982 resultados para Figures
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The attractiveness of the trophic concept is that it was the first attempt at a holistic perspective on an ecosystem which met with any degree of success. Just as temperature, pressure, and volume allow one to characterize the incomprehensible multitude of particulate motions in a simple gas, the hope is that a small set of figures, such as trophic storages or trophic efficiencies, permit one to compare two ecosystems with overwhelmingly disparate complexities. Thus, if it were possible to demonstrate that an arbitrary network of ecosystem flows could be reduced to a trophic configuration, the aggregation process thus defined would become a key component of the evolving discipline of "macroscopic ecology" (see also Odum 1977 and Ulanowicz 1979).
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Fish were collected weekly in Biscayne Bay using a monofilament gill net set from a small skiff during 20-30 minute intervals. Although weekly sampling took place for 2.5 years, only the data from samples collected from June 1976 to June 1977 were used in this document. Abnormal external conditions of fins and body were observed on each fish and recorded. Fish were returned immediately to their habitats. Fish collected in the time period for this study numbered 3,765 and included 32 species. Of these, 16 species, totaling 3,556 fish, were caught in sufficient numbers (20 or more) to warrant data analysis. Only 3 of the 16 species could be considered relatively unafflicted: Aetobatus narinari (spotted eagle ray), Diodon hystrix (porcupinefish), and Selene vomer (lookdown). More than 80% of the examined specimens of these three species were unaffected. Less than 20% of the specimens of Diapterus plumieri (striped mojarra), Micropogonias undulatus (Atlantic croaker), and Pogonias cromis (black drum) displayed normal conditions. The three most afflicted species were Diapterus plumieri, striped mojarra; Micropogonias undulatus, Atlantic croaker; and Pogonias cromis, black drum. Only 7, 3, and 7% respectively showed no external evidence of disease. Data described in this document were originally tabulated in the mid-1970s, remained unpublished, and are no longer available. This document was based on archived unpublished text, a data summary table, and figures. Most of the text and cited references were the ones used in the original manuscript and no attempt was made to update them. (PDF contains 44 pages)
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The commercially important species of penaeoid shrimps comprise 4 families, 12 genera, and 37 species in the Americas, This key is supported by 49 figures including lateral views of whole shrimps in 10 of the 12 genera and detailed figures of male (petasma) and female (thelycum) genital structures of the species. A glossary of terms used in shrimp taxonomy plus a bibliography of references useful in identifying shrimps are included. (PDF file contains 38 pages.)
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Expendable bathythermograph data collected by the Ships of Opportunity (SOOP) - Ocean Monitoring Program are analyzed for seasonal and inter-annual variations of the cold pool. Two major SOOP transects within the Middle Atlantic Bight (Southern New England and New York) have been analyzed for the years common to both (1977-81). During the years 1977-81, over 200 transects were occupied, and almost 3,000 XBT's were dropped. Results show that the cold pool is formed with the onset of spring warming and persists until fall overturn, is consistent year to year in both area and weighted average annual temperature, and advects water from the northeast to the southwest. Results also show a 100-d lag in minimum temperature between the Southern New England and New York transects. DitTerences in bathymetry between the two transects and their influence on the cold pool are also discussed. Plots of average (1977-81) bottom temperature for both transects are discussed and show consistent annual weighted mean temperature and areas. Bottom temperature plots for individual years, as well as maximum and minimum bottom temperature plots, are presented as Appendix figures. (PDF file contains 28 pages.)
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The goal of this work is to present a collection of drawings and figures depicting the species present in our country. To achieve this, our main sources of information have been the works of Ringuelet et al. (1967), Reis et al. (2003), and López et al. (2003; 2006), as well as the online databases of W. N. Eschmeyer and Fish Base. Each species has an individual factsheet with selected images, including some from anatomical research works. All the works referenced are mentioned in each factsheet. This is an open-ended publication. As such, it will require permanent updating, which will depend on the good will and collaboration of the ichthyological community. As compilers, we understand that this contribution not only provides valuable information, but also highlights the work of men and women who are part of the rich history of our national and regional ichthyology.
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The pressure of users other than shipping and fishery on the national EEZs for territorial claims has increased in recent years. So it becomes necessary to carry out a spatial planning for which all users have to indicate their recent and planned future activities. For the German waters in the North Sea a first attempt was made to calculate the mean international landings for the commercially important fish and crustacean species on the spatial scale of ICES-rectangles. The relationships between the German and international landings per species are listed in a table and the distribution of the landings for each species within the area are shown in 13 figures.
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Comunicación presentada en el II Congresso Peninsular de Historia Antigua (Coimbra, 1990)
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[ES] El programa de cooperación transnacional del Suroeste Europeo aporta la oportunidad de contrastar la situación que atraviesan los espacios periurbanos de cuatro áreas metropolitanas y plantear toda una serie de recomendaciones para su correcta ordenación. Tras varias décadas de crecimiento urbano intenso se observa la dificultad que tienen los documentos de ordenación para regularlo y dirigirlo en los límites de la ciudad. Tan sólo las figuras de protección de espacios naturales aportan ciertas garantías de preservar determinados entornos. Las propuestas se concretan en la necesidad de resaltar el valor natural, de ocio y agrario del medio rural próximo. También se incide en la necesidad de acometer la ordenación de este espacio utilizando una metodología diferente, la mirada invertida, con el objeto de conseguir mayor consenso y respeto a las propuestas de todas las partes.
