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181.
This paper questions Geographers debates about ‘caring at a distance’ and the ‘geographies of responsibility’, focussing on the treatment of the theme of partiality in ethics and justice. Debates in Geography often present partial commitments as morally or politically problematic on the grounds that they prioritize self-interest, exclusionary, and geographically restricted ways of relating to others. We outline how debates about caring at a distance and the geographies of responsibility frame partiality as a problem to be overcome. We argue that Geography’s engagements with moral philosophy are premised on faulty assumptions about the sorts of influences people are liable to act upon (one’s that privilege causal knowledge as the primary motivating force), and also flawed assumptions about the sorts of problems that academic reasoning about normative issues is meant to address (the assumption that people are too egoistical and not altruistic enough). We use the theme of generosity as an entry point to argue that partiality and finitude might be the conditions for any ethical–political project that de-centres the motivation of practical action away from the sovereign self towards responsive and attentive relations of encounter with the needs of others. Understanding generosity as a modality of power suggests a revised programme for geographical investigations of the intersection between ethics, morality and politics: one which looks at how opportunities to address normative demands in multiple registers are organized and transformed; at the ways in which dispositions to respond and to be receptive to others are worked up; and how opportunities for acting responsively on these dispositions are organized. 相似文献
182.
The liberalisation of agricultural markets is one of the most contested issues in international politics. Debates surrounding it counter-pose the moral imperative to dismantle protectionist agricultural subsidies in order to combat rural poverty in the South with fears for the livelihoods of marginal farmers and the environmental integrity of the countryside in the developed North. A largely European concern with defending the ‘multifunctionality’ of agriculture is dismissed by critics as a protectionist excuse for continued farm support. In this paper we seek to assess how far support for multifunctionality can be construed as a form of resistance to the neoliberal project for agriculture. The paper begins with an analysis of the European negotiating stance in the Doha round and the subsequent evolution of debates surrounding multifunctionality in an international setting. Having identified the European Union as one of the key sites of articulation concerning the implications of trade liberalisation for a multifunctional agriculture, the paper goes on to argue that multifunctionality within the framework of European rural policy emerges as a much more elusive and susceptible concept, informed by radically different interpretations of the vulnerability of family farmers to greater market exposure and the extent to which agricultural restructuring should be regarded as an issue of wider public concern. This maps onto a technically complex debate about how best to procure environmental public goods in a period of rapid agricultural change. The paper concludes that with these differences still very much in play, questions concerning the compatibility of multifunctionality with market liberalisation remain deeply unresolved at an important moment in the internationalisation of rural policy governance. 相似文献
183.
The continuing use of petrochemicals in mineral nitrogen(N) production may be affected by supply or cost issues and climate agreements.Without mineral N,a larger area of cropland is required to produce the same amount of food,impacting biodiversity.Alternative N sources include solar and wind to power the Haber-Bosch process,and the organic options such as green manures,marine algae and aquatic azolla.Solar power was the most land-efficient renewable source of N,with using a tenth as much land as wind energy,and at least 100 th as much land as organic sources of N.In this paper,we developed a decision tree to locate these different sources of N at a global scale,or the first time taking into account their spatial footprint and the impact on terrestrial biodiversity while avoiding impact on albedo and cropland,based on global resource and impact datasets.This produced relatively few areas suitable for solar power in the western Americas,central southern Africa,eastern Asia and southern Australia,with areas most suited to wind at more extreme latitudes.Only about 2% of existing solar power stations are in very suitable locations.In regions such as coastal north Africa and central Asia where solar power is less accessible due to lack of farm income,green manures could be used,however,due to their very large spatial footprint only a small area of low productivity and low biodiversity was suitable for this option.Europe in particular faces challenges because it has access to a relatively small area which is suitable for solar or wind power.If we are to make informed decisions about the sourcing of alternative N supplies in the future,and our energy supply more generally,a decision-making mechanism is needed to take global considerations into account in regional land-use planning. 相似文献
184.
Clive M. Rice Richard J. McCoyd Adrian J. Boyce Peter Marchev 《Mineralium Deposita》2007,42(7):691-713
The Madjarovo ore district is centred on the exposed section of a Lower Oligocene volcano and consists of radially disposed
Pb–Zn-precious metal veins and attendant intermediate sulfidation wallrock alteration. Earlier high sulfidation and potassic
porphyry style alterations are found in the centre of the district spatially associated with monzonitic intrusions. The total
duration of all mineralization and alteration was ca. 300 ka. Stable isotope analyses (S, O, H) have been carried out on a
suite of sulfides, sulfates and silicates from the mineralization, high and intermediate sulfidation alterations and a suite
of basement rocks. These data range between the following limits: . We also analysed δD of fluid inclusions in quartz and barite for which we obtained, respectively, the ranges of −43.6 to −78.6 and −58.4 to −67.1‰.
