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941.
This paper analyses how in the aftermath of one of the worst environmental disasters ever to occur in Spain – the Aznalcóllar Disaster – various environmentalist and conservationist groups mobilised migratory birds to bring new insights and the need for new precautions to the controversy elicited by the spill. The case study, thus, revolves around how environmentalists established a “hybrid collective action” to draw attention to unconsidered risks and impacts of the disaster and thereby make the case for open debate. Building upon this, I engage with two different, though interrelated, theoretical debates that contribute to a rethinking of environmental management (EM) as a social and materially situated practice. Drawing on the idea of “tactic” (De Certeau, 1984), I draw attention to the devices, actions and procedures that environmentalists carried out to resist attempts to minimise the spill and to undermine administrations’ assumptions of control, coherence and singularity associated the idea of management. Drawing on Tim Ingold’s latest work (2007, 2008, 2011), I analyse environmentalists’ most successful tactic: the enactment of migratory birds as “lines”. Together with other authors in this special issue, I will use this notion to make an argument against some of the assumptions of the “hybrid ontology”. In contrast to more essentialists and static notions of non-human agency and politics, the idea of line is particularly useful as a way of understanding how nature(s) can be effectuated differently and how this leads to the imagining of new regimes of cohabitation, human and non-human management and intervention.  相似文献   
942.
Analyses of sustainable design and commodity networks often make a priori assumptions about the capacity of markets to provide solutions to environmental problems; and have a tendency to celebrate local scales of action. This paper offers a contrasting account, in which the national state sought to carefully manage scarce natural resources and to ensure equitable consumption at a time of deep crisis. We utilise the historical example of the British wartime Utility furniture scheme in order to draw out three lessons for sustainable and equitable environmental practice. First, we argue that national states do not simply provide an institutional backdrop to sustainable production but rather can act as important organising agents. Second, the paper emphasises that sustainability is best achieved through interventions across a commodity network, beyond simply modifications to a single node such as design. Finally, we underscore the value of ‘pragmatic centralism’ in environmental decision-making, calling attention to the collaborative practices that underpinned the scheme. The example of Utility’s adaptive responses—borne out of crisis, scarcity and shortage during wartime—offers much that is of intrinsic interest to current concerns about resource consumption and the drivers of sustainability in commodity networks.  相似文献   
943.
People’s reasons for visiting national parks have been well researched. So too have their park activities and how diverse activities potentially affect visitors’ park experiences (e.g. perceptions of overcrowding). Far less research has examined how park users’ environmental values might affect their perceptions of other users and the appropriateness of different activities – a potential source of conflict. Relationships between personal environmental values and environmental and social perceptions are complex and interactive in the context of park visitation. Visitors’ encounters with other users can powerfully affect their experience and enjoyment of parks, in turn reflecting such factors as values-related expectations and judgments in the context of national parks. Personal and social values may also play an important role in influencing whether different activities are perceived as ‘out of place’ in the context of national park place meaning, yet the conceptualization of values within geographic literature on parks remains comparatively weak.This paper utilizes a definition of values, derived from a concise review of the geography and social psychology literatures, to explain the results of survey research we undertook within national parks in Queensland, Australia. We use a ‘values-behavior hierarchy’ conceptual framework to consider how the personal environmental values of a sample of park visitors (n = 404) potentially affected patterns of park visitation, user activities, and user conflicts. Findings suggest that visitors’ environmental values shaped how they perceived other park users and the appropriateness of their activities. This has international implications for geographic research and other disciplines and professions involved in national park visitation, park use, and human impacts, on and of these powerful places.  相似文献   
944.
