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Fiona Simpson 《GeoJournal》2000,50(2-3):127-131
Ethnic minorities are facing increasing problems of social exclusion in Central and Eastern Europe. The complex nature of the transition from socialism means that the institutional framework to support them is still being established. Whilst non-governmental organisations (NGOs) have a crucial role to play in promoting a more inclusive society, through improving access to local democratic structures for otherwise excluded groups and acting as fora for improved community participation throughout the region, their development remains fraught with problems. Examination of the experiences of one such organisation, ETNO Agentura based in northern Slovakia, provides an insight into the problems and opportunities arising as community representatives work together to provide social support for ethnic minorities. The paper outlines key issues arising from the case of ETNO Agentura, including difficulty in gaining access to supporting finance and securing long term financial viability, the lack of institutional capacity of local authorities to become receptive to their views, and implicit socio-cultural barriers to ethnic minority representation in community participation processes. Developing a fuller understanding of these problems and the measures required to overcome them is a central part of establishing a more effective role for NGOs within post socialist societies. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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The White method, routinely used to estimate phreatophyte transpiration from diel groundwater variation, also provides measures of total evapotranspiration (ET) and groundwater fluxes in surface waters. Such applications remain rare, however, and critically require accurate representation of stage‐dependent variation in specific yield (Sy). High‐resolution stage data from three Florida swamps were used to evaluate different relationships between Sy and stage (ecosystem specific yield, ESY). A discretized form, ESYD, assumes constant Sy near unity for inundated conditions, applying soil Sy for belowground stage and open water Sy (Sy,OW ≈ 1.0) for aboveground stage. A mixture approach, ESYM, applies a stage‐dependent interpolation between Sy,Soil and Sy,OW using stage‐area relationships and assumes rapid lateral equilibration between inundated and non‐inundated wetland areas. Finally, an empirical formulation, ESYRR, uses measured ratios of rain to rise to estimate stage‐specific Sy. All formulations yielded reasonable ET rates (ET ≈ PET) at high stage; ESYD markedly overestimated ET (ET/PET > 3) at intermediate stage, whereas ESYM and ESYRR maintained ET/PET near 1.0. Estimated groundwater fluxes using ESYM and ESYRR correlated well with Darcy‐estimated flows, but were larger, likely due to uncertainties in Darcy parameters. Well transects across wetlands documented equal water elevation and diel variation across inundated and non‐inundated areas, verifying rapid equilibration that reduces Sy and explaining overestimation by ESYD. However, equilibration area varied within and among wetlands, explaining observed differences between ESYM and ESYRR, and suggesting ESYRR may be preferred. Stage histograms followed the shape of ESYRR, highlighting reciprocal influences of ESY on stage stability. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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New articulated specimens of the British Ordovician cystoid first mentioned under the name ‘Hemicosmites rugatus Forbes’ in 1848 allow its morphology and systematic affinities to be established for the first time. Despite being based on isolated plates, ‘H. rugatus Forbes’ has been reported from England and Wales, Belgium, France, Spain and Thailand, and has been attributed to four genera. It is characterized by a heteromorphic, circular stem, a theca with four basal, six infra‐lateral and eight lateral plates, all with sharp‐crested ridges running to plate angles, multiple arms in each ambulacrum and an extensive tegmen. These characters indicate it belongs in the family Caryocrinitidae and genus Caryocrinites. Caryocrinites rugatus had arms with lateral brachioles that folded in against the main arm axis, as in the type species C. ornatus Say. It is the first Ordovician species known to possess this character. Isolated plates show sorting and a few may represent other species of Caryocrinites s.l. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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The aim of this study was to determine the extent Nephrops consumes plastics in the Clyde Sea and if this intake occurs through their diet. Plastic contamination was found to be high in Nephrops, 83% of the animals sampled contained plastics (predominately filaments) in their stomachs. Tightly tangled balls of plastic strands were found in 62% of the animals studied but were least prevalent in animals which had recently moulted. No significant difference in plastic load was observed between males and females. Raman spectroscopy indicated that some of the microfilaments identified from gut contents could be sourced to fishing waste. Nephrops fed fish seeded with strands of polypropylene rope were found to ingest but not to excrete the strands. The fishery for Norway lobster, Nephrops norvegicus, is the most valuable in Scotland and the high prevalence of plastics in Nephrops may have implications for the health of the stock.  相似文献   
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Previous discussions of the catastrophic drainage of ice-dammed lakes have centred on mechanisms where characteristics of the lake are crucial to drainage initiation, for example dam flotation or tunnel formation at a critical lake depth. This paper describes a mechanism for lake drainage where drainage initiation depends on the characteristics of the glacier and is independent of the characteristics of the lake. Prediction of this mechanism must be based on glacier dynamics, whereas the mechanisms most commonly discussed previously are best predicted primarily on the basis of lake evolution. An ice-dammed lake at the margin of the glacier Solheimajokull, in southern Iceland, was observed to drain rapidly into the sub- or englacial drainage system, supplying water and debris to the bed or interior of the glacier. Geomorphological evidence suggests that the lake drains and refills periodically, discharging up to 13300 m3 of water into the glacier-hydrological system. The depth of the maximum lake is insufficient to cause either flotation of the ice margin or tunnel opening by plastic deformation of the ice, and we suggest that sudden drainage is related to ice-bed separations associated with specific glacier flow states rather than to a critical lake depth threshold. This mechanism of lake drainage has implications for conditions at the glacier bed, for the development of basal ice and for the entrainment of debris into the glacier, as well as for the prediction of potentially hazardous catastrophic drainage events and jokulhlaups from ice-dammed lakes.  相似文献   
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In northwestern California, the Franciscan subduction complex has been subdivided into seven major tectonostratigraphic units. We report U-Pb ages of ≈2400 detrital zircon grains from 26 sandstone samples from 5 of these units. Here, we tabulate each unit’s interpreted predominant sediment source areas and depositional age range, ordered from the oldest to the youngest unit. (1) Yolla Bolly terrane: nearby Sierra Nevada batholith (SNB); ca. 118 to 98 Ma. Rare fossils had indicated that this unit was mostly 151–137 Ma, but it is mostly much younger. (2) Central Belt: SNB; ca. 103 to 53 Ma (but poorly constrained), again mostly younger than previously thought. (3) Yager terrane: distant Idaho batholith (IB); ca. 52 to 50 Ma. Much of the Yager’s detritus was shed during major core complex extension and erosion in Idaho that started 53 Ma. An Eocene Princeton River–Princeton submarine canyon system transported this detritus to the Great Valley forearc basin and thence to the Franciscan trench. (4) Coastal terrane: mostly IB, ±SNB, ±nearby Cascade arc, ±Nevada Cenozoic ignimbrite belt; 52 to <32 Ma. (5) King Range terrane: dominated by IB and SNB zircons; parts 16–14 Ma based on microfossils. Overall, some Franciscan units are younger than previously thought, making them more compatible with models for the growth of subduction complexes by progressive accretion. From ca. 118 to 70 Ma, Franciscan sediments were sourced mainly from the nearby Sierra Nevada region and were isolated from southwestern US and Mexican sources. From 53 to 49 Ma, the Franciscan was sourced from both Idaho and the Sierra Nevada. By 37–32 Ma, input from Idaho had ceased. The influx from Idaho probably reflects major tectonism in Idaho, Oregon, and Washington, plus development of a through-going Princeton River to California, rather than radical changes in the subduction system at the Franciscan trench itself.  相似文献   
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