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1.
Measurement of photosynthetic pigments as ground truth for remotely sensed spectra of boreal communities was tested. Chlorophyll and carotenoid concentrations and ratios were obtained from needles of spruce trees which were healthy as well as those undergoing forest decline (Waldsterben) in Vermont (USA) and Baden-Württemberg (FR Germany). In needles of trees exhibiting forest decline symptoms, chlorophyll pigment concentrations were lower, chlorophyll b levels decreased relative to chlorophyll a, total chlorophyll (a + b) was less relative to total carotenoid, and percent of reflectance in the visible range was higher. Pigment and reflectance data differentiated between needles from healthy and declining sites. These results were compared to remotely sensed spectral data obtained by aircraft and satelitee. As a result of these initial comparisons, it appears that using photosynthetic pigments as ground truth for remotely sensed spectral data may be of value in developing techniques for differentiating undamaged and damaged tree canopies on a large spatial scale. Finally, similar pigment and reflectance properties characterized healthy and declining communities in both Vermont and Baden-Württemberg.  相似文献   

2.
This paper analyzes the potential of earthquake early-warning systems for transport lines. The interdisciplinary work focuses on rapidly producing an alert map during an ongoing earthquake as well as providing a damage map immediately after the strong-motion phase that visualizes potential damages to the railway infrastructure. In order to meet these application requirements, a service-oriented architecture based on geospatial standards is specified. This ensures the portability of the system architecture to different geographic regions as well as a potential transfer to other natural disasters and infrastructure systems. The first part of the paper describes the standard-based services of the system architecture together with design principles that are useful for the realization of early-warning systems. In the second part of the paper, an online demonstrator for the exemplary test area in the federal state of Baden-Württemberg, Germany, is presented. The system architecture of the demonstrator includes an earthquake early-warning methodology based on artificial neural networks and an infrastructure-specific damage assessment. The third part of the paper analyzes the potential of implementing low-cost sensors in the track, which would provide a dense network directly at the railway infrastructure.  相似文献   

3.
4.
In the present paper the results of experimental and numerical investigations of hygro-thermo-mechanical properties of “Schilfsandstein” from Baden-Württemberg are presented and discussed. The aim of the study was to investigate the influence of extreme environmental conditions causing severe damage that can often be observed on various monuments during restoration and reconstruction process. In the experimental investigations the stone specimen was exposed to extreme hygro-thermal conditions, which caused significant damage (cracking). During the experiment the ultrasonic and acoustic emission analyses were performed. Subsequently, a 3D finite element analysis was carried out using a coupled hygro-thermo-mechanical model for stone. The experimental and numerical results indicate that wetting in combination with either decrease or increase of temperature lead to severe damage. The most critical locations for initialization of cracks are sharp spikes (notches), or acute angles that are inward or outward oriented (corners). Stiff but brittle layers, like late diagenetic iron cementations, might be a weak point for the initialization of crack. Furthermore, the bedding direction (anisotropy) seems to be a preferred direction for crack propagation. The results of the numerical analysis are in relatively good agreement with experimental observations.  相似文献   

5.
In Württemberg, the upper part of the Middle Keuper is referred to as “Knollenmergel” (= “nodular marl”, a marly claystone containing carbonate nodules), 24 samples were studied from a test well located near Hechingen. X-ray diffraction was used for the determination of the mineral composition of whole rocks and of the clay fractions. The coarser fractions were studied under the petrographic microscope. The fractions < 2π Ø consist chiefly of an mixed-layer mineral with illite and expandable, montmorillonite-like layers as the components. There are about 30 % of expandable layers. A low-angle reflection near 31 Å is indicative of considerable order among component-layer species approaching that of rectorite. In the lower part of the section, moderate amounts of sudoite are present in addition. Illite as a discrete phase could not be determined with certainty. The microscopic fractions consist partly of monomineralic grains of quarz, dolomite, and calcite. In addition, they contain considerable amounts of polymineralic aggregates, which were not dispersed by the rather mild disintegration method used in the present study. Accordingly, the rocks are claystones characterized by the same degree of lithification as those occurring in other parts of the Keuper in Württemberg. The interstratified mineral is tentatively derived from the erosion of a uniform body of volcanogenic material of Paleozoic age. On the basis of grain-size distribution, the Knollenmergel is a water-laid sediment. Eolian transport as advocated by some geologists can be excluded. The difficulties experienced with the Knollenmergel as a building ground are explained by the high percentage of the expandable interstratified mineral and the dearth of a genuine sand fraction.  相似文献   

6.
The famous spa of Baden-Baden is situated in the northern Black Forest area not far from the upper Rhine valley in southwestern Germany. Its natural sodium chloride thermal water (68°C), together with its extremely mild climate and pleasant landscape, made Baden-Baden one of the most favored spas in Germany. Baden-Baden was a former capital of the German state of Baden (which means bath or spa), and its name is now included in the name of the state of Baden-Württemberg. Thus, Baden-Württemberg is the only area in Germany where a geologic phenomenon is part of the name of the state.  相似文献   

