971 resultados para Landscape changes -- Catalonia -- Girona (Province) -- 20th century


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Long term management plans for restoration of natural flow conditions through the Everglades increase the importance of understanding potential nutrient impacts of increased freshwater delivery on coastal biogeochemistry. The present study sought to increase understanding of the coastal marine system of South Florida under modern conditions and through the anthropogenic changes in the last century, on scales ranging from individual nutrient cycle processes to seasonal patterns in organic material (OM) under varying hydrodynamic regime, to century scale analysis of sedimentary records. In all applications, carbon and nitrogen stable isotopic compositions of OM were examined as natural recorders of change and nutrient cycling in the coastal system. High spatial and temporal variability in stable isotopic compositions were observed on all time scales. During a transient phytoplankton bloom, ä15N values suggested nitrogen fixation as a nutrient source supporting enhanced productivity. Seasonally, particulate organic material (POM) from ten sites along the Florida Reef Tract and in Florida Bay demonstrated variable fluctuations dependent on hydrodynamic setting. Three separate intra-annual patterns were observed, yet statistical differences were observed between groupings of Florida Bay and Atlantic Ocean sites. The POM ä15N values ranged on a quarterly basis by 7‰, while ä13C varied by 22‰. From a sediment history perspective, four cores collected from Florida Bay further demonstrated the spatial and temporal variability of the system in isotopic composition of bulk OM over time. Source inputs of OM varied with location, with terrestrial inputs dominating proximal to Everglades freshwater discharge, seagrasses dominating in open estuary cores, and a marine mixture of phytoplankton and seagrass in a core from the boundary zone between Florida Bay and the Gulf of Mexico. Significant shifts in OM geochemistry were observed coincident with anthropogenic events of the 20th century, including railroad and road construction in the Florida Keys and Everglades, and also the extensive drainage changes in Everglades hydrology. The sediment record also preserved evidence of the major hurricanes of the last century, with excursions in geochemical composition coincident with Category 4-5 storms.

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Lead isotopic compositions and Pb and Ba concentrations have been measured in ice cores from Law Dome, East Antarctica, covering the past 6500 years. 'Natural' background concentrations of Pb (ab. 0.4 pg/g) and Ba (ab. 1.3 pg/g) are observed until 1884 AD, after which increased Pb concentrations and lowered 206Pb/207Pb ratios indicate the influence of anthropogenic Pb. The isotopic composition of 'natural' Pb varies within the range 206Pb/207Pb=1.20-1.25 and 208Pb/207Pb=2.46-2.50, with an average rock and soil dust Pb contribution of 8-12%. A major pollution event is observed at Law Dome between 1884 and 1908 AD, elevating the Pb concentration four-fold and changing 206Pb/207Pb ratios in the ice to ab. 1.12. Based on Pb isotopic systematics and Pb emission statistics, this is attributed to Pb mined at Broken Hill and smelted at Broken Hill and Port Pirie, Australia. Anthropogenic Pb inputs are at their greatest from 1900 to 1910 and from ab. 1960 to ab. 1980. During the 20th century, Ba concentrations are consistently higher than 'natural' levels and are attributed to increased dust production, suggesting the influence of climate change and/or changes in land coverage with vegetation.

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Background: Conifer populations appear disproportionately threatened by global change. Most examples are, however, drawn from the northern hemisphere and long-term rates of population decline are not well documented as historical data are often lacking. We use a large and long-term (1931-2013) repeat photography dataset together with environmental data and fire records to account for the decline of the critically endangered Widdringtonia cedarbergensis. Eighty-seven historical and repeat photo-pairs were analysed to establish 20th century changes in W. cedarbergensis demography. A generalized linear mixed-effects model was fitted to determine the relative importance of environmental factors and fire-return interval on mortality for the species. Results: From an initial total of 1313 live trees in historical photographs, 74% had died and only 44 (3.4%) had recruited in the repeat photographs, leaving 387 live individuals. Juveniles (mature adults) had decreased (increased) from 27% (73%) to 8% (92%) over the intervening period. Our model demonstrates that mortality is related to greater fire frequency, higher temperatures, lower elevations, less rocky habitats and aspect (i.e. east-facing slopes had the least mortality). Conclusions: Our results show that W. cedarbergensis populations have declined significantly over the recorded period, with a pronounced decline in the last 30 years. Individuals that established in open habitats at lower, hotter elevations and experienced a greater fire frequency appear to be more vulnerable to mortality than individuals growing within protected, rocky environments at higher, cooler locations with less frequent fires. Climate models predict increasing temperatures for our study area (and likely increases in wildfires). If these predictions are realised, further declines in the species can be expected. Urgent management interventions, including seedling out-planting in fire-protected high elevation sites, reducing fire frequency in higher elevation populations, and assisted migration, should be considered.

