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781.
再论循环型经济的构建   总被引:1,自引:0,他引:1  
循环型经济是实现可持续发展的重要手段,是一种体现经济系统生态化的新的经济类型.对循环型经济的历史地位与现实意义进行了简要回顾,基于对社会发展历程中经济主导要素的演替规律和环境-社会系统中两大基本矛盾的分析,阐述了经济发展的生态化与人文化走向.研究认为,由直线型经济向循环型经济转变是由工业文明时代向环境文明时代转变的需要.从物质流和能量流视角分析了循环型经济的主要特点和关键问题,指出循环型经济的关键在于“废物的再利用"成为经济系统的有机组成部分.循环型经济的实质并不在于追求物质的“封闭式"循环利用,而是强调资源利用率及利用效率的提高.探讨了在推进循环型经济发展的实践中政府、企业与公众3种行为的整合原则与方法.   相似文献   
782.
分析了COVID-19疫情初期河南省空气质量指数(AQI),并探讨了2项重要污染物(PM2.5和NO2)分布状况和变化趋势,发现疫情管控后AQI总体趋势向好,MODIS载荷反演PM2.5浓度下降了22.7%,TropOMI卫星反演NO2柱浓度同比下降61.95%,环比下降70.25%。另外,对NO2日遥感监测结果按照"前-中-后"3个时段进行周尺度归一化社会经济活动指数SSEI计算,结果显示疫情管控措施对社会经济活动有明显的抑制作用,在疫情得到基本控制后,大部分地区的工业热源企业虽已逐步有序恢复生产,但经历了缓慢的恢复过程。河南省的经济活动恢复水平在春节后第1周至第5周处于渐进式增长状态,第6周有所回落,第7周继续攀升。  相似文献   
783.
ABSTRACT

Achieving sustainable consumption and production requires a break with current practices in many sectors, including the smartphone sector. Leaders are central actors in catalysing such change by developing, implementing and promoting innovative ideas, products and practices. Not only large but also small enterprises can aspire to assume leadership for sustainability. This contribution explores the environmental, climate and social leadership of the social enterprise Fairphone that seeks to start a movement towards a more sustainable smartphone sector. Endowed with barely any structural power, it relies on other leadership types, especially entrepreneurial leadership, which is based on dialogue, persuasion and coalition-building. Small enterprises can be leaders, but pursuing a goal such as transforming the smartphone sector takes a step-by-step approach targeting different follower groups from suppliers, competitors and consumers to end-of-life processors and policymakers. Those different follower groups are susceptible to different (combinations of) leadership types.  相似文献   
784.
The ability of private conservation organizations to remain financially viable is a key factor influencing their effectiveness. One‐third of financially motivated private‐land conservation areas (PLCAs) surveyed in South Africa are unprofitable, raising questions about landowners’ abilities to effectively adapt their business models to the socioeconomic environment. In any complex system, options for later adaptation can be constrained by starting conditions (path dependence). We tested 3 hypothesized drivers of path dependence in PLCA ecotourism and hunting business models: (H1) the initial size of a PLCA limits the number of mammalian game and thereby predators that can be sustained; (H2) initial investments in infrastructure limit the ability to introduce predators; and (H3) rainfall limits game and predator abundance. We further assessed how managing for financial stability (optimized game stocking) or ecological sustainability (allowing game to fluctuate with environmental conditions) influenced the ability to overcome path dependence. A mechanistic PLCA model based on simple ecological and financial rules was run for different initial conditions and management strategies, simulating landowner options for adapting their business model annually. Despite attempts by simulated landowners to increase profits, adopted business models after 13 years were differentiated by initial land and infrastructural assets, supporting H1 and H2. A conservation organization's initial assets can cause it to become locked into a financially vulnerable business model. In our 50‐year simulation, path dependence was overcome by fewer of the landowners who facilitated natural ecological variability than those who maintained constant hunting rates and predator numbers, but the latter experienced unsustainably high game densities in low rainfall years. Management for natural variability supported long‐term ecological sustainability but not shorter term socioeconomic sustainability for PLCAs. Our findings highlight trade‐offs between ecological and economic sustainability and suggest a role for governmental support of the private conservation industry.  相似文献   
785.
786.
