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1.
There is a large sociological literature on racial- class-, and economically- based segregation in the United States and there is some evidence that residential segregation by income may have deleterious health consequences for residents of large U.S. cities. The health consequences of segregation in Canadian metropolitan areas, however, remain unknown and the comparison with the U.S. is always compelling. In this paper, we investigate the hypothesis that residential segregation by income may be associated with mortality in Canadian and U.S. metropolitan areas. Given the strong relationship between individual level socioeconomic status and health, it follows that metropolitan areas which isolate individuals economically could produce conditions that severely limit the life chances and therefore the health chances of the most vulnerable. To investigate the association between residential segregation by income and population health, we examined the relationship between working-age mortality and Jargowsky's (1996) neighbourhood sorting index (NSI) for a large group of North American metropolitan areas. We found a relationship between increased segregation and increased mortality for U.S. metropolitan areas but no such relationship for Canadian metropolitan areas. We also determined that income segregation could not be considered in isolation from income inequality – that, in effect, income inequality provides the propensity for meaningful segregation to occur. We further demonstrated the importance of considering both income inequality and income segregation together, especially when the analysis is intended to compare metropolitan areas. We conclude with a discussion of the need for an improved measure of segregation to better reflect the theoretical arguments for the relationship between concentration of poverty and affluence and population health.  相似文献   

2.
Across the rural American West, the restructuring of rural capitalism has transformed production landscapes into those increasingly structured by the development and consumption of natural and cultural amenities. This project used principles from symbolic interactionism, ethnographic methods, and the analytical framework of regional political ecology to understand the role of environmental learning in negotiating the new management regime associated with amenity-based capitalism in rural Fremont County, Colorado. The study found that most amenity residents participate regularly in social learning about the environment through a variety of interpersonal and organizational behaviors. In addition, they are responding collectively to environmental risks and opportunities associated with wildfire, noxious weeds and invasive grass species, prospective uranium mining, and restoration of cultural-landscape features. Ultimately, the practices of environmental learning concern how private properties and assets will be managed relative to the social construction of the environment as an amenity for personal consumption. Conservation and management prospects in this and other rural areas in the postindustrial world can be enhanced by understanding the microsociology of exurban geographies and by engaging the social forms and processes related to this distinctive landscape construction.  相似文献   

3.
宫进忠 《地球科学进展》2012,27(10):1153-1160
在地球演化历史上,第四纪是人类诞生、发展和壮大的时代,它所形成的地质产物中记录了丰富的生态环境信息。河北省境内第四纪岩石地层(泥河湾组、赤城组、马兰组、迁安组)的风化指数CIA,Fe2O3/FeO,Fe/Mn等地球化学参数可作为年均气温、年均降雨量等气候因子的近似代用指标;华北地区人类文化遗址所在地水系沉积物中Hg,Sn和Au等元素含量随人类文明的演进而阶段性增高。这一结果表明,人类为了适应不断变化的自然地理环境(寒冷、干旱),不得不进行技术创新,从而产生了农业耕作、工业革命及现代信息产业等文明进步成果,但与此同时,却也导致了地质环境的人为污染,甚至可能引发全球温室效应。  相似文献   

4.
Based on a compilation of more than 100 kimberlite age determinations, four broad kimberlite emplacement patterns can be recognized in North America: (1) a northeast Eocambrian/Cambrian Labrador Sea province (Labrador, Québec), (2) an eastern Jurassic province (Ontario, Québec, New York, Pennsylvania), (3) a Cretaceous central corridor (Nunavut, Saskatchewan, central USA), and (4) a western mixed (Cambrian-Eocene) Type 3 kimberlite province (Alberta, Nunavut, Northwest Territories, Colorado/Wyoming). Ten new U–Pb perovskite/mantle zircon and Rb–Sr phlogopite age determinations are reported here for kimberlites from the Slave and Wyoming cratons of western North America. Within the Type 3 Slave craton, at least four kimberlite age domains exist: I-a southwestern Siluro-Ordovician domain (450 Ma), II-a SE Cambrian domain (540 Ma), III-a central Tertiary/Cretaceous domain (48–74 Ma) and IV-a northern mixed domain consisting of Jurassic and Permian kimberlite fields. New U–Pb perovskite results for the 614.5±2.1 Ma Chicken Park and 408.4±2.6 Ma Iron Mountain kimberlites in the State Line field in Colorado and Wyoming confirm the existence of at least two periods of pre-Mesozoic kimberlite magmatism in the Wyoming craton.

