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1.
南方鲇的鱼体能量密度及其预测模型   总被引:13,自引:0,他引:13  
于1992年和1993年2-4月由嘉陵江收集的野生南方鲇雌、雄成鱼各20尾;1996年1-4月取得了不同摄食水平处理的幼鱼19尾,饥饿处理的幼鱼18尾,测定了这4个样本的鱼体能量密度及化学组成。结果表明,各样本能量密度均分别与干物质和脂肪含量呈显著的直线相关关系;幼鱼2个样本的能量密度与蛋白质含量的正相关关系也达到显著性,而雌、雄成鱼样本的能量密度分别与干物质(DM:%B.W.)的直线回归方程的协方差分析,可将雌雄成鱼群体的两个回归方程合并为公共的成鱼能量密度(EA:kJ/g)方程:EA=1.67+0.302DM;将不同营养状况幼鱼的两个回归方程合并为公共的幼鱼能量密度(D1:kJ/g)方程:EJ=-2.26+0.329DM。  相似文献   

2.
Book review     
Geotechnical Aspects of Coastal and Offshore Structures. Edited by Yudhair and A. S. Balasubramaniam. Proceedings of the Symposium on Geotechnical Aspects of Coastal and Offshore Structures, Bangkok, December 14–18,1981. Rotterdam: A. A. Balkema, 1983. 280 pp. $40.00.

The Seaside Naturalist: A Guide to Nature Study at the Seashore. Written and illustrated by D. A. Coulombe. Englewood Cliffs, N.J.: Prentice‐Hall, Inc., 1984. 246 pp. $12.95.

Ichnology, Trace Fossils in Sedimentology and Stratigraphy. By A. A. Ekdale, R. G. Bromley, and S. G. Pemberton. Society of Economic Paleontologists and Mineralogists, Short Course No. 15. Tulsa, Okla.: S.E.P.M., 1984. 317 pp. S.E.P.M. members, $16.00; non‐members, $20.00.  相似文献   

3.
封闭循环养殖系统中驼背鲈和斜带石斑鱼生长的研究   总被引:1,自引:1,他引:1  
研究闭合循环水养殖条件下驼背鲈(Cromileptes altivelis)和斜带石斑鱼(Epinephelus coioides)的生长特性。经343d养殖,驼背鲈幼鱼平均体质量由24.16g增加到124.4g,平均日生长率为1.2%.体质量与养殖时间的关系式为M=32.674e^0.0048t,体质量与体长的关系式为M=0.0042L^3.6184;斜带石斑鱼幼鱼体质量由20.10g增加到490g,平均日生长率为6.8%,体质量与养殖时间的关系式为M=34.319e^0.0984t,体质量与体长的关系式为M=0.0656L^2.7102。  相似文献   

4.
采用AFLP技术和单因素方差分析方法,进行了青蛤主要生长性状相关分子标记筛选研究。结果表明,检测的18个与壳长相关的基因位点,其贡献率在6.46%—18.32%之间,其中E32M51-8、E33M51-38对壳长的贡献率较高,分别为18.32%和15.68%。检测的23个与壳宽相关的基因位点,其贡献率在6.75%—20.93%之间,其中E32M51-8、E33M48-19对壳宽的贡献率较高,分别为20.93%和17.34%。检测的22个与壳高相关的基因位点,其贡献率在6.54%—15.91%之间,其中E32M51-17对壳高的贡献率最高,为15.91%。检测的8个与活体重相关的基因位点,其贡献率在6.65%—17.83%之间,其中E33M48-10对活体重的贡献率最高,为17.83%。以上结果说明青蛤生长性状的遗传基础复杂,通过筛选与其相关显著的分子标记,在育种中开展分子标记选择是可行的。  相似文献   

5.
 Magnetic data over the eastern continental margin of India and adjacent Bengal fan demarcate two major lineaments. A high amplitude N–S-trending lineation of the Cauvery offshore Basin corresponds to the offshore fragment of the 80°E lineament recorded onland. A N–S lineation of very high amplitude anomaly off Chilka lake considered as the possible northward extension of the 85°E ridge delineated, hitherto in Bengal Fan. A subdued magnetic anomaly zone is demarcated seaward of the continent–ocean boundary (COB) in the Bengal Fan. Over the northern Bengal Fan this zone is delineated east of 85°E lineation. This quiet zone might have evolved during the Early Cretaceous period of normal magnetic polarity between M0 and 34 (120–84 Ma) anomalies. Received: 6 April 1995 / Revision received: 3 September 1996  相似文献   

