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1.
于1986年4月至1987年8月间研究了厦门港真刺唇角水蚤(Labidoceracuchaeta Giesbrecht)的生殖率,结果表明,在充足饵料条件下,相对产卵率与产卵雌体体长无关,与温度成正相关,与实验温度的关系有季节性的变化,分析10个月海区温度接近于实验温度的资料得到产卵率(F,卵/?/d)与温度(T,℃)和雌体碳重(Wc,μg C)的关系式:F=0.0637(T-7)~(0.7445)·Wc,总产卵量与体长成正相关,但与温度关系较复杂,在海区温度范围孵化率与温度无关,终年处于较高水平(58~94%,平均81%)。  相似文献   

2.
厦门港中华哲水蚤产卵量的初步研究   总被引:4,自引:2,他引:2  
在实验室条件下研究了厦门港中华哲水蚤(Calanus sinicus Brodsky)雌性成体的产卵量。结果如下:哲水蚤产卵量有显著的季节变化。每雌体平均产卵量和产卵个体百分数有三次高峰,分别出现在12—1月,3—4月和5月中旬;环境中铒料数量多寡、温度高低对哲水蚤的产卵量有显著影响。哲水蚤产卵的适宜铒料密度范围为2—8×10~4细胞/毫升(中肋骨条藻,三角褐指藻和盐藻的密度混合饵料);适宜水温范围应为10—20℃。  相似文献   

3.
在静水实验条件下,研究了不同饵料种类和浓度对太平洋真宽水蚤存活率、产粪数和产卵量的影响。结果表明:在食物碳含量为1.0 mg C/L的条件下,不同饵料投喂后,太平洋真宽水蚤的存活率、产粪数和产卵量有明显的差异(P0.05)。投喂亚心形扁藻、中肋骨条藻和三角褐指藻的存活率高于球等鞭金藻和小球藻(P0.05);投喂中肋骨条藻的产粪数明显高于投喂其他4种单胞藻的产粪数(P0.05);投喂亚心形扁藻和中肋骨条藻的产卵量明显高于小球藻(P0.05),其他饵料种类的产卵量无显著差异(P0.05)。实验进一步研究了不同浓度亚心形扁藻和中肋骨条藻对太平洋真宽水蚤生物学的影响,结果表明:不同浓度的亚心形扁藻对太平洋真宽水蚤的产卵量无显著影响(P0.05);不同浓度的中肋骨条藻对太平洋真宽水蚤的存活率、产粪数和产卵量差异性显著,且随着浓度的升高其存活率、产粪数和产卵量逐渐减少(P0.05)。投喂亚心形扁藻和中肋骨条藻饵料浓度为2.0 mg C/L时效果最好,表明此浓度条件下的亚心形扁藻和中肋骨条藻是太平洋真宽水蚤相对适宜的饵料,可为人工培养太平洋真宽水蚤作为水产活体生物饵料奠定基础。  相似文献   

4.
厦门港西海域冬季微型浮游动物在碳循环中的作用   总被引:3,自引:0,他引:3  
于2004年2月在厦门港宝珠屿利用稀释法和饵料浓度差减法培养实验,同步研究了微型浮游动物对浮游植物的摄食压力和对一种优势桡足类瘦尾胸刺水蚤(C en tropages tenuirem isThompson et Scott)的饵料贡献.结果表明,微型浮游动物对浮游植物现存量的摄食压力为38%,对初级生产力的摄食压力为63%;瘦尾胸刺水蚤对微型浮游动物纤毛虫和对浮游植物的清滤率分别为3.08 mL.ind-1.h-1和0.31mL.ind-1.h-1,摄食率分别为0.44μg.ind-1.d-1和0.24μg.ind-1.d-1.纤毛虫对此种桡足类的饵料贡献比为65%~95%.由此可见,微型浮游动物在冬季厦门海域的海洋生态系统中,对浮游植物的生产和归宿起着十分重要的调控作用,在浮游植物和桡足类之间起着重要的营养连接作用.  相似文献   

5.
真刺唇角水蚤摄食率的季节变化   总被引:1,自引:1,他引:1  
研究了厦门港真刺唇角水蚤(Labidocera euchaeta)成体在5个实验温度下(10℃,15℃,20℃,25℃和 30℃)个体摄食率(I)和相对摄食率(R)的季节变化及其影响因素。雌、雄两性成体I的年平均变化范围分别为:4.8~30.2和2.9一13.9μgC/cop·d;R 则分别为6.87~40.17和 3.02~33.33%DW/d。I和 R均有显著的季节变化,而且都同时受到海区水温、实验温度(t,℃)和体重(DW,μg)的交互影响。厦门港真刺唇角水蚤成体的摄食模型为I=0.540 t+0.070 DW-8.506(r=0.690,n=250)。  相似文献   

