Biofuel policies and the environment: Do climate benefits warrant increased production from biofuel feedstocks?

We examine whether climate benefits warrant policies promoting biofuel production from agricultural crops when other environmental impacts are accounted for. We develop a general economic-ecological modelling framework for integrated analysis of biofuel policies. An economic model of farmers' decision making is combined with a biophysical model predicting the effects of farming practices on crop yields and relevant environmental impacts. They include GHG emissions over the life cycle, nitrogen and phosphorus runoff, and the quality of wildlife habitats. We apply our model to crop production in Finland. We find that under current biofuel production technology the case for promotion of biofuels is not as evident as has been generally thought. Only reed canary grass for biodiesel is unambiguously desirable, whereas biodiesel from rape seed and ethanol production from wheat and barley cause in most cases negative net impacts on the environment. Suggested policies in the US and the EU tend to improve slightly the environmental performance of biofuel production.     

Land use change, biomass production and HANPP: The case of Hungary 1961-2005

This paper presents an empirical analysis of the human appropriation of aboveground net primary production (aHANPP) in Hungary in the years 1961-2005. In this period aboveground HANPP dropped from 67% to 49% of the potential vegetation's NPP. The trajectory was not smooth, but aboveground HANPP fluctuated with changes in factors affecting agricultural production conditions. Both aboveground net primary production (aNPP) of the prevailing vegetation and harvested aNPP increased during the socialist regime, dropped when the system collapsed and has shown considerable fluctuations since. We discuss the development of aboveground HANPP and the Hungarian land use system in the context of socioeconomic changes during three distinct phases: (1) industrialisation of agriculture (1961-1989), (2) regime collapse (1989-1993) and (3) restructuring of a new economy (1993-2005). Within these periods, different driving factors influenced aboveground HANPP and its constituents. In the phase of industrialisation, mechanisation and agrochemical inputs reduced aHANPP while harvested amounts of biomass increased progressively. In the second phase, political and economic circumstances devastated production conditions resulting in a decline of productivity of actual vegetation and a temporary rise in aboveground HANPP. During the last twelve years, industrialisation patterns of agricultural production recovered. The restructuring of inefficient agricultural production systems raised harvest at moderate levels of agricultural inputs, while climatic conditions intimidated high yield and harvest security. The paper discusses the effect of different economic and political regimes and of major socioeconomic restructuring on the development of the land use system, biomass production and aboveground HANPP.     

Input-Orientated Data Envelopment Analysis Framework for Measuring and Decomposing Economic,Environmental and Ecological Efficiency: An Application to OECD Agriculture

This paper presents an input-orientated data envelopment analysis (DEA) framework which allows the measurement and decomposition of economic, environmental and ecological efficiency levels in agricultural production across different countries. Economic, environmental and ecological optimisations search for optimal input combinations that minimise total costs, total amount of nutrients, and total amount of cumulative exergy contained in inputs respectively. The application of the framework to an agricultural dataset of 30 OECD countries revealed that (i) there was significant scope to make their agricultural production systems more environmentally and ecologically sustainable; (ii) the improvement in the environmental and ecological sustainability could be achieved by being more technically efficient and, even more significantly, by changing the input combinations; (iii) the rankings of sustainability varied significantly across OECD countries within frontier-based environmental and ecological efficiency measures and between frontier-based measures and indicators.     

Subsidies under uncertainty: Modeling of input- and output-oriented policies

Agricultural subsidies play an essential role in agricultural and rural development in many developed economies. Countries have implemented agricultural subsidy policies with a focus on food security and environmental protection. Agricultural production is risky and uncertain, influencing the efficiency of agricultural subsidies. This study develops a theoretical framework to analyze the effects of production uncertainties on the efficiency of agricultural subsidy policies under the double constraints of food security and environmental protection. The basic model is investigated under six different conditions, and expanded research also is presented. Our models show that uncertainty, including output, cost, and price uncertainties, and technology conversion efficiency significantly affects the efficiency of agricultural subsidies. Under high technology conversion efficiency, output-oriented subsidies are appropriate for food security and environmental protection goals. Policymakers should take both uncertainty and production efficiency into consideration when choosing between input-oriented and output-oriented subsidy policies.     

