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The study demonstrates that the orbital climatic diagram (OCD) built on the basis of the simplified and general concepts of mechanisms for climatic response to orbital forcing can be a reasonable alternative to Milankovitch’s and his followers’ discrete insolation curves, which are widely used in paleoclimate interpretations. Comparison of the OCD and the oxygen isotope record LR04 indicates a fairly good match (considering the simplicity of the OCD construction and interpretation) in 0–1240 ka. The study discusses some discrepancies in the chronology and structure of the LR04 and OCD. It was shown that climate response may differ from that predicted by orbital insolation forcing on the basis of the generally accepted mechanisms causing transformation of orbital signals. It was shown that a shift from a dominant glacial periodicity of 41 to 100 k.y. (Middle Pleistocene transition) took place at ~1240 ka. Since then, the 100-k.y. eccentricity cycle has not been interrupted. Therefore, strictly speaking, the revised numbering of marine isotope stages (MIS) should be adopted for the interval of 1240-900 ka to reflect realistic 100-k.y. cycles instead of 41-k.y. cycles, similar to the interval of 900–100 ka.  相似文献   

4.
The paper is focused on recent displacement rates in the Altai-Sayan region, obtained by hydroleveling, leveling, and satellite geodesy. Effective elastic moduli and viscosity parameters of the crust are used in the modeling of coseismic and tectonic processes. The elastic moduli are determined from measurements of periodic vertical displacements during seasonal loadings of the Sayano-Shushenskaya hydropower plant. We present the results of the modeling of coseismic displacements during the earthquakes of 10 February 2011 (M = 6.1) and 27 December 2011 (M = 6.7) in Tuva and West Sayan. The results of GPS determinations for postseismic displacements in the Chuya earthquake zone (Gorny Altai, 27 September 2003, M = 7.5) are analyzed; models for the geologic medium are selected; and its effective viscosity is estimated. The tectonic component of the recent crustal displacements in the Altai-Sayan region is defined.  相似文献   

5.
People’s reasons for visiting national parks have been well researched. So too have their park activities and how diverse activities potentially affect visitors’ park experiences (e.g. perceptions of overcrowding). Far less research has examined how park users’ environmental values might affect their perceptions of other users and the appropriateness of different activities – a potential source of conflict. Relationships between personal environmental values and environmental and social perceptions are complex and interactive in the context of park visitation. Visitors’ encounters with other users can powerfully affect their experience and enjoyment of parks, in turn reflecting such factors as values-related expectations and judgments in the context of national parks. Personal and social values may also play an important role in influencing whether different activities are perceived as ‘out of place’ in the context of national park place meaning, yet the conceptualization of values within geographic literature on parks remains comparatively weak.This paper utilizes a definition of values, derived from a concise review of the geography and social psychology literatures, to explain the results of survey research we undertook within national parks in Queensland, Australia. We use a ‘values-behavior hierarchy’ conceptual framework to consider how the personal environmental values of a sample of park visitors (n = 404) potentially affected patterns of park visitation, user activities, and user conflicts. Findings suggest that visitors’ environmental values shaped how they perceived other park users and the appropriateness of their activities. This has international implications for geographic research and other disciplines and professions involved in national park visitation, park use, and human impacts, on and of these powerful places.  相似文献   

6.
This article examines young Peruvians’ aspirations and the role of migration in their imagined futures, from a generational perspective. The data come from Young Lives, a long-term study of childhood poverty combining survey and qualitative approaches with children and their parents. The paper uses a biographical approach that sees migration as part of individual biographies as well as social structures and life course processes. The aim is to deepen understanding of the social contexts in which aspirations for and by children are generated, paying close attention to family migration histories, dynamic household contexts, and children’s migration networks. The analysis focuses on the time-spaces of migration aspirations, showing the way past, present and future are interconnected. It also emplaces aspirations by focusing on the way aspirations by and for children are constituted in and through particular places. The conclusion reflects on the role of poverty and argues that ‘aspirations’ are about much more than abstract ‘futures’; they orient actions in the present and say a great deal about young people’s current realities and relationships.  相似文献   

