Cap reform: modelling supply response subject to the land set-aside

This paper uses duality theory to develop a model of European Community agriculture. The model is used to investigate the impact of the land set-aside provision of the recent package of reforms of the Common Agricultural Policy. We assume that producers chose output and variable input levels that maximize difference between revenue and variable cost. By including first-order conditions for the allocation of land across its uses, we impose that the observed allocations are profit-maximizing allocations. To overcome the problem of incorporating many outputs into an estimable production structure, we imposed a priori the restriction that the technology was weakly separable in major categories of outputs. With this restriction, it was possible to model production decisions in stages using consistent aggregates in the latter stages.     

黑龙江省农业碳排放、科技投入与经济增长关系研究

[目的]以黑龙江省为例,首先对其农业碳排放总量进行测度,再研究农业碳排放同经济增长、科技投入之间的关系。[方法]利用1996~2013年的统计数据,从4个方面估算了黑龙江省农业碳排放量,进而采用自回归滞后分布模型(ARDL模型)对农业碳排放量、经济增长以及科技投入之间的关系进行实证分析。[结果]农业碳排放量、GDP增长和科技投入存在长期稳定关系,但长期来讲农业碳排放量增长速率远大于GDP增长速率;GDP增长对农业碳排放总量存在显著的正向影响,且长期影响程度远大于短期;科技投入对农业碳排放具有抑制作用且存在滞后效应,其中长期的抑制作用为12.4%,短期为3.9%,当滞后期为两年时,抑制作用尤为显著。[结论]经济增长会促进黑龙江省农业碳排放的增加,而科技投入则能对农业碳排放产生有效地抑制作用,因而黑龙江省可以通过增加农业科技投入来降低农业碳排放。     

黑龙江省农业科技园区评价指标体系研究

农业科技园区的迅速崛起,在提高与增强农业综合生产能力与竞争力方面发挥了重要作用。文章在黑龙江省农业科技园区发展的现状的基础上,对国内外相关文献进行了参考与研究,在此基础上对黑龙江省农业科技园区评价指标体系的原则进行了阐述,同时也对模型建立的程序进行了讨论,进而建立了黑龙江省农业科技园区评价指标体系。运用因子分析方法对收集的数据进行分析处理,并对黑龙江省农业科技园区的发展水平进行了评估。研究结果表明:黑龙江省农业科技园区的整体发展水平呈现上升趋势,园区的发展水平会随着经济、技术及农业投入等因子的增加而有所提高;但由于某一特殊时期资金投入、技术进步、产业结构、农业生产设备及农田水利发展水平等指标投入的减少,会导致农业科技园区发展停滞不前,甚至出现倒退的现象。据此,应该合理配置各项资源,来促进黑龙江省农业科技园区科学发展,以实现全省农业经济发展促进人民增收。     

PRODUCTION INTERRELATIONSHIPS IN SRI LANKAN PEASANT AGRICULTURE

Technical change and the extent to which commodity supplies and input demands are interrelated in Sri Lankan peasant agriculture are explored in this paper. Using a multiple-product dual model, a seemingly unrelated system of product supply and input demand equations is estimated for four crops and four variable inputs. Restrictions based on competitive behaviour and a twice continuously-differentiable production function are maintained in the non-linear least squares estimation. A number of important interrelationships in individual product supplies and input demands are identified, further documenting the need to account for intercommodity production relationships in econometric and simulation studies and in policy formulation. Non-joint production and Hicksneutral technical change are both rejected.     

A Cost Approach to Economic Analysis Under State-Contingent Production Uncertainty

This article explores the economics of input decision under production uncertainty. The article develops a methodology to specify and estimate cost-minimizing input decisions under a state-contingent technology. The analysis is applied to time series data on U.S. agriculture. It finds strong empirical evidence that expected output alone does not provide an appropriate representation of production uncertainty. The results provide empirical support for an output-cubical technology. This indicates that an ex post analysis of stochastic technology appears appropriate. The analysis also provides evidence that the cost of facing production risk has declined in U.S. agriculture over the last few decades.     