6.
Estrogens appear to have a modulating effect on the expression of cytochrome P4501A (CYP1A) in fish. A number of in vivo studies have demonstrated that hepatic CYP1A expression in females decrease during sexual maturation when plasma levels of 17 beta-estradiol (E2) increase, or in cases when the fish in injected with E2. Since a number of environmental contaminants have weak estrogen-like activities, the question arises if these compounds are able to modulate CYP1A expression as well. In the present study, we used in vitro monolayer cultures of rainbow trout, Oncorhynchus mykiss, liver cells to compare concentration-dependent (10(-9) to 10(-5) M) effects of the natural steroid E2 and the non-steroidal xenoestrogen 4-tert-octylphenol (OP) on CYP1A-catalyzed 7-ethoxyresorufin-O-deethylase (EROD) activity. The concentration dependency of the estrogenic activity of the two test compounds was assessed by determination of hepatocellular vitellogenin (Vg) release into the culture medium. Exposure of hepatocytes to E2 concentrations of 10(-8) M and higher led to a significant inhibition of basal cellular EROD activity. On the contrary, exposure to OP did not result in an inhibition of EROD activity, even at OP concentrations (10(-6) M, 10(-5) M) which were associated with a significant induction of Vg synthesis.  相似文献   

7.
Referees     
The Editors are pleased to take this opportunity to record theirgratitude to the following referees (reviewers) for their prompt,thoughtful, and constructive reports.
Abella, A.
Afonso, J. M.
Agnalt, A-L.
Agnew, D.
Agostini,V.
Aguzzi, J.
Ahsan, N.
Aksland, M.
Allcock, A. L.
Andersen,K. H.
Anderson, C. I. H.
Anderson, J. T.
Anderson, K.
Andrade, J. P.
Andrews, A.
Apostolaki, P.
Appleyard,S. A.
Aprahamian, M. W.
Arkhipkin, A. I.
Armstrong, M.J.
Arneri, E.
Arnott, S.
Aro, E.
Åström,M.
Auster, P. J.
Bailey, N.
Balguerías, E.
Balke,H.
Bannister, R. C. A.
Barange, M.
Bathman, U.
Beal,B.
Bégout,  相似文献   

8.
Book review     
Marion and Prince Edward Islands. Report on the South African Biological and Geological Expedition 1965–1966. Edited by E. M. van Zinderen Bakker, J. M. Winterbottom and R. A. Dyer. Balkema, Cape Town. $25.33.  相似文献   

9.
The esterification of two model vertebrate steroid hormones – estradiol (E2) and dehidroepiandrosterone (DHEA) – was studied in the oyster Crassostrea virginica. The activity of acyl-CoA:steroid acyltransferase was characterized in microsomal fractions isolated from oyster digestive glands. The apparent Km and Vmax values changed with the fatty acid acyl-CoA used (C20:4, C18:2, C18:1, C16:1, C18:0 or C16:0), and were in the range of 9–17 μM, and 35–74 pmol/min/mg protein for E2, and in the range of 45–120 μM, and 30–182 pmol/min/mg protein for DHEA. Kinetic parameters were also assessed in gonadal tissue. The enzyme saturated at similar concentrations, although conjugation rates were lower than in digestive gland. Preliminary data shows that tributyltin (TBT) in the low μM range (1–50) strongly inhibits E2 and DHEA esterification, the esterification of E2 being more sensitive to inhibition than that of DHEA. Overall, results indicate that apolar conjugation occurs in oysters, in both digestive gland and gonads, at a very similar rate to mammals, suggesting that this is a well conserved conjugation pathway during evolution. Esterification, together with other mechanisms, can modulate endogenous steroid levels in C. virginica, and might be a target for endocrine disrupters, such as TBT.  相似文献   

10.
Re: Kirby, D. S.; Abraham, E. R.; Uddstrom, M. J.; Dean, H. 2003: Tuna schools/aggregations in surface longline data 1993–98. New Zealand Journal of Marine and Freshwater Research 37: 633–644.  相似文献   

11.
Book review     
Jane's Ocean Technology 1974–75 by Robert L. Trillo (Editor). Jane's Yearbooks, London, England (in North America, Franklin Watts, Inc., New York), 1974. 344 pp. £12.50 ($55.00).

