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1.
Growth rate in a population of the freshwater crayfish,Paranephrops planifrons white 总被引：1，自引：1，他引：0
C. L. Hopkins 《新西兰海洋与淡水研究杂志》2013,47(4):464-474
Observations on growth increments at moult in a population of freshwater crayfish, Paranephrops planifrons, were made from periodic recaptures of marked animals. The growth increment increased with increasing size of crayfish up to about 20 mm carapace length (65 mm total length) after which a slight decrease was evident. By analysis of the size distributions in samples taken at different times of year it was found that four to five year classes were normally present. Growth of these age components could be followed through consecutive samples. Mean size at leaving the parent in December was 3.5 mm, after one year 11.4–11.8 mm, after two years 18.2–19.3 mm, after three years 22.1–23.8 mm, and after four years 26.7–29.6 mm, all sizes quoted as carapace lengths. After sexual maturity growth in the females was less than in the males. The number of moults completed by each year class was found by relating data on growth increment per moult to growth shown in consecutive quantitative samples. In the first year of life nine moults were completed, in the second year three moults, in the third year two moults, and in the fourth one moult. Independent data on moult frequency recorded from marked crayfish agreed well with these figures. 相似文献
2.
《Journal of Sea Research》2010,63(4):229-237
Length growth in relation to water temperature was studied for Crangon crangon (L.) from two populations at the northern and southern edges of its distributional range to determine whether counter-gradient growth compensation occurs. In crustaceans, growth rate depends on the time between moulting events (intermoult period) and the size increase at moult (moult increment). In this study, the period between moults was shorter at higher temperature, ranging respectively from about 11 days at 25 °C to 27 days at 10 °C at southern edge, and from 10 to 24 days at the same temperatures at the northern edge. Moult increment showed a large variability, from 1.5 to 2.7 mm with no clear trend with temperature at the northern edge; and decreasing from about 2.7 mm at 10 °C to about 1.5 mm at 25 °C at the southern edge. As a result, the temperature effect on the overall growth rate differed between shrimps from the north and those from the south, suggesting counter-gradient growth compensation. At the northern edge, mean growth increased from about 0.12 mm d− 1 at 10 °C to about 0.23 mm d− 1 at 25 °C, while at the southern edge, growth was lower, about 0.08 mm d− 1 at 10 °C and increased to about 0.16 mm d− 1 at 25 °C. Maximum observed growth rates of shrimps from the north were also higher and ranged from 0.17 mm d− 1 at 10 °C to 0.89 mm d− 1 at 25 °C, while shrimps from the south grew at a maximum of 0.08 to 0.75 mm d− 1 respectively at 15 and 20 °C. Sex and size differences were also found, with males growing slower than females and at a decreasing growth rate with increasing size. Implications for the brown shrimp's life cycle are discussed. 相似文献
3.
The objective of this study was to examine the eff ects of temperature and light intensity on growth of female gametophytes of Eisenia bicyclis and Ecklonia cava and responses of these female gametophytes to Fe addition and daylength. Female gametophytes of each species were cultured at four temperatures (10, 15, 20, and 25°C) and under a combination of four light intensities (10, 20, 40, and 80 μmol photons/(m^2 ·s)) with two temperatures (15 and 20°C for E i . bicyclis;20 and 25°C for E c . cava ) to clarify their optimal growth conditions. Growth and maturation of female gametophytes of these two species under a combination of five Fe-EDTA concentrations (0, 1, 2, 4, and 8 μmol/L) and three daylengths (10, 12, and 14 h) were also examined. The growth of E i . bicyclis gametophyte was maximal at approximately 15–20°C, 20 μmol photons/(m^2 ·s), Fe-EDTA concentration of 8 μmol/L and daylengths of 12–14 h. While E c . c ava gametophytes showed optimal growth at approximately 20–25°C, 20 μmol photons/(m^2 ·s), Fe- EDTA concentration of 8 μmol/L and daylength of 14 h. Maturation of gametophytes was enhanced at Fe-EDTA concentration of 4 μmol/L for E i . bicyclis and at 2 μmol/L for E c . c ava . In conclusion, optimal growth temperatures and Fe-EDTA concentrations for maturation of E i . bicyclis and E c . c ava gametophytes were diff erent. Higher optimal growth temperature for E c . c ava gametophytes may contribute to its wider geographical distribution compared to E i . bicyclis which has restricted habitats in Korea. This suggests that addition of Fe ion could be used to recover beds of these two species in barren grounds of Korea. 相似文献
4.
