73 resultados para 164-993

em Aquatic Commons


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Representatives from the family of Lemnaceae (duckweed) make ideal experimental material for research into a succession of phytophysiological processes with regard to growth rate and vegetative reproduction. They are also easy to maintain in sterile cultures. Lemnaceae belong to the higher flowering plants (flowers are rarely produced), however they are distinguished by a much simplified morphological and anatomical structure. As water plants they possess the advantage, that they can be cultivated in synthetic media under laboratory conditions controlled by the application of both a known light intensity and temperature. This paper describes experimental research of growth of Lemnaceae in different conditions. Some of the variables were mineral media, illumination and aeration.

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When flow returns to a temporary stream a certain number of plant and animal species establish themselves more or less rapidly on the stream-bed constituting the initial phase of evolution of the re-population. This phase is essentially characterised by the ”awakening” of animal species that passed the dry season in a dormant state and by the development of the first unicellular algae that constitute the periphyton. Then they are succeeded by more or less stable animal groups and the structural complexity increases. The authors of the present study aim to analyse the dynamics of community succession from the return of water to the biotope until its drying up. It is attempted to determine the influence of the duration of flow on this evolution. This work is based on the analysis of population diversity with reference to its two complementary aspects, species richness and equitability. The River Destel which was studied for this project is situated in the Gorge of Ollioules near the town of Toulon.

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Report of Opening Session (pdf 58 KB) Report of Governing Council Meeting (pdf 244 KB) Report of 2003 interim Governing Council meeting Tenth Anniversary PICES Organization Review Report of the Finance and Administration Committee (pdf 102 KB) 2002 Auditor's report to the Organization Review of PICES Publication Program Reports of Science Board and Committees: Science Board/Governing Council interim meeting (pdf 81 KB) Science Board (pdf 95 KB) Study Group on PICES Capacity Building Biological Oceanography Committee (pdf 65 KB) Advisory Panel on Micronekton sampling gear intercalibration experiment Advisory Panel on Marine birds and mammals Fishery Science Committee (pdf 41 KB) Working Group 16 on Climate change, shifts to fish production, and fisheries management Marine Environmental Quality Committee (pdf 76 KB) Working Group 15 on Ecology of Harmful Algal Blooms (HABs) in the North Pacific Physical Oceanography and Climate Committee (pdf 70 KB) Working Group 17 on Biogeochemical data integration and synthesis Advisory Panel on North Pacific Data Buoy Technical Committee on Data Exchange (pdf 32 KB) Implementation Panel on the CCCC Program (pdf 64 KB) Nemuro Experimental Planning Team (NEXT) BASS Task Team (pdf 35 KB) Advisory Panel on Iron Fertilization Experiment MODEL Task Team (pdf 29 KB) MONITOR Task Team (pdf 30KB) REX Task Team (pdf 25 KB) Documenting Scientific Sessions (pdf 164 KB) List of Participants (pdf 60 KB) List of Acronyms (pdf 21 KB)

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This report presents discharge, chemical analyses, temperatures, and specific conductance records collected at 25 surface-water sites and chemical analyses of ground water, well descriptions and records of ground-water levels collected at 164 ground-water sites. It also contains 35 logs of the sedimentary rocks penetrated in the drilling of wells and test borings ranging in depth from 147 to 625 feet. These hydrologic data were collected as part of an investigation of the water resources of the county. The interpretative results of the investigation are in the report entitled, "Water resources of Walton County," by C. A. Pascale (in preparation, 1971). (108 page document)