7.
Because of the role that peripheral forest landscapes played in postwar nation-building, the Lao military has long played a significant, even if often hard-to-see, role in the administration of the country’s protected areas. This role is becoming increasingly apparent as transnational market-based forest governance efforts begin to threaten military administration of protected areas. As a consequence, the multi-dimensional nature of security – both defensive in the classic military sense, but also increasingly economic and complex – is coming to light through uses of what we describe as the security exception: the invocation of national security, in this case by military actors, to manage the reach and efficacy of emerging forest governance efforts. Projects to reduce climate-related emissions from deforestation and forest degradation (REDD+) have been especially prone to trigger the security exception due to their focus on forest measurement and change over time, and are examined here in two cases from protected areas in western and southern Laos. We suggest that even as conflicts over forest management may be interpreted through the lens of foreign domination and the loss of domestic sovereignty – indeed the security exception feeds on such interpretations – these conflicts are better understood as struggles within the Lao state and society over the how to manage and use forest resources in a context of economic uncertainty and persistent underdevelopment. In such a context, the role of conservation NGOs and Western donors as gatekeepers to ongoing transnational governance efforts is nonetheless highly significant.  相似文献   

8.
B.M. Taylor 《Geoforum》2012,43(3):507-517
Extensive rural regions are facing major socio-economic, political and environmental change from the dual effects of agricultural restructuring and environmental degradation. While central governments often rely on regional level policy responses, local actors, such as rural local governments may resist these ‘top-down’ initiatives. This paper examines the oppositional response of 34 rural local governments to state-led regionalisation for economic development and natural resource management in the extensive and sparely populated Wheatbelt region of Western Australia. The analysis explores how state threats of amalgamation; shifting national policy empathies in rural development; and, local preferences for horizontal rather than vertical forms of cooperation are influential in catalysing a brand of defensive regionalism amongst local government actors. Adopting this defensive posture allowed local actors to both buffer state intervention and improve the effectiveness of their own cooperative planning and management activities for sustainable development. These observations are interpreted through concepts of collective identity formation, providing an analytical perspective that is sensitive to the inter-scalar politics in rural governance.  相似文献   

9.
Brisbane is Australia’s third largest city, and capital of the state of Queensland. It has a sprawling urban footprint and impending connections to neighbouring metropolises, said to create a ‘200 km city’. The governing body of Brisbane controls the largest municipality in Australia, with unrivalled opportunity to influence both urban planning and marketing for the CBD and suburbs. Brisbane is home to over one million people, and its population has grown rapidly over the past decades, doubling in the past 40 years. Brisbane represents the quintessential city with an emerging quest for urbanity, both in brand and physical form. The relationships between the city’s urban planning and its branding is not well examined, despite clear entanglement between these two strategies. We use a case-study analysis of both Brisbane City (which is glossed as the Central Business District) and an outer-suburban area, Inala, to interrogate how urban identities and brand are being constructed in relation to their social settings and governance, with particular reference to the importance of city branding and its relationship to planning strategies. The manifestation of branding and relationship to place qualities at the core and on the periphery of Brisbane are examined, with relevance for other rapidly growing, ambitious cities. The focus of Brisbane’s push for urbanity is on the city centre, and is not representative of the typical suburban condition, nor of many cities dominated by suburban forms. An analysis of place brand, planning strategies and resident’s responses to place, from planning, architectural and anthropological perspectives are offered, as an alternative reading of place brand from the marketing dominated approach usually favoured in branding analysis. We make recommendations to incorporate a more complete version of place in the construction of a “genuine” urbanity. We argue that the recognition of resident-centred place identity in place branding will produce more socially sustainable places, as well as more authentic city brands.  相似文献   