Barrier and compensation layers in the East China Sea 总被引：1，自引：0，他引：1
Climatology of the isothermal layer depth （ILD） and the mixed layer depth （MLD） has been produced from in-situ temperaturesalinity observations in the East China Sea （ECS） since 1925. The methods applied on the global are used to compute the ILD and the MLD in the ECS with a temperature criterion AT=0. 8 ℃ for the ILD, and a density criterion with a threshold △σθ corresponding to fixed △T=0. 8 ℃ for the MLD, respectively. With the derived climatology ILD and MLD, the monthly variations of the barrier layer （BL） and the compensation layer （CL） in the ECS are analyzed. The BL mainly exists in the shallow water region of the ECS during April-June with thickness larger than 15 m. From December to next March, the area along the shelf break from northeast of Taiwan Island to the northeast ECS is characterized by the CL. Two kinds of main temperature - salinity structures of the CL in this area are given. 相似文献
5.
温度和盐度对几种大型海藻生长率和NH4-N吸收的影响 总被引：19，自引：3，他引：19
温度和盐度对细基江蓠繁枝变型(Gracilaria tenuistipitata var.liui)、孔石莼(Ulva pertusa)和蜈蚣藻(Grateloupia filicina)生长率及细基江蓠繁枝变型NH4-N吸收的影响进行了实验研究.结果表明,温度和盐度对上述3种海藻生长率及NH4-N吸收均有显著影响.3种海藻的生长适宜温度和盐度范围分别为细基江蓠繁枝变型20～30℃,15～30,孔石莼15～25℃,15～40,蜈蚣藻20～25℃,25～35;最大日特定生长率(SGR)分别为8.66%,12.28%,2.24%;N饥饿细基江蓠繁枝变型对NH4-N的吸收存在短期的快吸收.细基江蓠繁枝变型NH4-N吸收的最适温度和盐度范围分别为15～25℃,10～25.生长率及NH4-N吸收速率与温度和盐度之间分别存在以下关系:SGRG.t.=0.873(S-5.487)(T-9.007)e(-0.0708S-0.0745T);SGRU.p.=0.222(S-2.665)e-0.047S(T-9.98)e-0.00057(T-9.98)2.7;SGRG.f.=2.6×10-4(S-10.856)(T-11.704)e0.156T-3.36×10-6STe0.219T;Vupt=11.812(S-4.081)(T-9.221)e-0.1S-0.148T. 相似文献
6.
本文选取抑食金球藻(Aureococcus anophagefferens)、中肋骨条藻(Skeletonema costatum)和海洋卡盾藻(Chattonella marina)三种藻在20℃和25℃下进行单种、两种或三种藻间的培养实验, 探究在不同温度下藻种间的相互作用和竞争优势。单种培养结果显示抑食金球藻和中肋骨条藻对温度25℃敏感, 其环境容量(K)被显著降低; 而海洋卡盾藻的內禀增长率(r)在25℃下显著升高, 但K保持不变。在共培养中, 海洋卡盾藻在20℃下因抑食金球藻添加致死, 但在25℃处理下其K值上升120%。虽然中肋骨条藻的r在两个温度下均受海洋卡盾藻添加的促进, 但其K值从20℃下的上升43%转变为25℃下的降低48%。温度变化对于抑食金球藻和中肋骨条藻共培养的结果无明显影响, 中肋骨条藻的K均上升40%, 而抑食金球藻的K值均下降60%~70%。结果说明, 种间竞争除了共培养藻固有的相互作用关系因素外, 也受到微藻间温度适应性差异的影响。在20℃条件下三种藻混合, 抑食金球藻K的抑制率达到最高为79%, 而中肋骨条藻K的促进率达到最高为108%, 这可能表明三者之间的相互作用存在协同效应。 相似文献
7.