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The Biscayne Bay Benthic Sampling Program was divided into two phases. In Phase I, sixty sampling stations were established in Biscayne Bay (including Dumfoundling Bay and Card Sound) representing diverse habitats. The stations were visited in the wet season (late fall of 1981) and in the dry season (midwinter of 1982). At each station certain abiotic conditions were measured or estimated. These included depth, sources of freshwater inflow and pollution, bottom characteristics, current direction and speed, surface and bottom temperature, salinity and dissolved oxygen, and water clarity was estimated with a secchi disk. Seagrass blades and macroalgae were counted in a 0.1-m2 grid placed so as to best represent the bottom community within a 50-foot radius. Underwater 35-mm photographs were made of the bottom using flash apparatus. Benthic samples were collected using a petite Ponar dredge. These samples were washed through a 5-mm mesh screen, fixed in formalin in the field, and later sorted and identified by experts to a pre-agreed taxonomic level. During the wet season sampling period, a nonquantitative one-meter wide trawl was made of the epibenthic community. These samples were also washed, fixed, sorted and identified. During the dry season sampling period, sediment cores were collected at each station not located on bare rock. These cores were analyzed for sediment size and organic composition by personnel of the University of Miami. Data resulting from the sampling were entered into a computer. These data were subjected to cluster analyses, Shannon-Weaver diversity analysis, multiple regression analysis of variance and covariance, and factor analysis. In Phase II of the program, fifteen stations were selected from among the sixty of Phase I. These stations were sampled quarterly. At each quarter, five Petite Ponar dredge samples were collected from each station. As in Phase I, observations and measurements, including seagrass blade counts, were made at each station. In Phase II, polychaete specimens collected were given to a separate contractor for analysis to the species level. These analyses included mean, standard deviation, coefficient of dispersion, percent of total, and numeric rank for each organism in each station as well as number of species, Shannon-Weaver taxa diversity, and dominance (the compliment of Simpson's Index) for each station. Multiple regression analysis of variance and covariance, and factor analysis were applied to the data to determine effect of abiotic factors measured at each station. (PDF contains 96 pages)

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ENGLISH: A primary objective of the Inter-American Tropical Tuna Commission is a knowledge of the ecology of tunas which inhabit the Eastern Tropical Pacific. This paper presents some results of the work in physical oceanography, which, it is hoped, will be useful to the biological work and at the same time of interest to physical oceanographers. The work presented here was begun in connection with simple observable facts; the thermocline is very close to the sea surface in a region off Costa Rica (Wooster and Cromwell, 1958), and this region is biologically productive (Holmes, et al. 1957; Brandhorst, 1958). It is the main object of this study to describe and explain these facts, insofar as possible. SPANISH: Uno de los principales objetivos de la Comisión Interamericana del Atún Tropical es el conocimiento de la ecología de los atunes que viven en el Pacífico Oriental Tropical. Este informe presenta algunos de los resultados del estudio en oceanografía física, los cuales se espera que serán útiles en la investigación biológica y, al mismo tiempo, de interés para los oceanógrafos físicos. El trabajo presentado aquí se inició en conexión con sencillos hechos observables; mar afuera de Costa Rica, la termoclina queda muy cerca de la superficie del mar (Wooster y Cromwell, 1958) y esta región es biológicamente productiva (Holmes, el al., 1957; Brandhorst, 1958). El objeto principal de este estudio es describir y explicar estos hechos, hasta donde sea posible. (PDF contains 32 pages.)

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This report contains the frrst observations made for the Modis Optical Characterization Experiment (MOCE). Data presented here were obtained on the R/V DeSteiguer between 28 August and 8 October along the central California coast and in Monterey Bay. Three types of data are reported here: high spectral resolution radiometry at three depths for seven stations; salinity, temperature, fluorescence and beam attenuation profiles at the same stations; and total suspended matter and suspended organic carbon and nitrogen. [PDF contans 164 pages]

