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| Registros recuperados: 75 | |
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| Deslous Paoli, Jean-marc. |
| Des prélèvements dans le bassin de Marennes-Oléron ont permis de localiser les fortes charges de Crepidula fornicata L. principalement dans le centre du bassin (le long du banc de Charret et dans le courant d'Oléron). En ces deux points la charge fraîche cumulée a été estimée à environ 2 700 tonnes. La structure de population fait apparaître une croissance moyenne de 20, 19, 17 et 12 millimètres respectivement pour les 1ère, 2ème, 3ème et 4ème années avec une variabilité très importante dès la première année. 74,5% des animaux constituent des chaines primaires d'en moyenne six individus fixés sur des coquilles de crépidules mortes. La période de reproduction s'étale vraisemblablement du mois d'avril au mois de septembre et 25% des individus portent des... |
| Tipo: Text |
Palavras-chave: Crepidula fornicata; Population; Croissance; Reproduction; Marennes Oléron. |
| Ano: 1982 |
URL: http://archimer.ifremer.fr/doc/00092/20356/18017.pdf |
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| Perga, Marie-elodie; Danger, Michael; Dubois, Stanislas; Fritch, Clementine; Gaucherel, Cedric; Hubas, Cedric; Jabot, Franck; Lacroix, Gerard; Lefebvre, Sebastien; Marmonier, Pierre; Bec, Alexandre. |
| The French National Institute of Ecology and Environment (INEE) aims at fostering pluridisciplinarity in Environmental Science and, for that purpose, funds ex muros research groups (GDR) on thematic topics. Trophic ecology has been identified as a scientific field in ecology that would greatly benefit from such networking activity, as being profoundly scattered. This has motivated the seeding of a GDR, entitled “GRET”. The contours of the GRET's action, and its ability to fill these gaps within trophic ecology at the French national scale, will depend on the causes of this relative scattering. This study relied on a nationally broadcasted poll aiming at characterizing the field of trophic ecology in France. Amongst all the unique individuals that fulfilled... |
| Tipo: Text |
Palavras-chave: Trans-ecosystem; Scientific network; Cleavage; Ecology; Population; Community. |
| Ano: 2018 |
URL: http://archimer.ifremer.fr/doc/00442/55338/56849.pdf |
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| Wilson, Jg. |
| Changes in the Tellina tenuis population in Dublin Bay, Ireland since 1977 are described. Population density at the monitoring site increased from 260 m(-2) (although a maximum density of 548 m(-2) was found nearby) in 1977 to a peak of 434 m(-2) in 1989. Densities recently have been the lowest recorded, around 170 m(-2). These changes do not seem to have been associated with any change in elevation of the site. The population structure has changed considerably, from one dominated by larger, older animals in 1977, when there did not seem to have been any significant recruitment for the previous two years, to one in which recruitment, if not in any great numbers, has at least been more or less regular, with the last two years (1993 and 1994) showing the... |
| Tipo: Text |
Palavras-chave: Tellina tenuis; Long-term; Population; Growth; Ireland. |
| Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/00093/20396/18063.pdf |
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| Morin, Jocelyne; Bertrand, Jacques; Cochard, Marie-laure; Coppin, Franck; Leaute, Jean-pierre; Lobry, Jeremy; Mahe, Jean-claude; Poulard, Jean-charles; Rochet, Marie-joelle; Schlaich, Ivan; Souplet, Arnauld; Trenkel, Verena; Vaz, Sandrine; Verin, Yves. |
| Since about twenty years, Ifremer have carried out fishery surveys along the French coasts. A dynamic indicator-based approach to the assessment of multi-stock fisheries has been applied to these data series. Reference points for non-commercial populations and community indicators are seldom available, but reference directions are well established: it is known whether fishing will increase or decrease the indicator, hence the direction that should be avoided. A set of simple indicators of fishing impacts on fish populations and communities were estimated from time-series data provided by scientific surveys (population abundance and average length, community total biomass and number, average length and weight, and size spectrum). Trends in these indicators... |
