基于引力模型的中美农产品贸易边境效应研究

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。     

Prevention versus Treatment under Precautionary Regulation: A Case Study of Groundwater Contamination under Uncertainty

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.     

Stop and Go Agricultural Policies with a Land Market

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.     

论建国以来中国共产党的农业生产力发展观

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。     

Analysis of the Trade Dispute of Chinese Agricultural Products and Its Countermeasures

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.     

On modeling incentive systems which utilize pollution charges for pollution abatement

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.     

农业价值负功能现象的探索

农业价值中普遍存在负功能的现象。其特征是:负功能与正功能互为依存、互为转化,依据不同时间、社会、自然、经济条件而变化,有的事物本身既有正功能,又不可避免地具有负功能,负功能成为事物固有功能的一部分,并对总功能产生影响。研究负功能,有利于防止、克服和转化负功能对事物价值的影响,保持农业可持续发展。     

室内空气污染及防治对策

文章通过对室内空气污染物成因的分析,指出目前室内空气主要污染物为甲醛、苯系物、氨和氡。     

基于可持续发展的河流污染价值补偿机制研究

本文依据环境经济学物质平衡理论的概念框架,以污染者付费原则的环境经济政策为指导,研究上游河流水污染引发下游污染事件所造成的经济损失成本和事故技术等级关联系数,进而提出以公平和可持续的价值补偿标准为基础的经济补偿模型及其运作机制,为环境会计的相关计量提供参考。     

农机服务规模经营对粮食生产效率的影响机理研究

依据2009—2019年全国31个省（自治区、直辖市）的省级面板数据,运用随机前沿分析方法和Tobit模型,考量农机服务规模经营对粮食生产效率的影响及其作用机理。结果显示：2009—2019年,中国粮食生产效率总体递增,但区域间发展不平衡;农机服务规模经营通过技术引入效应和劳动力替代效应提高粮食生产效率,其中,技术引入效应的发挥受限于农业研发支出水平及其增速,劳动力替代效应在农业劳动力成本高的区域发挥的影响效用更佳。鉴于此,应加快农业科技创新,发展粮食生产全程机械化服务,完善农机社会化服务体系。