Mexican agricultural trade under the GATT

Expected effects from partially lifting tariff barriers on the Mexican agricultural sector are investigated using a restricted profit function (RPF) approach. Short-run and intermediate-run effects of the implementation of GATT minimum tariff provisions on Mexican agricultural trade are examined. Specification tests reveal the appropriateness of the RPF approach, that exports should not be aggregated with non-traded production into a single output, and that the farm sector behaves as an ‘almost’ price-taking, profit-maximizing firm. Policy simulations suggest important short-run changes in agricultural trade and chemical use and intermediate-run changes in agricultural trade, labour wage, chemical use, capital investments, and net farm income.     

碳排放约束下中国省际农业生产效率 及其影响因素研究

本文从系统论的角度出发,将农业碳排放量纳入农业生产效率研究框架内。首先,综合运用3个DEA模型,测算了2004-2010年中国30个省份农业生产效率,探索中国各省份、三大地区间的效率差异,并给出农业资源利用效率的4种模式,然后,利用Tobit模型检验农业生产效率的影响因素。结果表明：考察期内中国农业生产效率有所提升,但仍处于较低水平,纯技术效率低下是制约农业生产效率提升的主要因素;各省份、三大地区间效率差异明显,东部地区最高,而中西部地区均低于全国平均水平;全国有60%的省份农业资源利用模式为低经济低环境效率型,这些省份主要来自于中西部地区;农田抗灾能力、农村用电量和研发经费的提高对全国农业生产效率的提升具有积极影响,而基础教育水平、产业结构以及农村金融支持的影响并不显著。     

Measuring total productivity change

This paper examines several ways of measuring the aggregate rate of technical change: with the aggregate production function; in a disaggregated framework of the multisector model; and with the net social production possibility frontier or the generalized factor price frontier. Conditions under which all three approaches are mutually compatible are determined.     

可持续性与数字化:区块链驱动的循环农业研究

区块链技术作为一种颠覆性的数字技术,具有去中心化、开放性、共享性、匿名性、可溯源性等特征,它可以完善农产品的食品安全认证、优化农产品的物流体系结构、革新农业组织的分工合作模式,但目前关于区块链应用于循环农业的研究尚不多见。论文研究搜索并梳理了相关文献知识,根据循环农业以及区块链的技术特征,以北京留民营生态农场为案例,提出了一个基于区块链的数字化循环农业框架,详细阐述了分布式账本、共识算法、代币机制、智能合约等区块链核心技术在框架中的应用。该框架将区块链的“数字化”赋能与循环农业的“可持续性”内涵相融合,能够解决留民营有机蔬菜以次充好、农药残留、生产流程不规范等问题。最后探讨了研究的不足之处并提出未来研究方向,为进一步深入探析区块链在循环农业中的应用研究提供了参考。     

A dynamic multi-commodity model of the agricultural sector: A regional application in Brazil

This paper develops a dynamic model to analyze the development process in the agricultural sector. Formulated as a recursive linear programming model, it contains several commodities as outputs, farm and regional resource constraints on owned and purchased inputs-including working capital-and several farm sizes. The objective function is assumed to be separable for each farm size and additive for the region and measures for each year the net expected revenues from crop and livestock production less an investment charge. Prices are exogenous. The model is applied to a rapidly developing agricultural region in Southern Brazil and tested for its ability to trace regional farm sector development over a decade. It is then used to analyze the impact of alternative agricultural policies including price and credit subsidies.     

农业公共投资、竞争力与粮食安全

入世后中国的粮食生产将面临巨大的挑战。与世界主要粮食出口大国相比 ,我国的粮食生产成本上升、竞争力下降 ,其重要原因之一是我国的农业生产基础设施薄弱 ,尤其是政府对农业科研的投入不足。本文用实证分析的方法研究增加农业科研投入对增强我国主要粮食产品竞争力的影响 ,认为以提高科研投入等农业生产公共投资增强我国粮食的生产和竞争能力是应对入世挑战和实现未来粮食安全可持续发展的一个有效选择。     

