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51.
This paper analyzes the relationship between the cultivated land use functions and the land rental decisions of rural households in three Dominant Functional Zones of Hubei, China. The results indicate that 41.10% of the rural households in the study areas participated in the land rental market. The land rental market in the Key Development Zone has both a higher participation rate and land rent; the Agricultural Production Zone has a higher participation rate but a lower land rent; and the land rental market in the Key Ecological Zone is underdeveloped. The difference in regional function and economic level leads to a significant difference in the spatial variation of the cultivated land use multifunction. Overall, the cultivated land function of rural households has a significant impact on their land transfer behavior. The higher the Functions of Economic Contribution, Food Production, and Pension & Employment, the more willing the rural households are to rent in the land, while the higher the Function of Inheritance and Retainment of the cultivated land use, the more likely the peasants are to retain their cultivated land resources. Furthermore, the correlation coefficient is significantly higher in the Key Development Zone than in the Key Ecological Zone.  相似文献   
52.
从智能家电待机工作状态入手,分析电器产品中参与待机工作的各部分电路原理,提出降低潜在功耗设计思路和计算方法,从家电设计研发阶段对待机功耗进行控制,同时对待机功耗精确测量方法关键点进行解读以控制低功耗测试不确定度,有助于低待机功耗设计和测量的标准化和规范化。  相似文献   
53.
本文运用IPCC的二氧化碳排放量测算方法,在省际层面测度了我国家庭部门直接能源消费碳排放,并基于扩展的STIRPAT和Kaya模型,构建家庭部门直接能源消费碳排放影响因子动态面板数据模型,对我国2003-2012年分省面板数据样本及城乡子样本进行系统GMM估计。本文研究表明,第一,我国城乡家庭部门碳排放总量和人均碳排放在近十年都呈快速上升趋势,家庭部门碳排放的空间分布具有明显的地域差异特征,高碳排放地区主要集中在东、中部地区,西部地区的碳排放水平较低;第二,城乡家庭部门生活能源消费的上期碳排放量对本期碳排放产生重要的正向影响,这反映出我国家庭部门碳排放具有显著的惯性特征和路径依赖性,是一种动态自适应机制;人口规模、居民消费水平、能源消费结构、碳排放强度、能源消费强度和城镇化因素,都对我国居民能源消费碳排放总量及人均碳排放具有显著的影响,城乡之间的家庭能源消费碳排放驱动因素存在差异。本文研究得到如下启示及政策含义:家庭部门碳减排将是一个有步骤、分区域的渐进过程,我国碳减排政策应当兼顾消费升级和碳排放的双重目标,努力构建分层次碳减排的适应性预期机制。具体而言,一方面应着眼于引导和激励居民低碳消费,缓解人口规模增加、消费水平提升和城镇化对家庭部门碳减排的压力;另一方面要通过能源价格改革、财政政策和环境规制政策等优化我国能源消费结构,不断降低煤炭消费比重,提高清洁能源的消费。同时,通过技术创新、设备改造等科技手段提高煤炭利用效率,降低碳排放强度,这些政策将更有利于城镇家庭部门碳减排。  相似文献   
54.
本文基于江苏省苏北地区灌云县和金湖县的农户调研,采用内生性处理回归模型考察政府干预下土地流转对不同类型农户收入的影响,并从农户土地和劳动力资源配置效率的角度解释农户收入变化的根源。研究结果表明,政府干预下土地流转对不同类型农户收入的影响效应有很大差异,农户土地转入后收入增加了161.2%,转出户收入并未显著增加;从农户资源配置角度考察,发现农户转入土地后农业生产效率显著提高,转出土地后农业生产率降低;农户土地转出后非农工作时间和工作报酬并未显著增加,表明转出户并未提高非农劳动力资源配置效率。同时,本文比较政府主导和农户自发两种类型农地流转对农户收入和资源配置效率的影响差异。结果发现,相对于自发土地流转的农户,政府主导下农户转入更大面积土地,并显著提高了单位面积土地生产效率和家庭收入水平;而政府干预土地转出不利于农户土地和劳动力资源配置效率及收入水平的提高。基于以上分析,本文认为政府干预降低了土地流转交易费用,有利于转入户扩大土地面积,实现规模经济效益,进而增加转入户收入;然而,政府干预下转出户资源配置面临较大约束,配置效率和收入都未能实现最大化。因此,政府在完善农地流转服务政策的同时,应当尊重农户土地流转意愿,使得农户土地流转符合家庭资源配置收入最大化目标。同时,要通过非农就业培训、发展非农经济,吸纳更多劳动力转移到非农业领域,进一步促进农村土地流转和规模经营,优化农村土地和劳动力资源配置效率,持续增加农民收入。  相似文献   
55.
Over the last 30 years, Spain has witnessed great economic growth. Nevertheless, in spite of an increasing degree of environmental concern, environmentally friendly attitudes and behaviours are still clearly below the European average. In this context, this paper analyses the impact of personal control and attitudes, and of certain socio-demographic, economic and political variables in the development of two environmentally friendly behaviours in Spain: consumption and purchase. The data were provided by a survey carried out in 2007 by the Centro de Investigaciones Sociológicas (Centre for Sociological Research) in Spain. The results show the importance of personal control, level of environmental information, political ideology, age and educational level variables to explaining the development of pro-environmental-related consumption behaviours. Personal attitudes, work situation, female gender and level of environmental information influence pro-environmental purchase behaviour in a positive way. Taking into account that personal attitudes are more determining of pro-environmental purchase than consumption behaviour, policy measures such as informal education, tax measures, social and individual norms and interpersonal and institutional trust are discussed to increase the development of pro-environmental behaviours in Spain.  相似文献   
56.