PRODUCTION TECHNOLOGY AND INPUT ALLOCATIONS IN SRI LANKAN MULTICROP FARMING

A primal production analysis is conducted of 182 farm households producing multiple outputs in the Sri Lankan dry zone. The approach involves systems estimation of the production functions with first-order equations for variable inputs and permits recovery of the production technology for each crop. Land and family labour are regarded as constraining inputs. Shadow prices are computed for the constraining inputs and yield important implications for increasing household profits. Evidence of global homotheticity in a subset of three inputs is found for three of the crops. Weak separability is rejected in all tested subsets except for fertiliser and chemicals used in the production of vegetables. Input demand elasticities are computed for allocations satisfying necessary and sufficient conditions for profit maximisation. Highly elastic conditional input demands and output supplies are implied.     

加快数字农业建设 为农业农村现代化增添新动能

[目的]贯彻落实党的十九大报告提出的乡村振兴战略以及习近平总书记最近提出的实施大数据战略要求。[方法]文章认为数字农业是实现这两大战略融合发展的必然要求和根本途径。数字农业将沿着数字技术产业化和农业产业数字化两条主线发展。[结果]数字技术产业化是用信息把小农户和大市场连接起来、用网络把乡村和城市连接起来开展全产业链条的信息服务,将形成市场主导的新型农业服务体系。产业数字化是把农业全过程数字化,提升农业生产的空间应变能力和生产要素的匹配使用能力,改善农业生产方式向精准农业和智慧农业方式发展,将形成政府推动的新型农业生产方式。两条主线融合到现代农业当中,必然形成数字农业经济体系,成为现代农业的实现途径和表现形式,成为数字中国和数字经济的重要组成部分。[结论]该文认为数字农业或者现代农业是必须同时包含数字和土地这两个核心要素的产业体系,论证了数字技术和现代农业的辩证关系。根据国内外实践和经验总结,初步提出了我国建设数字农业的基本思路、重点任务和工作措施。     

传统要素、创新要素与农业科技园区经济增长*——基于106个园区的实证分析

［目的］加强农业科技园区建设是我国未来农业科技创新工作的重要内容。通过理清创新类生产要素对农业园区经济增长的作用机制,提出园区吸引创新要素、提升创新能力的政策建议,为破解增长瓶颈提供参考。［方法］利用106个国家级农业科技园区2001—2016年要素投入与产出数据,估算创新要素与传统要素的产出贡献度,并分别使用年度均值和随机收取的11家分属于不同区域的园区个体数据,对东部、中部和西部园区的要素贡献度差异进行比较。［结果］三大区域创新要素产出占总产出的比重成倍高于同区域传统要素产出所占比重,对总产出的贡献显著; 西部地区创新要素投入对总产出的贡献率高于东部地区,中部地区创新要素投入对总产出的贡献率接近东部地区。［结论］以创新引领为特征的新经济增长不依赖于传统经济优势,加大创新要素投入是实现赶超、破解农业经济发展瓶颈的重要手段之一; 塑造园区成为农业科技创新平台和科技孵化培育载体,就能够通过创新要素的微观作用机制,以正外部经济效应带动农业及其周边产业快速增长。     

基于“藏粮于技”的粮食生产实施策略

粮食安全关乎民生和国家安全,"藏粮于地,藏粮于技"是维护我国粮食安全的基本战略。其中"藏粮于技"必须通过科技创新解决当前农业生产中的难题,提高粮食生产领域的科技贡献率。同时,必须前瞻性地加速数字农业建设、精准农业实践和智慧农业探索,奠定我国粮食生产领域生态智慧农业的基础。     

Estimation of Area Elasticities from a Standard Profit Function

This article demonstrates that both crop area and output elasticities can be calculated from a profit function. A Chambers/Just profit function (which includes land allocations as quasi-fixed factors) is used to derive shadow price equations for each crop area allocation. Jointly solving these shadow price equations for crop area makes it possible to calculate individual crop area elasticities. A profit function is specified to represent agricultural producers in the state of Iowa. Shadow price equations are jointly estimated with output supply and input demand equations. From these estimated equations, we derive the individual crop area response and output response to a change in prices.     

