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101.
The interactions of nature and society are intimately reflected in the degradation of the vast, yet diverse, landscapes and ecosystems of arid western China. The development of agriculture, especially irrigation, has altered rivers, soils and ecosystems so much that major ecological rehabilitation and restoration efforts have been needed since 1950. The catchments of the Tarim River in southern Xinjiang (the Tarim Basin) and of the Black River (Hei He) in Gansu Province and western Inner Mongolia provide examples of the benefits, difficulties and conflicts involved in dryland water management. In the early stages of the human development of these catchments, agriculture depending on irrigation using water from these inland rivers was encouraged. The over‐exploitation of these water resources led to such ecological problems as desiccation of lakes, drying out of rivers, degradation of soils and vegetation and lowering of groundwater levels, with consequent environmental and economic impacts. Since 1990 several high‐cost, national projects to re‐establish ecosystems have been initiated. Water is now released from dams in the headwaters of the rivers in order to restore water flows to the dried out lake basins. Such schemes have inevitably led to social problems and difficulties for the people who depended on the water from the dams for local irrigation. The contrasts in adjustments and attitudes over the use of water for agriculture and other economic activities, as opposed to schemes of restoration of ecosystems and ecological engineering, stem largely from two issues; inconsistent provision of information from the scientific community, and differing ideologies, namely environmental protection versus economic development.  相似文献   
102.
To evaluate the potential effects of population ageing on the outcomes of direct democracy, we analyze the effect of age on voting decisions in public referendums. In a case study of the Stuttgart 21 referendum on one of the largest infrastructure projects in Germany, we find that support for the project decreased significantly in age. A quantitative review of the relevant literature affirms that similar lifecycle patterns appear to be the norm in referendums on projects that require initial expenditures and pay off in the long run. Population ageing, thus, presents a potential threat to investment-like reform projects.  相似文献   
103.
This paper examines the political and corporate constructions of the 1995–96 drought crisis in West Yorkshire, when an unprecedented public furore was provoked by the threat of water-supply cut-offs. A key outcome of this process was a profound crisis of confidence over the governance of water resources, which can be linked to the privatization of the industry and, more broadly, to the processes of redrawing the boundaries of the state. The water industry illustrates the contestability of neoliberal reforms seeking to inspire market-led growth with minimal government intervention. In particular, political dogma about the anticipated benefits of market competitiveness failed adequately to take into account public concern for the 'common good'.  相似文献   
104.
While many urban policies and practices claim to offer an “alternative” to the “mainstream” of urban entrepreneurialism, they remain under-theorised and prone to alignment with entrepreneurial agendas. In this paper I examine fare-free public transport (FFPT) as a salient example of an alternative urban policy. Looking at Aubagne (France) and Tallinn (Estonia), I explore what happens when an alternative policy “comes to town”. I detect how FFPT enters local urban regimes, and study the (non-)participation of public transport passengers and workers in the decision-making process about whether and how to abolish public transport fares. My analysis reveals that albeit alternative policies such as FFPT seem to oppose entrepreneurialism, they may hinge on urban regimes that span across institutions, leave the local configurations of power unchallenged, and strenghten local elites. The adaptability of alternatives to diverse political and intellectual positions explains their resilience. Consequently, their radical character cannot be taken for granted and remains an object of political struggle.  相似文献   
105.
City officials are continuously working to attract airlines willing to fly to new destinations. The inherent expectation is that a more extensive aviation network stimulates economic growth. This paper investigates empirically the causal implication of this hypothesis. Using data on nonstop flights by origin and destination over the period 1984–2013, we propose a new measure for a metropolitan area's connectivity to the national aviation network. We then use this measure to investigate its contribution to local economic development, as captured by the growth in population, in total employment, in per-capita income, and new firm entry. To ensure causality, we use instrumental variable methods that exploit geography and destination airports growth as a way to capture the exogenous variation in the likelihood to add new travel routes. Our results suggest that a metropolitan area's air connectivity, resulting from an expansive local aviation network, has a positive effect on population, on employment and on the number of businesses established in that location.  相似文献   
106.
