785 resultados para Missions -- Theory -- Korea (South) -- 21st century.


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Led to become a national productive Center, the Great Dourados Region, which consists of 40 cities located in the south of the state of Mato Grosso do Sul - Brazil, emerged as a grain productive region from the middle of the 1970s in the 20th century to the beginning of the 21st century. Using modern agricultural techniques, the land organization in this region was ruled by a development policy which was not concerned with the socio environmental aspects of the area. In this context, the present work aims to analyze the development process of the Great Dourados region, through soybean production and its relation to the confinement of the indigenous people present in the Area. This integration happened due to the money and for it, inserting this Region into a national productive pattern which guided the farmers to modern crops, mainly soybean. The land cultivation was not the only productive activity that granted the Region an economic integration, to both the national and international market. From the end of the Paraguay War (1870) to the middle of the 70s, there were at least two other ways to the regional economic integration. One of them happened with the traditional activities of cattle raising and the extraction of the Paraguay tea (maté/ Yerba Mate) from 1870 to 1937, which divided the regional territory into large farmlands focused on the external market. The other way happened with the need to create a market for the agricultural production and for the demand for manufactured goods, which reorganized the regional territory into small farmlands, as a result of colonization projects from 1943 to 1956. Since 1976, with the creation of the Special Program for the Development of the Great Dourados Region (Prodegran), the capitalist relations of production, which were consolidated in the area, were not ruled almost exclusively by the traditional activities of cattle raising and the extraction of the Paraguay tea, in order to create a new accumulation center connected to the modern crops. As this new accumulation center was created, the Region was led to a selective and dependent integration process, in which many farmers changed their accumulation centers to modern grain crops, causing environmental degradation, productive exclusion and ethnical-cultural conflicts with the indigenous community

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Wetlands store large amounts of carbon, and depending on their status and type, they release specific amounts of methane gas to the atmosphere. The connection between wetland type and methane emission has been investigated in various studies and utilized in climate change monitoring and modelling. For improved estimation of methane emissions, land surface models require information such as the wetland fraction and its dynamics over large areas. Existing datasets of wetland dynamics present the total amount of wetland (fraction) for each model grid cell, but do not discriminate the different wetland types like permanent lakes, periodically inundated areas or peatlands. Wetland types differently influence methane fluxes and thus their contribution to the total wetland fraction should be quantified. Especially wetlands of permafrost regions are expected to have a strong impact on future climate due to soil thawing. In this study ENIVSAT ASAR Wide Swath data was tested for operational monitoring of the distribution of areas with a long-term SW near 1 (hSW) in northern Russia (SW = degree of saturation with water, 1 = saturated), which is a specific characteristic of peatlands. For the whole northern Russia, areas with hSW were delineated and discriminated from dynamic and open water bodies for the years 2007 and 2008. The area identified with this method amounts to approximately 300,000 km**2 in northern Siberia in 2007. It overlaps with zones of high carbon storage. Comparison with a range of related datasets (static and dynamic) showed that hSW represents not only peatlands but also temporary wetlands associated with post-forest fire conditions in permafrost regions. Annual long-term monitoring of change in boreal and tundra environments is possible with the presented approach. Sentinel-1, the successor of ENVISAT ASAR, will provide data that may allow continuous monitoring of these wetland dynamics in the future complementing global observations of wetland fraction.

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Led to become a national productive Center, the Great Dourados Region, which consists of 40 cities located in the south of the state of Mato Grosso do Sul - Brazil, emerged as a grain productive region from the middle of the 1970s in the 20th century to the beginning of the 21st century. Using modern agricultural techniques, the land organization in this region was ruled by a development policy which was not concerned with the socio environmental aspects of the area. In this context, the present work aims to analyze the development process of the Great Dourados region, through soybean production and its relation to the confinement of the indigenous people present in the Area. This integration happened due to the money and for it, inserting this Region into a national productive pattern which guided the farmers to modern crops, mainly soybean. The land cultivation was not the only productive activity that granted the Region an economic integration, to both the national and international market. From the end of the Paraguay War (1870) to the middle of the 70s, there were at least two other ways to the regional economic integration. One of them happened with the traditional activities of cattle raising and the extraction of the Paraguay tea (maté/ Yerba Mate) from 1870 to 1937, which divided the regional territory into large farmlands focused on the external market. The other way happened with the need to create a market for the agricultural production and for the demand for manufactured goods, which reorganized the regional territory into small farmlands, as a result of colonization projects from 1943 to 1956. Since 1976, with the creation of the Special Program for the Development of the Great Dourados Region (Prodegran), the capitalist relations of production, which were consolidated in the area, were not ruled almost exclusively by the traditional activities of cattle raising and the extraction of the Paraguay tea, in order to create a new accumulation center connected to the modern crops. As this new accumulation center was created, the Region was led to a selective and dependent integration process, in which many farmers changed their accumulation centers to modern grain crops, causing environmental degradation, productive exclusion and ethnical-cultural conflicts with the indigenous community

