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The economic impact of climate change on Kenyan crop agriculture: A Ricardian approach 总被引：3，自引：2，他引：1
This paper measures the economic impact of climate on crops in Kenya. We use cross-sectional data on climate, hydrological, soil and household level data for a sample of 816 households. We estimate a seasonal Ricardian model to assess the impact of climate on net crop revenue per acre. The results show that climate affects crop productivity. There is a non-linear relationship between temperature and revenue on one hand and between precipitation and revenue on the other. Estimated marginal impacts suggest that global warming is harmful for crop productivity. Predictions from global circulation models confirm that global warming will have a substantial impact on net crop revenue in Kenya. The results also show that the temperature component of global warming is much more important than precipitation. Findings call for monitoring of climate change and dissemination of information to farmers to encourage adaptations to climate change. Improved management and conservation of available water resources, water harvesting and recycling of wastewater could generate water for irrigation purposes especially in the arid and semi-arid areas. 相似文献
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航空收入管理的需求修复方法 总被引：1，自引：0，他引：1
由于收入管理策略的执行和顾客行为的影响，使收入管理系统中记录的需求数据不能反映真实的需求，较好的修复这些受约束的需求将有利于航空公司更加准确的预测市场需求，制订出更加正确的策略，从而获得更多的收益。基于此，将统计中用于解决不完全数据的EM法和PD法应用到航空需求修复问题中，并通过模拟数据对两个方法进行分析说明。 相似文献
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Andrew J. Krmenec 《The Professional geographer》1991,43(1):60-67
Local governments are under pressure to develop alternative revenue sources to their already strapped property tax bases. Throughout the 1970s, municipal governments nationwide restructured their local taxes by substituing sales tax for property tax revenue. A tax accounting model identified two sources of sales-for-property tax substitution: changes in the tax rates and normal economic growth and decline. Most of the sales-for-property tax substitution experienced in Illinois city finance was attributable to economic change. The critical determinant of this substitution appreared to be the municipality's share of the regional retail market. Cities in higher density metropolitan areas were less likely to experience sales-for-property tax substitution through economic growth than those cities in lower density, less competitive environments. 相似文献
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从国库集中收付改革的内容、要求,地质勘查单位的现状出发,探讨了国库集中收付改革与深化地质勘查单位改革之间存在的问题,指出国库集中收付制度虽然能够使事业单位的财政收支得到有效监管,但因地质勘查单位具有事业与企业的双重职能,现行的国库集中收付制度不利于地勘单位的深化改革。为有效解决这一矛盾．提出了在国库单一账户体系外,建立地质勘查单位改革性基本账户的建议。 相似文献
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This article analyses the implementation of emissions trading systems (ETSs) in eight jurisdictions: the EU, Switzerland, the Regional Greenhouse Gas Initiative (RGGI) and California in the US, Québec in Canada, New Zealand, the Republic of Korea and pilot schemes in China. The article clarifies what is working, what isn’t and why, when it comes to the practice of implementing an ETS. The eight ETSs are evaluated against five main criteria: environmental effectiveness, economic efficiency, market management, revenue management and stakeholder engagement. Within each of these categories, ETS attributes ? including abatement cost, stringency of the cap, improved allocation practices over time and the trajectory of price stability ? are assessed for each system. Institutional learning, administrative prudence, appropriate carbon revenue management and stakeholder engagement are identified as key ingredients for successful ETS regimes. Recent implementation of ETSs in regions including California, Québec and South Korea indicates significant institutional learning from prior systems, especially the EU ETS, with these regions implementing more robust administrative and regulatory structures suitable for handling unique national and sub-national opportunities and constraints. The analysis also shows that there is potential for a ‘double dividend’ in emissions reductions even with a modest carbon price, provided the cap tightens over time and a portion of the auctioned revenues are reinvested in other emissions-reduction activities. Knowledge gaps exist in understanding the interaction of pricing instruments with other climate policy instruments and how governments manage these policies to achieve optimum emissions reductions with lower administrative costs.Key policy insights
Countries are learning from each other on ETS implementation.