A compilation of robust kimberlite emplacement ages from North America, southern Africa and Russia indicates that a high proportion of known kimberlites are Cenozoic/Mesozoic. We conclude that a majority of these kimberlites were generated during enhanced mantle plume activity associated with the rifting and eventual breakup of the supercontinent Gondwanaland. Within this prolific period of kimberlite activity, there is a good correlation between North America and Yakutia for three distinct short-duration (10 my) periods of kimberlite magmatism at 48–60, 95–105 and 150–160 Ma. In contrast, Cenozoic/Mesozoic kimberlite magmatism in southern Africa is dominated by a continuum of activity between 70–95 and 105–120 Ma with additional less-prolific periods of magmatism in the Eocene (50–53 Ma), Jurassic (150–190) and Triassic (235 Ma). Several discrete episodes of pre-Mesozoic kimberlite magmatism variably occur in North America, southern Africa and Yakutia at 590–615, 520–540, 435–450, 400–410 and 345–360 Ma. One of the surprises in the timing of kimberlite magmatism worldwide is the common absence of activity between about 250 and 360 Ma; this period is even longer in southern Africa. This >110 my period of quiescence in kimberlite magmatism is likely linked to relative crustal and mantle stability during the lifetime of the supercontinent Gondwanaland.

Economic diamond deposits in kimberlite occur throughout the Phanerozoic from the Cambrian (Venetia, South Africa; Snap Lake and Kennady Lake, Canada) to the Tertiary (Mwadui, Tanzania; Ekati and Diavik in Lac de Gras, Canada). There are clearly some discrete periods when economic kimberlite-hosted diamond deposits formed globally. In contrast, the Devonian event, which is such an important source of diamonds in Yakutia, is notably absent in the kimberlite record from both southern Africa and North America.  相似文献   


5.
Mutual climatic range (MCR) analysis was applied to 15 North American beetle assemblages spanning the interval from > 52 000 to 17 200 yr BP, bracketing a Mid-Wisconsin interstadial interval. The analyses yielded estimates of mean July (TMAX) and mean January (TMIN) temperatures. The oldest assemblage (> 52 ka) yielded TMAX values 7.5–8°C lower than present and TMIN values 15–18°C lower than present. A Mid-Wisconsin interstadial warming dating from 43.5–39 ka was rapid and intense. At the peak of the warming event, about 42 ka, TMAX values were only 1–2°C lower than modern. This level of amelioration apparently lasted only about 2000–3000 yr. By 23.7 ka, TMAX values declined to 11.5–10°C lower than modern, but another, small-scale amelioration is indicated by assemblages dating from 20.5 to 19.7 ka. The interstadial event recorded from the site at Titusville, Pennsylvania closely matches the timing and intensity of the climate change estimated from British beetle faunas in the Upton Warren interstadial. Another warm interval (ca. 31–32.5 ka) has been documented from fossil beetle assemblages in Europe and North America. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   

6.
Soyeun Kim 《Geoforum》2010,41(4):627-637
This article aims to illustrate the extent and ways in which a traditional development aid project became the focus of a ‘greening’ process in the 1990s (and beyond). The article examines the San Roque Multi-purpose Project in the Philippines - a major Japanese bilateral international cooperation project - from a political ecology perspective. The analysis highlights how a complex story of contemporary aid dynamics in the bilateral Japan-Philippines relationship influenced this ‘greening’ process. The article interrogates critically and empirically the stated greening of a proto-type development aid project. This specific example of the practices of the Japanese aid industry is set within the context of the wider political economy of both donor and recipient elite interests.  相似文献   

