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While the geopolitical legacies of the World War I peace negotiations are widely recognized, this article examines the often overlooked connection between the WWI Paris Peace Conference's spatial and geopolitical logics and contemporary refugee‐border dynamics. We argue that the spatial and geopolitical logics that framed the WWI Paris Peace Conference—the creation of new states, the propagation of the Western ideal of bounded sovereign states, the nationalist goals of self‐determination and homogeneous ethnic nations, and the establishment of a system of international governance—continue to impact refugee‐border dynamics and “crises” today. The categories, ideals, and practices of the international refugee regime that emerged over the last one‐hundred years stem in great part from these logics. In this paper, we urge critical contemplation about how these foundations—including the establishment of the post of High Commissioner for Refugees in 1921, the resultant Nansen Passports, the post‐WWI minority treaties, and lastly the 1933 Convention Relating to the International Status of Refugees—connect to contemporary human (im)mobility and border violence. We also introduce the articles in this special issue and highlight key themes and future directions for research in critical migration studies.  相似文献   
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Clay-rich mine tailings from phosphate mine operations in Florida are a major environmental and economic problem. Options for reclamation and restoration for these tailings are very limited and are fundamentally restricted by poor physical properties such as low mechanical strength, low hydraulic conductivity, and heavy metal content. The major control on these bulk physical properties is the mineralogy of the materials. Eight continuous push borings were obtained to investigate stratigraphy, mineralogy, aspects of geochemistry, and bulk properties of a deposit of clay-rich mine tailings from a phosphate mine near Bartow, Florida that ceased operations in the early 1970s. Stratigraphy is dominated by laminated clay-rich sediment with minor units of silt and sand. An intact kaolinite liner occurs near the impoundment walls and the impoundment floor has approximately 4 m of relief. Moisture content varies from 4.35 to 57.40 wt% and organic content varies from 0.41 to 9.53 wt%. Bulk XRF investigation indicates that the P2O5 concentrations vary from approximately 4 to 21 wt%. A very strong correlation (r 2 = 0.92) between CaO and P2O5 indicates that apatite is a major control on the phosphate. The strong correlation (r 2 = 0.77) of Al2O3 and TiO2 suggests that the source materials for this deposit are comparatively uniform. A number of heavy metal elements and trace elements occur. Cr, V, Ni, Cu are interpreted to be in phosphate minerals, largely apatite. Sr and Pb are interpreted to be in both phyllosilicates and phosphate minerals. Two populations of apatite were observed in the clay-sized fraction, one that was Fe and Si- bearing and another that was only Si-bearing. Fe-bearing apatite had Fe2O3 contents that varied from 0.38 to 5.32 wt% and SiO2 contents that varied from 0.90 to 3.32 wt%. The other apatite population had a wider range of SiO2 contents that varied from 0.77 to 8.80 wt%. TEM imaging shows that apatite grains are dominantly single crystals with lesser amounts of aggregates. Wavellite commonly occurs as individual or clusters of lath-like crystals and the chemical composition differs from the pure aluminium phosphate end member with average concentrations of components being that of CaO (1.57 wt%), Fe2O3 (1.98 wt%), SiO2 (5.94 wt%). In the clay-sized phosphate minerals investigated no fluorine was found above detection limit (approximately 0.15 wt%), nor was any uranium, radium, heavy metal, or REE element detected. The phyllosilicate mineralogy of the deposit is dominated by smectite (montmorillonite with lesser amounts of nontronite), palygorskite, illite and kaolinite. No systematic variation in the relative proportions of phyllosilicates was observed in the clay deposit. Energy dispersive spectroscopy EDS analysis indicates that chemical compositions of phyllosilicates are somewhat typical but overall are enriched with respect to Fe compared to theoretical end members. The relative enrichment of Fe is interpreted to be a primary sedimentary feature. Ca content in smectite minerals is high and may inhibit stabilization using lime or similar methods. The high percentages of montmorillonite and palygorskite explain the high bulk water contents observed. This investigation provides fundamentally new details regarding clay tailing deposits from closed phosphate mines in central Florida which can be used in restoration and reclamation efforts.  相似文献   
34.
Atmospheric mercury (Hg) is delivered to ecosystems via rain, snow, cloud/fog, and dry deposition. The importance of snow, especially snow that has passed through the forest canopy (throughfall), in delivering Hg to terrestrial ecosystems has received little attention in the literature. The snowpack is a dynamic system that links atmospheric deposition and ecosystem cycling through deposition and emission of deposited Hg. To examine the magnitude of Hg delivery via snowfall, and to illuminate processes affecting Hg flux to catchments during winter (cold season), Hg in snow in no-canopy areas and under forest canopies measured with four collection methods were compared: (1) Hg in wet precipitation as measured by the Mercury Deposition Network (MDN) for the site in Acadia National Park, Maine, USA, (2) event throughfall (collected after snowfall cessation for accumulations of >8 cm), (3) season-long throughfall collected using the same apparatus for event sampling but deployed for the entire cold season, and (4) snowpack sampling. Estimates (mean ± SE) of Hg deposition using these methods during the 91-day cold season in 2004–2005 at conifer sites showed that season-long throughfall Hg flux (1.80 μg/m2) < snowpack Hg (2.38 ± 0.68 μg/m2) < event throughfall flux (5.63 ± 0.38 μg/m2). Mercury deposition at the MDN site (0.91 μg/m2) was similar to that measured at other no-canopy sites in the area using the other methods, but was 3.4 times less than was measured under conifer canopies using the event sampling regime. This indicates that snow accumulated under the forest canopy received Hg from the overstory or exhibited less re-emission of Hg deposited in snow relative to open areas. The soil surface of field-scale plots were sprayed with a natural rain water sample that contained an Hg tracer (202Hg) just prior to the first snowfall to explore whether some snowpack Hg might be explained from soil emissions. The appearance of the 202Hg tracer in the snowpack (0–64% of the total Hg mass in the snowpack) suggests that movement of Hg from the soil into the snowpack is possible. However, as with any tracer study the 202Hg tracer may not precisely represent the reactivity and mobility of natural Hg in soils.  相似文献   
35.
