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161.
Transport users do not currently pay all costs associated with their transport activities and in particular do not pay the costs they impose on the environment. Case studies on Dublin, Amsterdam, Brussels and London have been conducted to evaluate how best to meet the requirement of the European Commission in its fair and efficient pricing aims in the transport sector, i.e. where transport users are made to pay all costs they impose. The paper presents the results of Do Nothing (DN) and Do Something (DS) scenarios for 2005 where in the latter case each transport user pays for all costs they impose including pollution, noise, accidents etc. The Dublin results, from an economics model used in the study, are examined in detail; the findings are compared with those of parallel studies conducted in the other cities to demonstrate the international relevance of this work. The comparison between the DN and DS scenarios indicates that taxes on all transport modes should be increased substantially, particularly in the morning and evening peak periods. As a result of the price increases, travel demand is reduced. A practical example where transport users could be made to pay for all their costs is road use pricing, i.e. charging individuals for the use of road space. The taxation levels suggested in the DS scenario have been used in a road use pricing trial in Dublin, the results of which were published in O'Mahony, Geraghty and Humphreys (Transportation 27, 269-283, 2000), to see if the reductions in the travel requirements of individuals proposed by the economics model are in fact true. The principles of the work presented in this paper are not only relevant to environmental impact management in the transport sector but can also be applied to other sectors. 相似文献
162.
Timothy O. Randhir John G. Lee 《Journal of the American Water Resources Association》2000,36(3):595-608
ABSTRACT: Enforceable standards play a crucial role in the design and implementation of most water quality policies. The impacts of these standards on farm income and nonpoint source (NPS) pollution can provide valuable information to develop economic policies that can improve water quality with minimal loss in income and minimal risk. This study uses an integration of nonlinear programming and a simulation model to assess the impacts of enforceable standards at technology and farm boundary levels. The results indicate that the type of pollutant regulated, enforcement type, and the level of standard had a significant impact on farm income and water quality. Choice of farm boundary standards over technology standards is dependent on the impact of the policy on other NPS pollutants, in addition to the reduction of nitrate and phosphorus pollutants. Enforcing farm boundary standards on nitrates had desirable effects on subsurface and percolate nitrogen and variance in income. Technology standards were uncertain in their effects because of the restriction on the choice of technologies available to farmers. A comparative policy analysis considering incentives, multiple impacts, transaction costs of implementation, and regional consideration is important to an effective policy design. 相似文献
163.
旅行成本法在我国应用中存在的几个问题 总被引:10,自引:1,他引:9
我国旅行成本法案例研究多数未分清旅行成本与旅游目的地本身价格的关系,推导的游憩需求曲线是旅行成本-旅游人次模型,而不是旅游目的地本身的价格-旅游人次需求曲线。文章具体说明了区域旅行成本法的基本原理及操作方法,并用乔光华文章数据重新对达里诺尔国家级自然保护区游憩价值进行计算,对旅行成本的构成等问题进行了讨论,得出其消费者剩余为0.9221×108元a/,比原研究中的0.0937×108元a/高出近10倍。认为乔光华等的研究在推断游憩需求曲线时存在方法上的问题,直接将旅行成本和时间价值作为游憩价值不符合旅行成本法的基本原理和公共物品无(或低)市场价格的经济理论。还对调整后的旅行成本数据进行了计算,得到保护区游憩价值为1.3581×108元a/。 相似文献
164.
基于生态足迹方法的中国生态可持续性分析 总被引:2,自引:1,他引:1
基于生态足迹和EMD方法,分析了中国1961~2005年生态可持续性的周期性变化,并建立具有周期性波动的非线性动力学模型,预测未来10年中国人均生态足迹和生物承载力的发展趋势。结果发现:44年来,中国人均生态足迹具有明显的4.3年、14.3年和17年3个波动周期,人均生物承载力具有明显的3.5年、8.8年、17.7年和44年4个波动周期;若未来10年中国人均生态足迹和生物承载力均延续过去44年的变化趋势,则2015年人均生态足迹、生物承载力、生态赤字将分别为1.366ghm2、1.108ghm2和0.258ghm2,人均生态足迹和生态赤字较2005年分别下降了0.27ghm2、0.441ghm2,而人均生物承载力增加了0.171ghm2。在保持经济、技术和人民生活水平稳步提高的同时,这种程度的生态超载有可能通过贸易引进生物承载力,通过技术进步、提高管理水平等增加生物承载力得到缓解。 相似文献
165.
