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1.
Scholars who have critically analyzed the commodification of nature have explored how the specific biophysical features of the objects to be commodified can shape the outcome of the commodification process. Thus, the establishment and behavior of a market system is closer to a political struggle than it is a simple technical and spontaneous process. Despite their contributions, these approaches have not focused on the resistance that cultural exegesis, self-identification, and the affective connection between the human and non-human pose to market systems. In this paper, I show how the Atacameño people from the Atacama Desert (Chile) have subverted the radical pro-water market model imposed by the Chilean military dictatorship in 1981 by relying on their water-related cultural values. In some Atacameño communities, the water market has not operated to ensure that water rights are put to those uses with the highest economic value (e.g., mining or urban water consumption). Indeed, in these communities, internal rules both forbid the sale of water rights to the mining sector and regulate the distribution of water within the community in terms that operate as barriers to other transactions. These rules form part of a moral economy of water that is a concrete ethic based on shared values and affective connections between humans and non-humans, mandating how people should relate to one another in relation to water. Together, these relations have decommodified water and contradict the neoliberal explanation of how a free water market should work.  相似文献   

2.
This paper critically examines the role of farmers’ markets in Australian agriculture. A case study is undertaken in South Australia, where all stallholders at three farmers’ markets situated in Adelaide, Willunga and Berri were surveyed regarding their production and marketing techniques. Overall responses supported literature highlighting the importance of farmers’ markets to the producers who chose to exploit this marketing niche. A strong co-reliance on ‘wholesale sales’ was also recognised, suggesting an important integration of productivist and post-productivist approaches to agricultural development. Of most promise for long-term agricultural sustainability was evidence that certain groups of farmers were found to be realising the potential of these and other alternative markets, in terms of their risk reducing capacity, and diversifying to include various conservation values into their agricultural enterprises. These groups were less concerned about market fluctuations and more concerned with issues of social equity, environmental health and having fun, which meant they unwittingly epitomised the goals of political ecology, by challenging the dominant agricultural methods of production and marketing. It seems these groups also recognised that the direct nature of their transactions would sow beneficial social, environmental and economic ‘seeds’ for change. Finally, it is argued that policies to improve access to farmers’ markets and reduce the cost of participation would assist small scale Australian agricultural producers to evolve smoothly into a multifunctional era.  相似文献   

3.
A multivariate probability transformation between random variables, known as the Nataf transformation, is shown to be the appropriate transformation for multi-Gaussian kriging. It assumes a diagonal Jacobian matrix for the transformation of the random variables between the original space and the Gaussian space. This allows writing the probability transformation between the local conditional probability density function in the original space and the local conditional Gaussian probability density function in the Gaussian space as a ratio equal to the ratio of their respective marginal distributions. Under stationarity, the marginal distribution in the original space is modeled from the data histogram. The stationary marginal standard Gaussian distribution is obtained from the normal scores of the data and the local conditional Gaussian distribution is modeled from the kriging mean and kriging variance of the normal scores of the data. The equality of ratios of distributions has the same form as the Bayes’ rule and the assumption of stationarity of the data histogram can be re-interpreted as the gathering of the prior distribution. Multi-Gaussian kriging can be re-interpreted as an updating of the data histogram by a Gaussian likelihood. The Bayes’ rule allows for an even more general interpretation of spatial estimation in terms of equality for the ratio of the conditional distribution over the marginal distribution in the original data uncertainty space with the same ratio for a model of uncertainty with a distribution that can be modeled using the mean and variance from direct kriging of the original data values. It is based on the principle of conservation of probability ratio and no transformation is required. The local conditional distribution has a variance that is data dependent. When used in sequential simulation mode, it reproduces histogram and variogram of the data, thus providing a new approach for direct simulation in the original value space.  相似文献   

4.
Governments and development organisations consider the involvement of poor forest managers in global value chains and markets as a most promising approach for resolving the social and environmental challenges of the Amazon. This paper intends to provide a clearer picture about opportunities and potentials of this market-approach, by analysing integrated forest based development initiatives in the Bolivian, Brazilian, Ecuadorian and Peruvian Amazon. Findings suggest that the externally promoted initiatives seldom correspond to local realities and that they suffer from limited financial viability due to competitive disadvantages of locals in comparison to more capitalized actors. Success stories remain isolated without replication, and depend on external support for continuation. Only a limited number of families provided with privileged support have been able to overcome the technical, institutional and financial hurdles and to benefit from existing market opportunities. In some cases, interventions have generated conflicts and even weakened social organisation. Instead of simply copying the mistakes of the past regarding the emerging markets for environmental services, it is deemed essential to question the current market focus and search for alternatives placing greater emphasis on the interests, cultures and capacities of local people.  相似文献   

