Cost Structure and Performance of Prairie Grain and Oilseed Farms

The views expressed in this paper are those of the authors and do not necessarily represent the views of Agriculture Canada     

粮堆通风过程空气焓变计算方法

粮堆通风的目的是调控粮堆内温度和含水率,这2个变量受通风所用空气的温度和湿度影响.介绍了可感受热量、水的汽化潜热、焓、比焓、比热等概念,举例说明粮食通风过程空气焓变的快速计算或从查湿表查定的方法.     

基于国家粮食安全的专项储备粮规模研究

本文在保证国家粮食安全的前提下对专项储备粮的规模进行研究。现阶段中国粮食安全的基本要素有四个：满足直接消费、间接消费、比价合理及抵御风险；粮食安全的等级介于二级与一级之间。通过对专项储备粮的功能定位，设定其目标簇中的主导目标是保证国家粮食安全；通过对专项储备粮作用的研究，设定其原则束中的基本原则为保证供求平衡。在对影响专项储备规模的基本因素和变量分析的基础上，建立了中国专项储备粮规模数学模型，并对计算出的2001年和2005—2030年的专项储备粮规模方案进行了比较分析。     

Economies of Size in Grain Farming in Saskatchewan and the Potential Impact of Rail Rationalization Proposals

This paper empirically examines the economies of size in both grain production and distribution by farm truck in Saskatchewan by using farm level data, and confirms that economies of size prevail. The examination also shows that economies of size in farm trucking reinforce the economies in production. The policy implication is such that the potential impact of an increase in rail freight rates and branch line abandonment would have a differential impact on individual producer's net income by farm size.
En utilisant les données relev'ees au niveau des fermes, ce document examine d'une façon empirique les exploitations agricoles de la Saskatchewan importantes tant du point de vue de la production céréaliere que de la distribution par camionnage et confirme que ce genre d'exploitations prédomine. L'analyse montre aussi que le camionnage par gros tonnage renforce la production. L'impact potentiel d'une augmentation des tarifs ferroviaires et I'abandon des voies d'embranchement auraient un impact sur le revenu net de chaque producteur variant selon la grandeur de son exploitation.     

Economics of Soil Compaction due to Machinery Traffic and Implications for Machinery Selection

To determine the impact of soil compaction, experiments were carried out on corn in 1976 (above-average rainfall year) and in 1977 (below-average rainfall year) with various sizes of tractors and levels of intensities (number of passes). Contrary to the common belief, larger tractors were found to cause less economic loss. These losses ranged from $400/ha for 30 kW tractors to $63/ha for 180 kW tractors in 1976. The losses (or gains in 1977) are added to the fixed, operating, and timeliness costs of machinery, which is obtained by the engineering method of finding the least-cost machinery complement. The optimum machinery sizes are then calculated and discussed for corn silage and grain corn crops, based on the typical six passes/operations under two weather conditions. Afin de déterminer les implications de la compaction du sol, des expériences ont été réalisées sur le maïs en 1976 (année avec des précipitations au-dessus de la moyenne) et en 1977 (année avec des précipitations en dessous de la moyenne). Pour réaliser ces expériences, des tracteurs de différentes grosseurs ont été utilisés à différents niveaux d'intensité (nombre de passages). Contrairement à la croyance populaire, les plus gros tracteurs ont été ceux qui ont le moins affecté le rendement des plantes. En 1976, les pertes de rendement ont varié entre $ 400/ha a avec un tracteur de 30 kW et $63/ha avec un tracteur de 180 kW. Ces pertes (ou gains comme ce fut le cas en 1977) ont été additionnées aux coûts fixes, variables ainsi qu'aux coûts dus aux retards d'exécution associés à la machinerie agricole. Finalement, les grosseurs optimales de tracteurs sont calculées et discutées pour le maïs-fourrager et le maïs-grain en se basant sur une intensité d'utilisation de six passages/opérations pour deux conditions météorologiques différentes.     