Impacts of climate change on lower Murray irrigation*

This article evaluates irrigated agriculture sector response and resultant economic impacts of climate change for a part of the Murray Darling Basin in Australia. A water balance model is used to predict reduced basin inflows for mild, moderate and severe climate change scenarios involving 1, 2 and 4°C warming, and predict 13, 38 and 63% reduced inflows. Impact on irrigated agricultural production and profitability are estimated with a mathematical programming model using a two‐stage approach that simultaneously estimates short and long‐run adjustments. The model accounts for a range of adaptive responses including: deficit irrigation, temporarily following of some areas, permanently reducing the irrigated area and changing the mix of crops. The results suggest that relatively low cost adaptation strategies are available for a moderate reduction in water availability and thus costs of such a reduction are likely to be relatively small. In more severe climate change scenarios greater costs are estimated. Adaptations predicted include a reduction in total area irrigated and investments in efficient irrigation. A shift away from perennial to annual crops is also predicted as the latter can be managed more profitably when water allocations in some years are very low.     

美国作物品种改良技术在近代中国的引进与利用--以金陵大学农学院、中央大学农学院为中心的研究

近代以来，伴随着农业的资本主义化，美国农业出现了两次技术革命。由于农业革命而产生的先进的作物改良技术对近代中国的农业产生了极为深远的影响。作为中国最早成立农科以及第一所在华注册的美国教会大学的金陵大学和当时的全国教育重镇中央大学在近代中关两国的农业科技交流与合作中处于极其重要的地位。本文即以两校农学院为中心探讨美国的农作物改良技术在近代中国的引进和利用。     

Measuring agricultural total factor productivity in China: pattern and drivers over the period of 1978‐2016

The Chinese agricultural sector has experienced a substantial increase in total output since dramatic reforms were introduced in 1978. This paper uses the index method to measure agricultural total factor productivity (TFP) for China’s crop and livestock industries, based on the gross output model from 1978 to 2016. We construct production accounts for the industries using input‐output relationships for the 26 main agricultural commodities and commodity groups, which account for over 90 per cent of the total agricultural inputs and outputs. The results show that China’s agricultural TFP grew at a rate of approximately 2.4 per cent a year before 2009, which is comparable to the main OECD countries and is double the world average. TFP growth accounts for approximately 40 per cent of output growth, suggesting that input growth was the main driver of output growth in the past. However, average productivity growth slowed down after 2009 though it has gradually recovered since 2012. The slowdown reflects the emerging challenges to existing farm production practices in Chinese agriculture, suggesting the need for further institutional reform.     

“黄箱”政策的农业增收效果:以粮食作物为例

为定量评价我国农业政策的农业增收效果,本文以粮食作物为例,借用世界银行TRI(贸易抑制指数)和NRA(名义支持率)数据库,分别在粮食作物亩均实际收益与农产品出口贸易抑制指数和农产品进口贸易抑制指数之间建立动态计量模型,采用协整分析、脉冲反应函数和方差分解分析等方法对我国"黄箱政策"的农业增收效果进行了实证分析。研究发现,我国农业自由化程度远高于高收入国家,且存有"重调产出、轻调投入"和"重经济效益、轻粮食安全"等政策倾向;生产者的"超调"行为使得粮食生产收益成倒"N"型变化;长期内"黄箱政策"并不是粮食作物增收的主要因素。     

中国农业史的起点与农业对草地农业系统的回归--有关我国农业起源的浅议

农业起源于以伏羲氏为代表的草地畜牧业时代。以籽粒生产为主导的神农时代相继发生。其间应存在过渡时期，过渡时期的长短，因地域特点而异。伏羲时代不仅体现了一种生产和生活方式，它还具有游牧民族的文化内涵。这是一种不可忽视的时空特征的地理历史现象。过去把神农氏作为华夏农业起源的象征，是囿于‘辟土殖谷日农’的华夏农耕文化的偏见，不仅抹煞了整个伏羲代表的历史阶段，也割裂了农业生态系统的整体模式，终于泛化为单一籽粒生产为主的“以粮为纲”单一农业系统，使土地利用偏颇，文化多样性受损，最终导致了生态、生产两败俱伤，形成举国为之忧虑的“三农问题”。农业的实质是自然生态系统遵循一定规律而发展的多阶段的农业化过程。目前在社会迅速发展的形势下，我们逐步从单一谷物生产的华夏农耕文化的弊端，领悟了农业生态系统的整体性，这无疑是我国农业向生态系统的回归，在我国农业中出现天、地、人和谐发展的曙光。     