5.
6.
The Castellón Plain alluvial aquifer, Spain, is intensively exploited to meet the demand for agricultural irrigation and industrial water supply. The geochemistry of its groundwater shows complex salinization in the northern and southern parts of the aquifer, with significant pollution from human origin in the central portion. Boron content and B isotope geochemistry are useful for distinguishing between various sources of pollution and their relative importance in different parts of this aquifer. Boron concentrations in the groundwater vary between 0.01 and 0.85 mg/L. In the more saline groundwaters, found at the northern and southern ends of the study area, the presence of B is linked to inputs from seawater and water with a calcium-magnesium sulphate facies, which feed the aquifer and clearly influence the chemistry of its waters. Evidence of B adsorption processes in some samples is shown by the low B/Cl ratios and the high values of δ11B. In the central portion of the aquifer, the high B/Cl ratios and the strongly negative δ11B are related to pollution of human origin.  相似文献   

7.
The program Simulation of Hydrological Extreme Events provides a set of functionalities that combined together allows constructing, manipulating, analyzing and comparing the hydrological processes involved in flash flood generation. The program makes use of existing databases of interest in hydrology and available in Spain, such as digital terrain models, coverage of rainfall or curve number. Two pilot watersheds from Spain were selected, Arás and Aguilón, where flash flood episodes have taken place. A sensitivity analysis of the flash flood episodes in response to changes in the main hydrological processes involved has been made, such as spatial and temporal distribution of rainfall, soil moisture status and water flow through channel network. In this work, we found that the antecedent moisture condition is the most influential factor in the magnitude of flash floods produced by the same amount of rain. The temporal distribution of the storm represents the second characteristic in order of relevance. In addition, terrain morphology (specially the slope) is found to be decisive in the results differences obtained.  相似文献   

8.
The insoluble organic matter of the carbonaceous meteorites contains radicals having a polyaromatic structure and a heterogeneous distribution. By using Hyperfine Sublevel Correlation spectroscopy (HYSCORE) in pulsed Electron Paramagnetic Resonance (pulsed-EPR), whereby nuclear frequencies of magnetic nuclei and their hyperfine interaction with electron spin of radicals are detected with high resolution, the radicals are shown to be considerably enriched in deuterium in the Orgueil meteorite, with a D/H ratio of 1.5 ± 0.5 × 10−2. These radicals hold 3.6 ± 1.2 × 10−3 H relative to total organic H.Analysis of hydrogen and deuterium hyperfine interactions indicates that the deuterium atoms are localized in the benzylic position, on aliphatic carbons bonded to aromatic radical moieties. This type of C-H bond exhibits one of the smallest bond energy, reinforcing the recent finding that the lower the C-H bond energy the higher the deuterium-enrichment (Remusat L., Palhol F., Robert F., Derenne S. and France-Lanord C. (2006) Enrichment of deuterium in insoluble organic matter from primitive meteorites: a solar system origin? Earth Planet. Sci. Lett.243, 15-25). Such a behavior is difficult to reconcile with the usual interpretation according to which high D/H ratios represent survivals of interstellar grains. More likely, the deuterium-enrichment process took place after the formation of organic grains whose initial isotopic compositions was close to the protosolar D/H ratio. These grains were possibly loaded at the surface of the protosolar disk where they exposed to the intense solar UV irradiation, triggering an isotopic exchange with deuterium-rich highly reactive ions.  相似文献   

9.
10.
The Almadén district constitutes the largest and probably the most intriguing mercury concentration in the world. Two types of mineralization are recognized: 1) stratabound, of Lower Silurian age, well represented by the large Almadén deposit; and 2) fully discordant mercury deposits of minor importance in terms of size, and exemplified by the deposit of Las Cuevas. The latter ones can be found at different positions along the Almadén stratigraphic column. Both types of deposits are always associated with the so-called frailesca rocks (diatremes of alkali basaltic composition). This paper reports the first lead isotope compositions of cinnabar in the district. Whole samples and stepwise leaching cinnabar aliquots display relatively homogeneous isotopic compositions (206Pb/204Pb = 18.112–18.460; 207Pb/204Pb = 15.635–15.705; 208Pb/204Pb = 38.531–38.826). Taken together with Jébrak et al.s (2002) pyrite lead isotope results, the new cinnabar isotopic data define a steep array trend on the 207Pb/204Pb– 206Pb/204Pb diagram, indicating a mixed contribution of lead and probably mercury from different sedimentary sources in the Almadén basin. The Almadén Hg deposits are related to a contemporaneous mafic magmatism that might have provided part of the mercury. Hydrothermal leaching of organic matter from sedimentary rocks and formation of Hg organic complexes enhanced metal solubility, promoting transport from and within the volcanic units.Editorial handling: M. Chiaradia  相似文献   