7.
Thea Dukes 《GeoJournal》2008,72(1-2):105-119
The European Community Initiative URBAN, explored in this article for seven countries in general and for two individual cities in the Netherlands in more detail, is a micro example of the ongoing struggle between European and national policy actors who contest each others’ authority. The programme, aimed at solving social-economic problems in deprived neighbourhoods in European cities, has acted as a catalyst for new forms of cooperation.Whether it has directly contributed to Europeanization at the local level seems questionable, but it has certainly helped some city administrations to enter the European stage. Whereas European urban policy discourse could not be found at the Dutch urban level in the mid 1990s, the discourse has become dispersed and is now increasingly used.  相似文献   

8.
Béla Kádár 《GeoJournal》1994,32(4):327-327
This short article describes the present changed direction of the Hungarian foreign trade, emphasising the orginal, traditional tendencies re-occurring and coming to be dominant without any governmental measures or pressure. This is the reviving trade with three German provinces: Bavaria, Baden-Württemberg and North Rhineland-Westphalia. It is a pity that the traditional commercial links were not restored with Saxony and Thuringia, and also, that the northern German regions are not yet involved in Hungarian foreign trade to a greater degree.  相似文献   

9.
The dominance of “ecosystem services” as a guiding concept for environmental management – where it appears as a neutral, obvious, taken-for-granted concept – hides the fact that there are choices implicit in its framing and in its application. In other words, it is a highly political concept, and its utility depends on the arena in which it is used and what it is used for. Following a political ecology framework, and based on a literature review, bibliometric analyses, and brief examples from two tropical rainforest countries, this review investigates four moments in the construction and application of the ecosystem services idea: socio-historical (the emergence of the discourse), ontological (what knowledge does the concept allow?), scientific (difficulties in its practical application), and political (who wins, who loses?). We show how the concept is a boundary object with widespread appeal, trace the discursive and institutional context within which it gained traction, and argue that choices of scale, definition, and method in measuring ecosystem services frustrate its straightforward application. As a result, it is used in diverse ways by different interests to justify different kinds of interventions that at times might be totally opposed. In Madagascar, the ecosystem services idea is mainly used to justify forest conservation in ways open to critique for its neoliberalization of nature or disempowerment of communities. In contrast, in the Brazilian Amazon, the discourse of ecosystem services has served the agendas of traditional populations and family farm lobbies. Ecosystem services, as an idea and tool, are mobilized by diverse actors in real-life situations that lead to complex, regionally particular and fundamentally political outcomes.  相似文献   

10.
This article contributes to the study of changing climate discourse and policy in emerging powers through a case study of climate discourse in India since 2007. Based on interviews with key actors in Indian climate politics and textual analysis, three general climate discourses – the Third World, Win–Win and Radical Green discourses – are identified. The discourses are characterised by different constructions of India’s identity, interests, climate change exposure and climate policy orientation. At the most general level, the article finds that there has been a general discursive shift from the Third World discourse to the Win–Win discourse, and that the latter discourse is in broad agreement with the dominant international climate change discourse of ecological modernisation and thus supports an alignment between Indian and international climate politics. We also find, however, that India’s domestic climate politics is marked by co-existence and tensions between the three climate discourses, producing a complex and at times contentious discursive politics over climate change, identity and development. The case study presented in this article moreover demonstrates how national interests are socially constructed and how changes in policy reflect changes in the dominant discourse.  相似文献   

11.
This paper demonstrates how the global commodity chain approach has mutated from a critical tool for studying the production of inequality in the global economy to an instrument of development policy that extends the frontiers of marketization to so-called “peripheries” in the Global South. Taking an outgrower scheme for the global production of organic mangoes in northern Ghana as point of departure, and situating this case study within the broader context of market experiments in the Ghanaian agricultural sector, it develops an account of global capitalism as a diverse, heterogeneous and messy arrangement of local borderlands. As a zone of inclusive exclusion these borderlands are brought into being by an economic discourse which separates the inside of the capitalist world from its supposed outside. The so-called integration of smallholders into global markets relies on exclusionary representations and the forging of new associations. First, economic practices in northern Ghana are portrayed by economists as defective and in doing so determine what lies outside the market. Second, within this “outside” – on which the “inside” actually depends – global capitalism mediated through the market models and rhetoric of international development organizations now literally touches the ground in specific geographical settings. Hence Frontier regions as represented by our case study bear the paradoxical character of the work of economics and are an instructive example for the performative power of economic theories. Marketization is revealed as a complex and socio-technically entangled process full of hidden prerequisites and unforeseen consequences that open up new social spaces of multiple ontological reconfigurations.  相似文献   