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The Indian winter monsoon (IWM) is a key component of the seasonally changing monsoon system that affects the densely populated regions of South Asia. Cold winds originating in high northern latitudes provide a link of continental-scale Northern Hemisphere climate to the tropics. Western Disturbances (WD) associated with the IWM play a critical role for the climate and hydrology in northern India and the western Himalaya region. It is vital to understand the mechanisms and teleconnections that influence IWM variability to better predict changes in future climate. Here we present a study of regionally calibrated winter (January) temperatures and according IWM intensities, based on a planktic foraminiferal record with biennial (2.55 years) resolution. Over the last ~250 years, IWM intensities gradually weakened, based on the long-term trend of reconstructed January temperatures. Furthermore, the results indicate that IWM is connected on interannual- to decadal time scales to climate variability of the tropical and extratropical Pacific, via El Niño Southern Oscillation (ENSO) and Pacific Decadal Oscillation (PDO). However, our findings suggest that this relationship appeared to begin to decouple since the beginning of the 20th century. Cross-spectral analysis revealed that several distinct decadal-scale phases of colder climate and accordingly more intense winter monsoon centered at the years ~1800, ~1890 and ~1930 can be linked to changes of the North Atlantic Oscillation (NAO).

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The study of diatoms in core HC11 collected from the southwestern part of Chukchi Sea, allowed to distinguish 3 diatoms ecological zones, reflecting paleoenvironmental changes during the last 2300 years. The sediment age was based on the sedimentation rates, determined by 210Pb and radiocarbon dating of mollusk shells. The environmental changes of Chukchi Sea revealed by examination of diatoms correlates with global climate changes - the warming of the early and middle Subatlantic and cooling of the late Subatlantic (Little Ice Age). Warming early and middle Subatlantic in the Chukchi Sea was probably stronger than the warming of the late 20th century and was not accompanied by significant changes in sea level.

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Non-cognitive skills have caught the attention of current education policy writers in Canada. Within the last 10 years, almost every province has produced a document including the importance of supporting non-cognitive skills in K-12 students in the classroom. Although often called different names (such as learning skills, cross curricular competencies, and 20th Century Skills) and occasionally viewed through different lenses (such as emotional intelligence skills, character skills, and work habits), what unifies non-cognitive skills within the policy documents is the claim that students that are strong in these skills are more successful in academic achievement and are more successful in post-secondary endeavors. Though the interest from policy-makers and educators is clear, there are still many questions about non-cognitive skills that have yet to be answered. These include: What skills are the most important for teacher’s to support in the classroom? What are these skills’ exact contributions to student success? How can teachers best support these skills? Are there currently reliable and valid measures of these skills? These are very important questions worth answering if Canadian teachers are expected to support non-cognitive skills in their classrooms with an already burdened workload. As well, it can begin to untangle the plethora of research that exists within the non-cognitive realm. Without a critical look at the current literature, it is impossible to ensure that these policies are effective in Canadian classrooms, and to see an alignment between research and policy. Upon analysis of Canadian curriculum, five non-cognitive skills were found to be the most prevalent among many of the provinces: Self-Regulation, Collaboration, Initiative, Responsibility and Creativity. The available research literature was then examined to determine the utility of teaching these skills in the classroom (can students improve on these skills, do these skills impact other aspects of students’ lives, and are there methods to validly and reliably assess these skills). It was found that Self-Regulation and Initiative had the strongest basis for being implemented in the classroom. On the other hand, Creativity still requires a lot more justification in terms of its impact on students’ lives and ability to assess in the classroom.

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Este artículo analiza una dinámica de intervenciones de Estados Unidos en América Latina que no ha atraído suficientemente la atención de los historiadores. En los años treinta y cuarenta, cuando Europa se hundía en una nueva confrontación bélica, ciertos sectores del gobierno y del mundo empresarial norteamericano intentaron articular una nueva relación con los países del continente basada en una propuesta de multilateralismo que se había configurado dentro de la Sociedad de Naciones (SN). Estos estadounidenses intentaron establecer una dinámica de relaciones triangulares con los gobiernos latinoamericanos y los organismos técnicos de la SN. Gracias a ello, como se mostrará en este artículo para el caso del funcionamiento del Comité Fiscal de la Sociedad de Naciones, los latinoamericanos fueron capaces de influir en el tipo de políticas que debían emanar de esta relación triangular. La importancia de esta historia no es menor. La relación triangular entre Estados Unidos, América Latina y la SN sirvió de base para la reconstrucción de la gobernanza global liderada por los Estados Unidos tras la guerra.

