Should total landings be used to correct estimated catch in numbers or mean weight-at-age?     

Lewy  Peter; Lassen  Hans 《ICES Journal of Marine Science》1997,54(3):462-470

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Spatio-temporal variability of small copepods (especially Oithona plumifera) in shallow nearshore waters off the south coast of South Africa   总被引：1，自引：0，他引：1  

Francesca Porri  Christopher D. McQuaid  William P. Froneman 《Estuarine, Coastal and Shelf Science》2007,72(4):711-720

Although small copepods are one of the main dietary sources for many commercially important fish, their role in the pelagic trophic dynamics has traditionally been underestimated due to the methodology commonly used in plankton sampling. Temporal variation in abundance of adults and nauplii of small copepods (particularly Oithona plumifera) in nearshore waters on the south coast of South Africa was investigated fortnightly over 14 months at site (km) and location (100 m) scales. Sampling was within <500 m of the shore, where depth was ca. 10 m, using vertical hauls of an 80-μm mesh plankton net from 1 m above the seabed to the surface. Twenty-seven adult copepod taxa were recorded, but Oithona spp. was consistently the most abundant. Taxon richness was 7–19 on each sampling occasion. There was strong temporal variation (Oithona varied between 0 and 2300 m⁻³), but much of this was short-term variability (e.g. between consecutive sampling sessions), with no seasonality or other long-term discernable patterns. There were periods of consistently low numbers, but very high numbers often followed samples with low abundances. Nor was there spatial structure at the location scale, though numbers differed between sites. Despite considerable variability at the location scale within sites, Kenton consistently showed higher densities than High Rocks. Separate analyses, with Bonferroni adjustment, showed that this difference was significant on eight out of 21 occasions for Oithona, six for other pelagic copepods and three for nauplii. This suggests that hydrodynamics favour aggregation of plankton at Kenton. A high degree of short-term variability, with a tendency for aggregation of small zooplankton at certain sites has implications for both pelagic processes and food-web links between the benthic and pelagic environments.  相似文献   

裙带菜配子体基因工程选择标记的研究          下载免费PDF全文

张亦陈  高江涛  张喆  姜鹏  秦松 《海洋科学》2007,31(12):64-68

研究了裙带菜(Undaria pinnatifida)配子体对除草剂草丁膦的敏感性以及温度对草丁膦处理效果的影响。结果表明,裙带菜配子体对草丁膦敏感;统计学分析得出了草丁膦在不同温度条件下处理裙带菜配子体的半致死浓度(LD50)及95%可信限;温差达到10℃时,相同处理时间各组内不同处理温度样品的LD50之间呈现显著差异,第6天的LD50由10℃组的15.78 mg/L降为20℃组的11.56 mg/L和25℃组的10.33 mg/L。研究发现可以尝试采用草丁膦作为裙带菜配子体遗传转化的选择试剂。  相似文献   

欧式鳕鱼排的研制   总被引：2，自引：0，他引：2  

桑卫国  吴汉民  韩素珍 《海洋学研究》2002,20(1):55-59

以鳕鱼为原料 ,经过鱼糜制作、调味、速冻、切片、浸液、沾粉、二次速冻等工艺研制开发了欧式鳕鱼排。探讨了原、辅料和漂洗条件对产品质量的影响 ,测定了评价产品质量的感官、理化和微生物指标。  相似文献   

RTK GPS在无验潮水深测量中的应用   总被引：3，自引：0，他引：3  

栗志刚  孙仁权 《海洋测绘》2005,25(5):46-48

介绍了应用全球定位系统实时动态测量（RTK GPS）技术进行无验潮水深测量的基本方法，并在实际工作中进行了验证。  相似文献   

中华鲟随机扩增多态性DNA及遗传多样性研究   总被引：43，自引：5，他引：43  

张四明  邓怀  晏勇  汪登强  吴清江 《海洋与湖沼》2000,31(1):1-7

采用随机扩增多态性ＤＮＡ（ＲＡＰＤ）技术进行了连续３年（１９９５－１９９７）共７０尾来源于长江水系中华鲟样本遗传分析,共用了４０个１０ｂｐ长的随机引物,在２６种可供分析的引物中,只有ＯＰＫ０１、ＯＰＫ０２、ＯＰＫ０３、ＯＰＫ０９、ＯＰＫ１４和ＯＰＱ０８ＲＡＰＤ－ＰＣＲ产物有多态现象,多态引物占２３％。２６个引物中共扩增出１０８条稳定的ＤＮＡ带。其中１２条带为多态带,多态座位比例为１１．１％。个体间  相似文献   

Consequences of growth variation in northern Baltic herring for assessment and management     

Rahikainen  Mika; Stephenson  Robert L. 《ICES Journal of Marine Science》2004,61(3):338-350

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海浪日最大波高序列的一种标度性质   总被引：1，自引：0，他引：1  

尉华  沈正 《海洋湖沼通报》1994,(4):1-8

应用重标度分析方法研究小麦岛海洋观测站１９６１－１９８０年二十年海浪日最大波高序列时发现，该序列并不是相互独立的，而是具有记忆性和持久性，详细的论证表明分式布朗运动模型是描述海浪日最大波高序列的一个较好的模型，同时，应用分式布朗运动模型我们找到了存在于海浪日最大波高序列中的一种标度性质－累积离差（ｔ）的统计自仿射性。  相似文献   

黄海多毛类异毛虫科初步研究     

赵晶  吴宝铃 《海洋科学进展》1991,(2)

本文对1987～1988年在山东省部分海岛底栖生物调查时发现的异毛虫科5个种进行了详细的描述并配有插图,其中一种为新亚种,另有3个种在我国为首次记录。  相似文献   

裙带菜褐藻糖胶的分离及部分理化性质研究   总被引：1，自引：0，他引：1  

赖晓芳  沈善瑞  徐士军 《海洋技术学报》2006,25(4):58-60

以裙带菜为原材料,采用水提法从裙带菜中分离褐藻糖胶,Sevag法去蛋白,乙醇分步沉淀法进行初步纯化。结果表明裙带菜褐藻糖胶的最适提取温度为80℃,时间为8 h,加水量为1∶30,在最适条件下的提取率为1.72%,蛋白质含量为5.44%。同时本研究对部分理化性质进行了研究。结果是特性粘度为5 m pa.s,pH为8.50,含有硫酸基。  相似文献