The Ocean Basins and Margins—Volume 2: The North Atlantic by A. E. M. Nairn and F. G. Stehli (Editors). Plenum Publishing, New York, 1974. 598 pp. $38.00.  相似文献   

12.
研究了海洋链霉菌分离株M095的基因转移系统。利用属间接合转移将具有oriT的大肠杆菌-链霉菌穿梭质粒pIJ8600转入EscherichiacoliET12567(pUZ8002)中,获得供体菌。将供体菌与预萌发的菌株M095的孢子进行接合转移,将质粒pIJ8600转入菌株M095中,其转化率为1.99×10-4个接合转化子/受体。Southern杂交证明质粒pIJ8600已经整合到菌株M095的染色体上。同时,将来自Spirulinamaxima(Cyanophyta)的别藻蓝蛋白基因(apc)克隆在质粒pIJ8600的XbaI和BglII位点,产生质粒pAPIJ。用接合转移法将质粒pAPIJ转入菌株M095。通过SDS-PAGE分析,得到2个大小为22ku和17ku的蛋白,分别相对应于别藻蓝蛋白的α和β亚基。这些结果进一步证明菌株M095的遗传转化体系已经成功建立起来,这将为其他海洋放线菌遗传转化工作的研究奠定基础。  相似文献   

13.
In this paper we present a methodology to estimate the probability of future coastal flooding given uncertainty over possible sea level rise. We take as an example the range of sea level rise magnitudes for 2100 contained in the IPCC Third Assessment Report [Church, J.A., Gregory, J.M., Huybrechts, P., Kuhn, M., Lambeck, K., Nhuan, M.T., Qin, D., Woodworth, P.L., Anisimov, O.A., Bryan, F.O., Cazenave, A., Dixon, K.W., Fitzharris, B.B., Flato, G.M., Ganopolski, A., Gornitz, V., Lowe, J.A., Noda, A., Oberhuber, J.M., O'Farrell, S.P., Ohmura, A., Oppenheimer, M., Peltier, W.R., Raper, S.C.B., Ritz, C., Russell, G.L., Schlosser, E., Shum, C.K., Stocker, T.F., Stouffer, R.J., van de Wal, R.S.W., Voss, R., Wiebe, E.C., Wild, M., Wingham, D.J. and Zwally, H.J., 2001. Changes in sea level. In Houghton, J.T. et al. (eds), Climate Change 2001: The Scientific Basis. Contribution of Working Group I to the Third Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, United Kingdom, 881pp.] and infer a plausible probability distribution for this range. We then use a Monte Carlo procedure to sample from this distribution and use the resulting values as an additional boundary forcing for a two-dimensional model of coastal inundation used to simulate a 1 in 200 year extreme water level event. This yields an ensemble of simulations for an event of this magnitude occurring in 2100, where each member represents a different possible scenario of sea level rise by this time. We then develop a methodology to approximate the probability of flooding in each model grid cell over the ensemble and by combining these hazards maps with maps of land use values (consequence) we are able to estimate spatial contributions to flood risk that can aid planning and investment decisions. The method is then applied to a 32 km section of the UK coast in Somerset, South-West England and used to estimate the monetary losses and risk due a 1 in 200 year recurrence interval event under: (a) current conditions; (b) with the IPCC's most plausible value for sea level rise by 2100 (0.48 m) and (c) using the above methodology to fully account for uncertainty over possible sea level rise. The analysis shows that undertaking a risk assessment using the most plausible sea level rise value may significantly underestimate monetary losses as it fails to account for the impact of low probability, high consequence events. The developed method provides an objective basis for decisions regarding future defence spending and can be easily extended to consider other sources of uncertainty such as changing event frequency–magnitude distribution, changing storm surge conditions or model structural uncertainty, either singly or in combination as joint probabilities.  相似文献   

