共查询到20条相似文献，搜索用时 548 毫秒
1.
B. L. Turner II 《Geoforum》2002,33(4):427-429
Reviews and observations about the status of the discipline of geography, no matter how positive, invariably raise programmatic concerns. These concerns have a long history that arise from geography's struggles to find an identity that embraces its many parts and yet are consistent with the logic by which the academy partitions knowledge. Pedagogy and research historically claimed by geography is currently being reinvented and relabeled under such headings as “integrated environmental science” and “spatial science”, and these developments have the potential to change the breadth of the “geographic imagination”. Several observations about dominant explanatory perspectives and substantive domains of geographic enquiry are also provided. 相似文献
2.
Yuzhuang Sun 《International Journal of Coal Geology》2003,56(3-4):269-276
Although “barkinite” has long been studied by many geologists, its geochemical characteristics and environment of deposition are still not known in detail. In order to study the petrography and geochemical characteristics of “barkinite”, coal samples from two Permian coal seams were taken from the Dahe mine, Guizhou Province. The samples were separated into maceral fractions, and then analyzed by microscopical, isotopic, Rock-Eval, and geochemical methods. The microscopical results indicate that “barkinite” occurs as four main types. According to their relationship to other maceral groups, “barkinite” is ostensibly formed under variably dry–wet or oxidizing–reducing conditions. The extract yield, isotope data and Rock-Eval values of “barkinite” are different from other macerals. Microscopical and geochemical results indicate that “barkinite” forms part of the liptinite group. 相似文献
3.
Natural resource investment in the mining sector is often mediated through conflicts over rent distribution between corporate capital and landowner states. Recent rounds of neoliberal policy promoted by the World Bank have highlighted the need for landowner states to offer incentives in order to attract “high risk” capital investment. In Sub-Saharan Africa, in particular, countries have been pushed to offer attractive fiscal terms to capital, thereby lowering the proportion traditionally called rent. This paper examines how the concept of “risk” has been mobilized to legitimate such skewed distributional arrangements. While certain conceptions of social and ecological “risk” have been prevalent in political and social theoretic discourse on mining, such focus elides the overwhelming contemporary power of our notion of “neoliberal risk” – or the financial/market risks – in actually setting the distributional terms of mineral investment. We illustrate our argument by examining the nexus of World Bank mining policy promotion and Tanzanian policy in the late 1990s meant to attract foreign direct investment in gold production. In closing, we suggest that just as “risk” is used to legitimate attractive fiscal terms for investment, recent events highlight how skewed distribution of benefits may set into motion risks that corporate capital had not bargained for. 相似文献
4.
Andrea Nightingale 《Geoforum》2003,34(4):525-540
This paper presents a theoretical framework for analyzing human–environment issues that examines shifting, dialectical relationships between social and power relations, cultural beliefs and practices, and ecological processes to allow an interdisciplinary, complex assessment of social and environmental change in Nepal. The purpose of this analysis is to capture the complexity and non-static nature of environmental and social change in the context of uneven development. Drawing from political ecology and feminist geography, this framework brings together scholarship on aspects of human–environment issues that are often pursued in isolation, yet all three processes, social–political relations, cultural practices and ecological conditions, have been acknowledged as important in shaping the trajectory of social and ecological change. I argue that a consideration of the articulations between them is necessary to understand first, how specific land management regimes arise and are dominant over time in specific places. And second, I examine the extent to which these regimes distribute resources equitably within communities, promote economic development and sustain ecological resilience. In this analysis, ecological processes are conceptualised as co-productive of social and cultural processes to explore their role in land management regimes without resorting to environmental determinist or similarly reductive paradigms. I present this framework through the example of natural resource management, specifically community forestry in Nepal, as it offers a rich case study of the relationships between the political economy of land use and the ecological effects of natural resource extraction. 相似文献
5.