7.
In this study a 2D basin model has been built along a transect crossing the Horn Graben in WNW-ESE direction. The aim of the investigation was to improve the understanding of the thermal evolution of the basin and its influence on possible petroleum systems. The 2D model of the subsurface is based on one seismic line and data from two exploration wells. Both wells TD’ed in Triassic sediments. The updoming of the Ringkøbing-Fyn High began during Late Carboniferous–Early Permian. At the end of the Permian the Horn Graben became active due to regional extension. The subsequent sedimentation history from Triassic to date is well recorded by well reports. A matter of debate has been whether or not significant amounts of Pre-Permian sediments exist in this area of the North Sea. Since organic material rich Paleozoic sediments serve as source rocks in widespread areas of North Germany and the southern North Sea it would be of great importance to know whether the same deposits exist in the Horn Graben. Nielsen et al. (Bull Geol Soc Denmark Copenhagen 45:1–10, 1998) introduced a model, which shows Paleozoic sediments covering the basement at a maximum depth of 6.5 km. Assuming, Paleozoic sediments are underlying the Permian salt deposits there should be an active petroleum system present. The 2D model includes the Paleozoic source rock and tries to explain why two exploration wells have not found petroleum.  相似文献   

8.
Scale, as concept, has featured prominently in political ecology and remains, even if implicitly, a crucial point of analytical reference. Recent studies, drawing from both human geography and ecology, have sought to demonstrate how scales, rather than pre-existing ontologically, are both socially and environmentally produced. Given the different scales through which social and environmental processes occur, the study of society-environment relations can be improved by analysing varying scalar configurations of interaction. This recent and promising methodological corrective would greatly benefit from a dialogue with world-systems approaches, which integrate diverse scale-producing processes and to some extent overlap in scope with political ecology. World-systems perspectives, by focusing on the long-term systemic character of people-environment relations, effectively connect micro- to macro-scale social and ecological processes and explain long-term internal dynamics and interrelations of systems at different scales. Conversely, world-systems approaches could learn much from political ecologists’ consideration of nonhuman processes into understandings of scale and society-environment relations, which has a long tradition in geography, as well as from the more context-sensitive analytical framework brought to those understandings. Case studies are discussed to demonstrate not only how these two perspectives could be integrated, but also how explanations of environmental change can be thereby improved. Combining the two approaches provides the basis for a more ecologically oriented world-systems paradigm and, in political ecology, for greater sensitivity to socially large-scale systemic processes and, given the originally anti-capitalist underpinnings of both paradigms, for more political coherence.  相似文献   

9.
The world is facing a severe water crisis. According to the UN, by 2025 50% of the world’s population will face water scarcity. In India, where 70% of irrigation and 80% of domestic needs are met with groundwater, demand for this resource is expected to exceed supply by 2020. This has led to recent calls for groundwater governance reforms within India, and specifically within the state of Rajasthan, where no regulation exists today. The success of these reforms hinges on the interaction of the state and its agents with local users and managers of groundwater resources. Underpinning these encounters, though, are tensions between local and state forms of groundwater knowledges. The question analyzed here is in what ways do conflicting environmental knowledges adversely affect the management of overexploited groundwater resources in water-scarce India? To address this question, I examine the coevolution of pre-colonial, colonial, and post-independence groundwater and irrigation knowledges and technologies in Rajasthan, India to expose the ways that they are produced, contested, legitimated, and hybridized. The paper argues the following three claims. First, the relationship between the state and local producers of groundwater knowledge practices is non-linear and porous. For instance, the way that state subjects experience the state is uneven because within and in-between historical moments the state may attempt to assimilate, reorganize, plagiarize, or disparage local knowledge. Second, these attempts produce or exacerbate existing historically rooted tensions between farmers and state groundwater engineers. But in response, farmers often seek out non-state avenues of expertise, such as tubewell drilling firms. This results in the further hybridization of knowledge practices and also in the present-day marginalization of the state. Third, the relationship between farmers and the state is further strained because of a current lack of state visibility in the study area and also because the state continues to “see like a state”. These shifting meanings and power relations around groundwater and irrigation knowledges produce tensions that will undoubtedly negatively impact future groundwater governance strategies.  相似文献   