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En el siguiente trabajo presentamos un estudio multidimensional sobre la conceptualización de los pueblos originarios que han constituido los medios de prensa escrita en Mendoza durante la primera década del siglo XX. Para llevarlo a cabo acudimos al Archivo de Hemeroteca de la Biblioteca General San Martín de la Ciudad de Mendoza, teniendo como referencia al Diario Los Andes, principal periódico de la provincia, creado en 1882 y vigente en la actualidad. El objetivo del estudio es la identificación de las distintas formas de construcción conceptual sobre los pueblos etnográficos del actual territorio argentino que difundió dicho diario, y del modo en que dichos artículos periodísticos jugaron un rol activo en relación con el proceso de construcción de alteridad sociocultural y la legitimación de las políticas etnocidas implementadas por las clases dominantes.

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Inspired both by debates about the origins of the modern ideology of race and also by controversy over the place of Ireland and the Irish in theories of empire in the early modern Atlantic world, Renaissance Humanism and Ethnicity before Race argues that ethnic discourse among the elite in early modern Ireland was grounded firmly in the Renaissance Humanism and Aristotelianism which dominated all the European universities before the Enlightenment. Irish and English, Catholic and Protestant, all employed theories of human society based on Aristotle’s Politics and the natural law of the medieval universities to construct or dismantle the categories of civility and barbarism. The elites operating in Ireland also shared common resources, taught in the universities, for arguing about the human body and its ability to transmit hereditary characteristics. Both in Ireland and elsewhere in Europe, these theories of human society and the human body underwent violent changes in the late seventeenth century under the impact of the early Enlightenment. These changes were vital to the development of race as we know it.

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Germany, Italy and Japan were engaged in China from the turn of the 20th century to WWII. However, they formed an anti-Chinese alliance only at the final stage of their presence there, when Japan assumed an undisputed role of leader in the region. Despite its alliance with the Axis powers, Japan never implemented racial laws against the Jews in China. All of them took part in the Boxer Upraising suppression and received as a consequence extraterritorial rights and concessions. Moreover, Japan won the war against China in 1895 and transformed itself from a tributary country of China into an imperialistic power. It took possession of Taiwan and in the 1930s established a puppet government in Manchuria.Germany followed different route obtaining as indemnity for the murders of two missionaries the control of the Shandong province, which was later expanded thanks to the anti-Boxer coalition's victory. However, Germany lost all possessions when China entered WWI. The issue of Shandong was finally resolved at the Conference for Disarmament hold in Washington in 1921-2. Japan failed to gain ex-Germany territories. Finally, Italy arrived in the Far East at the turn of the century but was not very interested in the oriental colonialism to the same extent it was interested in Africa. Tianjin was its only concession in China, and it took almost a decade before a subvention to arrive from the Italian government for its development.In the 1920s and 1930s Germany and Italy engaged in successful diplomatic, commercial and military relationships with China. In fact, both were considered China's partners thanks to their experts at the service of the Chinese government. On the other hand, Japan position was opposite to them, because of its plans of aggression towards China which was to be transformed into “the natural extension” of the mainland. In 1935 Italy declared war on Ethiopia and abandoned the seat at the League of Nations. China interpreted the Italian aggression as the endorsement of Japan's politics towards China in Manchuria, and the relations between the two countries were broken off. After that Italy supported Wang Jingwei's puppet government during the Japanese occupation of China. Germany followed the same path in 1937, when it was evident that the Japanese were playing the leading role in the region, and decided to ally with Wang Jingwei too. Both Italy and Germany decided also to recognise the Manzhuguo and established diplomatic relations, definitively turning their backs on the old Chinese ally.The Rome-Berlin-Tokyo Axis sealed the alliance among the three countries, and it confirmed Japan as the leading power in the region. Nevertheless Japan did not apply the racial law against the Jews in China.