Digging into Google Earth: An analysis of “Crisis in Darfur” 总被引：1，自引：0，他引：1
Google publicists have suggested the Crisis in Darfur is an example of the Google Earth software’s “success at tangibly impacting what is happening on the ground.” Yet whether or not Google Earth’s interface, along with a medley of other media representations of the conflict, have impacted events on the ground or led to coherent policies of humanitarian intervention remains open to debate. This article draws upon critical approaches from media studies—namely discourse analysis—to analyze several aspects of the Google Earth/USHMM Crisis in Darfur project. While this project was no doubt developed with the noble intention of generating international awareness about widespread violence that has recently occurred in the Darfur region, it is important to evaluate how representations of global conflicts are changing with uses of new information technologies and whether such representations can actually achieve their desired impacts or effects. The article begins with a discussion of the Crisis in Darfur project’s history, proceeds to analyze some of the press coverage of the project and then moves to a critique of the layer using four categories of analysis: (1) the shifting role of satellite image; (2) the temporality of the interface; (3) the practice of conflict branding; and (4) the practice of “information intervention.” Throughout the article, I explore how the presentation of Darfur-related materials through Google Earth reproduces problematic Western tropes of African tragedy and misses an opportunity to generate public literacy around satellite images. I also consider how humanitarianism is intertwined with digital and disaster capitalism, and suggest that this instance of “information intervention” makes patently clear that high visual capital alone cannot resolve global conflicts. 相似文献
6.
Kathleen O&#x;Reilly 《Geoforum》2006,37(6):958-972
In this paper, I analyze the connections made between women and water in a Rajasthani drinking water supply project as a significant part of drinking water’s commodification. For development policy makers, water progressing from something free to something valued by price is inevitable when moving economies toward modernity and development. My findings indicate that water is not commodified simply by charging money for it, but through a series of discourses and acts that link it to other “modern” objects and give it value. One of these objects is “women”. I argue that through women’s participation activities that link gender and modernity to new responsibilities and increased mobility for village women involving the clean water supply, a “traditional” Rajasthani woman becomes “modern”. Water, in parallel, becomes “new”, “improved” and worth paying for. Women and water resources are further connected through project staff’s efforts to promote latrines by targeting women as their primary users. The research shows that villagers applied their own meanings to latrines, some of which precluded women using them. This paper fills a gap in feminist political ecology, which often overlooks how gender is created through natural resource interventions, by concerning itself with how new meanings of “water” and “women” are mutually constructed through struggles over water use and its commodification. It contributes to critical development geography literatures by demonstrating that women’s participation approaches to natural resource development act as both constraints and opportunities for village constituents. It examines an under-explored area of gender and water research by tracing village-level struggles over meanings of latrines. 相似文献
7.
Onshore–offshore seismic refraction profiling allows for the determination of crustal and mantle structures in the transition between continental and oceanic environments. Islands and narrow landmasses have the unique geometry of allowing for double-sided onshore–offshore experiments that favor the construction of composite “super-gathers” using the acquisition of onshore–offshore and ocean-bottom seismometer receiver gathers, land explosion shot gathers, and near-vertical incidence multichannel seismic (MCS) profiling. A number of sites at plate boundaries are amenable to the application of double-sided onshore–offshore imaging, including the Indo-Australian/Pacific transform boundary on South Island, New Zealand. By comparing the ratio of island width to mantle refraction (Pn) “maximum” crossover distance, using nondimensional distances, we provide an indicator of raypath “coverage” for crustal illumination. Islands or narrow land masses whose widths are less than twice their maximum crossover distance are candidates for double-sided onshore–offshore experiments. The SIGHT (South Island GeopHysical invesTigation) experiment in New Zealand is located where the width of South Island is sufficiently narrow with respect to its crustal thickness that a double-sided onshore–offshore experiment allows for complete crustal imaging of the associated plate boundary. 相似文献
8.