A rapidly growing literature interrogates the social and economic impacts of various Reducing Emissions from Deforestation and Forest Degradation (REDD+) schemes in Sub-Saharan Africa. Less often, however, have scholars examined the necessary corollary of such initiatives; that is, both new and enhanced law enforcement initiatives to combat the global trade in illegal forest products and secure property rights to conserved forests. Drawing upon recent consultative experiences for relevant multinational agencies in East Africa, we critically analyze the emergent features of this additional ‘dark side’ of REDD+, highlighting in particular both its potential for ‘leakage’ effects on adjacent jurisdictions and deleterious implications for forest-dependent communities. Specifically, we highlight the ways in which such activities threaten to conflate illegal with informal trade in forest products; the ways in which they are potentially ill-suited for addressing the trade in charcoal as opposed to the trade in timber; and the incentives that they may provide for states to further marginalize indigenous forest-dwelling populations in the region. In doing so, we argue that this nascent synthesis of REDD+ and transnational law enforcement threatens to contribute significantly and regressively to the broader securitization of conservation in Sub-Saharan Africa and elsewhere.  相似文献   
945.
Beach Profiles surveys and gale climate data were utilised to assess medium timescale beach rotation at four beaches located along the shores of a crenulated embayment within Swansea Bay, Southwest Wales. The proposed Tidal Lagoon is located within this Bay. Results identified a 7 year (1998–2005) record of cyclic summer/winter rotation and a 14 year (1999–2013) record of annual rotation within the subaerial zone on all four assessed beaches. In the absence of headlands to trap sediment it is asserted that the driving force for beach rotation is the presence of Swansea Dockland/Tawe dredged channel complex, Port Talbot Harbour and the Neath dredged channel which form surrogate headlands essentially creating four separate beach systems through restricting sediment by-pass. Seasonal averaged wind and wave variables showed differing correlation with volume changes and cross-correlation results showed that volume variation lagged behind forcing variables by up to six months (i.e. the resolution of the data). This was confirmed by the annually averaged results which showed only subtle correlation. Here volume change in most cases lagged forcing variables by less than one year. Based on correlations, wind direction variability follows closely with volume changes but wind speed, wave period and height are generally opposite. Initial results suggest that the proposed Swansea Bay Tidal Lagoon, located between sediment cells and surrogate headlands, would have little negative effect on subaerial coastal processes. These datasets will be used as a benchmark for monitoring prior to, during and post construction, with results being used to update and inform subsequent strategies.  相似文献   
946.
It is widely accepted that environmental change can influence human migration. In particular, the environment plays a role in migration processes in drylands, in which environmental change—including increasing variability of rainfall, increasing frequency of droughts, chronic water shortage, and land degradation—can heavily influence migration. However, systematic large-scale studies of the relationship between environmental factors and human migration are rare, and a global, consistent picture of environmental drivers of migration is lacking. In this study, we sought to fill this gap by analysing spatial patterns of environmental drivers of migration in drylands by performing a cluster analysis on spatially explicit global data. In this analysis, we focused explicitly on precipitation, aridity, drought, land degradation, soil constraints, and availability of cropland and pastures as potential environmental drivers of migration in drylands. In addition, we linked the identified clusters to two observed hotspots of out-migration—Burkina Faso and Northeast Brazil—to gauge the cluster results. Our results show that environmental drivers can be grouped into eight distinct clusters, and we identified the most severe environmental constraints for each cluster. These results suggest that out-migration—both in absolute and relative terms—occurs most frequently in a cluster that is constrained primarily by land degradation rather than water availability.  相似文献   
947.
A reliance on mathematical modelling is a defining feature of modern global environmental and public health governance. Initially hailed as the vanguard of a new era of rational policy-making, models are now habitually subject to critical analyses. Their quality, in other words, is routinely queried, yet what exactly is quality in this context? The prevailing paradigm views model quality as a multi-dimensional concept, encompassing technical dimensions (e.g. precision and bias), value judgments, problem-framing, treatment of “deep” uncertainties, and pragmatic features of particular decision contexts. Whilst those technical dimensions are relatively simple to characterise, the broader dimensions of quality are less easily formalised and as a result are difficult to take account of during model construction and evaluation. Here, we present a typology of governance regimes (risk-based, precautionary, adaptive and participatory) that helps make explicit what these broader dimensions of model quality are, and sketches out how the emphasis placed on them differs by regime type. We show that these regime types hold distinct positions on what constitutes sound evidence, on how that evidence should be used in policy-making, and to what social ends. As such, a model may be viewed within one regime as providing legitimate evidence for action, be down-weighted elsewhere for reflecting a flawed problem-framing, and outright rejected in another jurisdiction on the grounds that it does not cohere with the preferred ethical framework for decision-making. We illustrate these dynamics by applying our typology to a range of policy domains, emphasising both the disconnects that can occur, as well as the ways that modellers have adapted their practices to ensure that their evidence is brought to bear on policy problems across diverse regime types.  相似文献   
948.