8.
三疣梭子蟹(Portunus trituberculatus)幼体不同干露温度下死亡率的研究 总被引：1，自引：0，他引：1
通过设置15℃、20℃、25℃、30℃4个干露温度梯度,检测不同发育阶段三疣梭子蟹幼体的露空时间、死亡率、含水量、失水率及体重消耗率等指标,分析干露温度、发育阶段与幼体死亡率的关系。结果表明,各发育阶段的幼体死亡率均随干露时间的增加而升高(P<0.05);不同温度条件下,Ⅰ期幼蟹(CⅠ)的含水量、失水率和体重消耗率均高于Ⅱ期幼蟹(CⅡ)(P<0.05);CⅡ20℃时的露空时间最长,为11h,半致死时间为7—8h;30℃时最短,为2h;CⅠ15℃时的露空时间最短,为0.5h;20℃时最长,为4h。相同温度下,幼体各发育阶段的耐干露能力为CⅡ>CⅠ>ZⅣ>ZⅢ=M。结果说明,温度≤15℃不利于幼体的存活,温度≥25℃干露耐受性降低。因此,20℃更有利于幼体获得长存活时间。 相似文献
9.
温度对凡纳滨对虾幼体生长、变态和存活率的影响 总被引：1，自引：0，他引：1
通过不同水温的比较实验,研究了凡纳滨对虾人工育苗的适宜水温,旨在了解33℃及其以上水温对凡纳滨对虾幼体生长、变态和存活率可能造成的不良影响.实验结果表明,在29、31、33、35℃这4种温度实验组中,33℃组幼体的生长最快.Z1—P15期幼体的存活率以31℃组的最高（为29.8%）,其次是33℃组（为20.9%）,35℃组的最低（为4.7%）.实验过程中31℃组幼体的活力状态最佳、最稳定.因此,31℃左右是凡纳滨对虾幼体生长、发育的适宜水温.考虑到33℃组幼体的总存活率虽然低于31℃组,但其具有生长较快的优势,因此可认为目前凡纳滨对虾人工育苗普遍采用的31～32℃水温是合适的. 相似文献
10.
Larvae of the decapod Crangon uritai were reared in the laboratory in a factorial experiment employing three temperatures (9, 12 and 15 °C) and three salinities (29‰, 32‰ and 35‰) from hatching to the post‐larval stage. The effects of temperature and salinity on survival, intermolt period (IP) and molt increment (MI) were investigated. Larvae from one brood were subdivided into groups of 20 and reared in glass bowls containing filtered sea‐water at a number of temperature–salinity combinations. The reared larvae were transferred daily to the clean bowls prepared with newly hatched Artemianauplii, and number of molts and mortality within each bowl were recorded. The zoeal size (carapace length) was determined from exuvia and dead larvae, and the IP was also recorded. Larvae of C. uritai completed larval development only at 15 °C temperature. The first zoeal stage completed their development at all temperature–salinity combinations and exhibited the highest survival rate. IP at each stage increased with increasing size and greatly decreased with increasing temperature, and intermolt duration (range of days) increased with larval development especially at the lower temperature. Although the MI decreased with increasing size, it was little affected by temperature. This led to a better growth rate with increasing temperature. 相似文献
11.
