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Laboring Through Uncertainty : an ethnography of the Chinese state, labor NGOs, and developmentPan, Darcy January 2016 (has links)
This study sets out to understand how international development projects supporting labor activism work in contemporary China. It focuses on the lived experiences of and relationships among a group of grassroots labor NGOs in the province of Guangdong, South China; intermediary NGOs in Hong Kong; and Western funding agencies that try to bring about social change in postsocialist China where the political climate is still highly restrictive and the limits of the state’s tolerance for activism are ambiguous and uncertain. Foregrounding the notion of uncertainty, this study investigates how state control is exercised by examining a specific logic of practices, discourses, and a mode of existence that constantly mask and unmask the state. More specifically, this study explores how the uncertainty about the boundaries of permissible activism is generative of a sociopolitical realm in which variously positioned subjects mobilize around the idea of the state, which in turn leads to articulations and practices conducive to both self-censorship and a contingent space of activism. Viewed as such, the idea of uncertainty becomes an enabler through which certain kinds of practices, relationships, and networks are made possible and enacted, and through which a sociopolitical realm of intimacy is constituted by and constitutive of these relationships, networks, and practices. Situated in the domain of uncertainty, this study examines the ways in which uncertainty, both as an analytical idea and an ontological existence, produces an intimate space where labor activists not only effectively self-censor but also skillfully map the gray zone between the relatively safe and the unacceptably risky choices.
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The effects of herring gulls (Larus argentatus) on the vegetation and soils of their nesting sites /Bays, Nathalie. January 1997 (has links)
This study was initiated to determine the effects of Herring Gulls (Larus argentatus) on the vegetation and soils of their nesting sites within the Mingan Island National Park Reserve. Both vegetation (species composition, cover, density, growth) and soil characteristics (pH, N, P, K, Ca, Mg) were monitored throughout the 1995 breeding season. Exclosures were installed within the colonies as control sites to prevent gull activity and these were compared to "treatment plots" or areas where gulls were present. All plants located at the study sites were native perennials with the exception of Stellaria, a native annual. Ledum groenlandicum was the only plant species significantly affected by gull activities. Both % cover and shoot growth for Ledum were greater in the exclosures than in the treatment plots over the breeding season. The gulls were also found to significantly increase pH and phosphorous levels in the soil through the deposition of faeces. Gull roosting sites were found to have higher nutrient levels than the nesting areas (treatment plots). The gulls appear to have minor effects over the short term, however the increases in soil nutrients may lead to significant changes over the long term. It is therefore imperative the exclosures remain in place to monitor for any long term changes which may occur.
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The effects of herring gulls (Larus argentatus) on the vegetation and soils of their nesting sites /Bays, Nathalie. January 1997 (has links)
No description available.
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The impact of human disturbance on the nesting success of the common eider Somateria mollissima /Bolduc, François. January 1998 (has links)
The influence of human disturbance on the nesting success of the Common eider (Sonateria mollissima) was investigated in the Mingan Archipelago National Park Reserve during summers of 1994 to 19%. Six colonies were used, four located on open islets and two on forested islands. Three experimental treatments were used that entailed varying the frequency and time occurrence of visits in incubation. Every years, each treatment was applied to several eider colonies differing in the density of nesting gulls on the same island. During visits, incubating females were flushed and nest fate recorded. Several variables also were measured during visits describing female quality (assessed by clutch size and laying date) and nest site quality (assessed by nest concealment, distance to shore, vegetation height, and density of nesting gulls on the island). Results showed that frequency of visits did not affect nesting success of eiders, mainly because most observed nest failures occurred after the first visit The time occurrence of the first visit during incubation was of primary importance; eider nests visited early were much more affected by our presence. The nesting success of eiders was related to the density of associated colonies of nesting gulls only when visits occurred during early incubation. Female eiders of greater reproductive quality were those most successful when disturbed regularly. These females were in greater proportion on islands associated with lower density of nesting gulls, i.e., on forested islands rather than on open islets. Within colonies, they were mainly found nesting near shore where nest concealment is sparse. Results showed that visits to eider colonies can greatly affect their reproductive output. Visits during early incubation on open islets had the greatest impact.