This article proposed the concept of"climate capacity"as a way of measuring human’s adaptiveness to climate change.This article also focused on the related concepts like ecological carrying capacity,water resources carrying capacity,land carrying capacity as well as population carrying capacity.The concept of climate capacity was articulated against a background of global climate and environmental change.Essentially,China’s efforts to adapt to climate change was a matter of improving climate capacity,which is the ecosystem as well as the frequency,the intensity and the scale of human’s social activities that the climatic resources of a particular geographic area were supposed to support.The climate capacity has two components.One is the natural climate capacity,which includes temperature,sunlight,precipitation,extreme climatic events,etc.The other is the derived climate capacity,which includes water resources,land resources,ecological systems,climatic risks,etc.The climate capacity can be developed or be transferred between regions by taking engineering,technology or regime-based adaptive measures.However,these adaptive measures must be implemented under the principle of economic rationalism,ecological integrity,climate protection,and social justice.It is expected that by combining the climate capacity and its threshold value with the assessment of climate change risks,we are able to predict the optimal population carrying capacity and the scale of socioeconomic development,and furthermore,provide policy support for the socioeconomic development strategy and adaptive planning.In the regions with high climate capacity,there is a symbiotic relationship between adaptation and socioeconomic development.But,in the regions with limited climate capacity,irrational development may further damage the environment.Taking the Yangtze River delta,a region with high climate capacity,and a region of Ningxia,a region with limited climate capacity,as illustrative examples,the authors of this article analyzed the policy implications of climate capacity and further made suggestions on the problems of capacitylimited adaptation and development-driven adaptation.This article argued that the concept of climate capacity can not only be used as an analytical instrument of climate change economics,but also it can provide research support for planning regional adaptation and development with climate change impact and risk assessments. 相似文献
166.
流域生态补偿意愿的WTP与WTA差异性研究: 基于辽河中游地区居民的CVM调查 总被引:6,自引:0,他引:6
如何揭示利益相关者生态补偿的真实意愿不但是生态系统服务支付研究的难点问题,也是政府及管理部门制定生态补偿政策的关键问题。为此,论文通过对辽河流域中游地区的7个主要城市进行实地调研,采用条件价值评估法,利用同一受访者同时测量其支付意愿值(WTP)和受偿意愿值(WTA)的技术手段来检验其真实补偿意愿,研究结果显示,受访地区居民保护流域生态环境和水资源的WTP为59.39元/(人·a),WTA为248.56/(人·a);同时,针对同一受访者给出的WTP与WTA之间的较大差异性利用回归分析方法,得出其呈现不对称性的主要原因是受访者的收入水平和年龄。最后,在对研究结果进行差异性分析的基础上,提出了辽河流域生态补偿意愿差异性的研究结论和政策建议。 相似文献
167.
Linley Chiwona-Karltun Franklin Amuakwa-Mensah Caroline Wamala-Larsson Salome Amuakwa-Mensah Assem Abu Hatab Nolwandle Made Nathan Kanuma Taremwa Lemayon Melyoki Lettice Kinunda Rutashobya Thulisile Madonsela Marna Lourens Wendy Stone Alfred R. Bizoza 《Ambio》2021,50(4):794
Like the rest of the world, African countries are reeling from the health, economic and social effects of COVID-19. The continent’s governments have responded by imposing rigorous lockdowns to limit the spread of the virus. The various lockdown measures are undermining food security, because stay at home orders have among others, threatened food production for a continent that relies heavily on agriculture as the bedrock of the economy. This article draws on quantitative data collected by the GeoPoll, and, from these data, assesses the effect of concern about the local spread and economic impact of COVID-19 on food worries. Qualitative data comprising 12 countries south of the Sahara reveal that lockdowns have created anxiety over food security as a health, economic and human rights/well-being issue. By applying a probit model, we find that concern about the local spread of COVID-19 and economic impact of the virus increases the probability of food worries. Governments have responded with various efforts to support the neediest. By evaluating the various policies rolled out we advocate for a feminist economics approach that necessitates greater use of data analytics to predict the likely impacts of intended regulatory relief responses during the recovery process and post-COVID-19. 相似文献
168.
