periods did not reflect differences that were observed in the overlying water column. This was likely to be the result of spatial heterogeneity and strong horizontal currents heterogeneity and strong horizontal currents within the euphotic zone. Thus, material collected at 100 m probably did not originate in the water column immediately overlying the traps and trapping efficiencies might also have been variable.  相似文献   

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