经济生产方式的变化在一定程度上折射出社会变迁的信息与轨迹。通过阐述一个客家村落——广西桂林毛村的水运经济的兴衰变迁,看到素以水运为命脉的毛村,一旦失去旧有的生产方式,他们的命运又将如何呢。  相似文献   
107.
珠江三角洲城际间运输联系的特征分析   总被引:27,自引:2,他引:25  
本文分析了珠江三角洲各主要城市之间客、货流量的空间分布形态,就珠江三角洲的整体交通运输形势而言,占第一位的是广州-东莞-深圳-香港一线。由于其优越的地理位置、悠久历史、社会经济持续高速的发展、最初改革开放的优惠政策、以及由此所形成的目前较为完善的政策体系,使穗港沿线成为珠江三角洲成型的交通运输走廊。同时珠江三角洲地区的空间运输联系具有强烈的广州指向性,目前尚未形成走廊的网络模式,对整体珠三角的发展并非十分有利。  相似文献   
108.
Wells located in the Colombian Andean foreland often produce biodegraded hydrocarbons and relatively fresh water (total dissolved solids concentrations of 2000 mg l?1 dominate across most of the basin). The ratio of water to hydrocarbon in the produced fluids is high and has often been interpreted by explorationists and simulation engineers as being due to massive meteoric water invasion. To challenge this hypothesis, previously published and existing data are compiled here, along with 68 new water samples collected from both the surface (rivers) and subsurface (production wells), which are analyzed for major elements, salinity, and stable isotope compositions. The data indicate a mixed origin for the water, which involves formation water, meteoric water, and a third source that we interpret as being related to diagenetic processes (such as clay dehydration). Analyses of the variation of the parameters from north to south and west to east allow us to define the mixtures as coming from waters of different origins and make it possible to determine the relative contribution of each source.  相似文献   
109.
Geomorphology in Canada, as elsewhere, has evolved into an essentially bipartite discipline focusing either on ‘process’ or broader ‘historical’ (Quaternary) landscape interpretation. A growing emphasis on process‐oriented research that relies increasingly on instrumentation and computational technologies has occurred. Critics of such research note limited applicability for landscape evolution, fashionability of methods and limited societal relevance. Indeed, some say we are not seeing the landscape for the processes. This article discusses the changing nature of geomorphology since the Quantitative Revolution of the 1950s including new advances, recent trends and challenges. Publication trends and recent advances suggest that the discipline is very healthy (following a slump in the early 1990s) and continues to evolve, which may reflect increasing research infrastructure and/or funding opportunities and new publications spotlighting Canadian research. Unfortunately, fundamental (less applied) research is threatened by funding program shifts, changing institutional pressures and a decline in research capacity from retirement attrition, and student recruitment challenges. Three research priorities are recommended: (1) continued fundamental research, (2) more integrated modelling to link micro scale processes to macro scale landform behaviour and (3) improvements in profiling our discipline amongst students and related professionals.  相似文献   
110.
Most livelihood research focuses on micro-level decisions affecting occupations but fails to examine wider scale processes that shape markets, institutions, and thus livelihood choices. A political ecology framework can help address this gap by providing ways to analyse how multi-scalar and extra-local practices, policies, and discourses affect local-level socio-environmental outcomes. In the qualitative research reported here, that framework is applied to Tha Kam, a peri-urban coastal sub-district of Bangkok, where most residents are small-scale aquaculture farmers. These farmers have experienced precipitous drops in incomes because of two major environmental changes: coastal erosion and wastewater intrusion. The causes are multiple and complex, and many originate not from practices within Tha Kham but from challenges present at a larger scale or that start upstream. The political and economic drivers of these problems stem from Thailand’s fragmented vertical and horizontal governance structure, unequal class relations in which smallholder farmers and peri-urban residents are marginalised, and lack of accountability and representation. This combination of multi-scalar factors and power imbalances has contributed to evolving injustices of peri-urbanisation, all of which are profoundly geographical in their significance.  相似文献   
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