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641.

生态环境管控单元是实施生态环境分区管控的重要基础,科学合理划定及更新生态环境管控单元是完善“三线一单”生态环境分区管控制度的关键技术难点。在梳理全国各省(区、市)“三线一单”生态环境管控单元划定方法的基础上,以H省全省及其A市、B市、C市3个城市为例,对比分析了要素叠加并集(叠加法)和拟合行政边界阈值(拟合法)2种生态环境管控单元划定方法的结果差异性;讨论了不同自然地理条件、生态环境功能特征下2种划定方法的适用性,建议优先采用叠加法划定生态环境管控单元,并提出了不同地形区域拟合法划定阈值标准的范围与建议。以期为优化“三线一单”生态环境管控单元划定技术方法、完善生态环境分区管控制度、提升生态环境精细化管理水平和治理能力提供技术支撑。

  相似文献   
642.
突发事件应急决策模拟演练是提升参演主体应急处置能力的重要途径,该类演练的设计开发需要系统性的理论与技术进行规范和引导。从实践归纳的角度,将该类演练的设计划分为演练内容设计和演练形式开发2部分,详尽地分析演练内容设计中的4个核心要素(主题与目标、演练情景、演练任务和目标能力)和演练形式开发中的3项关键技术(控制流程、任务导入与方案输出、信息技术平台)。此外,着重介绍了突发事件应急决策模拟演练设计开发过程中容易混淆的几组概念关系,即“情景构建与应急演练的关系”、“应急预案与应急演练的关系”、“演练内容与演练形式的关系”、“演练中‘演’与‘练’的关系”。  相似文献   
643.
Reducing costs and increasing benefits for rural communities coexisting with large carnivores is necessary for conservation of jaguar (Panthera onca) and puma (Puma concolor). To design acceptable incentives, stakeholders must be involved in the process. We conducted an innovative, structured, group communication process based on a Delphi technique as a template for identifying potential incentives. Community workshops with 133 members of 7 communities and surveys with 25 multidisciplinary experts from government, nongovernmental organizations, and academia provided iterative data to design a plan of incentives through 4 rounds of discussion. The final product integrated 862 ideas into 6 types of incentives: organization of communities, mechanisms for improved dialogue, citizen technical assistance, green labeling for community products, payment for the ecosystem service of biodiversity, and an assessment of financial alternatives. We used quantitative and qualitative techniques to indicate support for decisions about the design of incentives, which reduced researcher subjectivity. The diverse incentives developed and the cooperation from multiple stakeholders resulted in an incentive plan that integrated issues of governance, equity, and social norms.  相似文献   
644.
This study analysed the importance of physical forces on land-use change, on the planning framework in a Portuguese periurban area. A temporal matrix showing the trajectories of land transformation was obtained. A multivariate redundancy analysis explored the importance of physical parameters on temporal and spatial land-use change. A content analysis on urban or municipal master plans was made framing the importance of physical parameters on the planning process. The results highlighted a consistent trajectory of profound land-use changes with distinctive trajectories, with increasingly complex patterns with a limited dependence on physical variables. The trajectories were more related to the planning framework, where political actors and planning managers seemed to be most important. A theoretical model balancing three main components – physical forces, actors, and land transformation (DFA-C model) is proposed, reflecting the informal relationships between physical parameters and actors during the planning process.  相似文献   
645.
ABSTRACT