The “region” and “regional change” have been elusive ideas within political and economic geography, and in essence require a greater understanding of their dynamic characteristics. Trailing in the backwaters of the devolution to the Celtic nations of Britain, the contemporary era of New Labour’s political-economic ideology, manifest through “third-way” governance in England places the region and its functional capacity into the heart of geographical inquiry. Drawing upon a new regionalist epistemology, this paper seeks to recover a sense of (regional) political economy through a critical investigation of the development and formulation of Blair’s “New Regional Policy” (NRP). I address how New Labour has attempted to marry economic regionalisation on the one hand, and democratic regionalism on the other. This paper specifically questions the wisdom of such a marriage of politically distinct ideologies through a critical investigation of the underlying contradictions of their strategy from both a theoretical and empirical standpoint. Demonstrated both in the North East “no” vote in 2004, and in the post-mortem undertaken by the ODPM Select Committee in 2005, the paper illustrates how a loss of political drive gradually undermined the capacity of devolution to deliver in England. Finally, I argue that through the lens of the NRP we can speculate on some of the wider issues and implications for the study of regional governance. 相似文献
9.
Leping coal is known for its high content of “barkinite”, which is a unique liptinite maceral apparently found only in the Late Permian coals of South China. “Barkinite” has previously identified as suberinite, but on the basis of further investigations, most coal petrologists conclude that “barkinite” is not suberinite, but a distinct maceral. The term “barkinite” was introduced by (State Bureau of Technical Supervision of the People's Republic of China, 1991, GB 12937-91 (in Chinese)), but it has not been recognized by ICCP and has not been accepted internationally.In this paper, elemental analyses (EA), pyrolysis-gas chromatography, Rock-Eval pyrolysis and optical techniques were used to study the optical features and the hydrocarbon-generating model of “barkinite”. The results show that “barkinite” with imbricate structure usually occurs in single or multiple layers or in a circular form, and no definite border exists between the cell walls and fillings, but there exist clear aperture among the cells.“Barkinite” is characterized by fluorescing in relatively high rank coals. At low maturity of 0.60–0.80%Ro, “barkinite” shows strong bright orange–yellow fluorescence, and the fluorescent colors of different cells are inhomogeneous in one sample. As vitrinite reflectance increases up to 0.90%Ro, “barkinite” also displays strong yellow or yellow–brown fluorescence; and most of “barkinite” lose fluorescence at the maturity of 1.20–1.30%Ro. However, most of suberinite types lose fluorescence at a vitrinite reflectance of 0.50% Ro, or at the stage of high volatile C bituminous coal. In particular, the cell walls of “barkinite” usually show red color, whereas the cell fillings show yellow color under transmitted light. This character is contrary to suberinite.“Barkinite” is also characterized by late generation of large amounts of liquid oil, which is different from the early generation of large amounts of liquid hydrocarbon. In addition, “barkinite” with high hydrocarbon generation potential, high elemental hydrogen, and low carbon content. The pyrolysis products of “barkinite” are dominated by aliphatic compounds, followed by low molecular-weight aromatic compounds (benzene, toluene, xylene and naphthalene), and a few isoprenoids. The pyrolysis hydrocarbons of “barkinite” are mostly composed of light oil (C6–C14) and wet gas (C2–C5), and that heavy oil (C15+) and methane (C1) are the minor hydrocarbon.In addition, suberinite is defined only as suberinized cell walls—it does not include the cell fillings, and the cell lumens were empty or filled by corpocollinites, which do not show any fluorescence. Whereas, “barkinite” not only includes the cell walls, but also includes the cell fillings, and the cell fillings show bright yellow fluorescence.Since the optical features and the hydrocarbon-generating model of “barkinite” are quite different from suberinite. We suggest that “barkinite” is a new type of maceral. 相似文献
10.
The paper identifies and discusses potential adverse environmental impacts, and regulatory concerns, that could arise from piling or penetrative ground improvement techniques, when used on land affected by contamination.
A common generic classification of piling and penetrative ground improvement methods is considered and six cases are identified where potential adverse environmental impacts may be created by piling or penetrative ground improvement techniques.
