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51.
《Environmental Communication: A Journal of Nature and Culture》2013,7(7):864-878
ABSTRACTTo understand haze-related online communication in Southeast Asia, this exploratory study took a mixed method approach to conduct web analysis of online communication during haze crisis in Singapore, followed by textual analysis of traditional and new media content during peak days. First, web analytics showed that Singapore’s haze online communication occurred mostly on the Twitter platform with primary negative sentiments. Next, textual analysis results found that majority of traditional media-affiliated news provided informative haze reports and centered on positive measurements taken by government and authorities, similar to Public Information Model for crisis management. In comparison, haze-related new media content had diverse topics reflecting laymen’s viewpoints with critical tones and negative sentiments. News portals and blogs used two-way asymmetrical and symmetrical model for crisis management, respectively. Additionally, Social Cognitive Theory’s media diversity perspectives were applied to understand people’s media choices among traditional and new media during natural crisis with environmental influences. 相似文献
52.
《International Journal of Sustainable Engineering》2013,6(1):69-76
The coming together of a number of initiatives provided a springboard for an innovative pilot programme in education for sustainable development. For some time problem‐based learning has gathered momentum as an approach to educating professionals. More recently, there has been a burgeoning interest in inter‐disciplinary approaches to the complex societal and environmental issues that face the world as a whole. At the same time, professional engineering institutions have been reflecting on appropriate approaches to the education and development of future engineers. Building on work already undertaken by some of the authors, the Royal Academy of Engineering sponsored an inter‐disciplinary pilot programme in sustainable development for undergraduate engineers and scientists in the University of Manchester. The pilot was innovative not only in its inter‐disciplinary approach to sustainable development but also in its approach to the development of the curriculum. Inter‐disciplinary exercises were designed that enabled a contextual, active, collaborative and cumulative approach to learning. The assessment was also designed to align to the learning approach. Evaluation of the pilot programme suggests that it was well received by the students, and the post‐doctoral researchers who acted as facilitators, and also that there were gains in both understanding of the issues and also in approaches to learning. 相似文献
53.
药渣生物炭基质联合麦饭石对土壤-黑麦草体系的调控与机制 总被引:1,自引:1,他引:0
以板蓝根药渣为原料,选择300℃和500℃厌氧裂解制备2种生物炭(BC300和BC500)、BC500载Fe改性炭(FeBC500)、天然麦饭石(MFS)、BC500与MFS等质量组合[BC500∶MFS(1∶1)]、Fe-BC500与MFS等质量组合[Fe-BC500∶MFS(1∶1)]材料为钝化剂,采用室内盆栽实验和等温吸附实验,研究了其对土壤-黑麦草体系的调控效果,并通过比表面孔分布测定(BET)、扫描电镜分析(SEM)、X射线衍射(XRD)和傅里叶变换红外光谱(FTIR)探讨了其机制.结果表明,在添加量为2%(土)时,BC300、BC500、Fe-BC500、MFS、BC500∶MFS(1∶1)和Fe-BC500∶MFS(1∶1)均可显著降低(P 0. 05)黑麦草体内Cu和Cd含量以及显著增加黑麦草的生物量,且黑麦草的叶绿素含量和根系活力均可指示这一效果. BC300处理抑制黑麦草吸收Cu和Cd,增加黑麦草的生物量的效果要优于其他处理,可使黑麦草地下部分Cu和Cd含量分别减少44. 78%和63. 89%,地上部分分别减少76. 34%和53. 40%;地下部分生物量增加327. 22%,地上部分生物量增加504. 11%. Langmuir方程更好地拟合BC300、BC500和Fe-BC500的吸附效果,且对Cu的最大吸附量分别为8. 02、9. 20和8. 82 mg·g~(-1);对Cd的最大吸附量分别为7. 97、8. 51和7. 70 mg·g~(-1). Freundlich方程能更好地拟合MFS的吸附效果,对Cu和Cd的最大吸附量分别为7. 03 mg·g~(-1)和6. 10 mg·g~(-1). BC300和BC500主要通过其表面羟基、羧基、羰基和酯基,Fe-BC500主要通过其表面羟基和铁羟基,MFS主要通过其中Na Al Si3O8和Al2Si2O5(OH)4表面的硅羟基、羟基和羧基分别与Cu和Cd发生配合反应,进而达到钝化修复Cu和Cd污染土壤的效果.因此,药渣生物炭、铁改性药渣生物炭和麦饭石及其组合材料均可被用于Cu和Cd复合污染土壤修复,但修复机制不同. 相似文献
54.
自然资源产权管理和专业监管的分立可充分发挥市场作用,进一步促进简政放权,实现对山水林田湖草的综合管理,克服监管盲点,提升综合保护绩效,促进绿水青山转化为金山银山。设立专门机构开展自然资源资产管理,《生态文明体制改革总体方案》等规定了改革依据;自然资源统一确权登记试点取得积极进展,奠定了工作基础;与自然资源资产负债表、绿色GDP核算、生态文明建设目标评价考核等结合起来,促进改革的系统化和连贯化;建议在国家和省、市成立三级国有自然资源资产管理机构,在部分区域和流域派驻机构。为保障改革的实施,需界定国有自然资源资产的范围及所有权、监管权的角色和权限;改革生态补偿、排污权有偿使用、资源有偿利用等制度;明晰流域与属地的权力(利)关系;明确自然资源资产管理职责和生态环保党政同责的关系;重构环境保护税、资源税和自然资源资产使用费的关系;规定自然资源资产管理的原则、体制、制度和责任;建立自然资源资产清单、权利清单和管理信息平台;厘清各方权利边界和监管边界,建立评价考核和奖惩机制。 相似文献
55.
