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961.
In recent years, cities have been portrayed as important loci for transformations of large-scale systems. This paper contributes to scholarship on urban transitions by exploring why the boundaries, functions and challenges of large-scale systems typically are framed differently at the urban level of governance than at more aggregated levels of governance. Empirically, we examine the wastewater system in Denmark by contrasting framings at the urban and national levels over the last 20 years and the transition dynamics that emerged as a consequence of their juxtaposition. The findings illustrate that urban governance of the wastewater system was influenced by a particular concern with developing attractive and competitive urban spaces. The wastewater system emerged as a ‘place-bound’ and even ‘place-making’ governance concern; as such, the boundaries and functions of the system were subject to continuous redefinition at the city level. This urban framing conflicted with the national-level, efficiency-oriented framing of the wastewater system as homogenous, without regard to place-specific differences. The research findings suggest that a distinct characteristic of urban-level governance is concern for place-specific development; this concern can be transformative because it leads to ongoing reinterpretation of traditional boundaries and dependencies between large-scale systems and local contexts.  相似文献   
962.
Healthy, fertile soil is the material of life itself. It is chemically, biologically and physically structured to support the growth of healthy, environmentally sustainable foods. Recent years have seen a resurgent focus on soil science in Australia. Yet, the influence of soil in the politics of food systems has received comparatively little attention, despite long awareness in farming communities of how the natural world shapes farmers’ choices and possible actions. Drawing on work with SoilCare, a Landcare group with a focus on soil processes in the Northern Rivers of New South Wales, this paper explores the usefulness of approaching soil as an actor in food systems. Taking a participatory approach, and drawing on recent work on new materialisms, we argue that soil can be understood as an important ally in the struggle to shape a just and sustainable food system. While this work is intended to test this idea through a modest local case study, it may point to important new avenues for investigation in food politics.  相似文献   
963.
Oyster farmers depend on good water quality. Activities upstream from estuaries result in externalities that impact water quality. Over the last 10 years, oyster farmers have been developing estuary‐wide environmental management systems ( EMSs ) to tackle internal (i.e. industry‐related) and external (i.e. catchment) issues in N ew S outh W ales, A ustralia. Drawing on interview‐based research and document analyses, this paper shows that the process of creating an EMS for the oyster industry, as well as the creation of the EMS itself, resulted in legitimizing the industry's stewardship over the natural resource it depends on (water). For the oyster industry, this result was due to a change in the scale on which EMSs have been developed: instead of viewing issues at the individual business level, the systems expanded their viewpoint to the entire catchment, and included every oyster business in the estuary, as well as all other activities in the upper catchment. By providing a means of communicating internal efforts and with the support of local government bodies, EMSs provided a mechanism with which influence over upstream actors and activities could be exerted. We demonstrate this by using the ‘social‐ecological systems’ and ‘ ENCORE ’ frameworks, emphasizing the transitions that allowed for this change of scale to take place.  相似文献   
964.
Abstract

Mikania glomerata Sprengel, popularly known as “guaco,” is used in Brazilian folk medicine for several inflammatory and allergic conditions. Besides, the popular use “guaco” is indicated by the Brazilian Ministry of Health as a safe and effective herbal medicine. The biological activity of M. glomerata extracts is due to the presence of the coumarins, a large family of phenolic substances found in plants and is made of fused benzene and α-pyrone rings. Considering that there are few data on the biological effects of the extracts of M. glomerata, mainly in genetic level, this work aims to evaluate, in vitro, the genotoxicity and coumarin production in M. glomerata in conventional and organic growing. The data showed that the organic culture system showed double the concentration of coumarin being significantly more productive than the conventional system. Besides, the results of comet assay suggest that extracts of M. glomerata cultivated in a conventional system was genotoxic, increased DNA damage levels while the organic extracts seem to have antigenotoxic effect possibly due to the concentration of coumarins. Additional biochemical investigations are necessary to elucidate the mechanisms of action of M. glomerata extracts, which were found to have a role in protection against DNA damage.  相似文献   
965.