Administrative and regulatory structures of ETS jurisdictions appear to evolve and become more robust in every ETS analysed.
A ‘double dividend’ for emissions reductions may also exist in cases where mitigation occurs as a result of the ETS policy and when auction revenues are reinvested in other emissions-reduction activities.
6.
《African Journal of Marine Science》2013,35(4):497-504
Populations of the African penguin Spheniscus demersus have decreased dramatically over the past century, due in part to competition for food with commercial fisheries, and the species is now endangered as a result. Economic arguments are used to favour fisheries over the needs of penguins, but penguins have direct value to the South African economy thanks to penguin-based tourism at several breeding colonies. We estimated the value of African penguins at the most important tourist site for African penguins: Boulders on the Cape Peninsula, South Africa. As a mainland colony close to Cape Town, Boulders is accessible to large numbers of visitors; gate revenues in 2009/2010 alone were R14.5 million (US$2 million). A zonal travel-cost analysis revealed an average consumer surplus among Cape Town residents of some R20 per visit. Penguin-based tourism thus forms an integral part of the R25 billion Western Cape tourism sector. Given that the future survival of this valuable resource is dependent, among others, on the availability of sufficient prey, competition with South Africa's purse-seine fishing fleet should be limited through management strategies that lessen the potential effects of fishing on prey available at the local scale. 相似文献
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根据税收筹划的定义、特征及产生必备的条件、税收筹划的原则来分析企业财务,总结经验,旨在抛砖引玉,唤起广大会计工作者的研究热情,使税收筹划的作用在新环境下得以充分发挥。 相似文献
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城市大型会展事件对酒店业的空间差异化影响一直是学界关注的热点。现有研究多关注某一届展会造成的短期且静态化的经济格局影响，较少关注展馆迁址所产生的长期而动态化的格局变化。因此，文章以2008年秋季广交会会展业务整体迁至琶洲为例，探究了展馆迁址对广州市域星级酒店在展会期间营收格局的空间重构，具有一定的现实意义。基于计量统计和ArcGIS平台，研究揭示了展会期间广州市域星级酒店营收格局的变化趋势及其背后逻辑。研究发现，在展馆迁址后的8年间，广交会期间的市域星级酒店：1）总体及平均营收均从“单核”转向“双核”格局，营收重心的“东延”“南拓”与展馆迁址在空间上具有相对一致性。展馆迁址改变了酒店与展会的空间距离，引发住宿需求在空间上的转移，推动市域酒店业“双核”营收格局的形成。2）营收变化率随时间呈现出由剧烈到平缓的趋势，且迁出地的变化率小于迁入地。3）迁入地酒店供给增长不足以消化会展期间巨大的住宿需求，而迁出地酒店供给格局在区域竞争中仍占优势，并且特殊的酒店购买模式使得原有住宿需求仍较多留在展馆迁出地酒店，抑制市域酒店业“双核”营收格局向以展馆新迁入地为中心的“单核”格局的演变，这使得在展馆迁址后，迁出地酒店业的总体与平均营收水平依然会保持较长时期的营收优势。 相似文献
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提出一个浮游动物昼夜垂直迁移的风险收益模型，其迁移运动的动力来自于浮游动物获取风险收益的最大值，即以尽可能小的死亡代价获取尽可能多的食物。风险收益反映浮游动物权衡死亡危险和食物摄取的结果，不仅是外界环境因子温度，食物和捕食压力的函数，也受到动物内部状态因子年龄的影响，本模型在一个简化的，典型的温带地区夏季分层水体环境中的运行结果表明，通过检测环境因子的变化，浮游动物借助于昼夜垂直迁移逃避捕食压力的同时能够实现最优的食物摄取量，同时，动物年龄不同，其迁移的形式也不同。 相似文献