12.
This paper aims to discuss the possibilities of adopting a policy based on collective learning in old industrial regions. This is particularly interesting because old industrial regions are believed to have lost their learning capabilities, as indicated by notions of `technological' and `institutional' lock-in. Moreover, the success stories where positive effects of interactive learning have been observed (Silicon Valley, Baden-Württemberg) all share the lack of an industrial past.First, we specify how a theoretical framework based on interactive learning, which tries to explain the industrial decline of old agglomerations, may look like, and how such an approach differs from other approaches. Then, we set out a policy framework that aims to deal with the process of structural adjustment and which incorporates the ideas of interactive learning based on socio-cultural factors. In this respect, we distinguish between two possible routes of adjustment, which reveal a complex interplay between different types of agglomeration economies, innovations and restructuring processes. Finally, we devote attention to the problems such a policy based on the notion of the learning region may face, such as the problem of how to overcome a negative lock-in situation caused by localized path dependency.  相似文献   

13.
Prytherch  David L.  Huntoon  Laura 《GeoJournal》2005,62(1-2):41-50
European politics and planning have recently been characterized by a shift to economic entrepreneurialism at sub-national scales, and the planned redevelopment of the city-region in pursuit of global competitiveness, which scholars have interpreted in light of political-economic “rescaling” or regionalization and the emergence of a “new regionalism.” Analyzing rescaling largely in terms of shifting economic and institutional structures, however, many accounts underestimate the complexity and enduring power of so-called ‘old’ regionalist politics of culture and identity as backdrop to urban redevelopment planning. In this paper we address how the urban planning process mediates between the seemingly dichotomous tendencies of regionalized entrepreneurialism and cultural regionalism. Using case studies of two Spanish autonomous regions and their major urban centers – the Basque Country or Euskadi (Bilbao) and the Comunitat Valenciana (València) – we review the historical geography of planning in the European region in order to explore how cultural regionalism collides with economic rescaling and entrepreneurialism, in and through the planned landscape. We propose that such emerging and hybrid politics and planning be understood as a form of entrepreneurial regionalism, a culturally inflected form of economic competitiveness characteristic of but not unique to the Spanish region. This specific notion of entrepreneurial regionalism may illuminate how planners mediate global and local imperatives within political discourse and landscapes that materialize them, and allow us to better reconceptualize the relationship between economic globalization, state restructuring, and cultural politics in a new Europe of the Regions.  相似文献   

14.
European politics and planning have recently been characterized by a shift to economic entrepreneurialism at sub-national scales, and the planned redevelopment of the city-region in pursuit of global competitiveness, which scholars have interpreted in light of political-economic “rescaling” or regionalization and the emergence of a “new regionalism.” Analyzing rescaling largely in terms of shifting economic and institutional structures, however, many accounts underestimate the complexity and enduring power of so-called ‘old’ regionalist politics of culture and identity as backdrop to urban redevelopment planning. In this paper we address how the urban planning process mediates between the seemingly dichotomous tendencies of regionalized entrepreneurialism and cultural regionalism. Using case studies of two Spanish autonomous regions and their major urban centers – the Basque Country or Euskadi (Bilbao) and the Comunitat Valenciana (València) – we review the historical geography of planning in the European region in order to explore how cultural regionalism collides with economic rescaling and entrepreneurialism, in and through the planned landscape. We propose that such emerging and hybrid politics and planning be understood as a form of entrepreneurial regionalism, a culturally inflected form of economic competitiveness characteristic of but not unique to the Spanish region. This specific notion of entrepreneurial regionalism may illuminate how planners mediate global and local imperatives within political discourse and landscapes that materialize them, and allow us to better reconceptualize the relationship between economic globalization, state restructuring, and cultural politics in a new Europe of the Regions.  相似文献   

15.
The purpose of this paper is to examine the transfer of the green economy from a global discursive level to institutionalization at the national level in Tanzania. While there is a growing amount of research discussing technological aspects of the green economy, less attention has been paid to policy implications and governance aspects, especially in developing countries. There is an increasing emphasis on technological and market-based solutions to environmental challenges globally and in the developed part of the world. However, in developing countries, ‘green growth’ often implies transformed control over natural resources – under schemes that are often driven from abroad. Over the last five to ten years, investments aimed at increasing productivity in the rural agricultural sector in developing countries have become a focus area of the green economy, but various concepts of green have become confused. Such (mis-) interpretation of the green economy has consequences for implementation and outcomes of various ‘green’ projects. Drawing on governmentality as well as the concept of institutional bricolage, I examine how the green economy discourse and policy at the global level have been re-shaped and re-interpreted to fit the existing agri-business initiative of the Southern Agricultural Growth Corridor of Tanzania (SAGCOT), which has been championed as a model for green economy implementation in Africa. I discuss how the green discourse has been ‘grabbed’ as an opportunity to ‘greenwash’ SAGCOT in its establishment and institutionalization.  相似文献   