11.
This paper chronicles the rhetorical mechanisms that fostered a potentially radical re-thinking of water rights and property in a most unlikely place: the libertarian Western U.S., and mobilized by the least likely of actors: state officials. There is growing interest, in geography and beyond, in the question of what constitutes the “properly political” in contexts where dissent is actively forestalled by those with power. Much has been written about the “properly political” as the disruption of the established order by previously excluded actors. Comparatively less research, however, has focused on the “conditions of possibility” that might exist within ostensibly “post-political” governing arenas. This paper deepens our understanding of this by examining a participatory water planning group in Montana, which was convened by the state to develop recommendations for a new state water plan. The group was inspired by an alternative drought-management model called “shared giving.” Imbued with principles of “collectivism” and “equality,” the model was strategically (and necessarily) promoted through the discursive shell of the existing prior appropriation system. This was accomplished not by an oppositional force of marginalized actors, but state officials that are rarely, if ever, deemed “disruptive,” and through tactics that are best characterized as post-political. We interpret this case as reflecting a hybrid governing assemblage that highlights both post-political closure and transformative possibilities simultaneously, and conclude by suggesting that the post-political concept, itself, risks foreclosing on conditions whereby fruitful outcomes might become possible from within established governing frameworks otherwise written-off as post-political.  相似文献   

12.
Jian  Wei  Liang  Dongfang  Shao  Songdong  Chen  Ridong  Liu  Xingnian 《Natural Hazards》2015,78(1):531-553
Natural Hazards - The mixing process of upstream and downstream waters in the dam break flow could generate significant ecological impact on the downstream reaches and influence the environmental...  相似文献   

13.
The gneisses and metabasites of the Sierra de Limón Verde were investigated by P–T–t determinations. The rocks are unique in the Central Andes because of their high pressure metamorphic conditions with P≈13±1 kbar at T≈660–720°C. Their age of metamorphism is ≈270 Ma, based on Sm–Nd mineral isochrons. Final uplift of the isolated basement block occurred in the Triassic with a K–Ar age of biotite at ca 235 Ma. In our interpretation, the protolith of the Permian metamorphic rocks is the crust that formed and stabilized during Early Paleozoic. The Sierra de Limón Verde rocks give insight into the lowermost part of the crust in Early Mesozoic. Its Sm–Nd isotopic composition is indistinguishable from the composition of the crust that formed in the Early Paleozoic metamorphic–magmatic cycle (ca 500 Ma) in northern Chile and NW Argentina. The tectonic-geodynamic setting that triggered the high P (∼45 km depth) metamorphism and the locally restricted exhumation of the rocks remains speculative. Continental collision or a subduction related accretionary complex is unlikely considering the regional geological situation. Transpression–transtension in a strike slip system along the continental margin is suggested as a hypothesis for future investigations.  相似文献   

14.
Prospectivity mapping is used to define favorable areas for mineral exploration. The location–allocation modeling can help in ranking exploration zones for high-volume low-price industrial minerals. This type of minerals are said to have a high place-value, meaning that they derive much of their value from the fact that extraction points are located close to the demand points. With this aim, a GIS-based location–allocation model of the gypsum resources in Spain is presented in this paper. Results point to the recognition of the most interesting areas that should be investigated and places where new gypsum facilities could be located. Moreover, the model allows evaluation of the relative economic interest of the new areas as compared with the existing ones.Based on this modeling, the geological regions with the greatest potential to place new facilities are located in the northwestern (Cantabrian zone) and north-eastern (easternmost Catalonia) parts of the Iberian Peninsula, with potential market share values higher than 5.25%. Most of the economically interesting gypsum bearing units in these regions are of Mesozoic age, although Neogene deposits of the central part of Catalonia are not ruled out. In addition, the prospectivity analysis map leads to establish an area where the excess of gypsum factories results in a drastic decrease of the market share value within this region (< 1.84 %).The maps obtained with this prospectivity analysis help in the area selection and the target identification phases of a mineral exploration. The model could easily be used for other similar high place-value industrial minerals and rocks.  相似文献   

15.
16.
One of the bases of sustainable development is the responsible management of natural resources, and this is the approach which has been adopted by developed countries as regards management of all kinds of waste, through the establishment of management strategies based on prevention, reuse and recycling. This article present the results of a physical, chemical and geotechnical characterization of colliery spoils stored in slag heaps in the Ciñera-Matallana coal mining area in León, Spain. The primary objectives of this research were to determine the suitability of this mining waste for use as granular material in rural and civil engineering infrastructures and to classify it according to national and international road construction standards. On the basis of the results obtained, they are proposed several possible uses (foundation and core layers in track and road embankments, granular sub-base for light traffic and top layers of embankments), although it should be noted the need for mechanical treatments as crushing or sieving and the recommendation of use of sulphate resistant cement to avoid the possible problems.  相似文献   

