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1.
我国省域农业隐含碳排放及其驱动因素时空动态分析   总被引:1,自引:0,他引:1  
[目的]我国区域农业发展模式由于气候、环境的不同存在较大的差异,而目前针对农业隐含碳的时空动态研究较为缺乏,导致对于区域减排目标的设定缺乏全面的考虑,无法实现农业碳减排的效率性和公平性。因此,有必要分析农业隐含碳排放在不同省域的特征并分析其驱动因素,为制定体现地区间公平性且有效率的碳减排政策提供依据。[方法]文章利用2002年、2007年和2012年3年的投入产出表估算我国各省(市、区)农业隐含碳排放量,根据Kaya恒等关系将其分解为经济规模、经济结构、一般农业技术进步和低碳农业技术进步4类影响因素,并利用LMDI分解分析法对这4类影响因素的驱动力进行了分析。[结果]2002—2012年我国大部分地区农业隐含碳排放量呈上升趋势,空间上呈现从西到东、从南到北逐渐增加的分布规律,经济规模效应在各省份均呈正向驱动,且在经济发展较为迅速、经济增长后劲较强的地区驱动效应逐渐增强;经济结构效应在大部分省份呈负向驱动,且在重型工业的聚集区域负向效应逐渐增强;一般农业技术因素正向驱动区域逐渐扩散,且在农业大省正向驱动效应逐渐增强;低碳农业技术进步因素在东部发达地区负向的驱动效应较强,在西部驱动效应较弱。[结论]在未来的农业减排政策制定过程中,需要充分考虑不同地区的经济发展、产业结构、农业生产等特点。  相似文献   
2.
In the U.S., virtually no new coal-fired power plants have been built in recent years. Both industry experts and academics seem to believe that no rational firm will build a new coal-fired plant. Will such a trend continue in the future? To provide insights into this question, we investigate the optimal decision of an electricity company with an irreversible and deferrable opportunity to build either a new coal-fired or natural gas-fired power plant as its new base-load resource. According to our real option analysis, the optimal decision depends on the location. In the case of the eastern U.S., it is optimal to choose a natural gas plant if a firm is given a choice among a new natural gas plant, a new coal plant and deferring the investment. However, contrary to the common sentiment in the industry and academia, building a new coal plant in the western U.S. is still more economical than building a new natural gas plant in the absence of emission pricing. Furthermore, introducing carbon pricing to western U.S. states, as California did, can substantially increase the probability that a firm will optimally choose a natural gas plant over a coal plant.  相似文献   
3.
This paper investigates the driving factors behind the transition to a low carbon economy. Here, we offer a two-part analysis: First, we examine the factors leading to the current level of cleantech development. To do so, we examine the impact of country-level economic variables (real GDP, market return, and turnover) and country-level institutional variables on patent intensity. Results from this analysis show that cleantech patenting activity is fostered by a supportive institutional environment that promotes innovation and low-carbon development through carbon pricing policies, country-level public R&D expenditure and human capital. Second, we extend the notion of ‘path creation’ to map out different pathways for cleantech development on a country-level within a real options framework, and offer a corresponding valuation of cleantech patents. Our estimates of total wealth creation through the development of cleantech patents by 2050 range from US$10.16 to US$15.49 trillion dollars (13%–20% of the world GDP in 2017) with investment growth from US$2.93 to US$3.71 trillion (3.7%–4.7% of the world GDP in 2017). The results from our analysis suggest that market forces will drive the transition to a cleantech economy.  相似文献   
4.
Under increasing regulatory pressure to disclose environmental impacts, corporate environmental information disclosure (EID) is becoming more prevalent. However, the motives for EID and disclosure approaches (i.e., symbolic or substantive) remain controversial. Using a sample of data for 742 listed manufacturing firms in China across 3 years, we provide evidence to show that the level of EID is significantly positively associated with a firm's advertising intensity and that firms in moderately competitive industries have a higher propensity for adopting an EID‐based differentiated strategy than firms in stronger or weaker competitive industries. We also find that firms that are more sensitive to environmental issues strategically understate their environmental impact when directly facing consumers. Our results suggest that the implementation of corporate EID is strategic and that firms have strong market motives, even under regulatory pressure to demonstrate legitimacy. We discuss this study's contributions to research on EID theory and implications for strategic EID management.  相似文献   
5.
This study proposes an integrated simulation approach, which consists of a microscopic traffic simulation model, a vehicle dynamics model, and an emission estimation model, in order to estimate emissions based on more reliable vehicle performance measures. The vehicle performance measures such as engine power and engine speed significantly relate to the amount of emissions, and road curvatures and inclinations are the core inputs affecting these vehicle performance measures. Therefore, providing reliable vehicle performance measures reflecting the road geometric attributes is critical for a reliable emission estimation. This study proposes to use the microscopic traffic simulation model for generating vehicle trajectories, which is advantageous in modeling various traffic situations, and the vehicle dynamics model for producing the vehicle performance measures based on the vehicle trajectories. Finally, the outputs from the vehicle dynamics model are fed into the emission estimation model to compute emission measures. This study conducted a case-study using two road sections, one is a hypothesized road section, including various curvatures and inclinations with regular variations, and the other is a Kesselberg road section, which is an actual geometry in Bayern, Germany. The emission measures are estimated in these case-study road sections using both an existing simulation approach and the proposed integrated simulation approach. The difference between these two emission estimation approaches is discussed in terms of the emission measures, including fuel consumption, nitrogen oxides, and particulate matters.  相似文献   
6.
