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541.
恩诺沙星对土壤微生物群落代谢功能多样性的影响(Effects of Enrofloxacin on the Functional Diversity of Soil Microbial Communities) 总被引:1,自引:1,他引:0
为了评价恩诺沙星(Enrofloxacin)对土壤微生物群落的影响,借助BIOLOG检测法比较了不同浓度恩诺沙星影响下的土壤微生物的群落特征.结果表明,加药组土壤微生物的丰富度指数和多样性指数显著低于空白对照组,且药物浓度越高丰富度和多样性越小.用药后第3d、14d,恩诺沙星含量0.1~100μg·g-1使土壤微生物群落代谢功能多样性显著降低(p<0.05);第35d,恩诺沙星含量10~100μg·g-1使土壤微生物群落代谢功能多样性显著降低,随着药物作用的时间延长,药物含量0.01~1μg·g-1组土壤微生物群落代谢功能多样性与空白对照组之间的差异变小. 相似文献
542.
管网生物膜由各种活性微生物、微生物残体及有机无机杂质组成,管网生物膜的生长会导致机会致病菌寄居、管道腐蚀以及水质恶化等系列饮用水卫生问题.为研究供水管壁生物膜形成过程和附着生长活性微生物的分布特征,采用异养菌平板计数(HPC)、流式细胞术(FCM)和16S rRNA高通量测序对3种典型室内供水管材:聚氯乙烯(PVC)、无规共聚聚丙烯(PPR)、不锈钢(STS)内壁活性微生物的生长特性和群落多样性进行了分析.结果表明,PVC管壁生物量在第73 d最先达到峰值,3种管材内壁单位面积最大生物量、生物膜成熟时期生物量均呈现PVC PPR STS的规律. 3种管材表面活性细菌群落结构组成上,PVC管表面主要以硝化螺旋菌门为主,PPR和STS管以疣微菌门为主,其中STS管壁上生物膜物种丰富度最低、多样性最小,群落结构最简单. PVC和PPR管内壁表面相较STS管存在更多的蓝藻细菌和放线菌,在饮用水输配过程中更易引发饮用水嗅味问题.管材介质对管壁生物膜上微生物群落结构存在一定影响. 相似文献
543.
The present study addresses the ongoing debate concerning academic scientific productivity. Specifically, given the increasing number of collaborations in academia and the crucial role networks play in knowledge creation, we investigate the extent to which building social capital within the academic community represents a valuable resource for a scientist's knowledge‐creation process. We measure the social capital in terms of structural position within the academic collaborative network. Furthermore, we analyse the extent to which an academic scientist's research specialization and ties that cross‐community boundaries act as moderators of the aforementioned relationship. Empirical results derived from an analysis of an Italian academic community from 2001 to 2008 suggest academic scientists that build social capital by occupying central positions in the community outperform their more isolated colleagues. However, scientific productivity declines beyond a certain threshold value of centrality, hence revealing the existence of an inverted U‐shaped relationship. This relationship is negatively moderated by the extent to which an academic focuses research activities in few scientific knowledge domains, whereas it is positively moderated by the number of cross‐community ties established. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
544.
While the redevelopment of brownfield sites has been the mainstay of public agencies and private developers, this paper argues that in order to promote just redevelopment that encourages participation and targets weak market sites, a community-based approach to brownfield redevelopment should be encouraged. Furthermore, this paper maintains that community development corporations (CDCs) could be the ideal agents to spur community development and address environmental justice concerns through their increased involvement in brownfield redevelopment projects. In order to promote these positions, we first describe this new approach, which focuses on building the capacity of CDCs to meaningfully participate in brownfield redevelopment. We then offer four proposals designed to increase this capacity. We conclude with a discussion of how community-based brownfield redevelopment connects to larger issues of democratic decision-making, environmental justice, and urban revitalisation. 相似文献
545.
Kate J. Darby 《Local Environment》2013,18(8):797-814
Residents in Paso del Norte (El Paso, Texas; Sunland Park, New Mexico; and Juárez, Mexico) have been concerned about heavy metal contamination in their communities since the 1970s, when high blood lead levels were found in children living in Smeltertown – a company town for the local metals smelter. After the smelter's closure in 1999, and throughout onsite and offsite cleanup efforts, residents have continued to express concerns about these contamination issues. Using a politics of scale framework and analysing ethnographic data and government, media and scientific documents, this paper identifies a set of major disjunctures between the scales of heavy metal contamination and the scales at which that contamination is regulated. These disjunctures exacerbate regional environmental injustice by complicating public participation, neglecting vulnerability and displacing hazards to new communities. Consequently, applying a politics of scale framework to this case study highlights regulatory and policy failures to address environmental justice. 相似文献
546.
