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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.
In the Andes, there are several pre-Hispanic irrigation networks with structures destined for water storage. However, it has not been widely discussed in archaeological research. This is probably due to their being difficult to identify. The aim of this study is to explore the use of diatom assemblage analysis as a methodological tool suitable to help in the identification and characterization of these ancient hydraulic structures. We analyzed two archaeological structures interpreted as water reservoirs from north-western Argentina (EH1 in Antofagasta de la Sierra and U-88R1 in Yocavil) and compared them to current reservoirs. The diatom species composition and the changes in the dominant ecological groups in the studied structures highlight different periods of hydraulic behavior. EH1 contained and stored water, but there were periods of time in which there was a lack of use or abandonment of the structure. However, the U88-R1 structure does not have diatom evidence of containing standing water for a prolonged time but presence of wet soils. Thus, the structure could have been used for other water management strategies. The results show that diatom analysis is a methodological tool with a high potential to study ancestral hydrotechnologies.  相似文献   
4.
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   
5.
Zali Fung  Vanessa Lamb 《对极》2023,55(6):1662-1685
We engage geography's longstanding debate on what “counts” as resistance by introducing slow resistance to account for temporal-political strategies against unjust developments, particularly under authoritarian conditions. We draw on over a decade of fieldwork in the Salween River Basin where dams and diversions have been proposed since 1979, including the most recent iteration, the Yuam River water diversion project in Northwest Thailand. We find that resistance by impacted communities and civil society encompasses slow, strategic, and considered actions over time and generations. Such resistance is necessarily protracted to contest developments (re)proposed over decades. By foregrounding the strategic use of time and temporality, we highlight often overlooked actions and strategies of resistance by a diverse range of actors, showing how resistance movements are incremental and interconnected over time, even when “under the radar”. These strategies are key to contesting and (re)shaping the conditions of development in the Basin.  相似文献   
6.
Julia Sizek 《对极》2023,55(6):1898-1918
A proposed project will take water from an aquifer in the California desert to the coast. Lacking final approvals more than 30 years after it started, the project remains a plan despite sizeable opposition. What is its secret? In this paper, I examine the imaginaries of the underground aquifer underneath the lands of Cadiz Inc, the project proponent. While local theories insist the company is at the centre of a Chinatown conspiracy, I argue that the company stays alive through regulatory alchemy, a term that reveals the magic at the heart of scientific and regulatory approval processes. I examine narratives of the aquifer in environmental compliance and financial reporting in order to reveal how regulatory processes become the conditions of profit-making, building on debates in critical legal geography and political ecology.  相似文献   
7.
Much practically orientated environmental research is marked by a polarity between functionalist abstraction and ahistorical normative discourse. This paper seeks to bridge the divide between theoretical and empirical research through a case study of New York City's water supply. Current processes of socio-economic restructuring are leading to negative environmental consequences obscured by a failure to extend analysis beyond limited temporal, spatial or sectoral scales. Insights from regulationist theory show that a combination of fiscal, political and other developments are bringing about a wide-ranging reformulation of existing patterns of environmental regulation and service provision in the city. The power of the state is being radically diminished in relation to the power of capital and a plethora of different interest groups. A relatively simple centralized model of environmental regulation is being transformed into a complex decentralized pattern involving the emergence of new approaches to urban governance. Further research is needed on the contradictions between capitalist accumulation and environmental regulation at different spatial scales in order to link New York's changing role within the global economy to the declining political legitimacy and fiscal capability of the state to play an extensive role in environmental management.  相似文献   
8.
Recent studies have shown that pre-Columbian societies in the Amazon undertook significant landscape modifications, including earthworks. Our fieldwork has revealed that pre-Columbian settlements in the Santarém Region, Lower Amazon, were not limited to the vicinities of permanent water courses, as formerly often assumed. Instead, numerous archaeological sites, dating from ca. a.d. 1300 up to the time of European colonization in the seventeenth century, have been found in an upland area known as the Belterra Plateau, south of the present-day city of Santarém. These upland sites have been found to be associated with particular features in the landscape: cavities or depressions, known locally as “Poços de Água”. LiDAR data shows that a pattern of non-randomly distributed depressions extends far into the densely forested Tapajós National Forest (Flona-Tapajós), allowing us to suggest that the expansion of inland settlement extended considerably farther to the south than what has previously been established through conventional archaeological fieldwork.  相似文献   
9.
A shipwreck from the early 3rd century BC was discovered in the Black Sea's suboxic depths off Ere?li, Turkey, during the 2011 E/V Nautilus expedition. Remote investigation revealed the trawl‐damaged remains of a merchant ship carrying multiple amphora types associated with Aegean and Pontic production areas. Also discovered were elements of the ship's hull that show evidence of both pegged mortise‐and‐tenon and laced construction. The wreck provides crucial archaeological evidence for both maritime connectivity and ship‐construction methods during a period of political and economic transition.  相似文献   
10.
北京大学入藏的秦代水陆里程简册中记载秦代有"阳"县存在,关于这一新出现的秦县,前辈学者认为可能是位于今河南省方城县的秦汉"阳城"。然而,从简册中记载的"阳"县下属各乡到其他地区的距离来看,"阳县"不太可能在今方城附近,而更有可能是位于先秦"唐"国故地的"唐"县。其他出土材料所见的"唐"县一般写作"阳",清华简《系年》中还有楚国曾灭"唐(阳)"置县的明确记载。秦代的阳县应该就是继承了楚灭唐国之后所设的阳县。  相似文献   
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