Energy system pathways which are projected to deliver minimum possible deployment cost, combined with low Greenhouse Gas (GHG) emissions, are usually considered as ‘no-regrets’ options. However, the question remains whether such energy pathways present ‘no-regrets’ when also considering the wider environmental resource impacts, in particular those on land and water resources. This paper aims to determine whether the energy pathways of the UK’s Carbon Plan are environmental “no-regrets” options, defined in this study as simultaneously exhibiting low impact on land and water services resulting from resource appropriation for energy provision. This is accomplished by estimating the land area and water abstraction required by 2050 under the four pathways of the Carbon Plan with different scenarios for energy crop composition, yield, and power station locations. The outcomes are compared with defined limits for sustainable land appropriation and water abstraction.The results show that of the four Carbon Plan pathways, only the “Higher Renewables, more energy efficiency” pathway is an environmental “no-regrets” option, and that is only if deployment of power stations inland is limited. The study shows that policies for future low-carbon energy systems should be developed with awareness of wider environmental impacts. Failing to do this could lead to a setback in achieving GHG emission reductions goals, because of unforeseen additional competition between the energy sector and demand for land and water services in other sectors.  相似文献   
949.
贾惠兰  鲁春霞 《中国沙漠》1998,18(3):255-262
以陕-甘天然气输气管道工程为例,根据黄土地区特征,经实地考察和有关资料分析,采用类比分析和事故树结构函数计算法,进行了黄土区输气管道工程环境风险因素识别和环境风险定性与定量分析;得出了不同区段环境风险指数和相对排序;提出了黄土区输气管道环境风险的管理措施与对策,为管道安全施工和运营提供了环境保护依据。  相似文献   
950.
《China Geology》2020,3(2):197-209
Clayey silt reservoirs bearing natural gas hydrates (NGH) are considered to be the hydrate-bearing reservoirs that boast the highest reserves but tend to be the most difficult to exploit. They are proved to be exploitable by the first NGH production test conducted in the South China Sea in 2017. Based on the understanding of the first production test, the China Geological Survey determined the optimal target NGH reservoirs for production test and conducted a detailed assessment, numerical and experimental simulation, and onshore testing of the reservoirs. After that, it conducted the second offshore NGH production test in 1225 m deep Shenhu Area, South China Sea (also referred to as the second production test) from October 2019 to April 2020. During the second production test, a series of technical challenges of drilling horizontal wells in shallow soft strata in deep sea were met, including wellhead stability, directional drilling of a horizontal well, reservoir stimulation and sand control, and accurate depressurization. As a result, 30 days of continuous gas production was achieved, with a cumulative gas production of 86.14 ×104 m3. Thus, the average daily gas production is 2.87 ×104 m3, which is 5.57 times as much as that obtained in the first production test. Therefore, both the cumulative gas production and the daily gas production were highly improved compared to the first production test. As indicated by the monitoring results of the second production test, there was no anomaly in methane content in the seafloor, seawater, and atmosphere throughout the whole production test. This successful production test further indicates that safe and effective NGH exploitation is feasible in clayey silt NGH reservoirs. The industrialization of hydrates consists of five stages in general, namely theoretical research and simulation experiments, exploratory production test, experimental production test, productive production test, and commercial production. The second production test serves as an important step from the exploratory production test to experimental production test.  相似文献   
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