10.
At scenic sites across China, rural officials compelled to maximize revenue use local state authority over protected areas to foster “tourism dynamos”. Local states set up infrastructure and institutions around rural attractions that channel the circulation of tourists, churning out revenues that meet quotas and fund further expansion of attractions and towns. To make these dynamos turn, local authorities have displaced resident-led tourism operations they had previously helped set up. Residents are reincorporated in varying ways and often retain land use rights. Meanwhile, as revenues stream out of attractions, what little is invested in environmental protection goes to maintaining scenery. Local governments also accomplish spatial transformations, within each park intensifying surplus generation in areas zoned for tourism while reserving other areas from use, and beyond park boundaries linking attractions together on tourism circuits radiating from central towns. This state-driven transformations depend on how the reservation of land from commodity exchange within protected areas comes together with specific state capacities to enable tourism intensification. These processes, which I label “developmental conservation,” call attention to selective commodifications and the mediating role of the state in protected area governance in China and beyond.  相似文献   

11.
It is shown that the parameters of the solar-wind magnetic field are determined by regions in coronal holes at distances of 1.1–1.4 solar radii, where the field lines are radial at low heights. Expanding further in a narrow nozzle or funnel, the field lines become radial throughout the unipolar region at 2.5 solar radii. Hence, the traditional approach of comparing the characteristics of the interplanetary field at the Earth’s orbit and at the corresponding helio-projection point on the Sun is not quite correct. It gives good results for the signs and sector structure of the field; however, the magnitude of the field is formed in a more extensive area. Taking this into account, we can correlate the field values on the Sun with the interplanetary magnetic field (IMF), and thus explain the absence of weak fields in the vicinity of the IMF neutral line (the two-peaked nature of the distribution).  相似文献   

12.
In recent years, there has been heightened interest in creating more environmentally sustainable forms of urban development in China. Central in these greening initiatives has been increased attention on promoting public participation in community-based environmental activities. Focusing on China’s green community initiatives, we examine the production and effects of participation in a state-led development program. Our analysis considers how incentives for program organizers and participants are structured by broader political and economic imperatives facing Chinese cities. We also consider what influence China’s history of neighborhood-based mobilization campaigns had on the meanings and methods of participation in green communities. To understand how urban development processes and memories of mobilization influence participation at the local level, we present two examples of the community greening process from the city of Guangzhou, comparing policy outcomes between a new and older neighborhood. This article seeks to demonstrate that the participatory processes associated with such an urban environmental initiative cannot be adequately understood without reference to earlier participatory practices and broader policy priorities guiding development in Chinese cities.  相似文献   

13.
Godwin Masuka 《Geoforum》2012,43(3):573-584
The paper examines the relations between farmers and The Cotton Company of Zimbabwe (COTTCO) in Rushinga district of Zimbabwe. Based on interviews with farmers and secondary data, it examines the practice of side marketing of contracted seed cotton. While a large body of literature has discussed the social and economic effects of contract farming on farmers, there are less critical studies on side marketing of crops by farmers in unstable economic and political environment such as Zimbabwe. The paper demonstrates that farmers taking advantage of the macroeconomic environment in Zimbabwe violated contracts by selling seed cotton to other buyers. In the process, farmers renegotiated the meaning of the contract and appealed to market rationality embedded in the neo-liberal ideology. For these farmers, side marketing was part of a survival strategy, albeit in imperfect markets and a difficult economic environment. Nonetheless, side marketing of seed cotton strained relations between farmers and COTTCO. The paper shows the tensions in contracts that require regulation by the state and the neo-liberal ideology that promote free markets and argue against strong regulation.  相似文献   

14.
In this paper, I advance debates that argue that we need to reconceptualise global work from a mobilities perspective by looking how the representation of movement connects with the experience of movement. By looking at the imaginative geographies of Singapore for the British corporate expatriate, I explore how the qualitative representation of place is changing within managerial discourses from a hardship to an opportunity. In doing so, the paper argues that we need to combine understandings of the global economic flows that move some transnational migrants with their everyday lived experiences in order to explore what qualitatively makes work global. This allows us to highlight the multiplicity of ways in which transnational migrants can be understood rather than trying to impose singularity.  相似文献   