Laura Tozer 《Local Environment》2013,18(1):20-35
Climate change and sustainable development concerns have motivated some municipalities in Canada to develop community energy plans, which focus on energy needs at the local level for the development of efficient, economical and environmental energy systems. Five Canadian cities that were early adopters of community energy planning principles were studied to assess whether implementation has occurred and what barriers have been experienced. The cities achieved success in the implementation of energy management in municipal operations despite barriers in jurisdiction, perception of cost, communication and capacity, but energy management in the community had not been fully implemented and long-term changes were not prevalent. While reductions were made in the greenhouse gas (GHG) emissions produced by municipal operations, the community's overall GHG emissions were not significantly reduced. Long-term impacts on a city's function and growth will be key if community energy planning is to significantly impact community-wide GHG emissions and energy use. 相似文献
547.
With energy crises looming, conflicts over resource extraction and production are on the rise. For communities lacking voice to participate in these conflicts, community-based organisations and local non-governmental organisations help to unite, communicate, and negotiate with other stakeholders. In this paper we compare two cases that demonstrate the roles of organisations in providing voice to citizenry impacted by environmental justice issues. We use Senecah's concept of Trinity of Voice for the purposes of evaluation. These cases provide contrasting examples of how local/regional organisations chose to either expand their organisation's mission to intervene or stick to a strict reading of their mission thus excluding involvement. In both examples we found that organisational involvement, or lack thereof, influenced how citizens were involved in decision-making with one case leading to legislation protecting property owners from industrial activities, and the other leading to a lack of effective involvement and negatively impacted citizens. 相似文献
548.
Patricia Widener 《Local Environment》2013,18(7):834-851
This article examines the relevance of environmental justice (EJ) and climate change debates as points of articulation and mobilisation among community groups responding to a proposed refinery. It then compares media coverage of the refinery project, a bi-national pipeline and other energy and climate-related news events. The analytical frame joins the EJ paradigm with citizen mobilisation on issues of climate change and energy projects that emit greenhouse gases and that discourage development of renewable sources. Data were collected and analysed from websites, public message boards and media documents. Findings indicate that a community-based anti-refinery campaign combined local EJ struggles with climate activism, while challenging fossil fuel dependencies and calling for renewable regional energy. A climate justice community formed – yet their voices were in their blogs and websites, not in local or national media. 相似文献
549.
This article explores community-awareness perspectives and actions towards dioxin-related health exposure in Paritutu Community, New Plymouth, New Zealand. The actions are analysed through media reports, covering a 10-year period from 1998 to 2008. Since 1964, Paritutu Community residents have expressed concern about increased morbidity associated with dioxin contamination from a nearby agrichemical plant. Upon investigation, official agencies were at first unable to verify a causal link between dioxin and morbidity, precipitating community activism and increasing public pressure on relevant authorities. Residents played a major role in alleviating further damage to their community by analysing and evaluating data and providing information that ultimately resulted in both official recognition of their environmental health risk and preventative strategies to alleviate their morbidity. This article backgrounds the Paritutu Community Epidemiology approach and evaluates stages in how the Paritutu Community overcame indifference and lack of precaution and exerted influence leading to the removal of the source of contamination and positive policy changes in public health including the setting up of ameliorative health services for affected people. The findings of this research support theories of popular, lay, community and worker epidemiology. 相似文献
550.
Lucie Middlemiss 《Local Environment》2013,18(3):265-280
There has been increased interest in the role of community-based action in promoting sustainable lifestyles in recent years, but relatively limited evidence on the effects of such activity on participants' behaviours. In this paper, I present an evaluation of the effects of community-based action for sustainability on participants' lifestyles. I draw on extensive qualitative research to assess how much change participants of community sustainability projects report, what kinds of participants these projects attract and how the circumstances of these projects affect the changes that participants make. The main findings are that these initiatives have different effects on different people. Those who are new to sustainability and who are actively involved in cohesive groups, which are specifically targeting their lifestyles, are more likely to report substantial changes. I present a model to explain what change occurs, for which types of participants, in what circumstances as a result of community-based action. 相似文献