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51.
深圳国际低碳城应对发展面临的创新、资金筹集和合作创新等需求,构建了一体化营城的模式,通过完善低碳城管理体制,探索构建多方合作及利益共享机制;通过发挥综合运营平台优势,提供全方位、全过程的专业服务;通过推进资源、资产、资本综合管理,创新多元化的筹资机制,在低碳城建设运营中取得了良好成效,并在创新新型园区建设运营、正确处理政府和企业在发展新兴产业中的关系方面,提供了有益的借鉴。  相似文献   
52.
The electronic limit order book (LOB hereafter) has rapidly become the primary way of trading European carbon assets over the 4 years of the EU ETS programme (2008–2012). In this first attempt of examining the informational content of an electronic order book, we evidence that order flow imbalances have a moderate capacity to predict short term price changes. However, we find that both LOB slope and immediacy costs help to forecast quote improvements and volatility in the next 30 min. Further, we explain why informed trading is highly influential and show that it consists in mixing order splitting strategies and posting fleeting orders once the asymmetric information is reduced (Rosu, 2009). Overall, the consolidated status of the order book mirrors a high level of market uncertainty and a low degree of informational efficiency. In this way, strategic trading can in itself explain some of order book properties, independently of the degree of traders’ sophistication and market competition.  相似文献   
53.
研究目的:针对快速城镇化地区农户生计分化现象,以上海市青浦区为例,对不同生计策略类型农户的耕地利用集约度进行评价,并分析其影响因素,以期为改善农户土地利用行为、实现土地资源合理高效利用与农户生计可持续发展提供政策参考。研究方法:运用价值形态测度方法核算各生计类型农户的耕地利用集约度,以两水平方差成分模型确定耕地利用集约度影响因素。研究结果:(1)不同生计策略类型农户耕地利用集约度存在差异性,大小顺序依次为专业农业型、传统农业型、农业兼业型、非农兼业型,劳动集约度与资本集约度排序与之基本一致;(2)同一生计策略类型农户的耕地利用集约度存在相似性,耕地利用集约度的总变异中有24.32%是由农户生计策略类型不同而引起的,水平一中农业收入比重、农业补贴、耕地面积、地块平均离家距离、农户离集镇距离与水平二中是否兼业等是影响农户耕地利用集约度的显著因素;(3)模型拟合效果评价表明该方法具有可行性。研究结论:耕地利用集约度不仅与农户自身禀赋有关,而且受生计类型影响,政府相关部门应结合当地实际情况引导农户对这两方面进行调整或完善。  相似文献   
54.
The paradox of development vs. protection and conservation of the coasts highlights the need to determine if tourism and conservation can be compatible rather than opposite activities. We analyzed the spatial and temporal changes in vegetation cover, composition and diversity in three beaches located in the state of Veracruz (Mexico) with different levels of tourism activity (Natural, Trailer Park and Hotels). We calculated tourist density and evaluated vegetation cover, species richness and diversity and analyzed the changes before and after three holiday seasons (winter, spring and summer). The Natural site had the highest vegetation cover (42.8 m2), species richness (14) and diversity (1.50), and Trailer Park the lowest (4.9 m2, 8 species, and 0.897 respectively). The BACI (Before-After-Control-Design) analysis showed no significant differences before and after the holiday seasons. Our results show how low and medium density tourism can be compatible with the protection of beach and coastal dune vegetation.  相似文献   
55.
Soil is a natural resource essential to human welfare by virtue of its numerous crucial functions. In the past, soil has been taken for granted because of its widespread, albeit finite, availability. However, now that world's population is projected to exceed ten billion before the end of this century, soil is increasingly perceived as a precious commodity. Consequently, soil is increasingly under pressure by rich private investors and governments within the poorest countries to satisfy appetites for food production and biofuel. A case study is used to explore the plausibility of soil being considered as ‘brown gold’. Based on the comparison of land use maps, we estimated the value in terms of resource from raw material, carbon sink and virtual calories of the productive soil lost during the period 2003–2008 in the Emilia-Romagna Plain, one of the most productive areas of Italy. More than fifteen thousand hectares of cropland underwent land use change – in particular urbanization – over the 6-year period with an implied loss of crop production potential equivalent to the daily calorific requirement of more than 440,000 people. Taking into account that Italy is no longer self-sufficient in food production, such a loss appears to be strategically significant. Perhaps more importantly, urbanization and soil sealing has had negative ramifications on environmental sustainability, on both local and broad scales, with increased consumption of public funds. A logical framework of the socio-economic impact of land use change has been compiled and is presented as a possible example of a policy relevant approach to managing productive soils as a finite resource.  相似文献   
56.