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Led to become a national productive Center, the Great Dourados Region, which consists of 40 cities located in the south of the state of Mato Grosso do Sul - Brazil, emerged as a grain productive region from the middle of the 1970s in the 20th century to the beginning of the 21st century. Using modern agricultural techniques, the land organization in this region was ruled by a development policy which was not concerned with the socio environmental aspects of the area. In this context, the present work aims to analyze the development process of the Great Dourados region, through soybean production and its relation to the confinement of the indigenous people present in the Area. This integration happened due to the money and for it, inserting this Region into a national productive pattern which guided the farmers to modern crops, mainly soybean. The land cultivation was not the only productive activity that granted the Region an economic integration, to both the national and international market. From the end of the Paraguay War (1870) to the middle of the 70s, there were at least two other ways to the regional economic integration. One of them happened with the traditional activities of cattle raising and the extraction of the Paraguay tea (maté/ Yerba Mate) from 1870 to 1937, which divided the regional territory into large farmlands focused on the external market. The other way happened with the need to create a market for the agricultural production and for the demand for manufactured goods, which reorganized the regional territory into small farmlands, as a result of colonization projects from 1943 to 1956. Since 1976, with the creation of the Special Program for the Development of the Great Dourados Region (Prodegran), the capitalist relations of production, which were consolidated in the area, were not ruled almost exclusively by the traditional activities of cattle raising and the extraction of the Paraguay tea, in order to create a new accumulation center connected to the modern crops. As this new accumulation center was created, the Region was led to a selective and dependent integration process, in which many farmers changed their accumulation centers to modern grain crops, causing environmental degradation, productive exclusion and ethnical-cultural conflicts with the indigenous community

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The Lena River Delta, which is the largest delta in the Arctic, extends over an area of 32 000 km**2 and likely holds more than half of the entire soil organic carbon (SOC) mass stored in the seven major deltas in the northern permafrost regions. The geomorphic units of the Lena River Delta which were formed by true deltaic sedimentation processes are a Holocene river terrace and the active floodplains. Their mean SOC stocks for the upper 1 m of soils were estimated at 29 kg/m**2 ± 10 kg/m**2 and at 14 kg/m**2 ± 7 kg/m**2, respectively. For the depth of 1 m, the total SOC pool of the Holocene river terrace was estimated at 121 Tg ± 43 Tg, and the SOC pool of the active floodplains was estimated at 120 Tg ± 66 Tg. The mass of SOC stored within the observed seasonally thawed active layer was estimated at about 127 Tg assuming an average maximum active layer depth of 50 cm. The SOC mass which is stored in the perennially frozen ground at the increment 50-100 cm soil depth, which is currently excluded from intense biogeochemical exchange with the atmosphere, was estimated at 113 Tg. The mean nitrogen (N) stocks for the upper 1 m of soils were estimated at 1.2 kg/m**2 ± 0.4 kg/m**2 for the Holocene river terrace and at 0.9 kg/m**2 ± 0.4 kg/m**2 for the active floodplain levels, respectively. For the depth of 1 m, the total N pool of the river terrace was estimated at 4.8 Tg ± 1.5 Tg, and the total N pool of the floodplains was estimated at 7.7 Tg ± 3.6 Tg. Considering the projections for deepening of the seasonally thawed active layer up to 120 cm in the Lena River Delta region within the 21st century, these large carbon and nitrogen stocks could become increasingly available for decomposition and mineralization processes.