| Tipo: Text |
Palavras-chave: Communauté; Population; Indicateurs; Campagnes scientifiques; Pêcheries multi spécifiques; Approche écosystémique pour la gestion des pêches. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/rapport-7293.pdf |
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| Bayed, Abdellatif; Quiniou, Francoise; Benrha, Ali; Guillou, Monique. |
| The condition of three intertidal Paracentrotus lividus populations, which inhabit an area between Rabat and Casablanca (Morocco) known by its high wave energy and its substantial anthropogenic disturbances were described. The growth rate of the juvenile sea urchins in this intertidal zone was low compared with more sheltered populations. A sharp increase in the gonad index was observed between January and March at the beginning of a period of algal production, and was concomitant with increases in seawater temperature and food consumption rate. This gonad index increase was followed by a single spawning period occurring between March and June, probably triggered by the phytoplankton bloom induced by upwelling conditions. Larval development in all three... |
| Tipo: Text |
Palavras-chave: Moroccan Atlantic; Growth; Population; Juvenile; Reproduction. |
| Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-602.pdf |
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| Le Gall, Jean-yves; Bosc, Pierre; Taquet, Marc. |
| A research programm on the marine green turtle Chelonia mydas nesting on the two major reproduction sites for the species in the Indian Ocean, conducled over last 15 years, included intensive tagging programm. Processing of these lagging data provides estimations of adult female populations {or each site and season from two independent methods. First classical method is the ratio of total number of nests produced over a define time on the mean individual number of nests by female during the same time (November, December, January). The computed mean individual number ranges from 3 to 3.5 obtained over 2 to 3 months. The second method is the multiple capture-recapture method (JOLLY, 1965; SEBER, 1965; MANLY, 1984). Il is an original tentative of applying... |
| Tipo: Text |
Palavras-chave: Tortue verte; Chelonia mydas; Reproduckion; Ponte; Population; Femelles; Marquage; Recapture; Océan Indien.; Marine green turtle; Chelonia mydas; Capture; Recapture; Indian Ocean; Nesting; Populations; Tagging; Reproduction. |
| Ano: 1986 |
URL: http://archimer.ifremer.fr/doc/00113/22406/20103.pdf |
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| Diaz Almela, F; Boudry, Pierre; Launey, Sophie; Bonhomme, Francois; Lapegue, Sylvie. |
| The geographical structure of 15 natural populations of the flat oyster (Ostrea edulis L.) was assessed by single-strand conformation polymorphism (SSCP) of a 313-base-pair (bp) fragment of the mitochondrial 12S-rRNA gene. Fourteen haplotypes were observed, with one being dominant in the Mediterranean samples and another one in the Atlantic populations. The geographically extreme populations sampled in Norway and the Black Sea appeared differentiated by exhibiting the dominance of a third group of haplotypes. The results were compared to available microsatellite data at five loci. The Atlantic/Mediterranean differentiation pattern was qualitatively the same with both types of markers, confirming an isolation-by-distance pattern. The average mitochondrial... |
| Tipo: Text |
Palavras-chave: Ostrea edulis; Polymorphism; Flat oyster; Population; Gene. |
| Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/2004/publication-680.pdf |
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| Becheler, Ronan; Diekmann, O.; Hily, Christian; Moalic, Yann; Arnaud-haond, S.. |
