995 resultados para between Baffin and Bylot Island
Resumo:
The Mediterranean is regarded as a region of intense climate change. To better understand future climate change, this area has been the target of several palaeoclimate studies which also studied stable isotope proxies that are directly linked to the stable isotope composition of water, such as tree rings, tooth enamel or speleothems. For such work, it is also essential to establish an isotope hydrology framework of the region of interest. Surface waters from streams and lakes as well as groundwater from springs on the island of Corsica were sampled between 2003 and 2009 for their oxygen and hydrogen isotope compositions. Isotope values from lake waters were enriched in heavier isotopes and define a local evaporation line (LEL). On the other hand, stream and spring waters reflect the isotope composition of local precipitation in the catchment. The intersection of the LEL and the linear fit of the spring and stream waters reflect the mean isotope composition of the annual precipitation (dP) with values of -8.6(±0.2) per mil for d18O and -58(±2) per mil for d2H. This value is also a good indicator of the average isotope composition of the local groundwater in the island. Surface water samples reflect the altitude isotope effect with a value of -0.17(±0.02) per mil per 100 m elevation for oxygen isotopes. At Vizzavona Pass in central Corsica, water samples from two catchments within a lateral distance of only a few hundred metres showed unexpected but systematic differences in their stable isotope composition. At this specific location, the direction of exposure seems to be an important factor. The differences were likely caused by isotopic enrichment during recharge in warm weather conditions in south-exposed valley flanks compared to the opposite, north-exposed valley flanks.
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Regional autonomy in Indonesia was initially introduced as a means of pacifying regional disappointment at the central government. Not only did the Regional Autonomy Law of 1999 give the Balinese a chance to express grievance regarding the centralist policies of the Jakarta government but also provided an opportunity to return to the regional, exclusive, traditional village governance (desa adat). As a result, the problems faced by the island, particularly ethnic conflicts, are increasingly handled by the mechanism of this traditional type of governance. Traditional village governance with regard to ethnic conflicts (occurring) between Balinese and migrants has never been systematically analyzed. Existing analyses emphasized only the social context, but do not explain either the cause of conflicts and the ensuing problems entails or the virtues of traditional village governance mechanisms for mediating in the conflict. While some accounts provide snapshots, they lack both theoretical and conflict study perspective. The primary aim of this dissertation is to explore the expression and the causes of conflict between the Balinese and migrants and to advance the potential of traditional village governance as a means of conflict resolution with particular reference to the municipality of Denpasar. One conclusion of the study is that the conflict between the Balinese and migrants has been expressed on the level of situation/contradiction, attitudes, and behavior. Yet the driving forces behind the conflict itself consist of the following factors: absence of cooperation; incompatible position and perception; inability to communicate effectively; and problem of inequality and injustice, which comes to the surface as a social, cultural, and economic problem. This complex of factors fuels collective fear for the future of both groups. The study concludes that traditional village governance mechanisms as a means of conflict resolution have not yet been able to provide an enduring resolution for the conflict. Analysis shows that the practice of traditional village governance is unable to provide satisfactory mechanisms for the conflict as prescribed by conflict resolution theory. Traditional village governance, which is derived from the exclusive Hindu-Balinese culture, is accepted as more legitimate among the Balinese than the official governance policies. However, it is not generally accepted by most of the Muslim migrants. In addition, traditional village governance lacks access to economic instruments, which weakens its capacity to tackle the economic roots of the conflict. Thus the traditional mechanisms of migrant ordinance , as practiced by the traditional village governance have not yet been successful in penetrating all aspects of the conflict. Finally, one of the main challenges for traditional village governance s legal development is the creation of a regional legal system capable of accommodating rapid changes in line with the national and international legal practices. The framing of the new laws should be responsive to the aspirations of a changing society. It should not only protect the various Balinese communities interests, but also that of other ethnic groups, especially those of the minority. In other words, the main challenge to traditional village governance is its ability to develop flexibility and inclusiveness.