The unsustainable trade in wildlife is a key threat to Earth's biodiversity. Efforts to mitigate this threat have traditionally focused on regulation and enforcement, and there is a growing interest in campaigns to reduce consumer demand for wildlife products. We aimed to characterize these behavior-change campaigns and the evidence of their impacts. We searched peer-reviewed and grey literature repositories and over 200 institutional websites to retrieve information on demand-reduction campaigns. We found 236 campaigns, mainly in the grey literature. Since the 1970s, the number of campaigns increased, although for over 15% a start date could not be found. Asia was the primary focus, although at the national level the United States was where most campaigns took place. Campaigns most often focused on a single species of mammal; other vertebrates groups, with the exception of sharks, received limited attention. Many campaigns focused on broad themes, such as the wildlife trade in general or seafood. Thirty-seven percent of campaigns reported some information on their inputs, 98% on strategies, 70% on outputs, 37% on outcomes (i.e., changes in the target audience), and 9% on impacts (i.e., biological changes or threat reduction). Information on outcomes and impacts was largely anecdotal or based on research designs that are at a high risk of bias, such as pre- and postcampaign comparisons. It was unclear whether demand-reduction campaigns had direct behavioral or biological impacts. The lack of robust impact evaluation made it difficult to draw insights to inform future efforts, a crucial part of effectively addressing complex issues, such as the wildlife trade. If demand-reduction campaigns are to become a cornerstone of the efforts to mitigate the unsustainable trade in wildlife, conservationists need to adopt more rigorous impact evaluation and a more collaborative approach that fosters the sharing of data and insights.  相似文献   
787.
Social learning is crucial for local smallholder farmers in developing countries to improve their adaptive capacity and to adapt to the current and projected impacts of climate change. While it is widely acknowledged that social learning is a necessary condition for adaptation, few studies have systematically investigated under which conditions particular forms of social learning are most successful in improving adaptive capacity of the most vulnerable groups. This study aims to design, implement and evaluate a social learning configuration in a coastal community in Vietnam. We make use of various methods during four workshop-based interventions with local smallholder farmers: interviews with key farmers and commune leaders, farmer-to-farmer learning, participatory observations and focus group discussions. The methods for evaluation of social learning configuration include in-depth interviews, focus group discussions and structured survey interviews. Our findings show that the social learning configuration used in this study leads to an increased problem ownership, an enhanced knowledge-base with regard to climate change impacts and production adaptation options, improved ability to see connections and interdependencies and finally, strengthened relationships and social cohesion. The results suggest that increased social learning in the community leads to increase in adaptive capacity of smallholder farmers and improves both their economic and environmental sustainability. We discuss the key lessons for designing learning configurations that can successfully enhance adaptive capacity and smallholder farmers’ agency and responsiveness to the challenges posed by climate change impacts.  相似文献   
788.
社会保障制度和人力资本投资的关系是近年来劳动经济学中新出现的一个课题,相关研究尚不多见。以我国养老保险的“统帐结合”模式为例,分析了社会保障对人力资本投资的影响,同时结合我国劳动力市场现状,对劳动力市场分割状态下“统帐结合”模式与人力资本投资的关系进行了分析。结果表明,增加“统帐结合”模式中个人账户的比例,将激励个人进行较多的人力资本投资,但劳动力市场分割的存在削弱了这种激励作用。因此,建议:适当增加“统帐结合”模式中个人承担的比例;建立覆盖全国的社会保障体系;加快劳动力市场建设。逐步消除劳动力市场分割状态,促进全国统一的、自由竞争的劳动力市场的形成。  相似文献   
789.
预应力锚索和微型桩联合处理深基坑失稳事故   总被引:2,自引:0,他引:2  
土钉支护具有经济快捷等优点,但土钉支护单独使用也有其局限性。通过对某土钉支护深基坑在施工过程中发生支护失稳出现险情的原因进行分析,及时地设计预应力锚索和微型桩予以联合加固,有效地控制了该基坑的变形,保证了地下室施工的安全。  相似文献   
790.
社会应急动员和资源筹募是救灾的关键。为有效组织和管理社会应急资源,充分发挥其在救灾中的作用,提出构建一个社会应急资源监测系统。这个监测系统将采集社会应急资源在社会系统中的分布、消耗和补给等的状态信息,为社会应急资源的提供者、各级社会管理部门、各级应急管理机构和系统管理员提供查询、分析和决策的接口;基于监测系统提供的信息,考虑应急救援的时间要求、数量要求、价值要求、经济性要求,建立社会应急资源和物流网络的应急能力评价指标体系。研究结果表明,根据社会应急资源监测系统提供的特定灾害应急所需的社会资源的状态信息,可确定该区域社会应急资源的可满足性、可应急性及物流网络对应急需求的满足情况,得到社会应急资源参与救援的可行性。  相似文献   
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