15.
Chapman and Pollack (C and P)[2007, Int J Earth Sci] criticize Hamza et al. [2007, Int J Earth Sci] for using actual heat flux measurements in young oceanic crust instead of values from 1-D cooling models. The rationalization of C and P and previous authors is that hydrothermal circulation causes the discrepancy between model and measurement. However, the discrepancy between model values and measured heat flux exists over the entire ocean floor and is opposite to the perturbations that hydrothermal circulation would superimpose on a conductive system [Hofmeister and Criss (2005) Tectonophysics 409:199–203]. The error lies in force-fitting a 1-D cooling model to the 3-D oceanic crust [Hofmeister and Criss (2005) Tectonophysics 395:159–177]. Shortcomings of the 1-D model include mathematical errors, such as use of volumetric rather than linear thermal expansivity to describe contraction which, by assumption, is limited only to the Z -direction [Hofmeister and Criss (2006) Tectonophysics]. This 3× error, traceable to McKenzie and Sclater [1969, Bull Vocanol 33–1:101–118], accidentally provides good agreement of model values with globally averaged seafloor depths for young, but not old ages, and is the sole rationale for using the simplistic cooling model. There is no justification for selective substitution of erroneous 1-D model values for measurements only for the younger half of the 3-D oceanic crust, as stridently and arbitrarily promoted by C and P. Hamza et al. [2007, Int J Earth Sci], in contrast, use the scientific method, which calls for discarding models that do not well describe physical phenomena. The remainder of this report summarizes the shortcomings of cooling models, particularly the half-space cooling (HSC) model touted by C and P, and explains how hydrothermal circulation affects heat flux. We focus on the basics, as these have been misunderstood. With the key issues of C and P being erroneous, it is not necessary to address their remaining comments, many of which enumerate the vote for an imagined, gargantuan circulation of hot fluid through oceanic basins that is somehow warmed without removing heat from the rocks. The use of “consensus” to belittle valid challenge is the enemy of the scientific method.  相似文献   

16.
This article examines changing water governance modalities in the context of the neoliberalization of nature. Specifically, it focuses on Brazilian water sector reforms passed in 1997 that mandate decentralized and participatory decision-making at the river basin scale. Critics have suggested that rescaling, decentralization, and participatory governance mechanisms – supposedly intended to render decision-making more equitable, accessible, and relevant – can serve to legitimate, facilitate, and thus further embed processes of neoliberalization. Examining the impact of Brazil’s water sector reforms on the state–society relationship, this article presents a case study of water governance in the São Francisco River Basin and finds that the reforms – despite their neoliberalizing potential – have not significantly contributed to the neoliberalization of governance therein. Instead, water governance continues to be characterized by longstanding patterns of traditional elite control. Through an institutional and socio-natural analysis, this article describes and accounts for the continued dominance of these patterns relative to neoliberalization and explores activists’ efforts to use water sector reforms to pursue more progressive possibilities. The article concludes with a discussion of the implications for variegation and contestation in ongoing debates over neoliberal natures.  相似文献   

17.
This paper uses the concept of “grantocracy” as an analytic to understand a form of governance through grant-making by state actors as one aspect of the reregulation wrought by neoliberalization of the state. We explore this idea through a case study of conservation grant making in the Keweenaw Peninsula of Michigan’s Upper Peninsula, a highly rural and remote forestry-dependent economy. Grantocracy requires the disaggregation and rescaling of the public good, as grants are provided to address specific problems and provide single-purpose solutions. We found that while grants were intended for single purposes, in practice the use of partnerships and matching funds espoused by these programs resulted in funding programs being recombined in often conflicting and unstable ways. Moreover, limited transparency in the grant-making process restricted opportunities for public input and has helped to elide the role of the state in land conservation, undermining democratic environmental governance. This further promotes a neoliberal ideology that government is the problem, never the solution. Many of these difficulties, we conclude, arise from reliance upon the territorial strategy of private property to achieve land conservation goals.  相似文献   

