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In 1987, the authors of Our common future argued that unless the world embraced and operationalized sustainable development, it would risk being overwhelmed by a series of interlocking crises related to population growth, urbanization, poverty and environmental degradation. Since then, many authors have argued that the world is on a worst case scenario trajectory. Post‐Rio assessments of progress towards sustainable development have been largely negative. Since 1987, climate change has added a new stressor to the mix while shortening the time frame for transformation. In the context of accelerating change and converging stresses is the concept of sustainable development as compelling today as it was twenty years ago? Is it reasonable to believe there are means by which to reduce poverty and simultaneously protect the environment? This article briefly reviews the global challenges that first stimulated the concept of sustainable development and asks how contemporary processes of global change are affecting both these challenges and this approach to addressing them. While there are some grounds for optimism, several variables are identified that make sustainable development increasingly difficult to design and implement. The article concludes with an evaluation of how these difficulties might be overcome, and why it is essential that we try. 相似文献
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ABSTRACT We use disaggregated data on Chilean plants, and the Chilean input–output table to examine the impact of agglomeration spillovers on total factor productivity (TFP). In common with previous studies, we find evidence for intraindustry spillovers, but none for general cross‐industry spillovers. This picture changes when we take vertical industry relations into account. There are important productivity spillovers from plants in upstream industries. Interestingly, a similar effect cannot be found from plants in downstream industries. The number of plants in these sectors has no effect on plant‐level TFP, just as the number of plants in other industries that are neither important upstream suppliers nor downstream customers also has no effect. 相似文献
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A. Stewart Fotheringham 《Geographical analysis》2009,41(4):398-403
This article examines the relationship between spatial dependency and spatial heterogeneity, two properties unique to spatial data. The property of spatial dependence has led to a large body of research into spatial autocorrelation and also, largely independently, into geostatistics. The property of spatial heterogeneity has led to a growing awareness of the limitation of global statistics and the value of local statistics and local statistical models. The article concludes with a discussion of how the two properties can be accommodated within the same modelling framework. 相似文献
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Tor A. Benjaminsen Faustin P. Maganga Jumanne Moshi Abdallah 《Development and change》2009,40(3):423-445
Farmer–herder conflicts in Africa are often presented as being driven by ‘environmental scarcity’. Political ecologists, however, argue that these conflicts should be analysed within a broader historical and policy context. This article presents a case study of a local conflict in the Kilosa District in Tanzania that tragically culminated in the killing of thirty‐eight farmers on 8 December 2000. To understand the conflict, the authors argue that it is necessary to study the history of villagization and land use in the District, as well as national land tenure and pastoral policies. Attempts at agricultural modernization have fostered an anti‐pastoral environment in Tanzania. The government aim is to confine livestock keeping to ‘pastoral villages’, but these villages lack sufficient pastures and water supplies, leading herders to search for such resources elsewhere. Pastoral access to wetlands is decreasing due to expansion of cultivated areas and the promotion of agriculture. The main tool that pastoralists still possess to counteract this trend is their ability to bribe officials. But corruption further undermines people's trust in authorities and in the willingness of these authorities to prevent conflicts. This leads actors to try to solve problems through other means, notably violence. 相似文献
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