17.
Pliocene intrusions in Eocene, Oligocene, and Pliocene volcanic-sedimentary rocks of the eastern Nakhichevan A. S. S.R. are of three principal types: 1) a single central cutting massif; 2) central massif with conformable apophyses; 3) conformable apophyses almost camouflaging a broken up central massif. All three are explained by differences in the morphology and tectonics of the enclosing rocks. Similarities and differences between minor intrusions and salt, gypsum, and clay diapir phenomena are discussed. ‐ ‐ Auth.  相似文献   

18.
19.
The chemical and isotopic characterization of formation water from 18 oil production wells, extracted from 5200 to 6100 m b.s.l. at the Jujo–Tecominoacán carbonate reservoir in SE-Mexico, and interpretations of historical production records, were undertaken to determine the origin and hydraulic behavior of deep groundwater systems. The infiltration of surface water during Late Pleistocene to Early Holocene time is suggested by 14C-concentrations from 2.15 to 31.86 pmC, and by 87Sr/86Sr-ratios for high-salinity formation water (0.70923–0.70927) that are close to the composition of Holocene to modern seawater. Prior to infiltration, the super-evaporation of seawater reached maximum TDS concentrations of 385 g/L, with lowest δ18O values characterizing the most hypersaline samples. Minor deviations of formation water and dolomite host rocks from modern and Jurassic 87Sr/86Sr-seawater composition, respectively, suggest ongoing water–rock interaction, and partial isotopic equilibration between both phases. The abundance of 14C in all sampled formation water, 87Sr/86Sr-ratios for high-salinity water close to Holocene – present seawater composition, a water salinity distribution that is independent of historic water-cut, and a total water extraction volume of 2.037 MMm3 (1/83–4/07) excludes a connate, oil-leg origin for the produced water of the Jurassic–Cretaceous mudstone-dolomite sequence. Temporal fluctuations of water chemistry in production intervals, the accelerated migration of water fronts from the reservoir flanks, and isotopic mixing trends between sampled wells confirms the existence of free aquifer water below oil horizons. Vertical and lateral hydraulic mobility has probably been accelerated by petroleum extraction.  相似文献   

20.
The origin and evolution of formation water from Upper Jurassic to Upper Cretaceous mudstone–packstone–dolomite host rocks at the Jujo–Tecominoacán oil reservoir, located onshore in SE-Mexico at a depth from 5200 to 6200 m.b.s.l., have been investigated, using detailed water geochemistry from 12 producer wells and six closed wells, and related host rock mineralogy. Saline waters of Cl–Na type with total dissolved solids from 10 to 23 g/L are chemically distinct from hypersaline Cl–Ca–Na and Cl–Na–Ca type waters with TDS between 181 and 385 g/L. Bromine/Cl and Br/Na ratios suggest the subaerial evaporation of seawater beyond halite precipitation to explain the extreme hypersaline components, while less saline samples were formed by mixing of high salinity end members with surface-derived, low salinity water components. The dissolution of evaporites from adjacent salt domes has little impact on present formation water composition. Geochemical simulations with Harvie-Mφller-Weare and PHRQPITZ thermodynamic data sets suggest secondary fluid enrichment in Ca, HCO3 and Sr by water–rock interaction. The volumetric mass balance between Ca enrichment and Mg depletion confirms dolomitization as the major alteration process. Potassium/Cl ratios below evaporation trajectory are attributed to minor precipitation of K feldspar and illitization without evidence for albitization at the Jujo–Tecominoacán reservoir. The abundance of secondary dolomite, illite and pyrite in drilling cores from reservoir host rock reconfirms the observed water–rock exchange processes. Sulfate concentrations are controlled by anhydrite solubility as indicated by positive SI-values, although anhydrite deposition is limited throughout the lithological reservoir column. The chemical variety of produced water at the Jujo–Tecominoacán oil field is related to a sequence of primary and secondary processes, including infiltration of evaporated seawater and original meteoric fluids, the subsequent mixing of different water types and the formation of secondary minerals by water–rock interaction. A best fit between measured and calculated reservoir temperatures was obtained with the Mg–Li geothermometer for high salinity formation water (TDS > 180 g/L), whereas Na–K, Na–Ka–Ca and quartz geothermometers are partially applicable for less salinite water (TDS < 23 g/L).  相似文献   

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