Abstract

Degradation of diuron [3‐(3,4‐dichlorophenyl)‐l,1‐dimethyl‐urea] by microorganisms obtained from pond water and sediment was determined under aerobic conditions. Enrichment procedures were used to isolate cultures capable of degrading the herbicide. Several mixed fungal/bacterial and mixed bacterial cultures were isolated that could degrade diuron. The mixed cultures degraded 67–99% of the added diuron forming from six to seven products which were separated via TLC. The major degradation product detected in most culture extracts was 3,4‐dichloroaniline. Other identified products formed were 3‐(3,4‐dichlorophenyl)‐1‐methylurea and 3‐(3,4‐dichlorophenyl)urea.  相似文献   
966.
2010年江苏省太湖流域主要污染物排放情况显示,太湖流域内的农村生活污水、农田径流和养殖污水是导致太湖水体富营养化的主要污染源。目前,在中国针对农村生活污水的处理技术已有一定研究。根据太湖流域农村生活污水的特点,人工湿地处理技术和稳定塘系统等新型污水处理技术具有良好的应用前景。  相似文献   
967.
Risks related to food production and consumption are not a recent phenomenon. Through agricultural practices, the transport of agricultural and food products, the processing of food, its storage, and finally the consumption of food, risks have been externalized, mediated, contested and ingested. But agrofood systems have also been paralleled by routinized practices and institutions that attempt to reduce risks and sustain trust among the many actors involved in these food regimes. However, both the (definition of) food risks and the institutions and discourses used to dispel anxiety and build trust are far from stable throughout time. In the contemporary modern world-order, food risks and the practices and institutions dealing with these risks reflect the significant transformations in the agrofood system, the changing nature of the risks involved in food production and consumption, and the modifications in scientific risk assessment and risk management. This article provides an overview of the current debates, discussions and practices on actual and potential institutional transformations that parallel the emergence, assessment and management of food risks in reflexive modernity. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
968.
It seems inevitable that the ongoing and rapid changes in the physical environment of the marine Arctic will push components of the region’s existing social-ecological systems—small and large—beyond tipping points and into new regimes. Ongoing changes include warming, freshening, acidification, and alterations to food web structure. In anticipation we pose three distinct but interrelated challenges: (1) to explore existing connectivities within components of the marine system; (2) to seek indicators (if they exist) of approaching regime change through observation and modeling; and (3) to build functional resilience into existing systems through adaptation-oriented policy and to have in hand transformative options when tipping points are crossed and new development trajectories are required. Each of the above challenges is scale dependent, and each requires a much deeper understanding than we currently have of connectivity within existing systems and their response to external forcing. Here, we argue from a global perspective the need to understand the Arctic’s role in an increasingly nonlinear world; then describe emerging evidence from new observations on the connectivity of processes and system components from the Canada Basin and subarctic seas surrounding northern North America; and finally posit an approach founded in “resilience thinking” to allow northern residents living in small coastal communities to participate in the observation, adaption and—if necessary—transformation of the social-ecological system with which they live.  相似文献   
969.
在分析现有交通规划、机动车尾气排放、交通噪声理论模型的基础上,提出了一套城市交通规划环境影响评价的实用方法,并结合北京市昌平卫星城东区的综合交通规划给出了该方法的应用案例.  相似文献   
970.
● Reducing environmental impacts through socioeconomic structural transitions. ● Simulation of looping the dynamic material cycle should be concerned. ● Transboundary effects of socioeconomic transitions need to be analyzed. ● Facilitating interregional cooperation and synergetic control mechanisms. Rapid socioeconomic development has caused numerous environmental impacts. Human production and consumption activities are the underlying drivers of resource uses, environmental emissions, and associated environmental impacts (e.g., ecosystem quality and human health). Reducing environmental impacts requires an understanding of the complex interactions between socioeconomic system and environmental system. Existing studies have explored the relationships among human society, economic system, and environmental system. However, it is unclear about the research progress in the effects of socioeconomic activities on environmental impacts and the potential directions of future research. This critical review finds that existing studies have identified critical regions, sectors, and transmission pathways for resource uses, environmental emissions, and environmental impacts from supply chain perspectives. Moreover, scholars have characterized the impacts of socioeconomic transitions on resource uses and environmental emissions. However, existing studies overlook the dynamic nature of the interconnections among human society, economic system, and environmental system. In addition, the effects of socioeconomic structural transitions on environmental impacts remain unknown. This review proposes four prospects and possible solutions that will contribute to a better understanding of the complex interactions among human society, economic system, and environmental system. They can help identify more effective solutions to reduce environmental impacts through socioeconomic transitions.  相似文献   
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