A lack of published data on the scale of impacts caused by piling makes inevitable the application of the “Precautionary Principle” by environmental regulators, but it has been recognised that a rigid application of this principle may lead to unnecessarily restrictive requirements or prohibitions being placed on designers and developers. The need for guidance for designers and developers on how to consider the potential environmental impacts of piling works has also been recognised.
The paper outlines the decision-making framework presented in recent Environment Agency guidance. It assists the foundation designer to assess the environmental risks, select an appropriate piling or penetrative ground improvement method, develop mitigation measures, define quality assurance/quality control and monitoring measures, and justify and document this choice in a format acceptable to the regulator. 相似文献
11.
Krzysztof Birkenmajer Przemys&#x;aw Gedl Ryszard Myczy&#x;ski Jaros&#x;aw Tyszka 《Cretaceous Research》2008,29(3):535-549
This is a critical assessment of the paper by Oszczypko et al. (2004: Cretaceous Research 25, 89–113), in which they tried to prove a mid-Cretaceous age for the Szlachtowa (“black flysch”) and Opaleniec Formations, in the Pieniny Klippen Belt, West Carpathians, both of which had previously been shown to be of Jurassic age. We argue that the mid-Cretaceous age assignment is a misinterpretation, primarily resulting from their field samples having been collected from some Cretaceous lithostratigraphic units, tectonically associated with the Jurassic formations, and/or from tectonic contact-breccias involving Jurassic and Cretaceous strata. In addition, we suggest that they have overlooked a number of significant palaeontological papers, published since 1962, which record the presence of in situ ammonites, aptychi, belemnites, thin-shelled bivalves (Bositra), gryphaeids, foraminifera, and ostracod assemblages, all indicating a Jurassic (mainly Aalenian), and not a Cretaceous, age for the Szlachtowa Formation, and also the in situ Jurassic (Bajocian) ammonites and thin-shelled bivalves (Bositra), Bositra-microfacies, and age-diagnostic foraminiferal assemblages of the Opaleniec Formation.Our presentation here of recently published dinocyst data from well-preserved assemblages further supports the Jurassic ages for the Szlachtowa (“black flysch”) and Opaleniec Formations. 相似文献
12.
This paper examines the use of conservation easements, with a focus on California. Conservation easements are now the dominant tool used for private land conservation in the United States. Easements are in many ways a paradigmatic neoliberal environmental policy tool. They privatize and re-scale a great deal of land conservation decision-making authority; they are market-based; they provide financial incentives for participation rather than punishment for non-compliance; and they commodify new property rights. However, these neoliberalisms are incorporated in uneven, and sometimes contradictory, ways that emphasize the gulf between neoliberal ideologies and “actually existing neoliberalisms.” Most critically, as a result of extensive public funding and management, conservation easements are not nearly as private (and thus not as neatly neoliberal) as they sometimes seem. Conservation easements are often heralded as a “win–win” land conservation strategy. I argue that the extent to which conservation easements may be construed as win–win solutions depends a great deal on who is included in the calculation of winners and losers. I contend that using and governing easements as if they are private elides complex questions about larger public costs and benefits. This obscures the large number of people and institutions (both state and private) that will likely need to be involved in governing conservation easements in the long term. 相似文献
13.
《Geoforum》2017
Environmental security concerns have broadened the national security agenda and discourse of international relations. Yet environmental insecurity issues have endured impacts on livelihood, human security, social equity, human rights, internal security, political stability, economic growth and development of the state. Environmental challenges, such as climate change, water scarcity and energy security are shaping development and consumption patterns, which are possible causes of inter-state conflict in South Asia. This paper is an attempt to evaluate the nexus of climate change, energy and water security with conflict and development. Furthermore, we argue for the need for environmental diplomacy in Pakistan within the South Asian context. The argument is that integration of development with environmental factors and peacemaking has potential to achieve sustainable development in South Asia. 相似文献
14.
