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231.
A response to a recent paper by Barnes, arguing that the origins of geography’s quantitative revolution were not as monofocused as he suggests.  相似文献   
232.
We have analysed three recent earthquake sequences in the northern part of the Taupo Volcanic Zone. A 1998 sequence at Haroharo with a largest event of ML 4.8, and a 2004 sequence near Lake Rotoehu (largest event ML 5.4), had normal b-values, and displayed an aftershock decay pattern, with most of the activity within the first few days. In contrast, a 2005 sequence a few tens of kilometres away at Matata (largest event ML 4.1), had very different characteristics, with a slow development and decay, no tendency for enhanced seismicity after the larger events, and a very high b-value.The focal mechanisms of the Rotoehu and Matata events are normal, and have stress patterns consistent with the geodetically observed extension of the Taupo Volcanic Zone in a northwest–southeast direction. The extensive recent volcanism in the Okataina Volcanic Centre does not seem to have affected the stress pattern in this area.The Rotoehu sequence showed a strong resemblance, particularly in the time distribution of events, to the well-known swarm activity in the Vogtland region on the German/Czech border, in which larger events were followed by a burst of seismicity, as in a normal aftershock sequence. Some of the arguments that have been advanced to explain the Vogtland swarm as seismicity induced by fluid injection apply to Rotoehu, but there is no direct evidence of fluid involvement. The Matata sequence appears to have a continuing trigger mechanism, either a slow injection of fluid, or a slow slip event, in an environment in which opening pore spaces prevent high overpressures developing. The Matata sequence occurred close to the area of the 1987 ML 6.3 Edgecumbe Earthquake, so exhibiting two extremes of seismic temporal pattern, namely mainshock–aftershock and a swarm with many events of similar magnitude, within a small area.  相似文献   
233.
Tony Waltham 《Geology Today》2010,26(4):152-158
Gigantic floods that, for just a few days, had flow rates many times greater than the combined flows of all the other rivers of the world put together. Sounds ridiculous, and it's almost inconceivable, but it's real, and it all happened at the end of the last Ice Age. The water came from Lake Missoula, which exists no more, but the effects are still to be seen in the landscapes, most notably in the vast scablands of eastern Washington.  相似文献   
234.
With the resurgence of regions as key nodes in the global economy, there is a growing interest in better defining their competitive advantages, particularly those accrued through infrastructure provision. Two important components of this competitive landscape are information and communication technologies (ICTs) and commercial air passenger service. While the development of these two networks is frequently cited as being a critical factor in regional economic competitiveness, few empirical studies address the statistical relationship(s) between these infrastructures or the complexities associated with their spatial distribution. The purpose of this paper is to determine if an association exists between the provision of broadband telecommunication service and air passenger service in the United States. In addition, basic spatial statistical approaches are utilized to identify a suite of important social and economic determinants that play a central role in spurring infrastructure provision.  相似文献   
235.
Univariate indicators such as employment are often used to benchmark economic growth at the local and regional levels. However, the tremendous technological and industrial changes in the U.S. economy in the second half of the twentieth century suggest this practice may be outdated. In fact, the singular use of univariate indicators to benchmark regional development may obscure a much richer and more complex web of economic processes. Given the potential complexities associated with regional benchmarking in the current global economy, this paper will explore the numerical differences in economic performance presented by popular univariate indicators of regional growth. Results demonstrate a univariate approach to benchmarking presents an incomplete snapshot of regional performance that is incapable of capturing the multifaceted nature of economic growth in today’s global knowledge economy. Although job creation remains an important component to development efforts, many other factors should be considered in evaluations of regional performance, including the industries in which jobs are created and their associated wages.  相似文献   
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We have been living through several decades of great and rapid changes in the human condition. Life expectancies increased markedly during the twentieth century; populations are becoming 'older'; disease profiles are changing. The world is connecting up economically and electronically, market forces have become increasingly dominant, the post-Cold War political landscape has been transformed, cities are expanding rapidly, and material wealth is accruing — albeit unevenly. Meanwhile, however, a range of large-scale environmental changes is occurring, of which the most apparent is global climate change. This reflects a more fundamental process: the biosphere and its life-support systems are straining under the weight of human numbers, intensified food production, escalating carbon-based energy use and the spread of mass consumption behaviours. This revised version was published online in September 2006 with corrections to the Cover Date.  相似文献   
239.
Tourism as a local development strategy in South Africa   总被引:1,自引:0,他引:1  
The promotion of tourism has been identified as a key strategy that can lead to economic upliftment, community development and poverty relief in the developing world. In the last few years, tourism has also emerged as a significant development option in post–apartheid South Africa. In the context of some current debates on tourism in poor countries, the paper examines how economic, social and environmental resources are being utilized to promote tourism as a local economic development strategy in South Africa, and more specifically it focuses on current local government endeavours in this regard and two communities that have suffered the loss of their economic resource base. Tourism–based development initiatives, one in KwaZulu–Natal and one in the Western Cape, are evaluated in the context of generating economic growth, alleviating poverty and addressing the apartheid legacy of discrimination and inequality. The significance of the dynamics of development processes involved in these initiatives has much wider relevance for local economic development, both within South Africa and elsewhere.  相似文献   
240.
Climate change and sustainable development: towards dialogue   总被引:2,自引:0,他引:2  
The consequences of climate change and sustainable development remaining as separate discourses are explored, both in general and in the Canadian context. One of these consequences is the difference in emission and economic development scenarios generated by the two groups. A second is that strategies to reduce greenhouse gas emissions are designed and assessed in a narrow technical context, divorced from the economic and social forces that underlie them. We identify the need for climate change and sustainable development to be represented in a more explicit manner in each other's research agendas, and for integrated assessment of climate change to incorporate alternative methodologies that complement global scale integrated assessment models. These methodologies should include greater involvement of stakeholders as partners with researchers in a shared learning experience.  相似文献   
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