S.G. Webster 《Estuarine, Coastal and Shelf Science》1982,15(1):85-94
A population of Palaemon elegans studied during 1978–1980 showed a characteristic moult cycle structure according to season, comprising a winter anecdysis, ‘epidemic’ spring moulting and synchrony of moult cycle development. The initiation of moulting in the spring was temperature-dependent, an estimated environmental temperature of 7–8 °C being necessary to allow moulting. Developmental synchrony during the moult cycle was observed following the initial spring moults, and it is thought that the degree and duration of moult synchrony is temperature-dependent. Synchrony is lost during the summer. Despite seasonal climatic differences between years, little difference in the time of appearance of berried females was seen. It is thought that oogenesis is controlled primarily by photoperiodic rather than temperature-dependent mechanisms. During egg development the moult cycle of ovigerous females was prolonged during intermoult stages and, during late vitellogenesis, premoult stages were prolonged. 相似文献
12.
13.
温度对半滑舌鳎的生长、生化组成和能量收支的影响 总被引：1，自引：0，他引：1
研究了不同温度(16,19,22,25,28和31 ℃)对半滑舌鳎(Cynoglossus semilaevis Günther)幼鱼的生长、体成分组成和能量收支的影响.结果表明,随温度的升高,半滑舌鳎幼鱼生长率总体呈现先升高后降低的趋势.其中,在19～25 ℃温度范围内,半滑舌鳎幼鱼的特定生长率相对较高,在16和28 ℃下则有所降低,而在31 ℃下,半滑舌鳎幼鱼特定生长率则显著降低.本研究表明半滑舌鳎幼鱼特定生长率与温度符合二次曲线模型.半滑舌鳎摄食量随温度升高而逐渐增大,但在31 ℃时显著减小,饵料转化率则随温度的升高而降低.鱼体脂肪与能值均随温度升高而降低,蛋白质含量受温度影响不显著.温度对半滑舌鳎的能量收支影响显著,其中,生长能和代谢能主导半滑舌鳎的能量分配,生长能占摄食能比例则随温度的升高而降低,呼吸能占摄食能比例则随温度的升高而升高.本研究表明,半滑舌鳎幼鱼(13～37 g)适宜生长温度范围为18～25 ℃,而不同温度导致的半滑舌鳎摄食量和能量收支的差异可能是温度影响其生长的主要生理生态学机制. 相似文献
14.
在不同温度和水流条件下,作者分别对八斑唇腕水母(Rathkea octopunctata)伞径、伞高、出芽率和存活时间等生长发育情况展开研究,以期为其人工饲养和科普展示奠定基础。近海9.5℃~14℃采集的八斑唇腕水母暂养1 d后,置于不同水流(静止的1 L烧杯和气泡带动水流的13 L水浴缸)和不同温度(10℃、15℃、20℃和22℃)交叉条件下人工饲养。结果显示,77 cm/s的水流条件下,10℃组水母存活时间最长。伞径、伞高与饲养时间呈负相关。温度越高,水母存活时间越短。温度能促进生殖腺快速成熟,但是10℃水母能持续性出芽。水流能保持水母活力,延长存活时间。研究表明,八斑唇腕水母可以通过水螅体横裂生殖和性腺出芽生殖两种方式繁育水母体。因为其个体较小,科技馆可采用低温水浴缸进行培养和长期展示,并对其特殊的出芽生殖方式进行科普讲解。 相似文献
15.
