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1.
Trigger levels for fine suspended sediment (FSS) load in streams are required to identify rainfall-runoff events that have significantly elevated FSS loads, compared with expected background loads, as a result of catchment disturbance. Stream FSS load data collected in the mine-impacted Magela Creek catchment in the wet-dry tropics were used to derive water quality management trigger levels for two approaches – a Before-After-Control-Impact Paired difference design (BACIP) and a regression relationship between observed FSS load and corresponding event discharge characteristics. The results indicate that both the BACIP and regression relationship approaches behave similarly, with similar FSS load events elevated above trigger levels. Notwithstanding this, it is recommended that in order to reliably assess the location and magnitude of a catchment disturbance on FSS load, a combination of BACIP and regression relationship approaches must be adopted. In this study, an event with a FSS load above trigger levels associated with both BACIP and the regression relationship fitted for the downstream site is considered to be significantly elevated as a result of a disturbance within the mine-impacted region. While this technique cannot conclusively determine whether the cause of the disturbance is mine-related or natural (such as fire or bank erosion), it is an efficient statistical method of identifying events that warrant further investigation and management action, if required.  相似文献   
2.
The inns and innkeepers of medieval England form a poorly documented and neglected group of institutions and individuals. Yet at a time of growing specialism, they were a crucial part of the economic infrastructure of the country. This study is focused on the documentation for central southern England but seeks to place this in a wider perspective. There was now a regular provision of inns in accordance with the size and importance of the towns. Inns generated substantial rent and were evidently felt to be worth considerable investment. Innkeepers were among the rich and influential members of the town. Inns played a vital role in the evolving and prospering economic, social and political life of the nation in this period.  相似文献   
3.
We analyze the general equilibrium effects of an asymmetric decrease in transport costs, combining a large-scale spatial dynamic general equilibrium model for 267 European NUTS-2 regions with a detailed transport model at the level of individual road segments. As a case study, we consider the impact of the road infrastructure investments in Central and Eastern Europe of the European Cohesion Policy. Our analysis suggests that the decrease in transportation costs benefits the targeted regions via substantial increases in gross domestic product (GDP) and welfare compared to the baseline, and a small increase in population. The geographic information embedded in the transport model leads to relatively large predicted benefits in peripheral countries such as Greece and Finland, which hardly receive funds, but whose trade links cross Central and Eastern Europe, generating profit from the investments there. The richer, Western European nontargeted regions also enjoy a higher GDP after the investment in the East, but these effects are smaller. Thus, the policy reduces interregional disparities. There are rippled patterns in the predicted policy spillovers. In nontargeted countries, regions trading more intensely with regions where the investment is taking place on average benefit more compared to other regions within the same country, but also compared to neighboring regions across an international border. We uncover that regions importing goods from Central and Eastern Europe enjoy the largest spillovers. These regions become more competitive and expand exports, to the detriment of other regions in the same country.  相似文献   
4.
This paper discusses three normative standpoints on conflict in strategic spatial planning: no conflict, conflict for consensus and conflict for meta-consensus on the validity of dispute. These views apply to the questions of whether and why projects, as a major source of conflict, should be identified in the process of strategic planning. In their approaches to these questions, the performance school advocates the production of general guidelines to avoid conflict, the collaborative perspective supports the identification of projects in strategic planning in order to utilize their potential in a conflict-to-consensus journey and the conflict-oriented perspective favours the identification of projects in strategic planning in order to arrive at meta-consensus on the immediate disputability of robust agreements. Reflecting on the collaborative perspective, this paper tests a hypothetical model of how conflicts created in the face of project identification can feed in making consensual strategies. Findings in the North West region of England support the model and suggest some difficulties with reviewing such consensus around which a resistance network forms. The paper puts forward some recommendations for overcoming the review challenge.  相似文献   
5.
Gender differences in mobility patterns between women and men have long been acknowledged. This study analyses how these differences are reproduced in different urban and rural contexts. Using mobility data from a large travel survey taken in 2006 in Spain, we examine the differences between gender mobility through age, modal split and trip purposes. Special attention is paid to how territory shapes mobility and how these territorial settings differently affect gendered mobilities. The use of this data source allows the comparison of all trips made by the total population, including all means of transport. By taking a global view on mobility, the uneven relationships that men and women have with different means of transport become more visible. After disaggregating data by age and territorial settings, results show that women are using sustainable transport modes more often than men, and travelling for more diverse reasons. Gender is thus a fundamental variable in understanding modal split and, by extension, transport sustainability, in terms of energy consumption and the emission of greenhouse gases. From this point of view, we consider women's mobility knowledge and practices – typically related to the most sustainable means of transport – as factors with rising value that could effectively guide public policy in its way to promote more sustainable mobility patterns.  相似文献   
6.
Abstract

This article discusses the issue of the Ming army's maritime shipping of supplies during the second stage of the East Asian War of 1597–8. Despite the lack of historical sources and difficulty in finding accurate numbers, Zhang Yangmeng's 張養蒙 memorials include records of maritime transport decisions, implementation, effectiveness, and limitations and are of great help to filling in the blank areas of research in Ming army logistics.  相似文献   
7.
