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91.
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   
92.
藉由"微媒介",网络段子作为新媒体写作家族的成员,因其短小精悍、发表无限制、娱乐性强的特征,契合了当下快节奏的生活,迅速形成全民写作热潮。它直面现实,消解权威,颠覆传统,调侃生活,娱乐大众,成为微传播时代大众精神消费的狂欢。  相似文献   
93.
94.
This paper studies the pro‐poor bias of trade policy in India by estimating the household welfare effects of removing the current protection structure. The elimination of a pro‐poor trade policy is expected to have a negative differential welfare effect at the low end of the distribution. The paper first constructs trade restrictiveness indexes for household consumption items and industries using both tariffs and non‐tariff barriers. The results indicate that Indian trade policy is regressive through the expenditure channel as it disproportionately raises the cost of consumption for poorer households, while it is progressive through the earnings channel. Based on the net welfare effects, the elimination of the current trade protection structure is estimated to reduce inequality. These results indicate that a trade policy that is progressive through the earnings channel may induce a price effect that is regressive through the expenditure channel.  相似文献   
95.
The German government has committed to substantially limiting future land consumption. Among the most prominently discussed policy instruments is the implementation of a cap & trade system for land consumption, in which a limited amount of certificates is allocated to and traded by municipalities. Since these certificates would be a prerequisite for conducting building projects, this system is expected to reduce urban sprawl and foster the efficient allocation of land consumption projects. While previous empirical studies have supported these projections, the potential fragility of a cap & trade system in the case of macroeconomic shocks has not been considered. In three laboratory experiments, we simulate the impact of economic and budgetary crises within a cap & trade scheme for land consumption. We find that a market-based system succeeds in compensating macroeconomic disturbances with only minor welfare losses. Certificate prices in auctions and trading are somewhat more volatile before shocks, yet normalize afterwards. Trading volumes and the specifics of project realizations remain largely unaffected. Unrelated to the macroeconomic shocks, auction and market prices persistently diverge, leading to income redistributions to the state. Overall, our evidence supports the introduction of a market-based certificate scheme to reduce land consumption in Germany due to its resilience against potential shocks.  相似文献   
96.
The Chinese aviation system is in a period of rapid growth, with significant growth in second tier and emerging cities. Lower density cities could be well served by regional aircraft, either regional jets or turboprops, which offer different qualities and a different future for Chinese aviation. Turboprops offer a high level of fuel efficiency compared with regional jets which may improve the cost economics for carriers and reduce the air quality and climate impacts of a growing aviation system in a region where air quality and greenhouse gas emissions are a serious concern. However, regional jets are known for their superior quality of service and faster travel speeds. We begin with a spatial analysis of existing Chinese short-haul aviation networks and find that turboprops are deployed in limited number and are dispersed throughout the country. Their limited use, however, is not because of their cost economics. For the existing regional jet network we estimate the trade space of fuel and time for the replacement of regional jets with turboprops and find that all regional jet routes in China would generate savings if replaced with turboprops. We next establish future short-haul aviation routes between new and emerging airports and estimate the likelihood that a turboprop will be used. The finding that the most viable turboprop markets are spatially dispersed through the country validates considering turboprop investment at the state-level as a component of the established Chinese aviation sustainability initiative.  相似文献   
97.
COVID-19 pandemic starting in early 2020 has greatly impacted human and industrial activities. Air transport in China shrank abruptly in February 2020, following a year-long gradual recovery. The airline companies reacted to this unprecedented event by dramatically reducing the flight volume and rearranging the aircraft types. As the first major economy that successfully controls the spread of COVID-19, China can provide a unique opportunity to quantify the medium-long impacts on the air transport industry. To quantify the corresponding changes and to elucidate the effects of COVID-19 in the wake of two major outbreaks centered in Wuhan and Beijing, we analyze twelve flight routes formed by four selected airports, using the Automatic Dependent Surveillance-Broadcast (ADS-B) data in 2019 and 2020. Our results show that the total flight volume in 2020 reduced to 67.8% of 2019 in China. The recovering time of flight volume was about 2–6 months, dependent on the severity. In order to unwind the severe challenge, airlines mainly relied on aircraft B738 and A321 between February and June in 2020 because the fuel consumption per seat of these two aircraft types is the lowest. Besides, fuel consumption and aircraft emissions are calculated according to the Base of Aircraft Data (BADA) and the International Civil Aviation Organization's Engine Emissions Databank (ICAO's EEDB). At the end of 2020, the ratios of daily fuel consumption and aircraft emissions of 2020 to 2019 rebounded to about 0.875, suggesting the domestic commercial flights were nearly fully recovered. Our results may provide practical guidance and meaningful expectation for commercial aircraft management for other countries.  相似文献   
98.
通过对我国改革开放以来GDP增速、煤炭消费增速历史数据的分析,发现不管是经济发展,还是煤炭发展过程中都存在周期性的波动变化规律。而通过对煤炭与经济波动曲线的拟合,发现煤炭与经济发展呈协同波动变化。基于以上煤炭与经济协同波动规律,对未来煤炭与经济发展走势进行了推演,发现煤炭消费增速最早要在2015年前后才能企稳提高,由此进入新一轮上升期。综合分析表明,煤炭抗波动能力较弱,未来要实现煤炭平稳发展,需根据经济发展节奏的不断变化,及时主动地调整煤炭发展步伐,从而避免因煤炭发展的冒进或硬着陆给煤炭及关联产业发展带来长时间、高强度的冲击和损害。  相似文献   
99.
On-the-go (OTG) consumption is a growing phenomenon in the food and beverage industry. Drawing on the theory of consumption values, this study is conducted to acquire a better understanding of the influence that retail-mix elements have on OTG consumption outcomes. Specifically, this study examines the role of value for money, customer service, general assortments and healthy assortments in driving intention and satisfaction related to OTG consumption. The study also assesses the conditional value generated by the consumer's health orientation, impulsiveness and perceived time pressure. Based on a sample of 433 OTG consumers, and applying multi-group structural equation modelling (SEM) and fuzzy-set qualitative comparative analysis (fsQCA), value for money was identified as the key driver of OTG consumption outcomes. Impulsiveness and time pressure are shown to increase the effects of value for money perceptions on OTG consumption intention, while health orientation enhances the relationship between customer service and satisfaction. This study contributes to the literature on OTG consumption, explains the managerial implications for retailers, and offers recommendations to target OTG consumers better.  相似文献   
100.
Plastic pollution is a global environmental crisis that poses a huge threat to the health of people and marine ecosystems worldwide. A significant source of plastic pollution is menstrual hygiene management, and an approach that can help address this crisis is the usage of washable and reusable menstrual cups. Using an extended theory of planned behavior model that includes self-identity and perceived quality, the study predicted intentions to use menstrual cups in the Philippines. Structural equation modeling results showed that perceived quality predicted attitudes towards menstrual cup usage. Moreover, attitudes, perceived behavioral control, and self-identity predicted intentions to use menstrual cups. There were also some differences in the factors and predictors of intentions between non-users and regular users of menstrual cups. Among regular users, perceived behavioral control did not predict intentions. These findings provide empirical support for the extended model, and provides insights for governments, non-government organizations, and corporations in promoting the usage of menstrual cups to address the global plastic pollution crisis.  相似文献   
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