基于生态系统服务改进的中国各地农业生态效率研究

[目的]为提高全国农业资源利用率,推动建立资源节约型与环境友好型的可持续"两型农业",对中国农业生态效率展开研究发现,农田生态系统服务是农业生产的重要产出,但在当前生态效率研究中未得到充分体现。文章通过量化农田生态系统服务价值,有利于权衡农产品供需关系,更好以农田生态系统给人类社会带来的福利为目标来开展农业生产。[方法]文章将生态系统服务价值作为期望产出之一,将全国划分为东部地区、东北地区、中部地区和西部地区的4个农业效率研究区域。运用非期望产出数据包络分析方法,计算2014年中国30个省(市、自治区)的农业生态效率,并分析其主要影响因素。[结果](1)中国农业生态效率整体水平良好,平均值为0.945,在空间上表现为东部东北西部中部的空间分布格局。(2)影响全国农业生态效率的关键因素为土地投入、机械投入、化肥投入和水资源投入。农业生态系统服务指标与农业生态效率呈正向相关。土地、农药、劳动力、机械、水资源、化肥、农膜和能源投入、农业产值及碳排放均与之呈负向相关。其中农药投入是最为显著的抑制因子,控制农药投入是提升全国农业效率核心因素。(3)中国农业生态效率空间分异格局是多层影响因素叠加而成,中国农业生态效率损失的原因主要在于资源要素消耗的过量与农业碳排放过多。[结论]中国农业生态效率整体上发展较好,但各省市的农业生态效率水平存在较大差异,仍有上升的空间。从投入产出冗余角度来看,目前中国农业生态效率损失的原因主要在于资源要素消耗的过量与农业碳排放过多。在发展中着重加大区域对农业土地的开发投入、推广机械科学技术、减少化肥等污染物投入与提高水资源的利用效率,发展用水技术,保障农业的可持续发展。     

战后工业化的努力:乡村工业示范的兴起和发展

乡村工业示范是抗战结束后在联合国善后救济总署资助下建立的一个农业善后项目，联合国善后救济总署倾向于使之能为善后救济生产物资，而中国人则希望由此能促进中国乡村的工业化。结果，示范组未能有效的实现生产救济物资的目标，却为乡村工业示范做了大量的准备。联总结束后示范组改为示范处，示范处则明确了促进农村生产，改善农民生活的目的，宣称不再具善后救济性质，并积极开展了以技术推广为主要内容的乡村工业示范活动。然而，由于国内政治经济形势趋于恶化，乡村工业示范事业最终黯然结束。     

The Influence of Labor Price Change on Agricultural Machinery Usage in Chinese Agriculture

The substitution between rural labor and machinery has been a key determinant of farm production, structure, and efficiency in most developed countries and is expected to play a key role in shaping the future of Chinese agriculture. Using disaggregated farm‐level data from Hebei and Shandong provinces of China, we calculated the Allen and Morishima elasticities of substitution between labor and machinery. These elasticities were based on seemingly unrelated regressions and three‐stage least squares estimates of the translog cost function and input cost share functions. In contrast to previous studies, we dissaggregate machinery inputs into three categories: large, medium, and small. In addition, the issue of endogeneity in output quantity and input prices is also addressed. The results show strong evidence of substitution between labor and the three categories of machinery inputs. The findings also support substitution among the three categories of machinery themselves.     

承接产业转移与中部地区高资本技术农业发展

高资本技术农业创新依赖于结构转换的深化。中部地区承接产业转移有助于深化结构转换,并对高资本技术农业创新产生拉动效应。坚持以城镇为载体承接非农产业转移和进一步完善农产品及农业要素市场,应该成为中部地区承接产业转移的重要政策选项。     

Effective Costs and Chemical Use in United States Agricultural Production: Using the Environment as a "Free" Input

A cost–function–based production model is used to represent patterns of input use and output production in U.S. agriculture, and the implied costs of induced reductions in risk from agricultural chemicals ("bad outputs"). We estimate and evaluate shadow values for these harmful outputs, and the implied input– and output–specific substitution patterns, with a focus on the impacts on pesticide demand and its quality and quantity components. Using state–level data we find these measures to be statistically significant, vary substantively by region, and imply increased demand for effective pesticides associated with improvements in quality from embodied technology.