Product aesthetics is a powerful means for achieving competitive advantage. Yet most studies to date have focused on the role of aesthetics in shaping pre-purchase preferences and have failed to consider how product aesthetics affects post-purchase processes and consumers' usage behavior. This research focuses on the relationship between aesthetics and usage behavior in the context of durable products. Studies 1A to 1C provide evidence of a positive effect of product aesthetics on usage intensity using market data from the car and the fashion industries. Study 2 corroborates these findings and shows that the more intensive use of highly aesthetic products may lead to the acquisition of product-specific usage skills that form the basis for a cognitive lock-in. Hence, consumers are less likely to switch away from products with appealing designs, an effect that is labeled as the ‘aesthetic fidelity’ effect. Study 3 addresses an alternative explanation for the ‘aesthetic fidelity effect’ based on mood and motivation but finds that the ‘aesthetic fidelity’ effect is indeed determined by usage intensity. Finally, Study 4 identifies a boundary condition of the positive effect of product aesthetics on product usage, showing that it is limited to durable products. In sum, this research demonstrates that the effects of product aesthetics extend beyond the pre-consumption stage and have an enduring impact on people's consumption experiences.  相似文献   
7.
High-speed rail (HSR) and tourism are closely related economic activities because improved mobility is perceived to facilitate tourist behavioral changes. This study examines the influence of HSR on the travel patterns of individual tourists in Taiwan in relation to time, space and carbon emissions. A framework is first provided to discuss how changes in the speed of intercity transportation will affect visitors’ choice of the journey, behavior at destinations and trip quality. In addition, HSR is expected to influence five general aspects of travel decisions relating to mobility and trip emissions, including mode selection, travel distance, length of stay per trip, annual travel frequency and total travel days. In the example of Taiwan, information by onsite sampling of 400 domestic travelers found that HSR had a weak influence on travel distance and length of stay per trip, but was observed to facilitate extended time at each stop, a deeper engagement with the locality, and an approximate 10% reduction in transport carbon emissions through intermodal substitution. These phenomena are in line with the slow travel concept of sustainable tourism consumption.  相似文献   
8.
Although corporate environmental disclosures have been researched extensively, empirical evidence regarding the indirect impact of carbon pricing on firms' voluntary disclosures is scarce. The objective of this study is to identify the indirect impact of carbon pricing initiatives on the voluntary environmental disclosures (VEDs) of electricity generating companies, analyzed through the lens of institutional theory. This study adds to the growing literature on the determinants of VED, investigating the impact of adoption of the Global Reporting Initiative and ISO 14001 on VED. Secondary data were collected from 2015 annual reports and/or standalone sustainability reports of electricity generating companies from 53 countries around the world. Content analysis approach was adopted for measuring the extent of the quality of VED. Findings of multiple regression analysis suggest that there is an indirect institutional impact of carbon pricing on the quality of VED. This study also finds that, as the form of nongovernment guidance, the Global Reporting Initiative adoption and ISO 14001 certification also have an institutional influence on the VED. VED is also affected by company size although this study reveals no significant relationship of leverage with VED.  相似文献   
9.
研究目的:基于2007—2016年26省农业生产数据,测算"面源污染"和"碳排放"两类非期望产出下的农业环境效率,构建"耕地流转—利用规模—利用方式与利用强度—农业环境效率"的传导路径并进行计量检验。研究方法:超效率SBM模型,中介效应模型。研究结果:(1)耕地流转并未显著提高农业环境效率,但耕地利用规模对农业环境效率的影响呈倒U型;(2)耕地流转有助于扩大耕地利用规模,进而在样本中对农业环境效率呈现负向影响。与此同时,耕地流转对农业环境效率也存在正向的直接效应,正负效应基本抵消;(3)耕地利用规模主要通过改变化肥和机械投入强度进而负向影响农业环境效率。研究结论:农业环境效率受耕地流转、利用规模、利用方式和强度等多重因素影响,呈现明显的传导路径,因此,为了提高农业环境效率,在积极推行土地流转和规模化经营政策时,要注意结合地区农业生产力和地理环境,避免盲目扩大经营规模,同时鼓励规模经营主体引进农业绿色环保技术,注重农业生产资料的合理利用。  相似文献   
10.
中国耕地资源利用的碳排放时空特征及脱钩效应研究   总被引:8,自引:0,他引:8  
研究目的:揭示中国耕地资源利用的碳排放时空分异规律及其与农业经济增长之间的脱钩关系,以期为中国耕地资源低碳化利用政策的制定和推行提供参考。研究方法:IPCC碳排系数法,TAPIO脱钩分析法。研究结果:(1)中国耕地资源利用的碳排放整体上呈现增长趋势,但2010年后增速趋于下降并于2016年开始转入负增长,省际差异不断扩大的同时区域间差异趋于缩小;(2)中国耕地资源利用的碳排放强度总体上处于下降态势,省际和区域间碳排放强度的差异总体上趋于缩小;(3)中国耕地资源利用的不同碳排放源的碳排放量及增速呈现不同的时序波动特征,同时存在明显的地域差异性,其中,化肥是最主要碳排放源;(4)中国2000—2012年耕地资源利用的碳排放与农业经济增长之间呈现以"弱脱钩"为主,但2013—2017年不同省域的脱钩类型及脱钩程度趋于差异化。研究结论:中国耕地资源利用碳排放的时空分异性显著,且与农业经济增长之间不同阶段和不同省域呈现不同脱钩类型,需突出减排重点、实施差异化策略及注重绿色发展等多途径推进耕地资源低碳化利用,提高政策的精准性。  相似文献   
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