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Diet and reproductive success of herring gulls nesting on the middle north shore of the Gulf of St. LawrenceBoyne, Andrew. January 1999 (has links)
Breeding biology and diet of Herring Gulls Larus argentatus were studied on Ile Nue, in the Mingan Archipelago National Park Reserve, in the Gulf of St. Lawrence. Nesting parameters were measured 1994--1996, and fledging success and diet were followed in 1996. Clutch size was low in all three years of the study, and hatching success was low in 1995. Low clutch size and hatching success could not be explained by researcher disturbance, predation, or competition for nest sites, leaving food-stress as the most likely explanation. To reduce the biases associated with determining diet, we used four methods to estimate diet. The 1996 breeding season was divided into three periods using changes in the number of gulf pellets collected from roost sites as an indirect measure of dietary changes; these periods corresponded to the pre-spawning, spawning, and post-spawning periods of capelin Mallotus villosus. (Abstract shortened by UMI.)
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Diet and reproductive success of herring gulls nesting on the middle north shore of the Gulf of St. LawrenceBoyne, Andrew. January 1999 (has links)
No description available.
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The impact of human disturbance on the nesting success of the common eider Somateria mollissima /Bolduc, François. January 1998 (has links)
No description available.
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Recul de la lande à lichens de l'île Nue : déterminants et impacts sur la communauté végétaleMassé, Valérie 24 April 2018 (has links)
Les peuplements lichéniques sont très sensibles aux perturbations et au développement d’un couvert végétal vasculaire, étant incapables de rivaliser pour l’accès à la lumière et aux nutriments du sol. Cette étude s’intéresse à l’évolution de la lande à lichens de l’île Nue dans la Réserve de Parc National du Canada de l’Archipel-de-Mingan, soit dans un contexte insulaire méridional et en présence de perturbations par les goélands argentés. L’analyse de photographies aériennes a permis de mesurer un recul de 85,5 % de la superficie occupée par le lichen de 1967 à 2009. Les espèces responsables de ce recul sont principalement des arbustes (~63 %, Rhododendron groenlandicum et Empetrum nigrum) et des herbacées (~35 %, Rubus idaeus et Chamerion angustifolium). Ce recul de la lande à lichens ne semble pas associé aux récents changements climatiques puisqu'il était plus important entre 1967-1988 qu'entre 1988-2009, soit avant qu’un léger réchauffement soit observé dans la région. De plus, le faible couvert lichénique mesuré autour des sites perturbés par les goélands indique que les perturbations sont probablement survenues après le remplacement du lichen par des espèces vasculaires, ce qui suggère que ces perturbations ne sont pas responsables du recul observé. Les perturbations par les goélands semblent toutefois favoriser le développement d’un couvert herbacé. Outre la perte au niveau des espèces lichéniques, aucun effet négatif du développement d'un couvert végétal vasculaire sur la diversité, la richesse spécifique et l’abondance des groupes fonctionnels n'a été observé. Nos résultats ne permettent donc pas de déterminer la cause du recul de la lande à lichens. Un changement des conditions édaphiques, suite à l’accumulation de matière organique depuis l’émergence des îles, et la dégradation progressive du pergélisol pourraient être responsable du changement de végétation observé, bien que des études soient nécessaires pour vérifier ces hypothèses. / Because they are unable to compete for light and soil nutrients, lichens are sensitive to disturbance and to the development of a vascular plant cover. As such, the objective of this study was to better understand changes in the dynamics of lichen barrens found on île Nue in the Mingan Archipelago National Park Reserve of Canada, where recent increase in vascular plant cover was observed. Specifically, we aimed to evaluate the role of recent climate warming and herring gull disturbance on the lichen barrens’ recession on this island. Aerial photo analysis showed that the area occupied by lichen barrens declined by 85.5 % from 1967 to 2009, and that it was associated with an advance of vascular plants. The vascular plant species involved in this phenomenon were mainly shrubs (~63 %, Rhododendron groenlandicum and Empetrum nigrum) and herbaceous species (~35 %, Rubus idaeus and Chamerion angustifolium). This decline of the lichen barrens does not seem to be associated with recent climate change as it occurred mainly between 1967 and 1988, a period during which temperatures were relatively stable. Furthermore, the low lichen cover measured around sites disturbed by herring gulls indicates that the disturbances probably occurred after the lichen was replaced by vascular plants, which suggests that these disturbances were not responsible for the observed decline. However, herring gull disturbances seem to favour the development of an herbaceous cover. Besides the loss of lichen species, no negative effects of a vascular plant cover development was observed on the diversity, species richness nor abundance of functional groups. Our results do not allow us to identify the cause of the lichen narrends retreat. A change in soil condition caused by oraganic mater accumulation after the island emergence and permafrost degradation could be implicated, but still need to be investigate.
