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| Registros recuperados: 10 | |
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| Medernach, L; Gremare, A. |
| We compared the ability of three direct methods (increment summation, loss summation and instantaneous growth rate coefficient), the size-frequency method, and eight indirect methods (Banse and Mosher, Benke, Brey, Edgar, Morin and Bourassa, Plante and Downing, Robertson and Schwinghamer et al.) to measure or to predict the secondary production of a Mediterranean population of the polychaete Ditrupa arietina. This comparison was carried out both on the 1994 cohort during its two-year lifespan and on the entire population during the two years of the study (1994-1996). Our results showed that all three direct methods are more or less equivalent. Results referring to the year 1994-1995 showed a strong overestimation of the actual production by the size... |
| Tipo: Text |
Palavras-chave: Production secondaire; Méthodes; Polychètes; Méditerranée; Secondary production; Methods; Polychaetes; Mediterranean Sea. |
| Ano: 1999 |
URL: http://archimer.ifremer.fr/doc/00325/43614/43916.pdf |
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| Montiel, Américo; Andrade, Claudia; Quiroga, Eduardo. |
| El gastrópodo carnívoro Trophon geversianus (Pallas, 1774) es una de las especies bentónicas explotadas comercialmente en la región de Magallanes, de la cual no existe información relacionada a su productividad biológica. En este trabajo, se estimó la producción secundaria y productividad de una población intermareal de T. geversianus a través del modelo de redes neurales. Los muestreos se realizaron estacionalmente en Bahía Laredo, estrecho de Magallanes entre los meses de agosto 2007 y abril 2008. La longitud de los ejemplares de T. geversianus fluctuó de 12,4 a 55,4 mm (28,4 ± 7,4). La población presentó una distribución unimodal. Las densidades medias estacionales oscilaron entre 0,23 ind m-2 y 0,97 ind m-2, mientras que la biomasa media varió entre... |
| Tipo: Journal Contribution |
Palavras-chave: Marine molluscs; Secondary production; Biological production; Gasterosteidae; Muricidae; Http://aims.fao.org/aos/agrovoc/c_41671; Http://aims.fao.org/aos/agrovoc/c_47299. |
| Ano: 2009 |
URL: http://hdl.handle.net/1834/4169 |
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| Valle, M.; Fuentes, M.. |
| Del 28 de agosto al 11 de septiembre de 2013 y del 7 al 21 de enero de 2014 se realizaron dos campañas de investigación a bordo del B/I Octopussy con el objetivo de establecer la distribución y variación de los valores de productividad primaria (fitoplancton) y secundaria (zooplancton), a dos profundidades, obteniéndose muestras planctónicas en 61 estaciones planctónicas distribuidas en cinco macrozonas que abarcan el Mar Territorial y Aguas Interiores de la Plataforma Continental del Ecuador. Se obtuvieron muestras para la determinación cualitativa y cuantitativa del fitoplancton y zooplancton mediante botellas Van Dorn (0 y 15 m) y mediante arrastres superficiales y verticales con redes de 60 y 200 μm de luz de malla según el caso. También se obtuvieron... |
| Tipo: Report |
Palavras-chave: Primary production; Secondary production; Zoopláncton; Fitopláncton. |
| Ano: 2014 |
URL: http://hdl.handle.net/1834/5462 |
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| Aronés, Katia; Grados, Daniel; Ayón, Patricia; Bertrand, Arnaud. |
| Anchovy (Engraulis ringens) is the most important exploited fish species in the Northern Humboldt Current System (NHCS) off Peru. This species, as well as most other pelagic resources, mainly forage on zooplankton. The NHCS is bottom-up controlled at a variety of scales. Therefore, fish biomass is driven by the abundance of their prey. In this context, we studied the spatiotemporal patterns of zooplankton biomass in the NHCS from 1961-2012. Data were collected with Hensen net all along the Peruvian coast. To transform zooplankton biovolume into biomass we used a regression that was calibrated from 145 zooplankton samples collected during four surveys and, for which, precise information was available on both biovolume and wet weight. The regression model... |
| Tipo: Text |
Palavras-chave: Secondary production; Mesozooplankton; Macrozooplankton; Regime-shift; Spatiotemporal distribution; Decadal trends. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00588/70042/67972.pdf |
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| Herman, P.M.J.; Heip, C.H.R.; Vranken, G.. |
| The ostracod <i>Cyprideis torosa</i> Jones,1985 is a dominant species in the meiofauna of brackish water habitats. Its production in the field over a five-year period has been calculated using two production models. The first model uses the age-distribution of shells preserved in the sediment to assess the stage-specific mortality rates and the stage durations. The second model is the size-frequency model, modified for use with development stages instead of size-classes. Productions calculated with both methods agree very well. Their values are 9.7 and 9.2 g dwt.m<sup>-2</sup>y<sup>-1</sup> respectively. The yearly P/B-ratio is 2.7 or 2.6y<sup>-1</sup>, production efficiency P/A is 0.38 or 0.37. The... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Secondary production; Cyprideis torosa. |
| Ano: 1983 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3396 |
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| Registros recuperados: 10 | |
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