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231.
农村景观规划与生态建设 总被引:1,自引:0,他引:1
介绍了农村景观的发展与变化 ,论述了农村景观生态规划的内容与原则 ,并介绍了 5种典型的景观生态建设模式。 相似文献
232.
A comparative approach to assess drivers of success in mammalian conservation recovery programs
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Jennifer J. Crees Amy C. Collins P. J. Stephenson Helen M. R. Meredith Richard P. Young Caroline Howe Mark R. Stanley Price Samuel T. Turvey 《Conservation biology》2016,30(4):694-705
The outcomes of species recovery programs have been mixed; high‐profile population recoveries contrast with species‐level extinctions. Each conservation intervention has its own challenges, but to inform more effective management it is imperative to assess whether correlates of wider recovery program success or failure can be identified. To contribute to evidence‐based improvement of future conservation strategies, we conducted a global quantitative analysis of 48 mammalian recovery programs. We reviewed available scientific literature and conducted semistructured interviews with conservation professionals involved in different recovery programs to investigate ecological, management, and political factors associated with population recoveries or declines. Identifying and removing threats was significantly associated with increasing population trend and decreasing conservation dependence, emphasizing that populations are likely to continue to be compromised in the absence of effective threat mitigation and supporting the need for threat monitoring and adaptive management in response to new and potential threats. Lack of habitat and small population size were cited as limiting factors in 56% and 42% of recovery programs, respectively, and both were statistically associated with increased longer term dependence on conservation intervention, demonstrating the importance of increasing population numbers quickly and restoring and protecting habitat. Poor stakeholder coordination and management were also regularly cited by respondents as key weaknesses in recovery programs, indicating the importance of effective leadership and shared goals and management plans. Project outcomes were not influenced by biological or ecological variables such as body mass or habitat, which suggests that these insights into correlates of conservation success and failure are likely to be generalizable across mammals. 相似文献
233.
Eun-Hee Kim 《Journal of Environmental Economics and Management》2011,61(3):311-326
Although mandatory disclosure programs have been studied extensively, strategic voluntary environmental disclosures by firms are not well understood. We study the motivations for and impacts of firms' strategic disclosure of greenhouse gas reductions to the US government. We first model firms' joint abatement and disclosure decisions, incorporating both economic and political incentives. We then use data from the Department of Energy's Voluntary Greenhouse Gas Registry to compare reported reductions to actual emissions. We find that participants in the program engage in highly selective reporting: in the aggregate, they increase emissions over time but report reductions. In contrast, non-participants decrease emissions over time. Participants tend to be large firms facing strong regulatory pressure; pressure from environmental groups reduces the likelihood of participation, suggesting such groups viewed the program as a form of greenwash. Participating in the 1605(b) program had no significant effect on a firm's changes in carbon intensity over time. 相似文献
234.
济南某商业广场超过50000 m2的基坑采用一种改进的斜支撑支护体系进行支护,与普通斜支撑支护型式不同,该支护体系包括支护桩、斜撑、立柱与支撑桩.本文采用FLAC3D显式有限差分数值计算分析方法,并结合支护桩水平位移测斜数据,对该支护体系的变形特性进行分析研究,从中论证各支护单元在3个开挖阶段的运动学效应.研究结果表明... 相似文献
235.
Introduction
This paper investigates potential gender and age differences in conviction and crash occurrence subsequent to being directed to attend Iowa's Driver Improvement Program (DIP).Methods
Binary logit models were developed to investigate the factors that influence conviction occurrence after DIP by gender and age. Because of the low crash occurrence subsequent to DIP, association rules were applied to investigate the factors that influence crash occurrence subsequent to DIP, in lieu of econometric models.Results
There were statistical significant differences by driver gender, age, and conviction history in the likelihood of subsequent convictions. However, this paper found no association between DIP outcome, crash history, and crash occurrence.Impact on industry
Evaluating the differences in conviction and crash occurrence subsequent to DIP between female and male drivers, and among different age groups can lead to improvements of the effectiveness of DIPs and help to identify low-cost intervention measures, customized based on drivers’ gender and age, for improving driving behaviors. 相似文献236.
《Web应用开发技术》是一门实践性和综合性较强的课程,扩展性案例的选取对课程教学具有重要作用。以"登录注册系统"为例,通过不断扩展该案例的功能,把各章知识点逐步融入到扩展性案例当中,使学生对各章主要知识点的应用有一个清晰的整体认识,激发学生求知、求技、求异、求新的兴趣,实现理论与实践的统一。 相似文献
237.
以新型制造业TFT-LCD行业为背景,研究了STOP(Safety、Training、Observation、Program)安全训练观察程序在企业安全管理中的应用方法及效果。结合企业实际安全管理状况,通过引入STOP安全训练观察程序,设计出一套适用于企业的STOP行为观察卡及其使用方式,进而建立起企业自身的不安全行为数据库。实践结果显示,通过STOP行为观察卡记录数据可分析企业的突出安全问题。该方法为企业的安全管理进行大数据分析提供了良好的技术手段,在企业安全管理中具有广泛的应用前景。 相似文献
238.
239.
Drinking water quality deteriorates from treatment plant to customer taps, especially in the plumbing system. There is no direct evidence about what the differences are contributed by plumbing system. This study compared the water quality in the water main and at customer tap by preparing a sampling tap on the water main. The biomass was quantified by adenosine triphosphate (ATP) and the microbial community was profiled by 454 pyrosequencing. The results showed that in distribution pipes, biofilm contributed >94% of the total biomass, while loose deposits showed little contribution (< 2%) because of the low amount of loose deposits. The distribution of biological stable water had minor effects on the microbiocidal water quality regarding both quantity (ATP 1 ng/L vs. 1.7 ng/L) and community of the bacteria. Whereas the plumbing system has significant contribution to the increase of active biomass (1.7 ng/L vs. 2.9 ng/L) and the changes of bacterial community. The relative abundance of Sphingomonas spp. at tap (22%) was higher than that at water main (2%), while the relative abundance of Pseudomonas spp. in tap water (15%) was lower than that in the water from street water main (29%). Though only one location was prepared and studied, the present study showed that the protocol of making sampling tap on water main offered directly evidences about the impacts of plumbing system on tap water quality, which makes it possible to distinguish and study the processes in distribution system and plumbing system separately. 相似文献
240.
环境规划与城市总体规划是相互联系和渗透,同时又各有侧重,具有相对独立性的两种规划.城市总体规划的研究对象是一定时期的某城市,而环境规划则是针对“社会-经济-环境“这一大的复合生态系统;城市总体规划具有城市建设发展纲领的性质,而环境规划则更侧重于污染防治和生态保护与建设;从与可持续发展的关系来说,环境规划更侧重环境保护的重要意义,而城市总体规划则是城市建设发展的蓝图,对城市经济、社会和人口、资源、环境等都具有指导和控制作用,涉及面更广.另外,两种规划的编制、审批和管理单位也不同. 相似文献