国际粮食形势及我国粮食生产潜在危机与对策

近几年世界谷物需求不断扩大,谷物库存不断减少,国际谷物价格快速上涨,粮食价格危机在全球快速蔓延。粮食出口国纷纷出台控制粮食出口政策,粮食进口国纷纷到国际市场抢购粮食。一些经济较贫困的国家因无力在国际市场抢购粮食,或无力通过财政补贴抑制国内粮食价格的快速上涨,而诱发社会动荡。尽管我国因有较充足的粮食库存,受国际粮食危机的冲击不大,但我国粮食安全仍存在潜在危机,还需采取强化耕地资源保护、水利设施和依靠科技等措施,确保我国粮食生产稳定发展和基本自给。     

Monthly Projections of National Year-Ending Grain Socks Using Quarterly and Weekly Quantity Data

A method for projecting national marketing year ending stocks of corn, sorghum, soybeans and wheat on a monthly basis using quarterly and weekly quantity data is introduced and applied to 1975-1987 data. Five years of monthly rejections for wheat and soybeans and four years of projections for corn and sorghum are compared with published USDA projections. Refinement of this technique will allow for estimation of current stocks levels or projections of ending stocks levels at any point in the marketing year.     

加入合作社对种粮大户农机投资及服务供给行为的影响分析

农业机械化水平是衡量现代农业发展程度的重要指标。以种粮大户、合作社等为代表的新型农业经营主体逐渐成为农机投资和提供农机服务的主力军。基于2018年江苏省686个种粮大户的微观调查数据,本文选用了多重跨栏模型并采用控制函数法实证检验了加入合作社对种粮大户农机投资与提供农机服务的影响。研究发现:相较于未加入合作社的种粮大户,加入合作社的种粮大户购买农机和提供农机作业服务的动机更强,户均农机作业服务供给水平更高。具体而言,加入合作社的种粮大户,其农机投资和提供农机作业服务的概率分别上升10.5和12.5个百分点,户均农机作业服务收益约增加3.382万元。由此,本文提出三点政策建议:一是引导种粮大户兼具生产性和服务性的双重功能,并鼓励合作社将种粮大户组织起来,共同开展农机服务。二是发挥合作社的组织优势,引导种粮大户投资相对短缺的农机装备。三是农机补贴向服务供给短缺的农机品种倾斜。     

Spatial Complementarity of Forests and Farms: Accounting for Ecosystem Services

Our article considers the economic contributions of forest ecosystem services, using a case study from Flores, Indonesia, in which forest protection in upstream watersheds stabilize soil and hydrological flows in downstream farms. We focus on the demand for a weak complement to the ecosystem services—farm labor—and account for spatial dependence due to economic interactions, ecosystem processes, and data integration. The estimated models have theoretically expected properties across eight different specifications. We find strong evidence that forest ecosystem services provide economically substantive benefits to local people and that these services would be substantially undervalued if spatial dependence is ignored.     

Relationships between Technical Efficiency and Financial Management for Czech Republic Farms

This paper provides the first analysis of the relationship between farm financial structure and technical efficiency in Central and Eastern European farming during the transition to a market economy. First, technical efficiency scores for a sample of Czech farms are computed with data envelopment analysis, accounting for sampling variability by using the Simar and Wilson bootstrapping procedure. The confidence intervals show that corporate livestock farms are the most homogenous in terms of technical efficiency. Second, a Tobit model is applied for the investigation of factors, including financial considerations, which influence the variation in technical efficiency. The potential endogeneity of the financial variables in the explanation of efficiency is examined, following Smith and Blundell. The Amemiya estimator is used for those cases which are revealed as endogenous. The analysis indicates substantial differences in the way in which the different management structures are treated by lenders. De novo, individual farms are subject to stringent evaluation of their loan applications, which is not the case for the successors of the former collective and state farms.     

