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Selected AbstractsThe effect of the sampling scale on zooplankton community assessment and its implications for the conservation of temporary ponds in south-west SpainAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 2 2007Khalid Fahd Abstract 1.The zooplankton (rotifer and microcrustacean) assemblages of temporary ponds in the Doñana National Park (south-west Spain) have been compared in two surveys of contrasting scales that resulted in the same number of samples: an extensive survey of 36 ponds sampled in May 1998 (or widespread survey) and a survey of nine ponds sampled four times over 2 years (or cumulative survey). 2.The total number of microcrustacean and rotifer taxa was larger in the cumulative survey (43 and 41 taxa, respectively) than in the widespread survey (39 and 34, respectively). Crustacean assemblages became less alike throughout the cumulative survey. 3.The presence of invertebrates (Coleoptera, Odonata, Heteroptera and crayfish) and aquatic vertebrates (fish and salamanders) was recorded as an estimate of potential predator impact on zooplankton. Several pond features (water depth, conductivity, pH, chlorophyll a concentration, distance to the nearest permanent pond and to the marsh) were also measured in both surveys. 4.A combination of these environmental factors was more strongly related to the similarity matrices derived from the zooplankton assemblages of the cumulative survey (Rho=0.7) than to those of the widespread survey (Rho<0.4). The distance of ponds to the marsh was an important factor in explaining this correlation as well as the strongest factor in the ordination of crustacean assemblages following a CCA. 5.Predation by exotic fish in long-hydroperiod ponds where overflow drains to the nearby marsh (fish source) is the mechanism likely to explain the changes in crustacean composition recorded in the cumulative survey. 6.The cumulative survey was more suitable for the study of zooplankton diversity as it rendered a higher number of taxa and gave more insight into the mechanisms that explain taxon richness. Thus, conservation strategies in temporary habitats require a scale of observation that includes long temporal changes. Copyright © 2006 John Wiley & Sons, Ltd. [source] Partisan responses to Europe: Comparing Finnish and Swedish political partiesEUROPEAN JOURNAL OF POLITICAL RESEARCH, Issue 2 2001KARL MAGNUS JOHANSSON This article analyzes party responses to European integration in Finland andSweden. We argue that such responses are shaped by seven explanatory factors: basic ideology, public opinion, factionalism, leadership influence, party competition, transnational links, and the development of integration. Each factor can lead to a positive or a negative evaluation of the European Union. In the empirical analysis, the sample includes all parties represented in the respective national parliaments, and the research material consists of party documents, parliamentary votes, statements by leading party figures, public opinion surveys, direct observation and interviews. Party competition and leadership influence are the strongest factors in the Finnish case, while public opinion and factionalism are the strongest factors in Sweden. Issue avoidance combined with the secondary importance of the EU in party politics explain why parties have been relatively successful in containing internal factionalism and discord, especially in Finland. [source] Factors influencing fish catch levels on Kenya's coral reefsFISHERIES MANAGEMENT & ECOLOGY, Issue 4 2007S. C. Mangi Abstract, The factors influencing fish catches on Kenya's coral reefs were studied. Catch data were collected at the species level by counting the number of fish landed at each landing site of each fishing ground. Live coral cover, topographic complexity, fish and sea urchin density, and the number of fishers and gear units used in each fishing ground were compared with catch data. Fishing grounds included one location where only basket traps were allowed, six locations where all gear types were used except beach seines, and three locations where all types of gear, including beach seines, were used. Catch and effort variables were similar across the fishing grounds whereas live coral cover and sea urchin density differed (P < 0.01). The sites fished by all types of gear including beach seines had the lowest coral cover (8.4 ± 0.9%) and topographic complexity (1.12 ± 0.01). Catch levels were positively correlated with the number of fishers and fish density but not with the number of gear units deployed or sea