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471.
We integrate information from several disparate data sources including agricultural statistics and remote sensing to quantify and map the distribution and dynamics of agricultural returns to land and water resources from 1996/1997 to 2000/2001 in the Murray–Darling Basin (MDB), Australia. Total profit to agriculture was estimated at AUD3.86B in 1996/1997 and AUD3.73B in 2000/2001. The mapping reveals a high spatial concentration of economic returns to land and water resources from agriculture. Dryland agriculture covers over 82% of the study area. Irrigated agriculture covers 1.7% of the land area (2000/2001) but returns one third of the total profit to agriculture. We found that around 80% of the profit to agriculture comes from just over 5% of the land area. The results from this regional scale economic mapping can inform regulatory policy and public investments in natural resource management through targeting industries and regions that provide low marginal returns to the natural resource base.  相似文献   
472.
The paper provides an account of aspects of exchange-rate economics that are of particular relevance to the resources sector. The issues discussed include exchange-rate volatility and the risk management practices used to deal with it, the role of productivity differences across countries, and the impact of a booming resources sector on the country's exchange rate. The discussion is organized around a simple stylized model that emphasizes the quantity theory of money and purchasing power parity as a long-run link between prices and exchange rates.  相似文献   
473.
On-ground natural resource management actions such as revegetation and remnant vegetation management can simultaneously affect multiple objectives including land, water and biodiversity resources. Hence, planning for the sustainable management of natural resources requires consideration of these multiple objectives. However, planning the location of management actions in the landscape often treats these objectives individually to reduce the process and spatial complexity inherent in human-modified and natural landscapes. This can be inefficient and potentially counterproductive given the linkages and trade-offs involved. We develop and apply a systematic regional planning approach to identify geographic priorities for on-ground natural resource management actions that most cost-effectively meet multiple natural resource management objectives. Our systematic regional planning approach utilises integer programming within a structured multi-criteria decision analysis framework. Intelligent siting can capitalise on the multiple benefits of on-ground actions and achieve natural resource management objectives more efficiently. The focus of this study is the human-modified landscape of the River Murray, South Australia. However, the methodology and analyses presented here can be adapted to other regions requiring more efficient and integrated planning for the management of natural resources.  相似文献   
474.
Al-Juaidi, Ahmed E., Jagath J. Kaluarachchi, and Ungtae Kim, 2010. Multi-Criteria Decision Analysis of Treated Wastewater Use for Agriculture in Water Deficit Regions. Journal of the American Water Resources Association (JAWRA) 46(2):395-411. DOI: 10.1111/j.1752-1688.2009.00409.x Abstract: Coastal regions such as the Gaza Strip of Palestine with limited freshwater supply suffer significantly due to the rapid depletion of water levels, seawater intrusion, and increased water demands. In such regions, use of treated wastewater (TWW) is a viable option if public health issues are addressed. The goal of this paper is to address the use of TWW in agriculture while considering net benefit, economic efficiency of water use (EEWU), environmental goals, and public health risks. The proposed methodology considers public health risk assessment and multi-criteria decision analysis to assess the beneficial use of TWW in agriculture. The methodology was demonstrated for the Gaza Strip. The health risk assessment suggests that increasing the elapsed time between irrigation and consumption and switching from surface to sprinkler and drip irrigation are practical measures to reduce public health risks. The optimization and decision analyses show that proper allocation of freshwater and TWW and distribution of land area by crop type can significantly increase the net benefit and EEWU. In most cases, net benefit increased by 44%, groundwater use reduced 29% while increasing the EEWU by threefold compared with the existing conditions. The multi-criteria decision analysis with weighted goal programming can develop flexible management options that considers a given decision-maker preference. When groundwater abstraction for agriculture reduced from 57 to 36 Mm3 as per decision analysis, the corresponding area below mean sea level decreased by 58% indicating significant aquifer recovery.  相似文献   
475.
基本农田保护政策的耕地保护效果评价   总被引:3,自引:0,他引:3  
为分析基本农田保护政策对耕地保护的效果,论文把目标分解为两个问题,一是基本农田保护政策的实施是否对耕地流失面积的减少产生了影响;二是如果有显著影响,效果有多大,即因基本农田保护政策的实施,耕地流失面积减少了多少。论文收集了2004-2007年的省级面版数据,分别采用了固定效应模型、随机效应和混合OLS模型加以估计,固定效应和随机效应检验结果表明,固定效应和随机效应模型均不优于混合OLS模型。在模型估计结果的基础上,论文分析了基本农田保护政策对耕地流失的影响,并计算了基本农田保护政策的耕地保护效果。分析表明:①在2004-2007年期间,基本农田保护政策的实施对于减少耕地流失面积产生了显著影响,基本农田保护率每提高1%,每省每年平均耕地流失面积约能减少364.4 hm2;②由于基本农田保护政策的实施,2004-2007年期间,全国耕地流失面积分别减少了853 445.19 hm2,847 724.91 hm2,859 559.37 hm2和857 961.26 hm2,4年合计减少耕地流失面积3 418 690.73 hm2,约为期间实际耕地流失面积3 020 769.49 hm2的1.13倍。  相似文献   
476.