6.
厦门海域真刺唇角水蚤mtCOI序列分析   总被引:1,自引:1,他引:0  
采用PCR扩增、克隆和序列测定等技术对厦门海域真刺唇角水蚤(Labidocera euchaetaGiesbrecht)线粒体细胞色素氧化酶I亚基基因(mitochondrial COI,mtCOI)进行了初步研究,得到3个雌性个体的mtCOI基因片段序列,序列的长度为709 bp,其A,T,C,G平均含量分别为23%、37%、15%和25%.三条核苷酸序列经比较后,得到其遗传相似性(i-dentity)为99.29%,共有15个差异位点,核苷酸差异均为颠换(transversion)类型.比较了厦门海域真刺唇角水蚤与GenBank数据库中的角水蚤科(Pontellidae)6个种的mtDNA COI基因片段序列(索引号AY145428、AY145429、AB206443、AB206444、AB206445、AB206446),其同源性为87.34%.文中讨论了上述7种桡足类的系统发生关系.  相似文献   

7.
以浮游桡足类刺尾纺锤水蚤(Acartia spinicauda)对海洋原甲藻(Prorocentrum micans)的摄食实验表明,摄食率随着饵料密度增高而增大。在水温20℃时,最大摄食潜力约为33000细胞/个·天,夜间摄食力显著大于白昼,混合饵料实验中,刺尾纺锤水蚤表现出较强的择食倾向。由实验结果推导出摄食经验公式为:1=33 000(1-e~(-0.4x~2))。  相似文献   

8.
几种环境因子对太平洋哲镖水蚤清滤率和摄食率的影响   总被引:7,自引:1,他引:6  
本文用放射性同位素~(32)P和~(35)S标志饵料生物——中肋骨条藻(Skeletonema costatum)来研究几种环境因子(饵料密度、饵料‘年龄’(藻龄)、温度、光度)对太平洋哲镖水蚤(Calanus paci-ficus)清滤率和摄食率的影响.研究结果表明:(1)清滤率在高密度(>3.O×10~4个细胞/毫升)饵料溶液中,几乎随饵料密度的增高而按比例地下降;但在低密度饵料溶液中,清滤率虽有所提高,但绝对摄食量却是下降的.(2)哲镖水蚤对骨条藻的吸收率是很高的,通常为50—90%(平均80%左右),吸收率与藻龄有密切关系:当以生长良好的骨条藻(培养3—4天的藻液)为饵料,吸收率达80%以上;但以‘衰老’的藻液(培养6—7天)为饵料时,吸收率仅50%左右.(3)在10—20℃范围内,摄食率随温度上升而增加.超过20℃以后,摄食率即下降.(4)摄食率在黑暗中最高.在室内人工光照下,摄食率随光照强度的增加而下降.  相似文献   

9.
厦门几种海洋浮游桡足类的食性与饵料成分的初步研究   总被引:4,自引:0,他引:4  
厦门10种常见浮游桡足类的食性可分为下列三类: 1.素食性:包括太平洋哲镖水蚤,小型拟哲镖水蚤,针刺拟哲镖水蚤,敏哲镖水蚤和尖宽镖水蚤.它们的饵料成分基本上反映了海区中浮游植物的种类组成情况,对饵料的选择性不大.素食者的口部附肢具有发达的刚毛,其摆动产生了捕食涡流。第二小颚伸向前方,共羽状刚毛形成密微的过渡纲,大颚咀嚼缘齿较多。呈臼齿状,具发达的硅质齿冠,用以磨碎硅藻的外壳. 2.肉食性:包括精致真刺镖水蚤和特氏歪镖水蚤.主要捕食小型桡足类.但饵料成份有显著两性差异.肉食者口部附肢的刚毛较少.第二小颚或颚足强壮,具长刺,是强有力的捕食器官,大颚缘齿少,尖锐,呈犬齿状,且无齿冠.但雄性真刺镖水蚤几不捕食,口部附肢退化. 3. 杂食性:这类动物又可分为二群:(1)以素食性为主的有瘦尾刺镖水蚤和太平洋纺锤镖水蚤.它们也以硅藻为主要饵料,但含较多的碎屑.共口部附肢兼备素、肉食性的特点.如大颚齿部分有齿冠.但较尖锐.第二小颚基肢是过滤器.内肢刚毛稍呈爪状,以适捕食.(2)以肉食性为主的真刺髻角镖水蛋的饵料成分有季节变化.它的口部附肢和歪镖水蚤较为相似,但第二小颚基肢是过滤器. 桡足类粪块长度随饵料成分而不同,素食者的粪块最长,杂食者次之,肉食者最短.饵料不同,粪块颜色也有差异。  相似文献   

10.
在实验室培养条件下测定厦门海区三种歪水蚤的产卵率表明,右突歪水蚤最高,特氏歪水蚤次之,而钳形歪水蚤最低。右突歪水蚤的产卵率取决于温度的变化,且具显著的季节差异,其最大潜在产卵率与海区水温的变化呈线性相关;但特氏歪水蚤产卵率的季节变化及其温度效应不甚显著。这在维持种群数量上,可能具有一定的意义。实验还表明,捕食率也影响了特氏歪水蚤的产卵率,但随温度而有变化。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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