Population growth,soil fertility,and agricultural intensification

This paper presents a renewable resource model of soil fertility with a nonconvexity in the net benefit function. In this setting, recurring cycles of cropping and fallow can be the optimal soil management strategy. The model is used to illuminate the Boserup discussion of agricultural development, in which population growth leads to agricultural intensification, defined as an increase in cropping frequency. Previous formal models of the Boserup hypothesis focus on the land-labor ratio rather than cropping frequency and have not directly incorporated soil fertility dynamics. These models assume a convex production technology and are not optimistic about the prospect for agricultural development without technological progress. This paper explicitly models soil fertility dynamics and demonstrates that nonconvexities in the production technology are an important feature of the use of long fallow periods for soil management. As population grows, and the demand for food increases, the importance of the nonconvexity diminishes and more frequent cropping becomes economical. Given a nonconvexity in the production technology, it is possible, though not necessary, that average labor productivity increases with agricultural intensification. Thus, it is possible to reconcile the greater labor requirement of intensive farming with an increase in average labor productivity. In addition, Boserup argued that a larger and denser population facilitates the development of economic and social infrastructure which improve agricultural productivity.     

The impact on Greek agriculture from membership in the European economic community

This paper estimates empirically the impact of Greek membership in the European Economic Community (EEC) on production, consumption, and trade of 18 major agricultural products of Greece. The model used combines the limited available data into a multiproduct supply and demand framework and quantifies the effect of transferring the EEC agricultural price structure on Greece. The basic results indicate that Greek farmers would lose substantially and their agricultural balance of trade seriously deteriorate, while Greek consumers would not be seriously affected as a consequence of EEC membership in 1986. Sensitivity analysis on several key assumptions and consideration of structural effects seem to support these conclusions.     

Measures of the effects of agricultural practices on ecosystem services

Agriculture produces more than just crops. Agricultural practices have environmental impacts that affect a wide range of ecosystem services, including water quality, pollination, nutrient cycling, soil retention, carbon sequestration, and biodiversity conservation. In turn, ecosystem services affect agricultural productivity. Understanding the contribution of various agricultural practices to the range of ecosystem services would help inform choices about the most beneficial agricultural practices. To accomplish this, however, we must overcome a big challenge in measuring the impact of alternative agricultural practices on ecosystem services and of ecosystem services on agricultural production. A framework is presented in which such indicators can be interpreted as well as the criteria for selection of indicators. The relationship between agricultural practices and land-use change and erosion impact on chemical use is also discussed. Together these ideas form the basis for identifying useful indicators for quantifying the costs and benefits of agricultural systems for the range of ecosystem services interrelated to agriculture.     

Trade,poverty, and social protection in developing countries

How do shifts in trade affect social protections for the poor? Although the fraction of the world's population considered the “extreme” poor has fallen by over one-half over the past quarter century, many of those lifted above the global poverty line remain vulnerable to shocks that could place them back into poverty. These are the groups that require social protection to stabilize their incomes. Among the shocks to which the absolute poor have been exposed are those created by trade liberalization, particularly of the agricultural sector. The resulting risks, uncertainties, and threats to social stability from this type of trade require that the poor be provided with some forms of adjustment assistance. We examine the effects of trade components on several dimensions of social protection in developing countries, including spending, coverage, and adequacy over the past two decades. We find that, contrary to previous studies, disaggregating trade may be a key to determining which international market variables drive expansion of social protection. Disaggregating trade balances in agricultural vs. manufactured goods reveals that net food and agricultural exporters provide better social protection than countries that report agricultural trade deficits. Meanwhile, countries with manufacturing trade surpluses tend to experience reduced social protection coverage. We reason that governments of net agricultural exporters face incentives to invest in social programs that extend eligibility to the rural poor. Manufacturing export-driven economies, on the other hand, are likely participants in global production chains that limit the capacity of the public sector to extend social protection.     