Refuse trucks play an important role in the waste collection process. Due to their typical driving cycle, these vehicles are characterized by large fuel consumption, which strongly affects the overall waste disposal costs. Hybrid hydraulic refuse vehicles offer an interesting alternative to conventional diesel trucks, because they are able to recuperate, store and reuse braking energy. However, the expected fuel savings can vary strongly depending on the driving cycle and the operational mode. Therefore, in order to assess the possible fuel savings, a typical driving cycle was measured in a conventional vehicle run by the waste authority of the City of Stuttgart, and a dynamical model of the considered vehicle was built up. Based on the measured driving cycle and the vehicle model including the hybrid powertrain components, simulations for both the conventional and the hybrid vehicle were performed. Fuel consumption results that indicate savings of about 20% are presented and analyzed in order to evaluate the benefit of hybrid hydraulic vehicles used for refuse collection.  相似文献   
57.
Grassroots environmental movements have recently started to question the focus on sustainable consumption as a main strategy to tackle climate change. They prefer to address individuals as citizens rather than as consumers, and focus on collective rather than individual change. Two prominent movements in this regard are Transition Towns and Climate Justice Action. While both movements criticise conventional approaches, they put forward entirely different strategies for what has to happen instead. Based on extensive qualitative research, this article analyses how these movements manifest themselves in Flanders (Belgium). The focus is on their different accounts of how and why collective practices have to be built, and the place they attribute to ‘the political’ in this. The analysis reveals the existence of two different forms of ecological citizenship: one communitarian, the other agonistic.  相似文献   
58.
The materiality of digital communication inflicts substantial environmental damage: the extraction of resources needed to produce digital devices; the toxicity of e-waste; and the rapidly increasing energy demands required to sustain data generated by digital communication. This damage, however, is paradoxically under-theorized in scholarship on environmental sustainability. Despite the existing critique of the “techno-fix” approach in sustainability studies, digitization – and digital communication in particular – continue to be celebrated as the tool for environmental sustainability; an approach we coin “digital solutionism.” The article presents the first systematic review of the literature to map the implicit assumptions about the relationships between digital communications and environmental sustainability, in order to examine how digital solutionism manifests, and why it persists. We propose a concept matrix that identifies the key blind spots with regards to environmental damages of the digital, and call for a paradigmatic shift in environmental sustainability studies. An agenda for future research is put forward that advocates for the following: (1) a systematic account of material damages of devices, platforms and data systems adopted into sustainability research and practice, resulting in changes in both research framing and methodological foundations; (2) a reconceptualization and denaturalization of the digital itself as a promising solution; (3) a theoretical dialogue between sustainability studies and environmental communication. (4) an expansion of environmental communication as a field, from focusing on the communication aspect of environmental change to include the environmental footprint of communication itself.  相似文献   
59.
农户兼业阶段性分化探析   总被引:3,自引:0,他引:3  
当前农户兼业的阶段性分化其本质是农户之间兼业进程的不统一,进而导致了严重的农村社会分化问题。本文利用江苏省苏北地区农户调研数据分析了当前农户兼业阶段性分化的现状及其带来的社会后果,利用似不相关双变量Probit模型分析了农户兼业阶段性分化的原因,得出了阻碍农户兼业发展的主要制约因素。结果显示,家庭人力资本稀缺是农户实现兼业生产的主要制约因素,农户无法进行非农工作主要是受到家庭人口规模小、老龄化严重的限制,这一部分农户家庭生活水平低,面临严重的"贫困陷阱"。政府直接干预土地流转使部分农户被动退出了农业生产,形式上实现了农户兼业进程的统一,但损害了农户的土地权益,造成农村土地产权不稳定,降低了农户自发性退农倾向,妨碍了土地市场的进一步发展,因此实质上对农户兼业进程起到了阻碍作用。此外,由于土地承包经营证书对承包经营权权能、地块四至等信息界定不清晰,对农户兼业进程的发展没有刺激作用。综合以上结论可知,土地产权以及农户家庭人力资本是导致当前农户阶段性分化的主要原因。政府不应对农村土地市场进行直接干预,而应通过完善农村社保体系、扶持农户非农就业、加快新一轮土地确权发证工作以促进土地市场与农户兼业进程的发展,在市场机制为主、政府调控为辅的环境下合理实现土地的集中与农业规模经营。  相似文献   
60.
基于多区域投入产出(MRIO)的中国区域居民消费碳足迹分析   总被引:5,自引:3,他引:2  
近年来,居民消费活动和环境的关系逐渐受到关注,而与温室气体排放相关的研究更是其中的热点.因此,本文采用“居民消费碳足迹”概念来定义特定居民消费活动所导致的直接和间接温室气体排放的总和,主要包括CO2、CH4、N2O3种温室气体;构建了基于环境扩展的多区域投入产出(Multiregional input-output,MRIO)模型的碳足迹核算方法,并以2007年中国8个区域为例对其居民消费碳足迹的数量、构成、分布及转移进行了分析.结果显示,2007年全国居民消费碳足迹总量达到31.74亿t(以CO2当量计).此外,碳足迹还呈现出区域差异明显、间接排放大于直接排放、城乡差距过大等特征.人均碳足迹方面,发展水平较高的京津、东部沿海地区明显高于相对滞后的西北、西南区域.研究还对碳足迹的区域分布和转移进行了深入探讨.结果发现,东北、京津、西北和西南区域转移收支为负,表示这些区域为其他区域承担的排放大于其他区域为其承担的排放;剩余的北部沿海、东部沿海、南部沿海和中部区域情况则正好相反.这些结果对现阶段中国制定具体区域消费政策或分配碳减排责任等具有参考价值;本研究的方法论也适用于研究其他环境因子及足迹因子与居民消费的关系.  相似文献   
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