| Seagrasses structure some of the world's key coastal ecosystems presently in decline due to human activities and global change. The ability to cope with environmental changes and the possibilities for shifts in distribution range depend largely on their evolvability and dispersal potential. As large-scale data usually show strong genetic structure for seagrasses, finer-grained work is needed to understand the local processes of dispersal, recruitment and colonization that could explain the apparent lack of exchange across large distances. We aimed to assess the fine-grained genetic structure of one of the most important and widely distributed seagrasses, Zostera marina, from seven meadows in Brittany, France. Both classic population genetics and network... |
| Tipo: Text |
Palavras-chave: Clonality; Dispersal; Ecotype; Network analysis; Population; Zostera marina. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00006/11690/8499.pdf |
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| Marto,Vanilcia Clementino de Oliveira; Akama,Alberto; Pelicice,Fernando Mayer. |
| Cichla piquiti is endemic to the Tocantins-Araguaia river basin, but information about its biology is restricted to populations introduced in other basins. In order to fill this gap, we investigated the feeding ecology and reproductive dynamics of C. piquiti in Lajeado reservoir, rio Tocantins. A total of 270 fish were collected between November 2010 and October 2011. The diet is rich and composed of at least 23 resources, predominantly fish (at least 19 species). We observed no clear influence of sex, periods and ontogeny on diet, which was basically composed of Characidae and Cichlidae. Considering its reproductive dynamics, immature, reproductive and non-reproductive fish were recorded during the whole study, and reproductive effort did not differ among... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Diet; Management; Population; Predator; Recruitment. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252015000300625 |
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| 柳川, 久; 澁谷, 辰生; Yanagawa, Hisashi; Shibuya, Tatsuo. |
| 1.北海道十勝管内の２か所の小学校で，建物の周辺環境（植生や人工建造物），鳥類相と衝突死する鳥類の個体数の関係を調べるため，1994年６月から12月まで調査を行なった．調査を行なった新得町立屈足小学校と佐幌小学校はガラスを多用した同型の体育館を有していた． 2.ラインセンサスの結果，屈足小学校では25種498個体，佐幌小学校では25種516個体の鳥類が観察された．屈足小学校では，スズメが最も多く（178個体. 2000. 35.7％），次いでコムクドリ（58個体. 2000. 11.6％），アオジ（53個体. 2000. 10.6％），ハクセキレイ（50個体. 2000. 10.0％）が多かった．佐幌小学校ではスズメ（152個体. 2000. 29.5％）が最も多く，次いでシメ（78個体. 2000. 15.1％）が多かった． 3.佐幌小学校では10種26個体のガラス衝突した鳥類が拾得されたが，屈足小学校では１個体のみであった．衝突死が最も多い鳥類はシメで11個体（40.7％）であった．死亡した鳥類はほとんど（85.2％）が幼鳥であった． 4.佐幌小学校の周辺では，巣立ちしたシメの幼鳥の群れが採食するのがしばしば観察された．また，佐幌小学校にはスズメ類やムクドリ類のための巣箱も架設されており，ホオジロ類が好むやぶ地も備わっていた． 5.両校間の衝突死個体数の差は，特にシメなどの建物周辺で繁殖，採餌する鳥類の個体数の違いに起因すると思われた． |
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Palavras-chave: ガラス衝突; 死因; 鳥類群集; Bird; Hokkaido; Mortality; Population; Window-collisions. |
| Ano: 2000 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2300 |
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| von Braun, Joachim; de Haen, Hartwig; Blanken, Juergen. |
| Rapid population growth in agroecologies that are already under high population pressure poses a major challenge for development policy. It becomes an even greater challenge in complex agroecologies where little new technology for rapid agricultural expansion is available. The mountain zones of the Zaire-Nile Divide in Central Africa present an example of such a challenging environment where agriculture has encroached onto marginal zones, that is, water catchment areas and the last tropical forests of the area. This study by von Braun, de Haen, and Blanken highlights the potentials of agricultural development for the employment, income, and consumption of the poor, but also stresses that nonagricultural rural growth and employment expansion are key to... |
| Tipo: Report |
Palavras-chave: Agriculture and State; Rwanda; Produce trade; Government policy; Exports; Food supply; Nutrition policy; Population; Food Consumption/Nutrition/Food Safety; International Development. |
| Ano: 1991 |
URL: http://purl.umn.edu/42154 |
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| Registros recuperados: 75 | |
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