10.
Bolivia’s leftward political shift, which is frequently described as “post-neoliberal,” is crucially linked to the ideal of autonomy. While autonomy has a long history among leftist theorists and social movements in Latin America, its contemporary importance is related to an ongoing effort on the part of scholars and activists to identify an alternative organizational form that eschews both state actors and private entities. Drawing on fieldwork conducted with a group of community-run water systems in peri-urban Cochabamba, this paper asks what autonomous water governance looks like in practice. By presenting a case in which the community water systems made a series of structurally limited “autonomous” decisions that ultimately bound them more closely to the local state and private sector, the paper argues that autonomy faces socio-ecological limitations when conceptualized as a project of internal self-governance. Socio-ecological processes take place at multiple scales and over long time spans; a radical politics of autonomy therefore necessitates a spatially extroverted project that focuses on building strategic alliances that strengthen community autonomy in the long-term.  相似文献   

11.
Petra Tschakert  Kamini Singha   《Geoforum》2007,38(6):1304-1321
This article provides a counter-narrative to the dominant discourse of marginalization and criminalization of Ghana’s illegal gold miners (galamsey) by focusing on the contested mercury debate. We first examine the complex and multifaceted policy problem that underlies the current conflictual aspects in the small-scale mining sector, arguing that mercury use and contamination are key elements in the antigalamsey rhetoric. Second, we describe an interdisciplinary pilot study on human and environmental health that involved health personnel and illegal miners from two sites. Through participatory ranking and mapping activities, we explored participants’ understanding of mercury and other life hazards as well as causes and consequences of mercury contamination. We used chemical indicator strips to sample contaminated areas in collaboration with the miners. By drawing upon novel concepts from the environmental justice and ecohealth literature, we propose a political ecology of human and environmental health that advocates recognition of galamsey operators and their participation in learning opportunities as a first step out of the current impasse in the Ghanaian small-scale mining sector.  相似文献   

12.
Diana K. Davis 《Geoforum》2005,36(4):509-524
In Morocco the crisis narrative of desertification has been invoked for decades to facilitate and justify policy and legal changes that have systematically disadvantaged pastoralists and damaged the environment. The existing data from southern Morocco, however, do not support the claims of widespread desertification due to overgrazing or other pastoral activities. Furthermore, many anti-desertification and range improvement projects in southern Morocco have not succeeded. In an effort to rethink desertification and range ecology in Morocco, this paper presents an overview of the indigenous knowledge of range ecology among the Aarib, a group of camel pastoralists in southern Morocco, and compares it to the “expert” knowledge of Moroccan range managers. It suggests that this expert knowledge is based on questionable evidence and that it has been privileged over local knowledge primarily for political, economic and administrative reasons. The discrepancies between expert and indigenous knowledges of range ecology presented here underscore the need to reconsider range ecology in Morocco, taking indigenous ecological knowledge into account. Doing so may point the way to more successful development and conservation projects which are more environmentally appropriate and socially just. Not doing so will likely exacerbate environmental degradation in the region.  相似文献   

13.
John Holmes 《Geoforum》2004,35(1):9-21
Historically, political struggles to define the geographical scale at which labour relations and collective bargaining will be conducted have been of crucial significance to the labour movement. Today, workers and their unions face very difficult challenges. In many manufacturing industries changes in the organizational structure of production at different geographical scales have undermined the effectiveness of the organizing and collective bargaining strategies associated with traditional industrial unionism. This paper focuses on collective bargaining strategies developed by North American autoworkers’ unions to respond to the extensive restructuring of the automotive industry that took place during the 1990s. These strategies include innovations in the structure and content of collective bargaining and efforts to redefine the scale at which collective bargaining takes place. Following a brief discussion of the challenge posed by the integration of Mexico into a continent-wide production system, the analysis focuses on the strategies devised by the Canadian Auto Workers (CAW) union during the 1996 and 1999 rounds of collective bargaining to address issues raised by outsourcing and modular manufacturing. With outsourcing, the automakers are not so much eliminating jobs as they are deciding who gets to do them, at what price, and under what working conditions. With modular manufacturing, the organizational boundaries between firms are blurring and the terms and conditions of work in one firm arguably are becoming dependent upon management decisions made in another firm. The CAW’s response has been to develop new collective bargaining strategies including the concepts of ‘work ownership’ and ‘satellite bargaining’ which involves redefining the traditional geographical extent of the bargaining unit. While the empirical focus is on the North American automobile industry, the general issues related to the re-scaling of production, and especially outsourcing and modular manufacturing, are common across a range of manufacturing industries.  相似文献   