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The elemental composition of otoliths may provide valuable information for establishing connectivity between fish nursery grounds and adult fish populations. Concentrations of Rb, Mg, Ca, Mn, Sr, Na, K, Sr, Pb, and Ba were determined by using solution-based inductively coupled plasma mass spectrometry in otoliths of young-of-the year tautog (Tautoga onitis) captured in nursery areas along the Rhode Island coast during two consecutive years. Stable oxygen (δ18O) and carbon (δ13C) isotopic ratios in young-of-the year otoliths were also analyzed with isotope ratio mass spectrometry. Chemical signatures differed significantly among the distinct nurseries within Narragansett Bay and the coastal ponds across years. Significant differences were also observed within nurseries from year to year. Classification accuracy to each of the five tautog nursery areas ranged from 85% to 92% across years. Because accurate classification of juvenile tautog nursery sites was achieved, otolith chemistry can potentially be used as a natural habitat tag.
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House Finches (CarpQdacqs mexiCAnuS) were introduced to Long Island, New York from southern'California in 1940. Apparently, an initial sample of less than 100 birds has given rise to a population that now occupies much of the eastern United States. This study was to determine if morphological and reproductive changes have taken place in introduced eastern birds, which have colonized a novel environment. A study area in Goleta, California (CAL) represented the parental population whereas for comparison, House Finches in St. Catharines, Ontario (ONT) represented the introduced population. Interlocality variation in 25 morphometric characters of 100 adult House Finches was examined statistically. Singleclassification analysis of variance revealed significant interlocality differentiation in seven characters of males and nine of females. Females showed differentiation in more limb elements than males. Analysis of character variation using discriminant and principal component analysis distinguished samples on the basis of variation in shape. Compared to CAL, aNT birds (especially females) had smaller extremities relative to certain core parts and weight. Females showed similar patterns of character covariation in each locality on the second principal component, which suggests that differentiation of the ONT population may not be solely environmentally induced. Sexual dimorphism was evident in four charaoters in aNT and five in CAL. Disoriminant analysis distinguished sex on the basis of variation in shape. Males possessed a relatively larger flying apparatus and small.er hind limbs than females. The dearee of sexual dimorphism did not vary sicnifioantly between looalities. 3 Data on reproduotive parameters were oolleoted in 1983 and 1984 in ONT, and 1984 in CAL. In 1984, Bouse Finohes began breedina approximately three months earlier in CAL than in ONT. In ONT, there was no sianifioant differenoe in mean olutoh initiation date between 1983 and 1984. In both looalities most nests oontained either four or five ea",s, and olutoh size differenoes between looalites were not signifioant. Seasonal deolines in olutch size were evident in ONT but not in CAL. Intralooality variation in e.g weight and size was not related to clutch size. E",g weiaht showed no seasonal trend in ONT, but inoreased sianifioantly with breed ina season in OAL. In both looalities e8'''' weiaht increased sipifioantly with order of layina in olutohes of four but not in clutohes of five. Eag's in ONT in 1983 and 1984 were sip.ificantly larser than in CAL in 1984. The modal inoubation period was 13 days and did not vary sip.ifioantly between localites. In both looalities nestling weiaht on the day of hatohing was oorrelated to fresh ega welaht. For muoh of the period between hatohing and 14 days post-hatoh, ONT nestlinas were signifioantly laraer than CAL nestlings in terms of weiaht. bill length, bill depth, and manus length.
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À l’origine, la nouvelle concernant l’occupation américaine d’Haïti en 1915 a suscité peu d’indignation aux États-Unis. En effet, on reproche à la république son instabilité politique et on juge aussi qu’une intervention américaine concourrait à l’édifice de l’autorité de la loi. À partir de 1915 et surtout en 1920, l’Association nationale pour l’avancement des gens de couleur (NAACP), fondée en 1909, critique cette ingérence et milite pour y voir un terme. W.E. B. Du Bois et James Weldon Johnson, deux figures publiques noires importantes travaillant au sein de l’organisation, dénoncent avec conviction l’occupation d’Haïti. Les historiens ont jusqu’ici jugé que la NAACP fut inspirée par des considérations de solidarité raciale en adhérant à la cause de la souveraineté haïtienne. Si la thèse présente ne réfute pas cette possibilité, elle cherche tout de même à démontrer que le cadre conceptuel de la solidarité raciale ne saurait illustrer toute la complexité de la campagne haïtienne érigée par la NAACP. Par conséquent, une attention dirigée davantage sur le contexte social et politique américain entre 1915 et 1922 révèle que pour la NAACP, la dénonciation de l’occupation américaine d’Haïti représentait d’une part une opportunité de discuter des problèmes sociaux touchant les Afro-Américains, et d’autre part, une occasion de renforcer sa position aux États-Unis.