The event across the Paleozoic–Mesozoic transition involved the greatest mass extinction in history together with other unique geologic phenomena of global context, such as the onset of Pangean rifting and the development of superanoxia. The detailed stratigraphic analyses on the Permo-Triassic sedimentary rocks documented a two-stepped nature both of the extinction and relevant global environmental changes at the Guadalupian–Lopingian (Middle and Upper Permian) boundary (G-LB, ca. 260 Ma) and at the Permo-Triassic boundary (P-TB, ca. 252 Ma), suggesting two independent triggers for the global catastrophe. Despite the entire loss of the Permian–Triassic ocean floors by successive subduction, some fragments of mid-oceanic rocks were accreted to and preserved along active continental margins. These provide particularly important dataset for deciphering the Permo-Triassic paleo-environments of the extensive superocean Panthalassa that occupied nearly two thirds of the Earth’s surface. The accreted deep-sea pelagic cherts recorded the double-phased remarkable faunal reorganization in radiolarians (major marine plankton in the Paleozoic) both across the G-LB and the P-TB, and the prolonged deep-sea anoxia (superanoxia) from the Late Permian to early Middle Triassic with a peak around the P-TB. In contrast, the accreted mid-oceanic paleo-atoll carbonates deposited on seamounts recorded clear double-phased changes of fusuline (representative Late Paleozoic shallow marine benthos) diversity and of negative shift of stable carbon isotope ratio at the G-LB and the P-TB, in addition to the Paleozoic minimum in 87Sr/86Sr isotope ratio in the Capitanian (Late Guadalupian) and the paleomagnetic Illawarra Reversal in the late Guadalupian. These bio-, chemo-, and magneto-stratigraphical signatures are concordant with those reported from the coeval shallow marine shelf sequences around Pangea. The mid-oceanic, deep- and shallow-water Permian records indicate that significant changes have appeared twice in the second half of the Permian in a global extent. It is emphasized here that everything geologically unusual started in the Late Guadalupian; i.e., (1) the first mass extinction, (2) onset of the superanoxia, (3) sea-level drop down to the Phanerozoic minimum, (4) onset of volatile fluctuation in carbon isotope ratio, 5) 87Sr/86Sr ratio of the Paleozoic minimum, (6) extensive felsic alkaline volcanism, and (7) Illawarra Reversal.The felsic alkaline volcanism and the concurrent formation of several large igneous provinces (LIPs) in the eastern Pangea suggest that the Permian biosphere was involved in severe volcanic hazards twice at the G-LB and the P-TB. This episodic magmatism was likely related to the activity of a mantle superplume that initially rifted Pangea. The supercontinent-dividing superplume branched into several secondary plumes in the mantle transition zone (410–660 km deep) beneath Pangea. These secondary plumes induced the decompressional melting of mantle peridotite and pre-existing Pangean crust to form several LIPs that likely caused a “plume winter” with global cooling by dust/aerosol screens in the stratosphere, gas poisoning, acid rain damage to surface vegetation etc. After the main eruption of plume-derived flood basalt, global warming (plume summer) took over cooling, delayed the recovery of biodiversity, and intensified the ocean stratification. It was repeated twice at the G-LB and P-TB.A unique geomagnetic episode called the Illawarra Reversal around the Wordian–Capitanian boundary (ca. 265 Ma) recorded the appearance of a large instability in the geomagnetic dipole in the Earth’s outer core. This rapid change was triggered likely by the episodic fall-down of a cold megalith (subducted oceanic slabs) from the upper mantle to the D″ layer above the 2900 km-deep core-mantle boundary, in tight association with the launching of a mantle superplume. The initial changes in the surface environment in the Capitanian, i.e., the Kamura cooling event and the first biodiversity decline, were probably led by the weakened geomagnetic intensity due to unstable dipole of geodynamo. Under the low geomagnetic intensity, the flux of galactic cosmic radiation increased to cause extensive cloud coverage over the planet. The resultant high albedo likely drove the Kamura cooling event that also triggered the unusually high productivity in the superocean and also the expansion of O2 minimum zone to start the superanoxia.The “plume winter” scenario is integrated here to explain the “triple-double” during the Paleozoic–Mesozoic transition interval, i.e., double-phased cause, process, and consequence of the greatest global catastrophe in the Phanerozoic, in terms of mantle superplume activity that involved the whole Earth from the core to the surface biosphere. 相似文献
15.