18.
The results of electromagnetic sounding of the Earth??s crust in the vicinities of the SG-6 and SG-7 superdeep boreholes (Yamal-Nenets Autonomous Okrug) are presented. The studies were conducted in the fields of natural sources (AMT-MTS) and in the field of the Zevs ULF antenna located at a distance of more than 2000 km from the receiver points. In the vicinity of the SG-7 superdeep borehole, where the small industrial noise was observed, the results of inverse problem solution are completely consistent with the electric logging data. The conducting layers have been identified at the depths of 150 m and 1.1 km. The roof of rocks having small electrical conductivity and belonging to the Permian-Triassic trappean complex has been found at the depth of about 7 km. The response of the Zevs signal (the frequency range of 44?C182 Hz) has indicated the properties of the upper part of the geoelectrical section better than audiomagnetotelluric sounding for both boreholes. Based on the sounding in the vicinity of the SG-6 superdeep borehole, with the data of the Novosobirsk observatory taken into account, the distribution of resistivity down to about 800 km depth has been obtained. This distribution can serve as additional information in calculation of the temperature and rheological regime of the lithosphere and the upper mantle in the region of Western Siberia.  相似文献   

19.

The paper introduces a three-dimensional numerical technique to assess typhoon hazards in China coastal regions based on a series of full-set numerical meteorology simulations. The boundary and initial conditions of the simulations are provided by adding pseudorandom fluctuations, which represent the localized, short-term meteorological variations, to synoptic fields, which show the large-scale, long-term meteorological patterns. A series of bogus typhoons are inserted into the initial field to provide the “seeds” from which the artificial typhoons could grow. The initial positions and intensities of the bogus typhoons are drawn from the random variables whose statistics agree with those derived from historical typhoon track data. In the present study, 1503 full-set meteorology simulations of artificial typhoons are conducted. The extreme wind speeds versus return periods calculated from the simulation results are compared to not only the specifications in the load code, but also the results from the previous studies. It is found that the extreme wind speeds in the Pearl-River Delta are, contradicting to the common expectation, higher than at the mainland side of the Taiwan Strait, which imply that the typhoons hitting Guangdong are, on average, more intense than those influencing Fujian. Given the possibility to improve the three-dimensional meteorology model in the future, the simulation technique proposed in the present study provides a novel direction to assess the meteorological hazards, including threads posted by typhoons.

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20.
Through the lens of the dancing body, this paper examines practices of health and wellbeing produced in response to City of Vancouver urban governance policies. In particular, it calls attention to the legislative onslaught by city government in the years abutting the 2010 Winter Olympics to cultivate and manage healthy people, communities, and environments. In an effort to sell Vancouver’s ‘liveability’, I argue City of Vancouver endorsed a new legislative alliance that merged a conspicuously Anglo-American wellbeing lexicon, favouring individual responsibility and self-governance, with the performing arts industries. Drawing upon interviews and performance-based research, the paper illustrates how Karen Jamieson’s community dance project Connect, created for the In the Heart of the City festival, embodies Vancouver’s tri-level legislative ambitions to nurture A Healthy City For All. This materialised through the crafting of a dance-health body practice (healthy people), by choreographing a sense of belonging among ‘at risk’ communities (healthy communities), and in the uniting of the arts and health professions in the process of ‘cleaning up’ disenfranchised neighbourhoods (healthy environments). In bringing together scholarship on cultures of wellbeing and creative dance practice, the article contributes to understandings of how the health-seeking subject is embodied and performed. It also offers a productive critique of the exclusionary nature of urban health legislation, and of the contested role artists and arts festivals can play in nurturing urban wellbeing and normalising inequalities.  相似文献   

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