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Studies of code-switching in writing are very limited in comparison with the numerous investigations of this phenomenon in oral communication. Recent research has revealed that in text-based computer-mediated communication internet users bring into play the various languages available in their linguistic repertoire and, consequently, switch between them. In this case study, I investigate digital code-switching between Cypriot and Standard Greek, the two varieties of Greek spoken on the island of Cyprus. Following Auer’s conversation analytic approach and Gafaranga’s view that conversational structure coexists with social structure, I investigate code-switching in online interactions. The data to be analysed here, unlike those considered in most studies of code-switching, are written data, obtained from channel #Cyprus of Internet Relay Chat. The results suggest that code-switching in writing is influenced not only by macro-sociolinguistic factors, but they are also shaped by the medium- and social-specific characteristics of Internet Relay Chat. This, in turn, allows internet users to gain access to different roles and perform various identities within this online context.
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Correct estimation of the firn lock-in depth is essential for correctly linking gas and ice chronologies in ice core studies. Here, two approaches to constrain the firn depth evolution in Antarctica are presented over the last deglaciation: outputs of a firn densification model, and measurements of δ15N of N2 in air trapped in ice core, assuming that δ15N is only affected by gravitational fractionation in the firn column. Since the firn densification process is largely governed by surface temperature and accumulation rate, we have investigated four ice cores drilled in coastal (Berkner Island, BI, and James Ross Island, JRI) and semi-coastal (TALDICE and EPICA Dronning Maud Land, EDML) Antarctic regions. Combined with available ice core air-δ15N measurements from the EPICA Dome C (EDC) site, the studied regions encompass a large range of surface accumulation rates and temperature conditions. Our δ15N profiles reveal a heterogeneous response of the firn structure to glacial–interglacial climatic changes. While firn densification simulations correctly predict TALDICE δ15N variations, they systematically fail to capture the large millennial-scale δ15N variations measured at BI and the δ15N glacial levels measured at JRI and EDML – a mismatch previously reported for central East Antarctic ice cores. New constraints of the EDML gas–ice depth offset during the Laschamp event (~41 ka) and the last deglaciation do not favour the hypothesis of a large convective zone within the firn as the explanation of the glacial firn model–δ15N data mismatch for this site. While we could not conduct an in-depth study of the influence of impurities in snow for firnification from the existing datasets, our detailed comparison between the δ15N profiles and firn model simulations under different temperature and accumulation rate scenarios suggests that the role of accumulation rate may have been underestimated in the current description of firnification models.
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Globalization has resulted in unprecedented movements of people, goods, and alien species across the planet. Although the impacts of biological invasions are widely appreciated, a bias exists in research effort to post-dispersal processes because of the difficulties of measuring propagule pressure. The Antarctic provides an ideal model system in which to investigate propagule movements because of the region's isolation and small number of entry routes. Here we investigated the logistics operations of the South African National Antarctic Programme (SANAP) and quantified the initial dispersal of alien species into the region. we found that over 1400 seeds from 99 taxa are transported into the Antarctic each field season in association with SANAP passenger luggage and cargo. The first ever assessment of propagule drop-off indicated that 30-50% of these propagules will enter the recipient environment. Many of the taxa include cosmopolitan weeds and known aliens in the Antarctic, indicating that logistics operations form part of a globally self-perpetuating cycle moving alien species between areas of human disturbance. in addition, propagules of some taxa native to the Antarctic region were also found, suggesting that human movements may be facilitating intra-regional homogenization. Several relatively simple changes in biosecurity policy that could significantly reduce the threat of introduction of nonnative species are suggested.