14.
Estimating the age of particles in marine environment constitutes an invaluable tool to understand the interactions between complex flows and sediment dynamics, particularly in highly energetic coastal areas such as the Belgian Coastal Zone (Southern Bight in the North Sea). To this end, the Constituent Age and Residence time Theory – CART – introduced by Delhez, E.J.M., Campin, J.-M., Hirst, A.C., Deleersnijder, E. [1999a. Toward a general theory of the age in ocean modelling. Ocean Modelling 1, 17–27] for passive water constituents is extended to describe the sediment dynamics. It is then used in combination with a three-dimensional coupled hydrodynamic-sediment transport model to investigate sediment processes in the Belgian Coastal Zone focusing on two complementary aspects of the sediment dynamics: the internal sediment motion and redistribution within the Belgian coast; and the horizontal transport.  相似文献   

15.
The vertical distributions of cobalt, iron, and manganese in the water column were studied during the E-Flux Program (E-Flux II and III), which focused on the biogeochemistry of cold-core cyclonic eddies that form in the lee of the Hawaiian Islands. During E-Flux II (January 2005) and E-Flux III (March 2005), 17 stations were sampled for cobalt (n=147), all of which demonstrated nutrient-like depletion in surface waters. During E-Flux III, two depth profiles collected from within a mesoscale cold-core eddy, Cyclone Opal, revealed small distinct maxima in cobalt at 100 m depth and a larger inventory of cobalt within the eddy. We hypothesize that this was due to a cobalt concentrating effect within the eddy, where upwelled cobalt was subsequently associated with sinking particulate organic carbon (POC) via biological activity and was released at a depth coincident with nearly complete POC remineralization [Benitez-Nelson, C., Bidigare, R.R., Dickey, T.D., Landry, M.R., Leonard, C.L., Brown, S.L., Nencioli, F., Rii, Y.M., Maiti, K., Becker, J.W., Bibby, T.S., Black, W., Cai, W.J., Carlson, C.A., Chen, F., Kuwahara, V.S., Mahaffey, C., McAndrew, P.M., Quay, P.D., Rappe, M.S., Selph, K.E., Simmons, M.P., Yang, E.J., 2007. Mesoscale eddies drive increased silica export in the subtropical Pacific Ocean. Science 316, 1017–1020]. There is also evidence for the formation of a correlation between cobalt and soluble reactive phosphorus during E-Flux III relative to the E-Flux II cruise that we suggest is due to increased productivity, implying a minimum threshold of primary production below which cobalt–phosphate coupling does not occur. Dissolved iron was measured in E-Flux II and found in somewhat elevated concentrations (0.5 nM) in surface waters relative to the iron depleted waters of the surrounding Pacific [Fitzwater, S.E., Coale, K.H., Gordon, M.R., Johnson, K.S., Ondrusek, M.E., 1996. Iron deficiency and phytoplankton growth in the equatorial Pacific. Deep-Sea Research II 43 (4–6), 995–1015], possibly due to island effects associated with the iron-rich volcanic soil from the Hawaiian Islands and/or anthropogenic inputs. Distinct depth maxima in total dissolved cobalt were observed at 400–600 m depth, suggestive of the release of metals from the shelf area of comparable depth that surrounds these islands.  相似文献   

16.
接种生物胺降解菌对鱼露生物胺含量及品质的影响   总被引:1,自引:0,他引:1  
将两株生物胺降解菌Millerozyma farinose A3和Enterococcus faecium R7(简称降胺菌)接种到发酵鱼露中,探究接种M.farinose A3、E.faecium R7及两者复合菌对发酵鱼露生物胺含量及品质的影响。研究表明:接种降胺菌组鱼露生物胺含量显著低于对照组,且接种复合降胺菌鱼露生物胺含量最低(P<0.05)。与对照组相比,接种降胺菌能降低发酵过程中鱼露的pH,促进乳酸菌的生长同时抑制肠杆菌的生长(P<0.05);抑制挥发性盐基氮的生成,抑制呈鱼腥味的三甲胺和庚醛的生成;促进乙酸乙酯等令人愉悦的风味物质的生成,促进游离氨基酸特别是必需氨基酸的生成。本研究中M.farinose A3和E.faecium R7能降低鱼露生物胺含量,提高食用安全性,同时还能提升鱼露的风味和营养,其有望成为鱼露的新型发酵剂。  相似文献   