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The Alliance for Coastal Technologies (ACT) Workshop entitled, "Biological Platforms as Sensor Technologies and their Use as Indicators for the Marine Environment" was held in Seward, Alaska, September 19 - 21,2007. The workshop was co-hosted by the University of Alaska Fairbanks (UAF) and the Alaska SeaLife Center (ASLC). The workshop was attended by 25 participants representing a wide range of research scientists, managers, and manufacturers who develop and deploy sensory equipment using aquatic vertebrates as the mode of transport. Eight recommendations were made by participants at the conclusion of the workshop and are presented here without prioritization: 1. Encourage research toward development of energy scavenging devices of suitable sizes for use in remote sensing packages attached to marine animals. 2. Encourage funding sources for development of new sensor technologies and animal-borne tags. 3. Develop animal-borne environmental sensor platforms that offer more combined systems and improved data recovery methodologies, and expand the geographic scope of complementary fixed sensor arrays. 4. Engage the oceanographic community by: a. Offering a mini workshop at an AGU ocean sciences conference for people interested in developing an ocean carbon program that utilizes animal-borne sensor technology. b. Outreach to chemical oceanographers. 5. Min v2d6.sheepserver.net e and merge technologies from other disciplines that may be applied to marine sensors (e.g. biomedical field). 6. Encourage the NOAA Permitting Office to: a. Make a more predictable, reliable, and consistent permitting system for using animal platforms. b. Establish an evaluation process. c. Adhere to established standards. 7. Promote the expanded use of calibrated hydrophones as part of existing animal platforms. 8. Encourage the Integrated Ocean Observing System (IOOS) to promote animal tracking as effective samplers of the marine environment, and use of animals as ocean sensor technology platforms. [PDF contains 20 pages]

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Im Oktober/November des vergangenen Jahres ergab sich während der 483. Reise von FK „Solea“ ein im Vergleich zu den vier Vorjahren hoher Fangindex von 220 Kabeljau Gadus morhua je Stunde (Weber 2001). Die Fische hatten eine Länge von 15 bis18 cm und waren besonders in Küstennähe Ostfrieslands anzutreffen. Durch unsere Langzeituntersuchungen zur Ökologie der Flussseeschwalbe Sterna hirundo im Wattenmeer sind wir bereits im Juni des Jahres 2001 auf den starken Jahrgang des Kabeljaus aufmerksam geworden und können die Vermutung von Weber bestätigen, dass die Kabeljaus den Sommer über im Wattengebiet herangewachsen sind.

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Several fishery independent estimates of the year-class strength are necessary for the assessment and the management of the total fish stock. An index for the year-class strength of the spring spawning herring in the western Baltic Sea is estimated on the basis of larvae surveys in the most important spawning ground. The results indicate a weak year-class 2001.

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Individuals of the western stock of Baltic cod were kept at captivity with different temperatures and salinities until natural spawning. Spawning activities up to 16 weeks were observed between February and June. This time interval agrees weIl with the spawning season of the wild cod stock. Also as in in-situ observations larger individuals started earlier with the spawning process than smaller ones and had significantly larger periods of spawning. Larger cods produced more batches and more eggs than smaller cods within this time interval. The comparison between the actual and potential absolut fecundity showed large differences. Only apart of the potential absolut fecundity, estimated in the phase of prespawning development of ovaries, was developed until their release. These analyses showed that larger cod were able to develop a larger part of the eggs within the ovaries up to the complete development. This result should be considered in the future during estimations of the population fecundity of the western Baltic spawning stock.

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Some aspects of the reproduction of Nematopalaemon hastatus in the artisanal shrimp fishery in the outer Cross River estuary (Nigeria) was investigated. 2 kg samples were taken from the daily catch of the N. hastatus fishery on a twice-weekly basis. The N. hastatus in the sample were then observed for gravidity, using a hand lens, and their post-orbital carapace length (POCL) taken. This was done over a 12-month period. The eggs in formalin-fixed samples showed colour changes from light orange to dark brown with maturation. Gravid females with eggs in different stages of maturation, from light orange to dark brown were observed in the samples. The reproduction occurs all year-round. The proportion of gravid females observed in samples had two distinct peaks in June and November, and two distinct troughs in May and October. The lowest length at which gravidity was observed was 6.0 mm POCL. There were no Penaeus notialis in the samples

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Information is given on the landings of herring and sprat in the Skagerrak/Kattegat and Baltic Sea. Based on assessment units used by the ‘Herring Assessment Working Group for the Area South of 62° N’ and the ‘Baltic Fisheries Assessment’ working group, the total landings are shown for the years 1974 to 1996. Further the quarterly landings for 1996 are listed on national basis by area/Sub-Division. In addition an actual description of the national fleets operating in the Skagerrak/Kattegat and Baltic Sea is given. At least the actual stock development and the catch options estimated by the corresponding working groups for different assessment units is presented.