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Déterminants de l'hétérogénéité du recul de la lande à lichens dans la Réserve de Parc National de l'Archipel-de-MinganCaouette, Marianne 18 July 2018 (has links)
Tableau d'honneur de la Faculté des études supérieures et postdoctorales / Dans la Réserve de Parc National du Canada de l'Archipel-de-Mingan (RPNCAM), Québec, un important verdissement des landes à lichens est observé depuis 1967 et serait surtout lié à l’établissement d'espèces arbustives telles que la camarine noire (Empetrum nigrum L.) et le bouleau nain (Betula pumila L.). L’analyse de photos aériennes de l’archipel (1967, 1988 et 2009) suggère que le recul des landes à lichens serait hétérogène à l’échelle locale, certaines landes à lichens montrant un recul rapide et d'autres se maintenant dans le temps. L’objectif de notre étude était de déterminer quels sont les paramètres locaux (sols, exposition, etc.) favorisant le recul des landes à lichens à la RPNAM. Pour suivre l'évolution du recul, des cartes du couvert lichénique de sept îles de la RPNCAM ont été produites par classification supervisée par pixel à partir de photos aériennes. Les résultats démontrent un recul des landes à lichens de 71% entre 1967 et 2009, bien que majoritairement observé entre 1967 et 1988 (50%). À partir de modèles écologiques construits avec des caractéristiques locales, nous avons pu déterminer que l’épaisseur de la couche de sol organique est une variable d’importance pour expliquer le recul survenu (AICcWt = 0.44). Cependant, les facteurs locaux favorisant le recul ainsi que les patrons de colonisation par les plantes vasculaires diffèrent selon la période considérée (1967-1988 et 1988-2009). En effet, l’épaisseur de sol organique semble importante pour expliquer le recul observé durant la première période seulement, durant laquelle de grandes étendues de landes à lichens ont été colonisées par un front d’avancée d’espèces vasculaires. Cette étude nous permet donc d’enrichir notre compréhension des changements de communautés végétales en milieu nordique. / In the Mingan Archipelago National Park Reserve (MANPR) of Québec, Canada, an important greening has been observed at the expense of terricolous lichens since 1967. This phenomenon occurring in lichen heaths is most likely linked to the encroachment of shrubs like the black crowberry (Empetrum nigrum L.) and the dwarf birch (Betula pumila L.). Aerial photos of the Mingan archipelago acquired in 1967, 1988 and 2009 reveal a retreat that appears heterogeneous at a local scale, with some lichen heaths decreasing rapidly in extent and others appearing stable over time. Our aim was to determine which local-scale characteristics (substrate, aspect, etc.) promote the retreat of the lichen heaths on the islands. Using supervised classification on the aerial photos, vegetation maps of seven islands of the MANPR have been generated to track the plant communities’ changes and quantify the retreat in lichen cover. Maps results show an average decrease of 71% between 1967 and 2009, with the majority of the retreat observed between 1967 and 1988 (50%). Models built with local characteristics suggest that the soil organic layer (SOL) thickness is important to explain the retreat (AICcWt = 0.44). However, explanative factors and vascular plant colonization patterns differ depending on the time interval studied (1967-1988 and 1988-2009). In fact, SOL thickness seems only important to explain the lichen heath retreat observed during the first time period, during which extensive lichen heaths areas were colonized by an advancing front of vascular plants. This study extends our comprehension of northern ecosystems dynamics.
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L'addition de coquilles de pétoncles (Chlamys islandica) sur différents types de fonds marins : une alternative pour favoriser le recrutement des espèces commerciales?Guay, Martin 16 September 2021 (has links)
Nous avons évalué l'impact de l'ajout de coquilles vides de pétoncle sur des fonds marins sablonneux et rocailleux au nord du golfe du St-Laurent. L'impact a été plus important sur les fonds sablonneux, alors que la richesse en espèces a augmenté par un facteur de 3.7 et la diversité par 1.9. L'augmentation observée a été principalement le résultat d'une immigration plutôt que de la fixation de nouveaux individus. Les essais évaluant l'impact de différentes densités de coquilles sur des surfaces de 4 m2 ont démontré que la diversité en espèces a atteint un maximum à une densité de coquilles couvrant la moitié de la surface expérimentale. La richesse en espèces s'est accrue jusqu'à une densité de coquilles couvrant la presque totalité de la surface expérimentale. L'expérience sur l'effet de la taille des surfaces couvertes par des coquilles a démontré que la diversité en espèces avait déjà atteint un maximum à une surface de 1-m2, alors que la richesse en espèces atteignait un plateau à une surface de 4 m2. L'expérience démontre que l'addition de coquilles pourrait avoir un impact positif en augmentant l'abondance de nombreux invertébrés, incluant des espèces commerciales (pétoncles, buccins et oursins).
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