14.
15.
Academics across disciplines are increasingly employing political ecology lenses to unpack conflicts related to resource extraction. Yet, an area that remains under-researched and under-theorised is how environmental impact assessments (EIAs) are embedded in politics and imagined as sites of power relations. Drawing on long-term fieldwork in Zimbabwe engaging small-scale gold miners, EIA consultants and government officials, this article examines the changing social significance of EIAs during and after a nationwide police operation that was framed by authorities as targeting non-compliance with environmental policy, illegal mining and illicit trading. Among other articulations of dissent, small-scale miners associations protested that EIA enforcement rhetoric served unjustly as a rationale for halting livelihoods and extracting rent from miners in times of economic difficulty. The article challenges EIA narratives that focus narrowly on risk management or governance failure, exploring technocratic obfuscations and how enforcement rhetoric was perceived in relation to criminalisation and coercion, expert environmental consultancy cultures and adapted legacies of colonial practice in contemporary dynamics of rule. Heavy-handed policing under the banner of enforcing order impinged on livelihoods and had counterproductive effects in addressing environmental problems, while complying with expensive EIA report-producing requirements was far beyond the means of most small-scale miners. The article rethinks how technical EIA rhetoric becomes entangled in spaces of contentious politics, the perils of looking only at particular scales of relations to the exclusion of others, and what it means to re-engage Donald Moore’s notion of “shifting alignments and contingent constellations of power.” Suggesting future directions in political ecology theorising in relation to extractive sectors, it calls for careful attention to the situated politics of EIAs – situated in time and space, amid varying relations of power – and how multiple hegemonic practices are conceptualised and challenged.  相似文献   

16.
Water flows through time are connected to specific instances of socionatural and sociotechnical assemblages of human and non-human components. We propose the concept of “water palimpsest” in order to characterize the complex histories of chemical and metabolic alterations embodied in water flows, potentially disruptive for humans and other living beings. Through the concept of palimpsest we interpret the configuration of water flows as constantly evolving towards new patterns maintaining at the same time traces of past mixtures. In order to decipher water pollution by means of a political ecology approach we argue that it is necessary to characterize the historical contours under which certain substances in river waters appear, interact and become hazardous. Engaging critically with literature on assemblages but also with chemical and epidemiological scientific literature, and drawing from archival and oral sources, we provide an account of historically produced pollution in the waters of Llobregat River (Catalonia) by unravelling the assemblages that shape the water palimpsest in this river. In parallel, we narrate the advances in instrumentation and analysis which permitted to detect and measure substances beyond recognition by human senses and preceded legal regulations on pollutants, starting from milligrams and (thus far) arriving at nanoscales. Focusing on the emergence of three typologies of pollutants – salts, trihalomethanes (THMs) and endocrine disruptors (EDs) – we unveil how these three assemblages embody specific instances of Llobregat socioenvironmental history, pointing towards a palimpsest characterized by increasing levels of complexity and uncertainty. The concept of water palimpsest allows us to incorporate non-human agency into the analysis of water quality and to infuse political ecology with materiality and thus with a (largely missing) focus on physicochemical and biological processes.  相似文献   