The data show that high sulfidation alteration was dominated by magmatic fluids with minor meteoric water, whereas the fluids
responsible for the intermediate sulfidation alteration were essentially magmatic. The fluids responsible for the intermediate
sulfidation Pb–Zn mineralization were mixed magmatic–meteoric and certainly contained a significant meteoric component. Sulphur
is likely derived from basement and/or igneous sources. The evolution of alteration and mineralization styles from potassic,
porphyry copper style to high sulfidation to intermediate sulfidation can be understood in terms of changing ore fluid composition
resulting from an increasing permeability of the system and an increasingly remote source of magmatic fluid with time. These
changes link directly to the geological evolution of this volcanic centre. 相似文献
185.
Stephen M. Elardo Charles K. Shearer Jr. Amy L. Fagan Lars E. Borg Amy M. Gaffney Paul V. Burger Clive R. Neal Vera A. Fernandes Francis M. McCubbin 《Meteoritics & planetary science》2014,49(2):261-291
Northwest Africa (NWA) 4734 is an unbrecciated basaltic lunar meteorite that is nearly identical in chemical composition to basaltic lunar meteorites NWA 032 and LaPaz Icefield (LAP) 02205. We have conducted a geochemical, petrologic, mineralogic, and Sm‐Nd, Rb‐Sr, and Ar‐Ar isotopic study of these meteorites to constrain their petrologic relationships and the origin of young mare basalts. NWA 4734 is a low‐Ti mare basalt with a low Mg* (36.5) and elevated abundances of incompatible trace elements (e.g., 2.00 ppm Th). The Sm‐Nd isotope system dates NWA 4734 with an isochron age of 3024 ± 27 Ma, an initial εNd of +0.88 ± 0.20, and a source region 147Sm/144Nd of 0.201 ± 0.001. The crystallization age of NWA 4734 is concordant with those of LAP 02205 and NWA 032. NWA 4734 and LAP 02205 have very similar bulk compositions, mineral compositions, textures, and ages. Their source region 147Sm/144Nd values indicate that they are derived from similar, but distinct, source materials. They probably do not sample the same lava flow, but rather are similarly sourced, but isotopically distinct, lavas that probably originate from the same volcanic complex. They may have experienced slightly different assimilation histories in route to eruption, but can be source‐crater paired. NWA 032 remains enigmatic, as its source region 147Sm/144Nd definitively precludes a simple relationship with NWA 4734 and LAP 02205, despite a similar bulk composition. Their high Ti/Sm, low (La/Yb)N, and Cl‐poor apatite compositions rule out the direct involvement of KREEP. Rather, they are consistent with low‐degree partial melting of late‐formed LMO cumulates, and indicate that the geochemical characteristics attributed to urKREEP are not unique to that reservoir. These and other basaltic meteorites indicate that the youngest mare basalts originate from multiple sources, and suggest that KREEP is not a prerequisite for the most recent known melting in the Moon. 相似文献
186.
We present a synthesis of CMIP5 model results for projected rainfall changes for a single region (south-east Queensland, Australia) and note that, as was evident in CMIP3 results, the multi-model mean projected changes for the late 21st century are not statistically significant for any season nor annually. Taking account of the number of statistically significant changes to mean rainfall, we find some evidence favouring a decrease in both spring and annual rainfall, but this is not compelling. In almost all cases the most frequent result is for no significant change. However, if we consider the number of results where there is a statistically significant change in the distributions of rainfall amounts, there appears to be slightly more information available for risk assessment studies. These numbers suggest an increase in the frequency of both wet and dry events during summer and spring, and a shift towards more frequent dry events during winter. There is no evidence for any significant changes to the distributions for either autumn or annually. The findings suggest that, in one respect, multi-model rainfall projections may contain more information than is evident from syntheses which focus on changes to the means and that, for some regions where changes in the frequency of wet and dry seasons/years have known impacts, the model projections may be more valuable than previously thought. 相似文献
187.
Characterization and source of oil contamination on the beaches and seabird corpses, Sable Island, Nova Scotia, 1996-2005 总被引:1,自引:0,他引:1
During April 1996-May 2005, 2343 oiled seabird corpses were recorded in beach surveys conducted on Sable Island, Nova Scotia. One hundred eighty-three samples of oil were collected from the beaches and from the feathers of bird corpses. Gas chromatographic (GC/FID) analysis was used to identify generic oil type and likely marine source. During this period, at least 74 marine oil discharge events were probably responsible for beached pelagic tar and contamination of seabird corpses found on Sable Island, of which 77.0% were crude oils, 14.9% were fuel oils, and 8.1% were bilge oil mixtures. While fuel and bilge oils may be discharged by all vessel and platform types, crude oil discharges are associated with tanker operations. This study demonstrates that oiling of the sea from tankers remains a serious wildlife issue in the Northwest Atlantic. 相似文献
188.