930 resultados para Spatial concentration and centralization of economic activities
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New volumetric and mass flux estimates have been calculated for the Kenya Rift. Spatial and temporal histories for volcanic eruptions, lacustrine deposition, and hominin fossil sites are presented, aided by the compilation of a new digital geologic map. Distribution of volcanism over time indicates several periods of southward expansion followed by relative positional stasis. Volcanism occurs throughout the activated rift length, with no obvious abandonment as the rift system migrated. The main exception is a period of volcanic concentration around 10 Ma, when activity was constrained within 2° of the equator. Volumes derived from seismic data indicate a total volume of c. 310,000 km3 (2.47 x 1010 kg/yr ), which is significantly more than the map-derived volumes found here or published previously. Map-based estimates are likely affected by a bias against recognizing small volume events in the older record. Such events are, however, the main driver of erupted volume over the last 5 Ma. A technique developed here to counter this bias results in convergence of the two volume estimation techniques. Relative erupted composition over time is variable. Overall, the erupted material has a mafic to silicic ratio of 0.9:1. Basalts are distinctly more common in the Turkana region, which previously experienced Mesozoic rifting. Despite the near equal ratio of mafic to silicic products, the Kenya Rift otherwise fits the definition of a SLIP. It is proposed that the compositions would better fit the published definition if the Turkana region was not twice-rifted. Lacustrine sedimentation post-dates initial volcanism by about 5 million years, and follows the same volcanic trends, showing south and eastward migration over time. This sedimentation delay is likely related to timing of fault displacements. Evidence of hominin habitation is distinctly abundant in the northern and southern sections of the Kenya Rift, but there is an observed gap in the equatorial rift between 4 and 0.5 million years ago. After 0.5 Ma, sites appear to progress towards the equator. The pattern and timing of hominid site distributions suggests that the equatorial gap in habitation may be the result of active volcanic avoidance.
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The Socio-Economic Atlas of Kenya is the first of its kind to offer high-resolution spatial depictions and analyses of data collected in the 2009 Kenya Population and Housing Census . The combination of geographic and socio-eco - nomic data enables policymakers at all levels, development experts, and other interested readers to gain a spatial understanding of dynamics affecting Kenya. Where is the informal economic sector most prominent? Which areas have adequate water and sanitation? Where is population growth being slowed effectively? How do education levels vary throughout the country? And where are poverty rates lowest? Answers to questions such as these, grouped into seven broad themes, are visually illustrated on high-resolution maps. By supplying precise information at the sub-location level and summarizing it at the county level, the atlas facilitates better planning that accounts for local contexts and needs. It is a valuable decision-support tool for government institutions at different administrative levels, educational institutions, and others. Three organizations – two in Kenya and one in Switzerland – worked together to create the atlas: the Kenya National Bureau of Statistics (KNBS), the Nanyuki-based Centre for Training and Integrated Research in ASAL Development (CETRAD), and the Centre for Development and Environment (CDE) at the University of Bern. Close cooperation between KNBS, CETRAD, and CDE maximized synergies and knowledge exchange.
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Native trees and shrubs are essential components of rural landscapes in the semi-arid inner-Andean valleys of Bolivia. They can be found as hedges and bushes in various agroecosystems such as terrace walls, slopes, field boundaries and fallow land. Their distribution and floristic composition are the result of dynamic spatial and temporal interactions between local farmers and the environment. Local uses of natural resources and biodiversity reflect the constantly evolving Andean culture, which can be generally characterised as an intertwining of the human, natural, and spiritual worlds. The aim of the present ethnobotanical study was to analyse the dynamics of traditional ecological knowledge, to ascertain local farmers’ perceptions and uses of native woody species in Andean communities and to associate the results with local conservation activities for the trees and shrubs concerned. Our case study was carried out within two communities of the Tunari National Park (Dept. Cochabamba) in Bolivia. For data collection, research methods from social science (semi-structured interviews, participative observation, participatory mapping) as well as vegetation surveys were combined. Local actors included women and men of all ages as well as families from different social categories and altitudinal levels of permanent residence. Our study indicates that, due to a multitude of socio-economic pressures (e.g. migration of young people) as well as changes in use of biodiversity (e.g. replacement of native by exotic introduced species), the traditional ecological knowledge base of native trees and shrubs and their respective uses has become diminished over time. In many cases it has led to a decline in people’s awareness of native species and as a consequence their practical, emotional and spiritual relationships with them have been lost. However, results also show that applied traditional ecological knowledge has led to local conservation strategies, which have succeeded in protecting those tree and shrub species which are most widely regarded for their multifunctional, constant and exclusive uses (e.g. Schinus molle, Prosopis laevigata, Baccharis dracunculifolia). The presentation will discuss the question if and how applied traditional ecological knowledge positively contributes to local initiatives of sustainable use and conservation of biodiversity in rural areas.
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The main goals of this study were to identifythe alpine torrent catchments that are sensitive to climatic changes and to assess the robustness of the methods for the elaboration of flood and debris flow hazard zone maps to specific effects of climate changes. In this study, a procedure for the identification and localization of torrent catchments in which the climate scenarios will modify the hazard situation was developed. In two case studies, the impacts of a potential increase of precipitation intensities to the delimited hazard zones were studied. The identification and localization of the torrent and river catchments, where unfavourable changes in the hazard situation occur, could eliminate speculative and unnecessary measures against the impacts of climate changes like a general enlargement of hazard zones or a general over dimensioning of protection structures for the whole territory. The results showed a high spatial variability of the sensitivity of catchments to climate changes. In sensitive catchments, the sediment management in alpine torrents will meet future challenges due to a higher rate for sediment removal from retention basins. The case studies showed a remarkable increase of the areas affected by floods and debris flow when considering possible future precipitation intensities in hazard mapping. But, the calculated increase in extent of future hazard zones lay within the uncertainty of the methods used today for the delimitation of the hazard zones. Thus, the consideration of the uncertainties laying in the methods for the elaboration of hazard zone maps in the torrent and river catchments sensitive to climate changes would provide a useful instrument for the consideration of potential future climate conditions. The study demonstrated that weak points in protection structures in future will become more important in risk management activities.