Using the 28°C isotherm to define the Western Pacific Warm Pool(WPWP), this study analyzes the seasonal variability of the WPWP thermohaline structure on the basis of the monthly-averaged sea temperature and salinity data from 1950 to 2011, and the dynamic and thermodynamic mechanisms based on the monthly-averaged wind,precipitation, net heat fluxes and current velocity data. A DT=–0.4°C is more suitable than other temperature criterion for determining the mixed layer(ML) and barrier layer(BL) over the WPWP using monthly-averaged temperature and salinity data. The WPWP has a particular thermohaline structure and can be vertically divided into three layers, i.e., the ML, BL, and deep layer(DL). The BL thickness(BLT) is the thickest, while the ML thickness(MLT) is the thinnest. The MLT has a similar seasonal variation to the DL thickness(DLT) and BLT.They are all thicker in spring and fall but thinner in summer. The temperatures of the ML and BL are both higher in spring and autumn but lower in winter and summer with an annual amplitude of 0.15°C, while the temperature of the DL is higher in May and lower in August. The averaged salinities at these three layers are all higher in March but lower in September, with annual ranges of 0.41–0.45. Zonal currents, i.e., the South Equatorial Current(SEC)and North Equatorial Counter Current(NECC), and winds may be the main dynamic factors driving the seasonal variability in the WPWP thermohaline structure, while precipitation and net heat fluxes are both important thermodynamic factors. Higher(lower) winds cause both the MLT and BLT to thicken(thin), a stronger(weaker)NECC induces MLT, BLT, and DLT to thin(thicken), and a stronger(weaker) SEC causes both the MLT and BLT to thicken(thin) and the DLT to thin(thicken). An increase(decrease) in the net heat fluxes causes the MLT and BLT to thicken(thin) but the DLT to thin(thicken), while a stronger(weaker) precipitation favors thinner(thicker)MLT but thicker(thinner) BLT and DLT. In addition, a stronger(weaker) NECC and SEC cause the temperature of the three layers to decrease(increase), while the seasonal variability in salinity at the ML, BL, and DL might be controlled by the subtropical cell(STC). 相似文献
16.
中国对虾(Penaeus chinensis)氮收支的初步研究 总被引：5，自引：2，他引：3
研究在20、25和30℃的正常海水(盐度为31)和5个盐度、水温为25℃条件下,分别测定了3个规格中国对虾摄食沙蚕和配合饲料的氮收支。研究结果表明,中国对虾的氮摄食率随温度的升高而增大,随体重的增加而减小;盐度为5时氮摄食率最小为11.78mg·g-1d-1,盐度为13时最大为13.88mg·g-1d-1.生长氮的比例随温度的升高显着减小;盐度为20的生长氮比例最大为26.52%,此时的特定生长率也最大为7.8%,盐度为5时的最小。中国对虾摄食沙蚕和配合饲料的平均氮收支模式分别为100I=27.63G+3.58E+1.66F+67.13U;100I=18.34G+4.10E+6.07F+71.49U. 相似文献
17.
温度突变对大海马(Hippocampus kuda)幼体生长、组分及酶活力的影响 总被引：1，自引：0，他引：1
以大海马幼体为实验材料,通过设置不同的温度突变组(温度从23℃突变至15℃、28℃和33℃)的方法,对其生长、生化组分以及酶活力的影响进行了研究。结果表明,实验结束后,28℃温度组的大海马幼体生长指标、蛋白含量、能值显著高于23℃对照组(P<0.05),而15℃、33℃温度组的各项指标则显著低于对照组(P<0.05);此外,温度突变组的大海马幼体的酶活力均有先升后降的趋势,在1d后出现峰值,4—6d各个温度组趋于稳定,到实验第15天时,28℃温度组的SOD、ACP活力和MDA的含量已处于23℃对照组水平(P>0.05),CAT、AKP活力显著高于23℃对照组(P<0.05)。而15℃、33℃温度组的SOD、CAT活力降至低于23℃对照组水平(P<0.05),15℃温度组的ACP、AKP活力则低于23℃对照组水平(P<0.05),MDA的含量在15℃、33℃温度组随时间延长而增加。 相似文献
18.
温度对条石鲷幼鱼代谢率、排泄率及窒息点的影响 总被引：2，自引：0，他引：2
采用静水密闭式呼吸仪,分别测定了13,18,23,28和33℃5个水温梯度下条石鲷Oplegnat-hus fasciatus幼鱼的代谢率、排泄率及窒息点。结果表明:(1)不同温度条件下,条石鲷幼鱼的代谢率和排泄率差异显著(p<0.05);当温度由13℃升高至28℃时,条石鲷幼鱼的代谢率和排泄率均随之升高;当水温为28℃时,其代谢率和排泄率达最大值,分别为(16.33±0.45)J/(g·h)和(1.03±0.04)J/(g·h),是13℃实验组的6.69倍和5.15倍;与28℃实验组相比,33℃实验组的代谢率和排泄率分别降低了19.04%和15.53%,33℃已超出了条石鲷幼鱼生长的最高适温。(2)实验温度下,条石鲷幼鱼的蛋白质供能比值为37.94%～72.24%,蛋白质是其主要能源物质。(3)条石鲷幼鱼的窒息点为(3.17～3.64)mg/L,并随水温升高而升高。(4)Q10值和蛋白质供能比值的变化特征表明,18～28℃是条石鲷幼鱼的适宜生长温度。 相似文献
19.