17.
Mytilus galloprovincialis digestive gland microsomes were prepared from (i) indigenous populations sampled from a clean reference (Lido) and an urban-contaminated site (Salute) and (ii) mussels transplanted for up to 3 weeks from Lido to an industrial-contaminated site (CVE) in Venice Lagoon, Italy. Western blot analysis was performed using antibodies to five mammalian or fish CYP forms (1A, 2B, 2E, 3A, 4A). Simultaneously run M. edulis digestive gland partially purified CYP aided identification of immunopositive bands. Levels of CYP1A, CYP2E, and CYP4A-immunopositive proteins were 50 to 300% higher in indigenous M. galloprovincialis from Salute compared to Lido (p < 0.05). Three weeks after transplantation to CVE, levels of only the CYP1A-immunopositive protein were determined to be higher (63%) than levels for Lido (p < 0.05), indicating that anti-CYP1A shows greater specificity for a contaminant-inducible CYP form than the other antibodies.  相似文献   

18.
Natural mortality rate(M) is one of the essential parameters in fishery stock assessment, however, the estimation of M is commonly rough and the changes of M due to natural and anthropogenic impacts have long been ignored.The simplification of M estimation and the influence of M variations on the assessment and management of fisheries stocks have been less well understood. This study evaluated the impacts of the changes in natural mortality of Spanish mackerel(Scomberomorus niphonius) on their management strategies with data-limited methods. We tested the performances of a variety of management procedures(MPs) with the variations of M in mackerel stock using diverse estimation methods. The results of management strategies evaluation showed that four management procedures DCAC, SPMSY, cur E75 and minlen Lopt1 were more robust to the changes of M than others; however, their performance were substantially influenced by the significant decrease of M from the 1970s to 2017. Relative population biomass(measure as the probability of B0.5 BMSY) increased significantly with the decrease of M, whereas the possibility of overfishing showed remarkable variations across MPs. The decrease of M had minor effects on the long-term yield of cur E75 and minlen Lopt1, and reduced the fluctuation of yield(measure as the probability of AAVY15%) for DCAC, SPMSY. In general, the different methods for M estimation showed minor effects on the performance of MPs, whereas the temporal changes of M showed substantial influences. Considering the fishery status of Spanish mackerel in China, we recommended that cur E75 has the best trade-off between fishery resources exploitation and conservation, and we also proposed the potentials and issues in their implementations.  相似文献   

19.
采用捕食者.猎物间捕食效应研究方法,研究了日本鳗鲡对3种体长规格日本沼虾的捕食效应.结果表明:(1)日本鳗鲡与日本沼虾的主要活动时段均为17:00至翌日5:00,期间日本沼虾的活动量随其体长规格的增大而减少,日本鳗鲡的主要捕食时段为0:00-5:00,其对体长2.4cm左右的日本沼虾有较强的追捕行为;(2)日本鳗鲡对日...  相似文献   

20.
Oceanography, Units 1–16 edited by J. Stewart (Open University Press, 1977), 755 pp.

The Thermohaline Fine Structure of the Ocean by K. N. Fedorov (New York: Pergamon Press, Pergamon Marine Series. Volume 2, 1978). Translated from Russian by D. A. Brown, Technical Editor: J. S. Turner, 170 pp., no price listed.

The Ocean Basins and Margins edited by Alan E. M. Nairn and Francis G. Stehli, with William H. Kanes (New York: Plenum Press, Vol. 1–4A, 4B, 1973, 1979, 1975, 1977, and 1978) approx. 3,000 pp.

Recent Crustal Movements, 1977 edited by C.A. Whitten, R. Green, and B.K. Meade (New York: Elsevier Scientific Publishing Co., 1979), 663 pp., hardcover, $78.00.

The Alaskan Shelf‐Hydrographic, Sedimentary, and Geotechnical Environment by Ghanshyam Datt Sharma (New York: Springer Verlag, 1979), 498 pp., hardcover, $29.80.  相似文献   

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