20世纪70年代滞涨后,大量无法解释应对的现实问题让人们意识到,主流经济学关于人的基本假设存在不足,在经济研究中结合人的心理的探讨是必要的。为解释现实中农民工不积极申请积分制入户,文章利用二元Logistic模型对武汉市数据进行了分析,并基于行为经济学中的失望/后悔效应、牺牲陷阱、偏见与错觉理论解释了结果,提出作为户籍制度衍生的社会屏蔽,隐性户籍墙应囊括由二元户籍导致的对农民和市民在社会生活一切方面的歧视,其对农民工农转非选择的作用不仅在于这些客观歧视,还在于农民工面对歧视时的主观心理。改革开放后,我国大规模的人口流动持续至今,未来相当长的时期内还会日趋活跃,尤以农民工的流动突出,凸显农民工市民化的重要性。当前,农民工对市民化的犹豫不愿意,反映户籍改革及其配套制度的建立完善不到位,其与促进农民工市民化、城镇化、实现城乡一体化的要求尚有差距。  相似文献   
477.
Solar radiation management (SRM) has been proposed as a means of last resort against dangerous climate change. We propose a stylized model of intergenerational decision making on SRM research, greenhouse-gas abatement and SRM deployment, under uncertainties about (a) the extent of future climate damage and (b) effectiveness and potential harmful side-effects of SRM. Open-ended research may reveal either that SRM effectively reduces climate damage, or that it would cause more harm than benefits. We find that SRM research increases the likelihood of deployment (“slippery slope”), and derive conditions that it decreases abatement effort in expectation (“moral hazard”). Neither of these provides a rationale against SRM research, though. The rational decision is to perform SRM research, unless (i) discounting is hyperbolic and (ii) the absolute prudence of expected climate damage is smaller than absolute risk aversion. These results generalize to the case where SRM research also provides information on climate sensitivity.  相似文献   
478.
生态补偿是生态经济学领域的一个研究热点,研究者、决策者和实践者都将生态补偿视为应对生态系统退化的有效政策工具。围绕生态补偿的定义、补偿客体、生态补偿主体、补偿标准和方式,学术界进行了大量研究,形成了市场交易、生态经济、税收补贴和社会制度等多种生态补偿理论框架。但是,由于这些理论存在不同程度的缺陷,在实践中难以避免挤出效应、外溢效应、交易费用高等问题,也不利于协调效率、效益和公平之间的关系。构建具有普遍适用性和可操作性的生态补偿理论框架,需要研究如何将生态服务纳入经济学的总供给和总需求分析模型,提出简便易行的生态服务价值综合评估方法,统一生态服务价值与经济领域价值计量的基础,从生态、经济和社会的综合维度研究针对不同生态服务补偿机制的有效尺度。  相似文献   
479.
Summers JK  Smith LM  Case JL  Linthurst RA 《Ambio》2012,41(4):327-340
Natural ecosystems perform fundamental life-support services upon which human civilization depends. However, many people believe that nature provides these services for free and therefore, they are of little or no value. While we do not pay for them, we pay significantly for their loss in terms of wastewater treatment facilities, moratoriums on greenhouse gases, increased illnesses, reduced soil fertility and losses in those images of nature that contribute to our basic happiness. Little is understood about the well-being benefits of the natural environment and its ecosystem services. The interwoven relationship of ecosystems and human well-being is insufficiently acknowledged in the wider philosophical, social, and economic well-being literature. In this article, we discuss an approach to examine human well-being and the interactions of its four primary elements-basic human needs, economic needs, environmental needs, and subjective well-being-and ecosystem services.  相似文献   
480.
基于计量经济学理论对安全生产工作认识(二)   总被引:2,自引:0,他引:2  
安全生产监管行为必然发生成本支出,包括立法与执法成本、对企业监管行为带来的社会成本和政府干预行为产生的寻租成本等,其成本与代价之高实际难以估量。 安全生产监察执法策略,既要遵循法治的严肃性,也必须考虑到企业和公众,尤其是约束对象的反映,还要考量执行难度和行政资源支出,并能使多数人从执法和守法中受益,否则会严重影响其执行力,甚至可能成为一纸空文。置信度较低的执法活动,不但效果有限,而且可能损害政府的公信力,使“政府失灵”。 政府经常运用权力强化各类安全生产行政审批,这在加大了干预力度同时,为寻租活动创造了机会,为腐败提供了土壤,可能产生新的风险,行政许可对安全监管工作是双刃剑。 安全生产工作中,政府与企业之间呈现博弈关系。无论政府和公众,还是企业都不愿见到发生伤亡事故,安全监管部门应因势利导,充分考虑到企业利益与立场,运用灵活性的管理策略,首先要使大多数企业都能达到法规要求,其次让少数条件较差或不主动守法企业也能感到压力,甚至受到处罚,转而被迫加大投入,达到安全生产法规要求,逐渐实现“纳什均衡”,使安全生产监管成本与效益达到一种“帕累托最优”。 市场经济条件下,安全生产监管应设计为一种激励相容机制,使每个参与方在追求各自利益的同时,也能达到总体设定目标。政府安全监管主要角色之一是指导各类安全生产资源有效配置,这些激励机制包括:要求企业建立安全承诺机制;基于分离均衡机制对企业实施分级监管;在事故分析中,参照“汉德法则”,理性判定事故责任,激发企业安全生产投入的主动意识和守法自觉性等。 对安全生产监管部门建立全过程的绩效评估机制,重视安全监管工作的过程?  相似文献   
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