urchin density. The number of fishers and live coral cover were the strongest factors determining total catch levels. The results suggest that high levels of fishing effort coupled with the use of destructive gear types, exacerbate the effects of overfishing on Kenya's reefs. [source] Factors associated with suicidal behaviors in a large French sample of inpatients with eating disordersINTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 7 2007Valérie J. Fedorowicz MDCM Abstract Objective: The objective of the present study was to identify factors associated with suicidal behaviors among patients with eating disorders. Method: A large database including sociodemographic and clinical characteristics of 1,009 consecutive patients hospitalized for an eating disorder in Paris, France, was examined. Data gathered upon admission to hospital were analyzed to identify factors associated with a history of suicide attempt or current suicidal ideation, among the whole sample as well as among each subtype of eating disorder. Results: Among the whole sample, the factor most strongly associated with suicide attempt or suicidal ideation was the diagnostic category, with the highest odds ratio for bulimia nervosa followed by anorexia nervosa of the binging/purging subtype. Among diagnostic subgroups, the strongest factors were drug use, alcohol use, and tobacco use. Conclusion: Suicide risk should be monitored carefully among patients with eating disorders, paying particular attention to combinations of risk factors. © 2007 by Wiley Periodicals, Inc. Int J Eat Disord 2007 [source] Can invasion patches of Acacia mearnsii serve as colonizing sites for native plant species on Réunion (Mascarene archipelago)?AFRICAN JOURNAL OF ECOLOGY, Issue 3 2009J. Tassin Abstract There is need for documenting the long-term effects of plant invasions at the landscape scale. We investigated the possible catalytic effect of invasive Acacia mearnsii De Wild. on the colonization of rural landscapes by native plant species on Réunion Island (Mascarene Archipelago, Indian Ocean). Data were recorded from 182 circular plots of 50 m2 within a set of 48 large invasion patches, aged from 1 to 48+ years. Only eighteen native plant species were present in the invaded patches and these in only 21 of the 48 patches. The Acacia invasion patches colonized by native flora were older and closer to the closest forest remnant. Most invasion patches colonized by native species were located <200 m from forest remnants. Results are consistent with studies on colonization rates of nonindigenous forest plantations, which increase with age and decrease with distance to seeds sources. Yet, the rate of Acacia invasion patches colonized by native flora remained very low compared to studies on the colonization of exotic plantations in other tropical countries. We conclude that invasion patches of Acacia mearnsii are poor colonizing sites for native plant species. Allelopathy is suspected as one of the strongest factors, which prevent this colonization. Résumé Il est nécessaire de documenter les effets à long terme des invasions de plantes à l'échelle du paysage. Nous avons étudié l'effet potentiellement catalyseur de la plante invasive Acacia mearnsii De Wild. sur la colonisation de paysages ruraux par des espèces végétales natives sur l'île de la Réunion (archipel des Mascareignes, océan Indien). On a récolté des données sur 182 parcelles circulaires de 50 m2 dans un ensemble de 48 grandes zones envahies âgées de un à plus de 48 ans. Il n'y avait que 18 espèces végétales natives dans les endroits envahis, et celles-là ne se trouvaient que dans 21 des 48 zones. Les zones envahies par les Acacia qui étaient colonisées par des espèces natives étaient plus âgées et se situaient plus près des reliquats forestiers les plus fermés. La plupart des zones envahies colonisées par des espèces natives étaient situées à moins de 200 m de forêts relictuelles. Les résultats sont cohérents avec des études sur les taux de colonisation de plantations forestières non indigènes, qui augmentent avec l'âge et diminuent avec la distance de la source des semences. Ceci dit, le taux de zones envahies par les acacias qui sont colonisées par la flore indigène reste très faible en comparaison avec les études sur la colonisation de plantations exotiques dans d'autres pays tropicaux. Nous concluons que les zones d'invasion d'Acacia mearnsii sont des sites de colonisation médiocre pour les espèces végétales indigènes. On suspecte que l'allélopathie est un des facteurs les plus actifs dans la prévention de cette colonisation. [source] | ||||||||||