Modern organisations are in search of initiatives which will enable them to be sustainable as well as gain a competitive advantage. Lean, Six Sigma and Green initiatives are some of the widely used tools which aid the organisation to be sustainable. Recent studies have suggested that the integration of Green and Lean Six Sigma (LSS) will create a powerful methodology and help organisations to be sustainable. Yet, many organisations have found it difficult due to the lack of a generic implementation framework, which can be used for any processes and cultural context. The purpose of this study is to answer the research question: how to implement a sustainable Green LSS initiative in the organisation. Through a critical analysis of previous literature, an implementation framework is developed and practically implemented through a case study to reduce the graphite and dust pollution in a mine in India. Within case analysis, it is conducted to develop propositions, future research directions and managerial implications. This is a first study to develop and practically test a generic implementation Green LSS framework.  相似文献   
646.
Disaster resettlement, as a mitigation and preparedness measure, entails significant economic, physical, and social impacts, which continue to challenge understanding of recovery from major events, especially regarding the extent of the context and environmental efforts to rebuild livelihoods. Based on a case study of Qinling Mountains, China, this research investigates the effects of disaster resettlement from a livelihoods perspective. Methodologically, it proposes a framework that combines the pressure–state–response framework and the sustainable livelihoods approach, and it employs a structural equation model to examine how specific factors affect disaster resettlement. The results indicate that conflicts may occur during and after resettlement owing to the difference or disparity between the concerns of resettled peasants and those of the government. Consequently, the risks related to livelihoods need to be taken seriously. Effective risk communication is critical to bridge the gap between different stakeholders. The paper concludes with some practical and policy recommendations.  相似文献   
647.
Species hybrids have long been undervalued in conservation and are often perceived as a threat to pure species. Recently, the conservation value of hybrids, especially those of natural origin, has gained recognition; however, hybrid conservation remains controversial. We reviewed hybrid management policies, including laws, regulations, and management protocols, from a variety of organizations, primarily in Canada and the United States. We found that many policies are based on limited ethical and ecological considerations and provide little opportunity for hybrid conservation. In most policies, hybrids are either unrepresented or considered a threat to conservation goals. This is problematic because our review of the hybrid conservation literature identified many ethical and ecological considerations relevant to determining the conservation value of a hybrid, all of which are management‐context specific. We also noted a lack of discussion of the ethical considerations regarding hybrid conservation. Based on these findings, we created a policy framework outlining situations in which hybrids could be eligible for conservation in Canada and the United States. The framework comprises a decision tree that helps users determine whether a hybrid should be eligible for conservation based on multiple ecological and ethical considerations. The framework may be applied to any hybrid and is flexible in that it accommodates context‐specific management by allowing different options if a hybrid is a threat to or could benefit conservation goals. The framework can inform policy makers and conservationists in decision‐making processes regarding hybrid conservation by providing a systematic set of decision criteria and guidance on additional criteria to be considered in cases of uncertainty, and it fills a policy gap that limits current hybrid management.  相似文献   
648.
Abstract

Migration process has become increasingly important in recent research on population and the environment. A majority of the existing migration and environment literature has focused on the environmental causes and determinants of migration. With the largest rural-to-urban migration flow in world history, and growing concerns about the environmental problems accompanying its fast economic development, China provides a particularly important case for migration and environment research. This paper reviews major migration theories and recent research on environmental effects on migration, with specific attention to the influences of environmental factors on rural-to-urban labor migration in China. A comprehensive multilevel conceptual framework is developed for studying the environmental causes of rural-to-urban migration in China. The effects of land resources on household labor migration decisions in rural China are explored to illustrate the application of this framework.  相似文献   
649.
Safety performance evaluation is a significant way to ensure the safety of oil and gas production plants. Various evaluation methods have been proposed to make safety evaluation more consistent and scientific. However, a major concern is that many existing safety evaluation measurements are still subjective and are not easy to obtain in a uniform way, which can be attributed to the challenges that process plants faced such as people having different knowledge levels, equipment with dispersed locations and management with many processes. This paper aims to display the impact of risk factors on system safety level in a succinct and visual way that may be expected to overcome subjective opinions from experts and provide a more pertinent and practical safety strategies. To this end, an integrated framework is developed, which considers crucial risk factors from pipeline, static equipment, dynamic equipment and management. First, Fault tree analysis (FTA) is used to explicitly determine the crucial r risk factors. Then, a novel fuzzy cognitive map cooperating with relative degree analysis model (FCM-RDA) is proposed to deal with the weigh distribution opinions. Finally, considering the oil and gas production process is a complex system, a fuzzy comprehensive evaluation (FCE) is employed to calculate the overall safety level.  相似文献   
650.
Carbon dioxide (CO2) adsorption on a standard metal-organic framework Mg2(dobdc) (Mg/DOBDC or Mg-MOF-74) and a tetraethylenepentamine (TEPA) modified Mgz(dobdc) (TEPA-Mg/DOBDC) were investigated and compared. The structural information, surface chemistry and thermal behavior of the adsorbent samples were characterized by X-ray powder diffraction (XRD), infrared spectroscopy (IR), thermogravimetric analysis (TGA) and nitrogen adsorption-desorption isotherm analysis. CO2 adsorption capacity was measured by dynamic adsorption experiments with N2-CO2 mixed gases at 60℃. Results showed that the CO2 adsorption capacity of Mg/DOBDC was significantly improved after amine modification, with an increase from 2.67 to 6.06 mmol CO2/g adsorbent. Moreover, CO2 adsorption on the TEPA-Mg/DOBDC adsorbent was promoted by water vapor, and the adsorption capacity was enhanced to 8.31 mmol CO2/g absorbent. The adsorption capacity of the TEPA-Mg/DOBDC adsorbent dropped only 3% after 5 consecutive adsorption]desorption cycles. Therefore, this kind of adsorbent can be considered as a promising material for the capture of CO2 from flue gas.  相似文献   
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