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During the international "Overflow-Expedition'' 1973 on R.V. "Meteor" oxygen concentrations in surface layers were measured in order to determine the oxygen gradients within the first two meters and to add some informations to the mechanisms of oxygen exchange at the air-sea interface. These investigations may be interesting also with regard to longterm- observations of the oxygen distribution in the Atlantic, especially the problem of the A.O.U. (apparent oxygen utilization) determination. To measure oxygen gradients a special sampler was built which is able to take water samples each 20 cm of the first 2 meters. These data were supplemented by further samples down to 150 m, taken by conventional water samplers, from which samples were also taken to measure N2/O2-relations. By comparing these relations with theoretical relations in air-saturated water the influence of biological production and consumption on the oxygen contents in water could be estimated. A simple glass apparatus was built to extract gas from the water samples, and hereafter the N2/O2-relations were determined by mass spectrometry. Most distributions of the oxygen anomaly show a negative oxygen balance which varies largely, probably due to strong mixing processes in the Iceland-Faroe ridge area. The distribution of surface oxygen saturation values are of two different types. The values of the stations 260, 262 and 270 stem from mixed water and show homogeneous supersaturations, as can be found instantly when whitecaps appear. The values of 9 other stations are from water, sampled during calm periods which has been mixed and supersaturated before. They show a decreasing oxygen saturation towards the sea surface and often undersaturation in the upper decimeters up to 98 % and even 91 %. So at the air-sea interface even less initial oxygen saturation than 100 % can be found after supersaturation during heavy weather periods.
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Seasonal patterns in hydrography, partial pressure of CO2, fCO2, pHt, total alkalinity, AT, total dissolved inorganic carbon, CT, nutrients, and chlorophyll a were measured in surface waters on monthly cruises at the European Station for Time Series in the Ocean at the Canary Islands (ESTOC) located in the northeast Atlantic subtropical gyre. With over 5 years of oceanographic data starting in 1996, seasonal and interannual trends of CO2 species and air-sea exchange of CO2 were determined. Net CO2 fluxes show this area acts as a minor source of CO2, with an average outgassing value of 179 mmol CO2/m**2 yr controlled by the dominant trade winds blowing from May to August. The effect of short-term wind variability on the CO2 flux has been addressed by increasing air-sea fluxes by 63% for 6-hourly sampling frequency. The processes governing the monthly variations of CT have been determined. From March to October, when CT decreases, mixing at the base of the mixed layer (11.5 ± 1.5 mmol/m**3) is compensated by air-sea exchange, and a net organic production of 25.5 ± 5.7 mmol/m**3 is estimated. On an annual scale, biological drawdown accounts for the decrease in inorganic carbon from March to October, while mixing processes control the CT increase from October to the end of autumn. After removing seasonality variability, fCO2sw increases at a rate of 0.71 ± 5.1 µatm/yr, and as a response to the atmospheric trend, inorganic carbon increases at a rate of 0.39 ± 1.6 µmol/kg yr.
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The Advanced Land Observation System (ALOS) Phased-Array Synthetic-Aperture Radar (PALSAR) is an L-band frequency (1.27 GHz) radar capable of continental-scale interferometric observations of ice sheet motion. Here, we show that PALSAR data yield excellent measurements of ice motion compared to C-band (5.6 GHz) radar data because of greater temporal coherence over snow and firn. We compare PALSAR velocities from year 2006 in Pine Island Bay, West Antarctica with those spanning years 1974 to 2007. Between 1996 and 2007, Pine Island Glacier sped up 42% and ungrounded over most of its ice plain. Smith Glacier accelerated 83% and ungrounded as well. Their largest speed up are recorded in 2007. Thwaites Glacier is not accelerating but widening with time and its eastern ice shelf doubled its speed. Total ice discharge from these glaciers increased 30% in 12 yr and the net mass loss increased 170% from 39 ± 15 Gt/yr to 105 ± 27 Gt/yr. Longer-term velocity changes suggest only a moderate loss in the 1970s. As the glaciers unground into the deeper, smoother beds inland, the mass loss from this region will grow considerably larger in years to come.