An important subject of debate in the Third World is that of the application of alternative strategies of rural development. Critical examination is undertaken of the programme of betterment planning as an agency of rural development in South Africa's impoverished Black Homelands. The rhetoric of “development” obscures the fact that betterment is an important dimension of the political economy of apartheid. A detailed study of betterment planning in Lebowa reveals that the programme is associated with the growth of landlessness, reductions in land available for ploughing, the forced resettlement of large groups of people and major reductions in Africa livestock holdings. Evidence from one case study village shows that the application of betterment may transform formerly self-sufficient rural populations into communities dependent for their existence upon the debilitating migratory labour system. 相似文献
16.
Andrew Herod 《Geoforum》1999,30(4):382
Using open-ended interviews to conduct research on foreign elites raises methodological questions which conducting research on non-foreign elites and foreign non-elites does not. In this paper I first reflect upon some of the practical issues I have encountered when conducting interviews with members of foreign elites. I then examine the issue of positionality to suggest that the dualism of “insider” knowledge and status versus “outsider” knowledge and status is not as stable as it is often assumed to be, and that it should not be presumed that an “insider” will necessarily produce “better” knowledge than will an “outsider” simply by dint of their positionality. Indeed, given that the interview process is about constructing social meaning – a process that involves both the researcher and the source – in many ways such a dualism is meaningless. 相似文献
17.
Radiocaesium (137Cs) dispersion and Cs+ fixation were studied in the sediments collected from the lagoon systems of “Ria de Aveiro”. The Cs+ sorption was tested for the fine mica grains and for the < 2 μm clay fractions extracted from silty clays. The Cs+ exchange is found strongly onto mica-rich fractions than smectite-rich fractions. The distribution coefficient increases if the silty material is constituted by rich-mica clay fractions or if the non-clay minerals are removed from the silty-clay material. The samples studied behave as multisite ion exchange, where Cs+ engages in ion-exchange reactions with hydrated cations on planar sites on expansible layer silicates. Higher concentrations of the 137Cs were found associated with mica-rich silty clays. The 137Cs ranges from 3.2 to 3.9 Bq kg− 1 in the < 38 μm fractions and from 2.9 to 3.3 Bq kg− 1 in the < 64 μm fractions. 相似文献
18.
M.R. St-Onge 《Tectonophysics》1981,76(3-4)
Three progressive metamorphic suites are developed in pelitic rocks of the northern Wopmay Orogen. Two suites are related to the Hepburn Batholith and one to the Wentzel Batholith. All three suites are cut by post-metamorphic wrench faults, some of which have significant vertical displacement. The structural relief so provided reveals that medium-and high-grade isograds associated with the Hepburn Batholith dip inward towards the batholith and are thus “hot-side-up”. Isograds associated with the Wentzel Batholith dip away from the batholith and are thus “hot-side-down”. It is concluded that Hepburn Batholith has the form of the flattened funnel fed from depth, and that Wentzel Batholith is the arched roof of an intrusive complex of unknown shape at depth. 相似文献
19.
W.E. Krumbein 《Precambrian Research》1983,20(2-4)
Several definitions of stromatolites are discussed and Kalkowsky's most important statements about stromatolites are translated from German to English. A new definition for stromatolites is proposed, namely “Stromatolites are laminated rocks, the origin of which can clearly be related to the activity of microbial communities, which by their morphology, physiology and arrangement in space and time interact with the physical and chemical environment to produce a laminated pattern which is retained in the final rock structure”. Unconsolidated laminated systems, clearly related to the activity of microbial communities and often called “recent stromatolites” or “living stromatolites”, are defined as “potential stromatolites”.The main microbial activities which are important in the formation of potential stromatolites and stromatolites are described and examples of stromatolites of various types, including iron stromatolites, are also described. 相似文献