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In the first decades of 20th century the just instituted Brazilian Republic faced the challenge to modernize the country. Considering that the progress was associated with the exhaustion of the forest reserves and with climatic changes, two big issues were seen as fundamental: To Fight the Droughts and To Defend the Forests; headed by professionals who were dedicated to these ideals. This research starts from the premise that these were the main challenges enforced by nature to the Brazilian development; the general objective was delimited in the search to understand the meaning and the conception of the natural world by this group of professionals who faced the shock between modernizing the country and conserving its natural resources. Aiming to contribute with the construction of the Brazilian environmental history and to bring historical elements to the debate about the environment in the country, the author concentrates his attention to the analyses, the discussions and the actions that preceded the regulation on the use of natural resources and the implementation of the environmental legislation in Brazil, occurred in 1934. The investigation uses as methodological basis the theoretical directions of environmental history, using sources of data still little explored and valued. In such way, it is taken as starting point some published papers about this subject during the period between 1889 and 1934 in two technical magazines the Revista Brazil Ferro-Carril and the Revista do Club de Engenharia. National engineering played a basic role in this process while arguing, projecting and constructing the development. The formulated proposals, after being divulged, had fomented the interchange with other professionals and had favored the advance of ambient questions in Brazil, in the sense to preserve natural resources, to construct more harmonic relations between the society and the nature and to equate the development with the environment preservation

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Introducción: Desde finales del pasado siglo XX, los observatorios vienen jugando un papel muy destacado entre las instituciones orientadas a la reforma mediática por cuanto suponen una vital herramienta para el análisis y fiscalización ciudadana de los medios. En este contexto, la investigación plantea una cartografía pionera de los observatorios de medios en España e intenta sistematizar su origen, evolución y sus principales características, entre otras: objetivos, promotores y ámbitos de especialización. Metodología: Partiendo de una extensa revisión documental, el estudio construye un censo de 28 observatorios que se analizan a partir de un protocolo de observación y una entrevista cualitativa a una decena de responsables de las distintas iniciativas. Resultados y conclusiones: Los resultados demuestran la existencia de un panorama heterogéneo de experiencias entre las que predominan las fiscalizadoras y promovidas por universidades. No obstante, los observatorios se caracterizan por su difícil sostenibilidad y por una actividad investigadora discontinua y poco constante.

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Nowadays language communication plays an important role in the world. For the technological explosion in the 20th century, the electronic mass media collapsed space and time barriers in human communication, enabling people to interact and live on a global scale. In this sense, the earth has been turned into a village by the electronic mass media. It not only changes the distance between countries, societies, but also shortens it between people. It means that the technological advancement makes the earth become a village. Since the distance between people is shortened, language communication becomes more important than before. To enhance language abilities, people can apply many different types of language learning strategies according to the learning styles that they have in order to learn the target language. In the Foreign Language Department of University of El Salvador Seminar students year 2006 apply different language learning strategies which make some of them get a grade either above eight or below it. To understand learning strategies, people can go back to basic term, strategy. This word comes from the ancient Greek term strategia meaning generalship or the art of war. A different, but related, word is tactics, which are tools to achieve the success of strategies. The two expressions share some basic implied characteristics: planning, competition, conscious manipulation, and movement toward a goal.

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Este artículo pretende mostrar algunos de los cambios sociales que se dieron en Medellín al finalizar el siglo XIX e iniciar XX, momento en el que la ciudad vivió un proceso de crecimiento urbano no experimentado antes y que provocó la progresiva adecuación de nuevos organismos e instituciones para suplir las demandas económicas y sociales que también se fueron incrementan­do. Organizar e higienizar el espacio urbano, acorde con las ideas de ciudad y de ciudadano que se estaban imple­mentando en Europa, fueron algunas de las metas que se establecieron para planear la ciudad y, a la vez, tratar de mitigar el impacto del crecimiento de­mográfico que acusaba problemáticas de tipo social. Casas de beneficencia, manicomios, orfelinatos, hospitales, cárceles, patronatos, teatros, universi­dades, entre otras, fueron algunas de aquellas alternativas que se idearon con el fin de prevenir estas problemá­ticas, así como también propendieron por moralizar, distraer y castigar los comportamientos que se calificaban de inadecuados por parte de las élites.

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La noria fluvial ha sido utilizada desde hace siglos en la provincia de Córdoba para elevar agua de los ríos y regar las huertas establecidas en sus inmediaciones. La mayoría de ellas estaba situada en los ríos Genil, Guadajoz y Guadalquivir, y muchas de esas norias se han mantenido en uso hasta el siglo XX. La primera parte del trabajo se dedica a reunir los diversos testimonios históricos que nos informan sobre el uso de las norias fluviales en Córdoba: lugares de emplazamiento, períodos de actividad, finalidad de uso. La segunda parte analiza los rasgos técnicos de las norias a través del estudio de dos modelos diferentes: la noria de piezas de madera, de tradición medieval, algunos de cuyos ejemplares se han conservado en lugares como Palma del Río y Castro del Río hasta los años setenta del presente siglo; y la noria con elementos de hierro fundido, de diseño más moderno, muy utilizada desde mediados del siglo XIX y de la que todavía se conserva algún ejemplar, como la situada en el curso del río Genil cerca de la aldea de Jauja (Lucena).