Granitoid (pegmatite and aplite) veins in metamorphic rocks and intrusive syenites of central Dronning Maud Land, Antarctica, are flanked by conspicuous light‐coloured alteration halos, which represent the damage zone of fracture propagation. The damage zone is characterized by a high density of sealed or healed microcracks, about 1 order of magnitude above background. Fluid inclusions along healed microcracks in quartz of both pegmatite and alteration halos are inspected by optical and scanning electron microscopy, and their composition is analysed by microthermometry and quadrupole mass spectrometry. The similar inclusion record in the granitoid vein and in the damaged host rock indicates the derivation of the fluids from the hydrous melt phase. The aqueous inclusions bear abundant daughter crystals, mainly silicates, and may represent a hydrous melt. The volatile composition is variable in the system H2O–CO2, with mostly subordinate amounts of N2. Phase separation with partitioning of CO2 into the fluid phase coexisting with the hydrous melt, and possibly immiscibility in the subsolidus range, govern fluid evolution during cooling. The variable CO2/N2 ratio suggests mixing with fluids from an external source in the host rock and vigorous circulation at an early stage of high transient permeability. Experiments have shown that healing of microcracks at high temperatures is a matter of hours to weeks, hence similar in time scale to the cooling of the cm‐ to dm‐thick granitoid veins. In this case, rapid cooling and concomitant crack healing in a system undergoing phase separation causes a broad compositional variability of the inclusions due to necking down, and the underpressure developing in closed compartments precludes a meaningful thermobarometric interpretation.  相似文献   
8.
Major corrosion has been found at depth in carbonate hydrocarbon reservoirs from different geologic provinces. Fluid inclusion microthermometry and stable isotopic compositions of carbonate cements, predating major corrosion, constrain the interpretation of the evolution of parental fluids during progressive burial and prior to the major corrosion event. Post‐major corrosion mineral paragenesis includes pyrite (‐marcasite), anhydrite, kaolinite (dickite) and fluorite. Although the post‐corrosion mineral paragenesis represents minor volumes of rock, it may provide valuable insights into the post‐corrosion brine chemistry. Using reactive transport numerical models, the roles of cooling and/or mixing of brines on corrosion have been evaluated as controls for dolomitization, deep burial corrosion and precipitation of the post‐corrosion mineral paragenesis. Modelling results show that cooling of deep‐seated fluids moving upward along a fracture may cause minor calcite dissolution and porosity generation. Significant dolomitization along a fracture zone and nearby host‐rock only occurs when deep‐seated fluids have high salinities (4 mol Cl kg?1 of solution) and Darcian flow rates are relatively high (1 m3 m?2 year?1). Only minor volumes of quartz and fluorite precipitate in the newly formed porosity. Moreover, modelling results cannot reproduce the authigenic precipitation of kaolinite (dickite at high temperatures) by cooling. As an alternative to cooling as a cause of corrosion, mixing between two brines of different compositions and salinities is represented by two main cases. One case consists of the flow up along a fracture of deep‐seated fluids with higher salinities than the fluid in the wall rock. Dolomite does not precipitate at a fracture zone. Nevertheless, minor volumes of dolomite are formed away from the fracture. The post‐corrosion mineral paragenesis can be partly reproduced, and the results are comparable to those obtained from cooling calculations. Minor volumes of quartz and fluorite are formed, and kaolinite‐dickite does not precipitate. The major outputs of this scenario are calcite dissolution and slight net increase in porosity. A second case corresponds to the mixing of low salinity deep‐seated fluids, flowing up along fractures, with high salinity brines within the wall rock. Calculations predict major dissolution of calcite and precipitation of dolomite. The post‐corrosion mineral paragenesis can be reproduced. High volumes of quartz, fluorite and kaolinite‐dickite precipitate and may even completely occlude newly formed porosity.  相似文献   
9.
The generation of computational meshes of complex geological objects is a challenge: their shape needs to be retained, resolution has to adapt to local detail, and variations of material properties in the objects have to be represented. Also mesh refinement and adaptation must be sufficient to resolve variations in the computed variable(s). Here, we present an unstructured hybrid finite element, node‐centred finite‐volume discretization suitable for solving fluid flow, reactive transport, and mechanical partial differential equations on a complex geometry with inhomogeneous material domains. We show that resulting meshes accurately capture free‐form material interfaces as defined by non‐uniform rational B‐spline curves and surfaces. The mesh discretization error is analysed for the elliptic pressure equation and an error metric is introduced to guide mesh refinement. Finite elements and finite volumes are represented in parametric space and integrations are conducted numerically. Subsequently, integral properties are mapped to physical space using Jacobian transformations. This method even retains its validity when the mesh is deformed. The resulting generic formulation is demonstrated for a transport calculation performed on a complex discrete fracture model.  相似文献   
10.
This article puts emphasis on the political representation of tramway projects in Casablanca, Morocco, and Jerusalem, Israel/the Palestinian territories. In this paper, we discuss both tramway projects as flagships of national worlding strategies that try to promote the respective city on global markets of attention, competing for international investors and tourists. As such, they are majorly driven by national political interests, fostering the hegemonic position of the central state in cooperation with private actors. The tramways are aimed at portraying modernity as well as political and economic stability, while aspiring to a supposed international urban world-class. At the same time, governments frame tramways as tools to promote socio-urban integration and to improve local transport systems. However, the paper shows that although governments are eager to stress the integrative role of tramways, they continue with violent politics of urban exclusion at the same time. Thus, the integrative wording behind tramway planning has to be understood against political (and economic) pressures to regain political legitimacy in a moment of crisis - both domestically and internationally. Consequently, the paper uses interview data and applies methods of discourse analysis to shed light on the worlding of tramways and its ambivalent practices of symbolic inclusion and exclusion.  相似文献   
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