Climate change driven shifts in the extent and location of areas suitable for export banana production

Species distribution modeling (SDM) is used to map areas predicted to be suitable for commercial banana production in Central and northwestern South America. Using the downscaled climate projections for 2060 from seven leading global climate models we then predict the geographical shifts in areas suitable for banana production. We repeat this process for conventional and organic banana production. Approximately half of the existing conventional plantations included in the analysis are located in areas predicted to become unsuitable for banana production by 2060. The overall extent of areas suitable for conventional banana cultivation is predicted to decrease by 19%, but all countries are predicted to maintain some suitable areas. The extent of areas suitable for organic banana cultivation is predicted to nearly double due primarily to climatic drying. Several countries (e.g., Colombia and Honduras) are predicted to experience large net decreases in the extent of areas suitable for banana cultivation. Some countries (e.g., Mexico) are predicted to experience large net increases in the extent of suitable areas. The shifts in the location of areas that will be suitable for banana cultivation are predicted to occur mainly within areas outside of protected areas and that are already under agricultural production.     

农业产业化对农民收入和农户行为的影响--以山东省龙口市为例

农业产业化是当今中国农业发展的热点，但产业化经营究竟能在多大程度上促进“三农”问题的根本转变，目前仍很少有人进行定量研究。文章以农业产业化起步较早的山东省龙口市为案例，通过生产调查和统计资料分析，对该问题做了初步研究。结果表明：尽管龙口市的乡村工业发展迅速且占据了农村经济的绝大部分，但与农民人均纯收入增长关系最为紧密的仍然是农业产业，其次才是农村第二、第三产业，这一结果应归功于农业产业化的发展。农户在家庭劳动力分配时，年老人趋向于从事农业生产，年轻人趋向于从事非农生产，许多农户将自家的劳动力投入到非农产业，同时又雇佣外地劳力从事自家的农业生产。     

农产品流通渠道的维度:基于政治经济分析框架的研究

本文提出了我国农产品流通渠道研究的政治经济分析框架,展示了该框架对于农产品流通问题分析的独特视角。根据政治经济分析框架,农产品流通渠道可以分为经济与行为两个维度,而现有的研究则主要集中在经济维度上,这突显出加强对行为维度研究的必要性与紧迫性。本文对农产品流通渠道行为维度进行了理论上的界定与探讨,同时提出,需要引入营销渠道行为理论和关系营销理论作为主要理论工具对农产品流通渠道展开研究。     

Incidence theory and the shifting of protection across sectors: the South Asian experience

Using the theoretical framework of a simple general equilibrium model, this paper examines whether strategies aimed at protecting or promoting manufacturing industries indirectly taxed the agricultural and service sectors. A panel data set consisting of five South Asian countries over a 26 year time period is employed in the analysis. Three different estimation procedures are used to account for factors that are country specific and those that are common to all countries. The results indicate that the agricultural sector indirectly felt the brunt of the net protection provided to manufactures due to the ‘shifting of protection’ across sectors. The service sector, on the other hand, indirectly benefited from the general equilibrium spillover effects.     

Spatially optimal habitat management for enhancing natural control of an invasive agricultural pest: Soybean aphid

By their direct effects on private profitability, invasive agricultural pests create special incentives for management that set them apart from other categories of invasive species. One attractive nonchemical management approach for agricultural pests relies upon biological control by natural enemies. By improving the habitat of natural enemies of invasive agricultural pests, biological pest control can become privately attractive. This study develops a spatial optimization model to explore economically optimal spatial configuration of natural enemy habitat in agricultural landscapes. The model is applied to the management of soybean aphid (Aphis glycines), a recent invasive pest species of soybean production systems in the North Central region of the United States. Results indicate that non-crop habitat management can be a promising pest management option for organic cropping systems. Under current prices, however, habitat management tends to reduce net returns for conventional farms. Both area and configuration of non-crop habitats affect economic performance, with the greatest value coming from small, scattered areas of habitat.     

A vertical social accounting matrix of the U.S. economy

Abstract

This article presents an adaptation of the square social accounting matrix used in economic planning and programming to the rectangular or vertical transaction matrix used in post Keynesian monetary economics. The objective is to obtain a simple and intuitive framework to organize macroeconomic data in terms of the main institutional sectors of the economy, showing how production, distribution, demand, and financing are inter-related. The article presents the social accounting matrix of the U.S. economy as an example and use it to analyze the trends in net lending and household net income since 1960.