16.
The difference between bank-based and market-based financial systems is a longstanding and influential conceptual staple of the interdisciplinary literature on finance. This dualistic model has been subjected to wide-ranging critiques over the past decade. Yet, while those critiques productively problematize the relationship between banks and markets presumed by the model, they fail to address the underlying distinction between banks and markets that is also presumed by the model. This article questions that distinction. It argues that financial markets are best understood not as places or platforms where banks and other financial actors come to interact – and thus as essentially separate from banks – but, instead, as, in large part, their interaction; as constituted by it. The article further argues for the political as well as scholarly importance of reconfiguring our ideas of what financial markets are. The idea of markets as separate, reified phenomena not only underpins the scholarly model of bank- and market-based financial systems – it does political work in the wider world, with the appeal to financial markets or, more nebulously, “the market” to rationalize and justify political decision-making having become a commonplace of contemporary public policy discourse.  相似文献   

17.
Until the mid-1980s, transport policy was considered by many as one of the least successful domains of the European integration project. However, from the early 1990s onwards, there are clear signs of a single European transport policy, along with the accompanying implementation of infrastructure projects. What is the explanation for such a change in pace? This paper aims to offer insight in these processes by looking at the mechanisms which form and transform this policy domain. To understand the state of a policy domain and its dynamics over time an institutional approach is taken. Two concepts in political science, ‘policy arrangements’ and ‘supranational governance’ are combined and used as a framework to analyse the European transport policy domain. This analysis describes the development of several elements: organisations, rules, the transnational society, power, resources, and the central transport discourse. It demonstrates that all of these elements have developed from an intergovernmental setting towards a more supranational one. This development was slow in the first decennia when European transport policy was rather passive, but it picked up speed in the 1980s and 1990s. In the pivotal year of 1985, pressure from the transnational society resulted in a rapid change of the rules, the resources and the discourse.  相似文献   

18.
19.
Napoleon Bonaparte was in 1798 the first general to involve geologists as such in a military campaign. But geologists were attached to his army as civilians, without military rank or command function. In contrast, the Prussian general (later Field Marshal) Gebhard von Blücher has generally been credited with first making use of a geologist in military uniform: Professor Karl von Raumer, during the 1813–14 war of German liberation from French Napoleonic domination. Authors have claimed that Blücher consulted Raumer for information on the terrain of Silesia before triumphing over the French at the Battle of the Katzbach in 1813, and that Raumer was therefore the first geologist to help plan a military operation. But is this true? Did Raumer in effect initiate German military use of geology – pioneering the widespread use of geologists, many of them professors, in the 20th century German army?  相似文献   

20.
《Geodinamica Acta》2013,26(4):165-187
Xenoliths found in basaltic lavas provide useful information about the materials of the Earth crust and mantle sampled by the lava on its way to the surface, and they help to extend our interpretations based on geophysical data. A garnet-biotite-hornblende-gneiss xenolith (min. ca. 40 cm across) was drilled at a depth of ca. 18 m in a Tertiary basanite flow at Paszowice village near Jawor, in the easternmost part of the Kaczawa Mountains, central Sudetes (SW Poland). Based on petrography, geochemistry and thermobarometry, the xenolith is interpreted to have been formed at deep crustal levels from a metasedimentary rock. The maximum PT conditions recorded in the gneiss (T 700–740oC, P ca. 10 kbar) indicate that the main metamorphic event took place at a depth of 25–30 km, thus corresponding to the present-day lower crustal level defined on geophysical constraints. The gneiss xenolith contains four zircon populations, as revealed by U-Pb SHRIMP analyses: (1) 1.7 – 2.1 Ga, (2) 547 – 623 Ma, (3) 473 – 494 Ma, and (4) 354 – 437 Ma. The zircons of the youngest group (4) are interpreted to have originated during a metamorphic episode, at ca. 374±3 Ma, corresponding well with the HT-MP major metamorphic event in the neighboring Góry Sowie gneisses and migmatites. A range of features (e.g. the good preservation of the xenolith, lack of significant chemical and thermal interaction with the lava) suggest that the gneiss was sampled by the rising lava on the final path of the magma to the surface, probably from a depth of less than ca. 10 km. That means that the upper crust below this region (underlying the low-grade metamorphic Kaczawa Complex) contains gneisses originally derived from deep-crustal levels, and similar to those locally exposed in the neighborhood (e.g. in the Góry Sowie Massif to the south-east). This interpretation extends our knowledge about the structure and composition of the crust in the eastern part of the European Variscides, which otherwise is inferred only from geophysical data.  相似文献   

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