杂交鲷和黑鲷幼鱼的代谢率及排泄率比较 总被引：1，自引：0，他引：1
杂交鲷是以真鲷为母本,黑鲷为父本的杂交F1代品种,为了比较杂交鲷与黑鲷的代谢特征,采用静水密闭式呼吸仪测定了13、18、23、28、33℃（32℃）5个温度下杂交鲷和黑鲷幼鱼的代谢率及排泄率.结果表明：13~28℃温度下,杂交鲷和黑鲷幼鱼的代谢率、排泄率均随温度的升高而升高,28℃时杂交鲷和黑鲷幼鱼的代谢率、排泄率分别为14.22±0.95、0.39±0.02 J/（g.h）和17.47±0.14、0.43±0.02 J/（.gh）,分别是其13℃时的5.69、4.05倍和4.01、3.73倍;且各温度下黑鲷的代谢率始终高于杂交鲷,前者是后者的1.23~1.73倍;杂交鲷和黑鲷幼鱼分别在32℃和33℃时代谢率比28℃下跌了22.23%和3.83%,证明该温度已分别超出了这2种幼鱼的最高适温;杂交鲷和黑鲷幼鱼28℃时的窒息点溶解氧含量分别为1.94、1.40 mg/dm3,低于真鲷21℃时的窒息点溶解氧含量（2.30 mg/dm3）;O∶N原子比值结果显示,28℃时蛋白质供能比最低,生长积累速度最快,是2种幼鱼的最适温度.综合分析认为,杂交鲷幼鱼具有代谢率显著低于亲本的优点,也继承了父本耐低温的特点,但同时失去了亲本耐高温、耐低氧的特点,并出现了应激反应大等不良性状. 相似文献
20.
采用静水呼吸室法,研究了温度、盐度和两种麻醉剂(丁香油、MS-222)对体质量为(6.44±0.59)g的大泷六线鱼幼鱼耗氧率和排氨率的影响。实验分别设置了5个温度梯度(8℃、12℃、16℃、20℃、24℃),5个盐度梯度(15‰、20‰、25‰、30‰、35‰),6个丁香油浓度梯度(0、8、16、24、32、40 mg/L)和5个MS-222浓度梯度(0、10、20、30、40 mg/L)。结果显示,温度、盐度和两种麻醉剂均对耗氧率和排氨率有显著性影响。8℃时,耗氧率和排氨率最低,随温度升高先升高后降低,且均在20℃时达到峰值;盐度30‰时,耗氧率和排氨率最低,盐度升高或降低都会导致耗氧率和排氨率升高;丁香油和MS-222均能有效降低大泷六线鱼的耗氧率和排氨率,其中丁香油的降低效果更为明显;丁香油浓度为24 mg/L时或MS-222为20 mg/L时可使大泷六线鱼处于深度镇定期,结合耗氧率及排氨率变化,认为上述浓度是大泷六线鱼幼鱼保活运输的最佳浓度;本研究所有处理组的O∶N比值范围均在14.77~24.11之间,表明适宜温度和盐度条件下,大泷六线鱼幼鱼主要由蛋白质和脂肪提供能量。研究认为,适度降温、自然盐度和适宜浓度的麻醉剂处理均可显著降低大泷六线鱼幼鱼的呼吸代谢强度,其中丁香油相比MS-222作用效果更加明显。本研究结果为实现大泷六线鱼高质量运输提供了科学参考。 相似文献