17.
Carbon markets have gained traction worldwide as an ostensibly win–win solution to climate change, providing low-cost emission reductions in the Global North and sustainable development in the Global South. However, sustainable development and livelihood co-benefits have largely failed to materialize in a range of carbon offset projects, particularly those in forest communities. While some scholars explain this failure as an outcome of fundamental tradeoffs between market efficiency and sustainable development, others argue that institutions of common property land tenure can resolve tradeoffs and generate important co-benefits for local communities. Using a political ecology approach, integrating insights of Karl Polanyi and Noel Castree on the commodification of nature and evidence from a carbon forestry project in Chiapas, Mexico, this article grapples with the ways in which carbon market requirements shape forest governance within common property tenure arrangements. I argue that the centralization of forest governance and decision making into the hands of project implementers and brokers, the necessity for legible land rights and boundaries, and the technical requirements for measurement, calculation, and monitoring of carbon have reshaped forest governance in ways that have undermined the social and ecological benefits often associated with common property management schemes. This research therefore demonstrates that so-called tradeoffs between market efficiency and equitable sustainable development goals may not be inherent to carbon forestry and calls into question the reliance on disembedding market mechanisms for climate change mitigation in forest ecosystems. As such, this work has important implications for REDD+.  相似文献   

18.
In this paper we outline the limitations of Environmental Justice theory when it comes to explaining and theorising the politics of contemporary environmental movements. Justice, we argue, needs to be understood not as a formalised and preconceived ‘thing’ to be delivered or applied but as an open egalitarian ideal that movements across the world continuously redefine in embodied and performed ways which are historically and geographically distinct. Drawing upon the fifteen year long anti-mining struggles of Rosia Montana, Romania, we explore the tension between seeking ‘traditional’ forms of justice (i.e. dialogic consensual politics) and putting forward more radical demands for socio-ecological change, in which representation and recognition are seen as insufficient practices for distributing justice. Visibility (rather than recognition) and egalitarian politics (rather than distribution) become the quilting points of struggles of many contemporary environmental movements, equality can only be enacted (or staged) through praxis that disrupts the distribution of the sensible experience and exposes the arbitrariness and incompleteness of power. We argue that in order to analyse and theorise the praxis of contemporary environmental movements, it is imperative for geographical literature to engage with post-foundational theory, and ‘un-do’ pre-conceived ideas and theorisations of (environmental) justice.  相似文献   

19.
张贵宾  张立飞  宁远煜  韩磊 《岩石学报》2014,30(10):2835-2842
本文运用LA-ICP-MS和SIMS对柴北缘超高压变质带中东端沙柳河剖面中的副片麻岩进行了锆石和金红石U-Pb年代和微量元素分析。锆石边部的变质时代为425±6Ma,所对应的锆石Ti含量温度计计算出的温度为689±14℃。金红石U-Pb定年给出的年龄为414.0±6.3Ma,代表了副片麻岩在折返过程中冷却到金红石U-Pb封闭温度约570℃的时代。而金红石Zr含量温度计给出同锆石边部较一致的温度685±9℃,代表了峰期变质时代的温度条件。根据锆石的变质时代和变质温度以及金红石的冷却年龄和封闭温度所限定的T-t轨迹,可以得出此副片麻岩在折返过程中的冷却速率约为11℃/Myr。  相似文献   

20.
Recent work on return migration in China suggests return migrants bring with them new knowledge, skills, and potentially beneficial relationships accumulated during their sojourns, enabling them to introduce new forms of leadership and community action. Social remittances of this kind could be read as carrying the potential to enhance collective action in support of sustainable local natural resource-based livelihoods. This study of the links between return migration, leadership and collective action in water management sounds a more cautionary note, demonstrating that home communities may respond to return migrants in ways that repeatedly mark and reiterate gender and kinship norms, reiterating gender, generational and clan-based social hierarchies. The paper draws on and contributes to recent feminist political ecology approaches to show how migrant returnees’ ’social remittances’ translate into leadership in collective action in a rural Chinese village in ways that reinforce existing gender hierarchies and social positions within the community, thus questioning the extent to which any influx of new ideas, relationships and practices acquired from migrant experiences necessarily destabilizes power and authority in the village in any meaningful way.  相似文献   

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