浅谈粮食市场化与粮食市场建设

１粮食市场化的核心是建立一种新的粮食流通体制搞计划经济在理论上曾认为是社会主义制度的一大优势，在粮食问题上尤为突出。然而，当粮食不再短缺，而是供过于求的时候，这种通过分配来进行消费的方式就完全成了多余。党中央、国务院最早认识到这个问题。１９８５年，在刚刚经历了１９８４年农村首次出现卖粮难之后，国务院农村政策研究室提出了改统购为定购的思路，从此走上了粮食市场化的探索之路。１９９２年部分地区在政策上放开了粮食的购销和价格，由于当时条件仍不成熟，期间有过一些反复。真正意义上的放开是２００１年，浙江省经…     

Cost Efficiency for Alberta and Ontario Dairy Farms: An Interregional Comparison

In this study, two non-homothetic translog stochastic meta-frontier cost functions—with and without local concavity imposed—are estimated using a nonlinear maximum likelihood estimation procedure to compare the cost efficiency of Alberta and Ontario dairy farms for the period 1984–96. The resulting cost efficiency estimates are not very sensitive to whether or not curvature is imposed. In contrast, the properties of the cost and input demand functions (e.g., elasticities) are sensitive to imposition of local concavity during estimation. The implication is that if an inappropriate model that does not satisfy the properties required by the economic theory is used, the estimated input demand functions may not be reliable. Average cost efficiency for the pooled sample, with local concavity imposed, is approximately 89%. This suggests some potential for improved performance in the sector. The results also suggest that Ontario dairy farms may be more cost efficient than Alberta dairy farms, but the statistical evidence is inconclusive.     

主产区种粮成本分析与粮食安全长效机制的建立——基于湖北省荆州市2006年农户调查数据

粮食是经济社会发展的重要基础,是国家安全的重要战略物资,粮食主产区种粮农户是保证国家粮食安全的重要力量,因此如何降低种粮成本、增加种粮农民收益、提高农民种粮积极性成为建立粮食安全长效机制的重要问题。本文基于粮食主产区湖北省荆州市260份农户调查问卷,分析农户种粮成本和收益,提出粮食安全长效机制建立的建议：改善粮食生产的资源条件;控制生产资料价格;控制粮食价格;不断完善和优化粮食补贴政策。     

土地征用安置补助费计算的误区及其纠正

研究目的:探讨准确体现土地法精神的征地安置补助费计算方法.研究方法:案例解剖法.研究结果:目前多数项目征地安置补助费的计算上存在三个主要偏差:以所谓的"综合价"包含全部土地赔偿费用;按照征用土地数量而非需要安置的农业人口计算安置补助费;夸大和缩小需要安置的农业人口数量.研究结论:提出了准确理解土地法关于安置补助费计算的方式,并给出了计算公式.     

全球化背景下中国粮食供求区域均衡:对国家粮食安全的启示

中国-世界农业区域市场均衡模型(CWARMEM)是一个多市场多区域的以中国粮食问题为重点研究对象的全球农业市场政策分析模型.本文描述了CWARMEM模型的结构、特征以及建模过程,并应用该模型对全球化背景下中国粮食供求区域均衡变化趋势进行情景模拟研究,在此基础上分析了人口、资源、经济等因素变动对我国未来十年粮食安全局势的...     

工业用水量测算方法及应用

工业用水总量测算是我国实行最严格水资源管理制度的一项重要工作。为了利用现有水利统计成果对工业用水总量进行测算,文章选取了基于历史数据的预测方法和计量结合抽样的统计方法测算工业用水量,提出了"以计量结合抽样法为主,趋势外推法进行对比校核"的工业用水量测算方法。结果表明:对10万m~3以上规模的工业采用全样本计量,对规模以下的工业按一定比例进行抽样计量,测算值的相对误差可控制在10%左右。对于技术和统计投入受限的省份,可利用2011年水利普查数据和其他历史数据,适当采用趋势外推法对原有数据进行修正。