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Standing stocks and production rates for phytoplankton and heterotrophic bacteria were examined during four expeditions in the western Arctic Ocean (Chukchi Sea and Canada Basin) in the spring and summer of 2002 and 2004. Rates of primary production (PP) and bacterial production (BP) were higher in the summer than in spring and in shelf waters than in the basin. Most surprisingly, PP was 3-fold higher in 2004 than in 2002; ice-corrected rates were 1581 and 458 mg C/m**2/d respectively, for the entire region. The difference between years was mainly due to low ice coverage in the summer of 2004. The spatial and temporal variation in PP led to comparable variation in BP. Although temperature explained as much variability in BP as did PP or phytoplankton biomass, there was no relationship between temperature and bacterial growth rates above about 0°C. The average ratio of BP to PP was 0.06 and 0.79 when ice-corrected PP rates were greater than and less than 100 mg C/m**2/d, respectively; the overall average was 0.34. Bacteria accounted for a highly variable fraction of total respiration, from 3% to over 60% with a mean of 25%. Likewise, the fraction of PP consumed by bacterial respiration, when calculated from growth efficiency (average of 6.9%) and BP estimates, varied greatly over time and space (7% to >500%). The apparent uncoupling between respiration and PP has several implications for carbon export and storage in the western Arctic Ocean.
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In this paper, based on the recent advances in the new economic geography (e.g., Fujita, Krugman and Venables [12]), we analyze impacts of transport costs on the spatial patterns of economic agglomeration. We first identify prototypes from the existing models, and explain the mechanism of how transport costs influence the balance between economic forces of agglomeration and dispersion. We then investigate the transformation of the agglomeration/dispersion patterns given gradually decreasing transport costs for different goods.
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The change in the ownership structure of enterprises was one of the major features of the Vietnamese economy in the 2000s. Of the three sectors of state, private and FDI, the state sector, which employed the majority of enterprise workers at the beginning of the 2000s, became the smallest by the end of the decade. One of the factors contributing to such phenomenon was SOE restructuring. Earlier SOE restructuring in the early 1990s is said to have resulted in increased economic inequality among provinces. The purpose of this paper is to clarify the impact of the SOE restructuring and related changes in the ownership structure of enterprises on the regional distribution of economic activities in the 2000s.
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This paper examines the conventional assumption that bilateral transport costs are symmetric. We develop an economic geography model with transport sector in which asymmetric freight rates can occur as a result of density economies. Comparing this to models without density economies, we show that agglomeration of economic activities is more likely to emerge and that multiple equilibria can emerge for some parameters. Then we show the change in its bifurcation and stability of equilibrium and conclude that economies of density in transport flows can act as an agglomeration force.
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The Mount Antero/White area is a popular prospecting area. Recent expansions in the recreation economy is drawing more visitors to the area. Consequently, visitors may be placing unsustainable pressures on the landscape. In order to help rectify this, the legal, ecological, geologic, aesthetic, recreational, historic, social, and economic character of the Antero/White area has been identified. Four feasible management alternatives have also been recognized. They are a) take no new management actions, b) prohibit motorized activities in the area, c) develop a mineralogical park, and d) a combination of options b and c. Option C has been defended, as it best balances the desires of area users with the underlying ecological and geological character of the area.
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[Introduction.] It is generally believed that while the principle of the autonomy of the EU legal order, in the sense of constitutional and institutional autonomy that is to say what concerns the autonomous decision-making of the EU, has been clearly strengthened by the most recent jurisprudence of the Court of Justice (eg. Moxplant3, Intertanko or the Kadi/Al Baraakat judgements or the Opinion 1/2009 of the CJEU etc.) as well as, in my opinion, in many aspects by the Treaty of Lisbon, it is still valid to add that the principle of a favourable approach, stemming from the Court jurisprudence, for the enhanced openness of the EU legal order to international law has remained equally important for the EU4. On the other hand, it should be also seen that in a globalized world, and following the increased role of the EU as an international actor, its indispensable and crucial role concerning the creation of world (legal) order in many policy fields ( for example let's think about the G20 issues, the global economic and financial crisis, the role of the EU in promoting and protecting human rights worldwide, the implementation of the multilateral or regional conventional law, developed in the framework the UN (e.g. in the field of agriculture or environment etc) or what concerns the Kyoto process on climate change or the conservation of marine biological resources at international level etc), it seems reasonable and justified to submit that the influence, for example, of the law-making activities of the main stakeholder international organizations in the mentioned policy-areas on the EU (especially on the development of its constantly evolving legal order) or vice-versa the influence of the EU law-making practice on these international organizations is significant, in many aspects mutually interdependent and more and more remarkable. This tendency of the 21st century doesn't mean, however, in my view, that the notion of the autonomy of the EU legal order would have been weakened by this increasing interaction between international law and EU law over the passed years. This contribution is going to demonstrate and prove these departuring points by giving some concrete examples from the most recent practice of the Council (all occuring either in the second half of 2009 or after the entry into force of the Lisbon Treaty), and which relate to two very important policy areas in the EU, namely the protection of human rights and the Common Fishery Policy.
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