在中国农村劳动力非农就业不断加速的背景下,探讨非农就业对集体林区不同规模林农营林轮伐期的影响机制,有助于明确不同规模经营主体今后的用材林营林目标和林业在山区未来的经营发展模式,同时为林业规模化经营的合理性提供客观依据。基于劳动力转移新经济学理论,通过对浙江、江西和福建三省450户林农的调查,收集杉木营林的地块投入产出数据,在此基础上,运用Faustmann模型计算规模户与普通户的理论最优轮伐期,运用计量模型分析非农就业对集体林区不同规模林农采伐轮伐期的影响机制。研究结果发现,普通户和规模户的理论最优轮伐期趋同;非农就业的劳动力流失效应造成普通户营林的预期主伐时间显著短于理论最优轮伐期,而规模户非农就业带来的收入效应造成其采伐决策接近于理论最优轮伐期。在农村非农就业不断增加背景下,南方集体林区规模化经营的方式有利于接近最优采伐决策,更适合于培育大径材,增加林业生态和经济效益。 相似文献
169.
Philip G. King Aaron R. McGregor Justin D. Whittet 《Journal of Environmental Planning and Management》2016,59(1):98-119
This paper examines five representative sites on the California coast to illustrate a cost-effective methodology using tools and data that local decision makers can apply to analyse the economics of sea level rise (SLR) adaptation. We estimate the costs/benefits of selected responses (e.g. no action, nourishment, seawalls) to future flooding and erosion risks exacerbated by SLR. We estimate the economic value of changes to public/private property, recreational and habitat value, and beach related spending/tax revenues. Our findings indicate that the costs of SLR are significant but uneven across communities, and there is no single best strategy for adaptation. For example, Los Angeles's Venice Beach could lose $450 million in tourism revenue by 2100 with a 1.4 m SLR scenario while San Francisco's Ocean Beach would lose $80 million, but the impacts to structures could total nearly $560 million at Ocean Beach compared to $50 million at Venice Beach. 相似文献
170.
中国粮食产量变化的驱动效应及其空间分异研究 总被引:4,自引:0,他引:4
粮食安全是一个国家和地区经济和社会稳定发展的基础,而粮食产量则是衡量粮食安全的最为重要指标,研究粮食产量变化的驱动效应对于实现其持续稳定增长具有重要意义。综合考虑种植业结构、农林牧渔业结构、农业生产经济收益、农业劳动力等各因素对粮食产量的影响,从农业经济学的视角出发,构建了粮食产量分解的理论框架。基于这一框架,将粮食产量变化分解为种植经济的粮食安全效应、农业结构调整效应、农业劳动力农业经济收益效应、农业劳动力当量效应等4种。采用对数平均迪氏分解模型(LMDI)和粮食生产的空间转移系数,揭示了4种效应对1978—2014年中国粮食产量的时序变化以及2000—2013年全国31省(市、区)粮食产量的空间变化的影响程度。研究结果表明:无论从时间还是空间变化方面,农业劳动力农业经济收益效应都是驱动粮食增产的首要因素,种植经济的粮食安全效应则是抑制粮食增产的首要因素。在政府主导模式下,农业结构调整对粮食增产的负面影响较小,而在农户主导模式下,农业结构调整对粮食产量的负面影响明显增强,这一结果在粮食主产区表现尤为明显。1978—2014年,中国劳动力当量效应对粮食产量变化由正向驱动作用不断向负向抑制作用转变,且其对粮食增产的抑制作用不断增强,这一现象在粮食主产区表现也尤为突出。因此,为促进中国粮食产量持续增长,尤其需要发挥政府在粮食主产区农业结构调整中的主导作用,在确保农民生产粮食基本收益的基础上,加快延伸粮食生产产业链,进一步增加农民收入来源,促进劳动力资源在城乡之间的有效配置。 相似文献