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21.
本文从理论和实证研究两个角度回顾了国内外关于农机需求研究的重点文献,归纳了宏观和微观农机需求研究的共同理论基础,探讨了国内外对农机需求研究的进展,最后指出:农机需求的微观研究是目前国内农机需求研究的空白领域和值得进一步研究的、具有理论创新意义的发展方向。  相似文献   
22.
We consider the design of ambient taxes forrisk-neutral and risk-averse polluters whenpolluters and the regulatory agency haveasymmetric information about environmentalrelationships and probabilities associatedwith random events. Unlike prior work, we showthat under these conditions, optimal ambienttaxes must be firm-specific, and accompaniedby additional incentives to influencepolluters' choices of abatement techniques.  相似文献   
23.
新阶段的农业结构调整,必须适应变化了的新形势.为此,要进一步深化对农业结构调整的认识,牢固树立大农业意识、市场意识、规则意识、品牌意识、科技意识、信息意识、产业意识、工业意识、城镇意识和服务意识.  相似文献   
24.
In horticultural markets, trade barriers often apply to the processed products whereas domestic support applies to farm-produced raw commodities. Here we assess the effects of such trade barriers and domestic support by simulating the effects of policy reform on global processing tomato markets, which are faced with modest processed product tariffs and high domestic support in the European Union (EU). Both protection and EU subsidy drive down world welfare, but we find that reducing import tariffs for tomato products would yield greater effects on markets and larger welfare impacts outside Europe than would reductions in EU domestic support.  相似文献   
25.
基于引力模型的中美农产品贸易边境效应研究   总被引:1,自引:0,他引:1  
针对中美两国在农产品贸易上的新变化,应用引力模型的派生模型——边境效应引力模型对中美两国农产品贸易的流量和流向进行理论和实证研究。首先介绍了边境效应引力模型基本模型的推导过程,并引入了调整模型。然后采用1987至2005年其中5年的截面数据进行计算,结果发现:中美农产品贸易的边境效应显著存在,且呈逐年下降趋势;两国之间的农产品贸易边境效应存在流向和区域上的差异;距离的平方并不影响模型的可靠性。  相似文献   
26.
Policy discussions on agricultural pollution problems characterize prevention as more cost effective and precautionary than ex post treatment. We derive conditions under which treatment alone is more cost effective in situations involving multiple sources of emissions, multiple sites affected, and a commonly used precautionary approach to uncertainty. We also show that a greater degree of precaution can result in less reliance on prevention. An empirical case study indicates that treatment alone is the most cost-effective means of dealing with nitrate in most Maryland community water system wells. The use of leaching prevention measures is restricted to the most intensive poultry producing areas. The incremental cost of precaution is substantial.  相似文献   
27.
Stop and Go Agricultural Policies with a Land Market   总被引:1,自引:0,他引:1  
This article studies the design of farm policy in the presence of asymmetric information about farmers' productivity, a government objective to insure farmers a minimum "parity" income, an endogenous land rent, and diminishing returns on alternative (nonprogram crop) land uses. In this setting, acreage set asides are never part of an optimal farm policy, although compensated acreage limits are. When there are new farmer entrants who cannot be excluded from farm programs, optimal policy takes the form of a pure voluntary acreage limitation—or "buyout"—program in which high-cost producers participate and low-cost producers do not.  相似文献   
28.
建国以来,党的农业生产力发展观经历了探索、调整和完善的过程。第一代领导集体的农业生产力发展观偏重于农业制度的改革,进行了以集体组织下改革农业技术的实践,因忽视农民积极性和生产力系统的协调性,其实践效果差。第二、三代领导集体改变了党对农业的领导方式,高度重视农民积极性和生产力系统的协同性,形成了包括发挥农民积极性、现代工程和生物技术与传统农业技术相结合、市场农业和尊重自然规律为内容的农业生产力发展观。这是中国当代农业生产力发展的成功经验,也是党对传统农业重视天地人协调经验的继承。  相似文献   
29.
The trade dispute of agricultural products has become one of the hot issues that international community has paid close attention to for three years. This paper analyzes the current dispute situation, the characters and the causes in international export trade. It also points out how the government, enterprises and employer's organizations deal with the trade dispute of agricultural products.  相似文献   
30.
This paper examines a scheme of economic incentives for environmental protection, in which spatially differentiated pollution taxes are in use in compensating the pollution abatement costs. A simple mathematical model is described which determines an incentive system that encourages polluters to reduce the discharges to an acceptable level of ambient quality standards in a cost-effective manner. It is shown that the vector of pollution charges has to be proportional to the marginal abatement cost vector, but is smaller than the latter in magnitude. It is demonstrated that a necessary incentive effect may be achieved even if the total pollution charge is much lower (about three times) than the total abatement costs. It is also estimated how this charge incentive system reconciles conflicting criteria of cost-effectiveness and of equity. These conclusions are verified by numerical experiments with real data.  相似文献   
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