Climate change is one of the most compelling challenges for science communication today. Societal reforms are necessary to reduce the risks posed by a changing climate, yet many people fail to recognize climate change as a serious issue. Unfortunately, the accumulation of scientific data, in itself, has failed to compel the general public on the urgent need for pro-environmental policy action. We argue that certain metaphors for the human-environment relationship can lead people to adopt a more nuanced and responsible conception of their place in the natural world. In two studies, we tested properties of multiple metaphors with the general public (study 1) and experts on climate change (study 2). The metaphor “the earth is our home” resonated with climate experts as well as diverse subpopulations of the general public, including conservatives and climate-change deniers.  相似文献   
36.
Gravity-flow sediments from the South Virgin Islands Trough Escarpment (west of the island of St. Croix) contain Late Cretaceous through Late Miocene nannofossils that are well mixed even within individual samples. These sediments, reworked and redeposited in latest Miocene or Early Pliocene, apparently occur within a sequence of Late Miocene-to-recent fan deposits. Marine source beds representing all pre-Pliocene epochs of the Cenozoic and latest Cretaceous must have been exposed along the NW-facing West St. Croix Escarpment. Southward tilting of the St. Croix Ridge has subsequently altered the depositional pattern.  相似文献   
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This article proposes a shift toward the integrated governance of watersheds as a basis for fostering health, sustainability and social–ecological resilience. The authors suggest that integrated watershed governance is more likely when different perspectives, including health and well-being, are explicitly understood, communicated, and sought as co-benefits of watershed management. A new conceptual device – the watershed governance prism – is introduced in relation to the multiple facets of governance that characterize contemporary water resources management and examined as an integrative framework to link social and environmental concerns with the determinants of health in the watershed context. The authors assess the diagnostic and communicative potential of such a framework, discussing its utility as a concise depiction of multiple, interacting policy priorities and as a guide to integrate different research and policy domains into the governance of water, health and social–ecological systems.  相似文献   
39.
We examine the potential for diurnal variation in elevation of saltmarsh surfaces as a source of error in long-term experiments; errors particularly critical in high precision studies that employ the surface elevation table (SET) as a means to monitor elevations. The field study was carried out along the New Brunswick coast of the Bay of Fundy in high and low zones at three marshes with different tidal ranges. We used a total of 16 benchmark pipes and controlled for daily variability in evapotranspiration (ET), as well as timing of tidal flooding, two factors that affect soil water storage, and consequently soil volumes. In six of nine trials we detected significant elevation change over periods as short as 5 d. Marsh-wide averages ranged from 1.2 to 3.0 mm, greater than the yearly increase in relative sea level in many regions. Wood Point marsh had the highest tidal range, but lowest soil organic matter content, giving its soils the lowest compressibility and little sensitivity to ET during two of three trials; the average change in elevation in Wood Point high marsh stations was 4.0 mm during the last trial. Greater differences later in the growing season (while temperature changes were minor) at Wood Point and another site suggest that plant transpiration drove changes in water storage at those sites. Significantly greater differences in elevation with lower plant cover in the third marsh suggests that evaporation drove changes in water storage there. Surface elevation change due to ET should be of greatest concern to SET users in temperate regions where there are large changes in plant biomass and variable temperatures. Variation due to plant transpiration could be reduced if yearly monitoring is scheduled before the start of the growing season.  相似文献   
40.
Compositional heterogeneity (56–64 wt% SiO2 whole-rock) in samples of tephra and lava from the 1986 eruption of Augustine Volcano, Alaska, raises questions about the physical nature of magma storage and interaction beneath this young and frequently active volcano. To determine conditions of magma storage and evolutionary histories of compositionally distinct magmas, we investigate physical and chemical characteristics of andesitic and dacitic magmas feeding the 1986 eruption. We calculate equilibrium temperatures and oxygen fugacities from Fe-Ti oxide compositions and find a continuous range in temperature from 877 to 947°C and high oxygen fugacities (ΔNNO=1–2) for all magmas. Melt inclusions in pyroxene phenocrysts analyzed by Fourier-transform infrared spectroscopy and electron probe microanalysis are dacitic to rhyolitic and have water contents ranging from <1 to ∼7 wt%. Matrix glass compositions are rhyolitic and remarkably similar (∼75.9–76.6 wt% SiO2) in all samples. All samples have ∼25% phenocrysts, but lower-silica samples have much higher microlite contents than higher-silica samples. Continuous ranges in temperature and whole-rock composition, as well as linear trends in Harker diagrams and disequilibrium mineral textures, indicate that the 1986 magmas are the product of mixing between dacitic magma and a hotter, more mafic magma. The dacitic endmember is probably residual magma from the previous (1976) eruption of Augustine, and we interpret the mafic endmember to have been intruded from depth. Mixing appears to have continued as magmas ascended towards the vent. We suggest that the physical structure of the magma storage system beneath Augustine contributed to the sustained compositional heterogeneity of this eruption, which is best explained by magma storage and interaction in a vertically extensive system of interconnected dikes rather than a single coherent magma chamber and/or conduit. The typically short repose period (∼10 years) between Augustine's recent eruptive pulses may also inhibit homogenization, as short repose periods and chemically heterogeneous magmas are observed at several volcanoes in the Cook Inlet region of Alaska.  相似文献   
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