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The concept of sustainability transitions has become increasingly prominent in academic and policy discourses during recent decades, but the importance of the link between knowledge-producing epistemic practices and urban governance has been underappreciated in this discourse. Based on a case study of cycling in Copenhagen between 1900 and 2015, and drawing upon a governmentality-inspired analytical framework, this research demonstrates that transformative governance may be initiated by epistemic practices that render urban systems visible in other ways. Urban cycling has been reconstructed over time in Copenhagen as a traffic safety ‘problem’, a component of the experiential and liveable city, and a health-producing (and hence economically valuable) regional transport mode. The research findings emphasise that epistemic practices can provide a powerful stimulus for creating changes in urban governance. The results also provide support for initiatives to broaden the terms of academic debate on sustainability transitions.  相似文献   
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Cahill JF  Elle E  Smith GR  Shore BH 《Ecology》2008,89(7):1791-1801
Plants engage in diverse and intimate interactions with unrelated taxa. For example, aboveground floral visitors provide pollination services, while belowground arbuscular mycorrhizal fungi (AMF) enhance nutrient capture. Traditionally in ecology, these processes were studied in isolation, reinforcing the prevailing assumption that these above- and belowground processes were also functionally distinct. More recently, there has been a growing realization that the soil surface is not a barrier to many ecological interactions, particularly those involving plants (who live simultaneously above and below ground). Because of the potentially large impact that mycorrhizae and floral visitors can have on plant performance and community dynamics, we designed an experiment to test whether these multi-species mutualisms were interdependent under field conditions. Using benomyl, a widely used fungicide, we suppressed AMF in a native grassland, measuring plant, fungal, and floral-visitor responses after three years of fungal suppression. AMF suppression caused a shift in the community of floral visitors from large-bodied bees to small-bodied bees and flies, and reduced the total number of floral visits per flowering stem 67% across the 23 flowering species found in the plots. Fungal suppression has species-specific effects on floral visits for the six most common flowering plants in this experiment. Exploratory analyses suggest these results were due to changes in floral-visitor behavior due to altered patch-level floral display, rather than through direct effects of AMF suppression on floral morphology. Our findings indicate that AMF are an important, and overlooked, driver of floral-visitor community structure with the potential to affect pollination services. These results support the growing body of research indicating that interactions among ecological interactions can be of meaningful effect size under natural field conditions and may influence individual performance, population dynamics, and community structure.  相似文献   
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Research on the development of the interrelationship between society and environment is crucial for the understanding of contemporary landscapes. The West-Estonian archipelago provides an opportunity for such investigations because of its small size, landscape diversity, and well-defined economic activities. The contemporary landscapes of the islands reflect environmental changes resulting from centuries of human activity. This paper describes both natural and human factors in the change in landscape of small Estonian islands during the last centuries. During the period 1850–1940, human activity diversified the landscape structure. During World War II, with the establishment of Soviet rule, the islets were depopulated; their landscape became more uniform and lost their economic and ecological vitality. The re-establishment of private ownership of land and a market economy is predicted to result in positive changes in the landscape of the islets.  相似文献   
4.
Research on the development of the interrelationships between society and environment is crucial for the understanding of contemporary landscapes. The West-Estonian archipelago provides an opportunity for such investigations because of its small size, landscape diversity, and well-defined economic activities. The contemporary landscapes of the islands reflect environmental changes resulting from centuries of human activity. This paper describes both natural and human factors in the change in landscape of small Estonian islands during the last centuries. During the period 1850–1940, human activity diversified the landscape structure. During World War II, with the establishment of Soviet rule, the islets were depopulated; their landscape became more uniform and lost their economic and ecological vitality. The re-establishment of private ownership of land and a market economy is predicted to result in positive changes in the landscape of the islets.  相似文献   
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