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Arctic permafrost may be adversely affected by climate change in a number of ways, so that establishing a world-wide monitoring program seems imperative. This thesis evaluates possibilities for permafrost monitoring at the example of a permafrost site on Svalbard, Norway. An energy balance model for permafrost temperatures is developed that evaluates the different components of the surface energy budget in analogy to climate models. The surface energy budget, consisting of radiation components, sensible and latent heat fluxes as well as the ground heat flux, is measured over the course of one year, which has not been accomplished for arctic land areas so far. A considerable small-scale heterogeneity of the summer surface temperature is observed in long-term measurements with a thermal imaging system, which can be reproduced in the energy balance model. The model can also simulate the impact of different snow depths on the soil temperature, that has been documented in field measurements. Furthermore, time series of terrestrial surface temperature measurements are compared to satellite-borne measurements, for which a significant cold-bias is observed during winter. Finally, different possibilities for a world-wide monitoring scheme are assessed. Energy budget models can incorporate different satellite data sets as training data sets for parameter estimation, so that they may constitute an alternative to purely satellite-based schemes.

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Space competition between corals and seaweeds is an important ecological process underlying coral-reef dynamics. Processes promoting seaweed growth and survival, such as herbivore overfishing and eutrophication, can lead to local reef degradation. Here, we present the case that increasing concentrations of atmospheric CO2 may be an additional process driving a shift from corals to seaweeds on reefs. Coral (Acropora intermedia) mortality in contact with a common coral-reef seaweed (Lobophora papenfussii) increased two- to threefold between background CO2 (400 ppm) and highest level projected for late 21st century (1140 ppm). The strong interaction between CO2 and seaweeds on coral mortality was most likely attributable to a chemical competitive mechanism, as control corals with algal mimics showed no mortality. Our results suggest that coral (Acropora) reefs may become increasingly susceptible to seaweed proliferation under ocean acidification, and processes regulating algal abundance (e.g. herbivory) will play an increasingly important role in maintaining coral abundance.

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Thermokarst lakes are typical features of the northern permafrost ecosystems, and play an important role in the thermal exchange between atmosphere and subsurface. The objective of this study is to describe the main thermal processes of the lakes and to quantify the heat exchange with the underlying sediments. The thermal regimes of five lakes located within the continuous permafrost zone of northern Siberia (Lena River Delta) were investigated using hourly water temperature and water level records covering a 3-year period (2009-2012), together with bathymetric survey data. The lakes included thermokarst lakes located on Holocene river terraces that may be connected to Lena River water during spring flooding, and a thermokarst lake located on deposits of the Pleistocene Ice Complex. Lakes were covered by ice up to 2 m thick that persisted for more than 7 months of the year, from October until about mid-June. Lake-bottom temperatures increased at the start of the ice-covered period due to upward-directed heat flux from the underlying thawed sediment. Prior to ice break-up, solar radiation effectively warmed the water beneath the ice cover and induced convective mixing. Ice break-up started at the beginning of June and lasted until the middle or end of June. Mixing occurred within the entire water column from the start of ice break-up and continued during the ice-free periods, as confirmed by the Wedderburn numbers, a quantitative measure of the balance between wind mixing and stratification that is important for describing the biogeochemical cycles of lakes. The lake thermal regime was modeled numerically using the FLake model. The model demonstrated good agreement with observations with regard to the mean lake temperature, with a good reproduction of the summer stratification during the ice-free period, but poor agreement during the ice-covered period. Modeled sensitivity to lake depth demonstrated that lakes in this climatic zone with mean depths > 5 m develop continuous stratification in summer for at least 1 month. The modeled vertical heat flux across the bottom sediment tends towards an annual mean of zero, with maximum downward fluxes of about 5 W/m**2 in summer and with heat released back into the water column at a rate of less than 1 W/m**2 during the ice-covered period. The lakes are shown to be efficient heat absorbers and effectively distribute the heat through mixing. Monthly bottom water temperatures during the ice-free period range up to 15 °C and are therefore higher than the associated monthly air or ground temperatures in the surrounding frozen permafrost landscape. The investigated lakes remain unfrozen at depth, with mean annual lake-bottom temperatures of between 2.7 and 4 °C.

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Economic development in East Asia is characterized by the sequential "take-off" of member countries. This multi-tiered economic development in East Asia is often termed the “Flying Geese” pattern of economic development. However, some authors argue that the traditional Flying Geese pattern is not applicable to some industries such as electronics. Here, Japan may no longer be the sole "leading goose", with "followers" such as China (now producing cutting-edge products) having "caught-up". Does this mean that the Flying Geese Model has become "obsolete" in the 21st century? The main objective of this paper is to clarify the two concepts of Flying Geese which now seem confused: (1) application of the pattern of economic development in one specific country, and (2) application of the pattern of economic development to multiple countries in sequence. This paper provides validity checks of Flying Geese Models after differentiating these two concepts more clearly