分析现有中药废水处理工艺及废水特点,并考虑到废水处理技术改造的要求,采用水解酸化-SBR-BAF法联合处理该中药废水,研究了SBR反应器的曝气时间、温度及原水pH值对系统处理效果的影响。系统进水ρ(COD)为1 249.4~1 444.5 mg/L、ρ(BOD5)为201.2~292.8 mg/L、ρ(SS)为208.7~310.6 mg/L、色度为70~100倍,曝气时间为14 h、温度为20℃、pH值为7时,出水ρ(COD)为123.4~140.8 mg/L、ρ(BOD5)为19.4~26.1 mg/L、ρ(SS)为32.7~60.4 mg/L、色度为36~50倍,COD、BOD5、SS的平均去除率分别达到90.3%、90.7%、81.8%,表明HAT-SBR-BAF法处理该中药废水是可行的。 相似文献
56.
This paper derives market equilibria (in demand functions and in bidding strategies) between oligopolists and oligopsonists in a market with intermediates and no competition in final markets. To the best of my knowledge, this theme has not been explored, despite two observations: Firstly, the commonly applied framework of non-competitive and competitive fringe firms has implausible properties for the limit of purely strategic players. Secondly, real world cases correspond at least potentially to such strategic interactions, e.g., non-competitive players selling and buying permits (CO2 and SO2). The major implications are that these non-competitive markets are characterized by a kind of double marginalization (on the demand and the supply side) resulting in too little trade and wrong price signals. 相似文献
57.
西北地区生态建设中退耕还林还草与农牧业经营方式的转变:—以内蒙古自治区准格尔旗为例 总被引:7,自引:0,他引:7
俞文华 《中国人口.资源与环境》2001,11(2):64-68
本文以内蒙古自治区准格尔旗为例,对当前退耕还林还草制度安排中存在的问题进行了分析,认为,西北地区退耕还林还草必须与改造长期占据主导地位的传统农牧业经营方式结合起来,才有可能取得预期的成效;中央政府除了对退耕还林还草进行直接的经济资助外,应为改造传统农牧业经营方式创造良好的外部环境。 相似文献
58.
Environmental, biological, socio-cultural and economic variations in the Himalayas have led to the evolution of diverse and unique traditional agroecosystems, crop species, and livestock, which help the traditional mountain farming societies to sustain themselves. During the recent past, as a result of rapid changes in land use caused by socio-cultural and economic changes and various environmental perturbations, the agrobiodiversity of the Central Himalayan agroecosystems has changed steadily. A recent survey conducted in 150 different villages located along an elevated transect of the Alaknanda catchment of the Central Himalaya revealed that over a period of two decades (1970–74 and 1990–94) the cultivated area under many traditional crops had declined significantly. A micro-level study carried out in 30 villages revealed that a series of changes had occurred in land use practices over a period of 25–30 years.The loss of agrobiodiversity and the changing socio-cultural and economic dimensions and their impacts on the sustainability of Himalayan agroecosystems are emerging as major causes of concern at local/regional/national scale, and appropriate options to meet these challenges are discussed in this paper. 相似文献
59.
为定量评估低影响开发(LID)技术对雨水径流污染负荷的削减率,选取嘉兴市柳岸禾丰小区作为LID小区,与其临近且下垫面类型相似的浅水湾小区作为传统小区,同步监测小区的外排水量和TP浓度,根据降水等级分异计算2个小区同等降水情景下单位面积污染负荷量,再以传统小区的单位面积污染负荷量为基准核算LID小区的雨水径流污染负荷削减率。结果表明:小雨时,LID设施可消纳其服务范围内的所有径流及所携带的污染物,污染负荷削减率达100%;当降水量增至超过LID设施功能阈值时,污染物削减率开始降低,中雨时降至67%,大雨时降至46%,年均雨水径流污染负荷削减率约为66%。整体来看,LID设施雨水径流污染负荷削减率表现出明显的降水等级差异。采用降水等级分异的方法能够减少降水等级所造成的误差,确保评估结果的精准程度,为小区LID设施建设提供可靠的决策依据。
相似文献60.
Paul E. Spector 《组织行为杂志》2012,33(2):151-152
This paper introduces a Journal of Organizational Behavior point/counterpoint exchange (this issue) that focuses on the appropriate level of aggregation primarily in the assessment of personality in general and core self‐evaluations (CSE) in particular. Gilad Chen reviews arguments for and against the higher‐order construct of CSE, offering a number of recommendations for strengthening it. Timothy Judge and John Kammeyer‐Mueller offer a defense of CSE, and then extend the discussion to the measurement of other constructs beyond the personality domain. Together these two papers provide important insights about the appropriate level of aggregation of individual measures, and situations in which higher‐order versus lower‐order measures might be preferred. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献