Previous research has shown that afforestation of agricultural land is a relatively low-cost option compared to energy-based approaches for mitigating net carbon dioxide emissions, and that financial incentives affect landowner behavior and can be used to increase carbon sequestration on private land. In this paper we use stated preference data from private landowners in the Pacific Northwest region of the U.S. to examine the key factors affecting participation in an incentive program for carbon sequestration through afforestation. We also estimate the corresponding potential for carbon sequestration and its cost. Our results suggest that incentive payments would significantly and positively affect landowners⿿ level of enrollment in a tree planting program.  相似文献   
57.
孔海东  张培  刘兵 《技术经济》2019,35(6):99-108
通过文献调查并结合案例的描述性分析,提出数字技术时代价值网络中不同行为主体之间的赋能内涵、关键维度以及基于赋能跨层次效应的价值共创行为分析框架。将"赋能氛围""主体赋能"分别作为价值网络中赋能的宏观维度和微观维度进行概念化。界定了两个维度的关键组成要素,分别包括信息共享、开放性结构、协同规则以及主体关系、资源整合和影响。构建了赋能的跨层次效应模型,分析了赋能的宏观-微观跨层次效应及其对价值网络生态和主体价值创造的影响。  相似文献   
58.
Taxes to reduce the consumption of sugar-sweetened beverages (SSBs) such as soda drinks have been endorsed by the World Health Organization and are now in place in France, Hungary, and Mexico, and scheduled for Portugal, South Africa, and Great Britain. Such taxes have so far been impossible to enact in the United States at the state or federal level, but since 2014 seven local jurisdictions have put them in place. Three necessary conditions for local political enactment emerge from this recent experience: Democratic Party dominance, external financial support for pro-tax advocates, and a political message appropriate to the process (public health for ballot issues; budget revenue for city council votes). Roughly 40 percent of Americans live within local jurisdictions where the Democratic Party dominates, so room exists for local SSB taxes to continue spreading.  相似文献   
59.
研究目的:探讨耕作层土壤剥离再利用空间配置思路与方法,并以南昌市为例进行实证研究,为相关工作提供借鉴。研究方法:提出基于线性规划及OD成本矩阵方法的两次平衡计算的耕作层土壤剥离再利用土方空间配置思路。首先,确定剥离、覆土优先度并结合供求关系划定供需圈,在供需圈内部进行第一次调配平衡;其次,对于内部不能平衡的供需圈,进行第二次跨圈调配平衡,达到缩短运输距离,控制成本目的。研究结果:(1)南昌市耕作层剥离量能够满足覆土数量与质量的需求;(2)空间配置结果共划定18个供需圈,供需圈内土方调配加权平均运输距离为6 682 m,小于期望值10 km,满足项目实施要求;(3)共有15个供需圈存在土方量不平衡问题,跨圈调配的距离平均为72 071 m,满足短距离运输的要求。研究结论:以耕作层土壤剥离、覆土优先度及供求关系为基础划定供需圈,基于线性规划及OD成本矩阵的两次平衡计算的空间配置思路与方法,可以优化运输距离,减少运输成本,提高项目实施效益。本文提出的空间配置思路可以为耕作层剥离再利用工程的顺利实施提供理论与方法借鉴。  相似文献   
60.
Mountain economies will have to play a central role in attaining the global pursuit of green economic growth as crucial bearers of ecosystems goods and services. However, these economies are not adequately represented in the development policy debates in spite of their fundamental importance towards global sustainable development. This study examines the inter relationships between energy consumption, output and carbon emissions in a developing mountainous economy using an augmented Vector Autoregression model. Time-series data over the period 1975–2013 is studied applying a multivariate framework using population and gross fixed capital formation as additional variables for Nepal. Testing for Granger causality between integrated variables based on asymptotic theory reveals a long-run unidirectional Granger causality running from GDP to energy consumption, and a unidirectional Granger causality running from carbon emissions to GDP. We suggest that the government of Nepal can address energy poverty by accelerating the adoption energy conservation policies such as rationing energy consumption and energy efficiency improvements to narrow the energy supply-demand gap. The opportunity to promote the uptake of decentralised off-grid renewable technologies in remote areas and the large scale development of hydropower at the national level also needs to be prioritized. Our results remain robust across different estimators and contributes to an emerging literature on the nexus relationships between energy consumption, income and carbon emissions in mountainous developing economies.  相似文献   
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