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In the first quarter of 1997 R.V. “Walther Herwig III” took part in the internationally (ICES) coordinated International Bottom Trawl Survey (IBTS) in the North Sea. A total of 365 half-hour tows using a standardized GOV-net were made by seven research vessels in order to determine the strength of incoming yearclasses of cod, haddock, whiting, Norway pout, herring, sprat, and mackerel. Overall results, though preliminary show a considerable increase of the index figures for cod, Norway pout, herring, and mackerel whereas the indices for haddock, sprat, and whiting indicate lower recruitment figures. Water temperatures and salinity values were unhomogeneously below and above of the longterm mean.
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Total world fishery production 1995, including aquaculture, of fish, shellfish, frogs and turtles – reached a new record of 112.9 million tones live weight. Marine fishery had a share of 91,9 million tonnes (+ 0.4) and freshwater fishery 21.0 million tonnes (+ 2.0). Not included in these figures are seals, whales, crocodiles and algae. Marine mammals and crocodiles are listed by number of killed individuals, and not given by weight. Algae alone represent a biomass of 7.1 million tonnes, but are not included by the FAO in the nominal „total production of the world“ either. About two thirds of the marine fishery harvest was used for human consumption, one third for industrial purposes – mainly production of fish meal and fish oil.
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In this reservoir, the parameters being assessed are very important in the aspect of fish culture. These parameters are: physical parameters which includes temperature (O), Transparency (M).Chemical parameters include: Dissolve oxygen (mg/l) pH concentration and the Biological Parameters which include phytoplankton and zooplankton. The phytoplankton and zooplankton identification and estimation were carried out in the NIFFR Limnology Laboratory, (Green House), New Bussa. Each identified zooplankton and phytoplankton species was placed according to its major group e.g. zooplankton was grouped into three families, Roifera, Cladocera and Copepods. During this study period it was observed that copepods have the highest total number of zooplankton both beside the poultry and monk (station 'A'&'B'). Water temperature of station 'A' (beside the poultry house) ranges from 27 C-29, 5 c also same station 'B' (near the monk). Dissolve oxygen station 'A' range from 6.30mg/l-7.40mg/l while that of station 'B' ranges from 6.20mg/7.50mg/l, turbidity reading of station A'ranges from 0.19m-0.3m while station 'B' ranges from 0.22m-0.37m. The last parameter, which is pH concentration, in both stations 8.2 was observed this is an indication that the pH was constant. According to some literature review all the water parameter figures obtained were good for fish culture
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From 25 November until 8 Deeember 1994, a sea-going workshop with the above title was carried out on board RV "Walther Herwig IlI" under the umbrella of the Baltie Marine Biologists (BMlJ) and the International Council for the Exploration of the Sea (ICES). Under the co-convenorship of the first two authors of this paper, 11 seientists from 8 of the 9 countries bordering the Baltic Sea (except Sweden) actively involved in research monitoring into fish diseases/parasites participated. The main reason for holding the workshop was that, although fish disease monitoring programmes on the abundance and spatial distribution of fish diseases/parasites are being carried out by some of the countries bordering the Baltic Sea, there is still a striking lack of seientific information as compared to other seas, such as the North Sea. Moreover, since new fish disease monitoring programmes have recently been started (mainly by the new Baltic republics Latvia and Estonia, which recently became ICES-member countries) or are planned for the near future (Lithuania), BMB as weil as ICES felt the need for a interealibration and standardization of methodologies applied during fish disease/parasite surveys for the specific conditions in the Baltic Sea. Therefore, the major objectives of the workshop were -to obtain information about the disease/parasite prevalence in Baltic (Platichthys flesus) and other abundant fish species along a transect from the western (Mecklenhurg Bight) to the eastern (Gulf of Finland) Baltic Sea to be used as a baseline for future studies, -to intercalibrate methodologies applied for sampling, diagnosis of diseases/parasites, reporting and analyses of disease data, -if necessary, to recommend standard methodologies to be used for fish disease/parasite monitoring programmes under the specific conditions in the Baltic Sea. Although the data have yet not been completely analyzed, there is indication for some pronounced spatial trends regarding the prevalence of certain diseases/parasites, mainly for Iymphocystis and skin ulcerations in flounder but also for diseases and parasites of cod (Gadus morhua) which can be seen in figures 2 and 4. Recommendations for standard methodologies will later be published elsewhere.
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The new German R.V. "Walther Herwig III" joined the International North Sea Bottom Trawl Survey (IBTS) coordinated in the frame or ICES from February 18 to March 22 1994. A total of 354 valid half hour tows were made by seven research vessels from the different ICES members in order to determine the strength of incoming year classes of commercially most important fish species. Preliminary index figures for the stocks under observation of all participating vessels show that only the North Sea sprat stock developed a substantial year class in 1993. In addition, hydrographic data were collected during the survey. These data show the temperatures and salinities of the northern and central North Sea in most parts beneath the mean values during the period under investigation.
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通过弱波导近似的方法,讨论了椭圆芯双模光纤中沿光纤长轴的基模模斑半径Wx和短轴的基模模斑半径Wy尺寸,分析了它们的比值随入射光波长λ及纤芯半长轴与半短轴的比值a/b的变化规律。 针对基模LP01和第一高阶模LP11间的相位差变化,计算了双模干涉模斑的分布结构。计算结果表明,当基模LP01和第一高阶模LP11间的相位差为π/2时,两瓣干涉模斑有相同的结构特征。同时,两瓣模斑的中心间距S随Wx/Wy的的增加而变大。而且,当入射波长在0.65 μm和 1.31 μm之间变化时,结合两瓣模斑的中心间距S随Wx/Wy的变化规律,首次给出了S的计算公式。这对于实际应用如传感器和光纤耦合器件设计是很重要的。
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35 p.