Conservation practice complementarity and timing of on-farm adoption

The adoption of conservation practices is a dynamic process. Factors that vary over time can affect farmers’ decision to adopt and adoption timing. We used a duration model to evaluate the farmer's adoption time for continuous no-till (CNT), cover crops (CCs), and the variable-rate application of inputs (VRA). We found that producers who had previously adopted soil conservation practices were more likely to adopt additional complementary practices. Farmers using crop rotation adopted CNT and CCs approximately 48% and 62% faster than farmers without a crop rotation, respectively. The CC adoption time was also reduced by 70% for farmers who had adopted CNT. Complementarities between conservation practices may enhance the benefits from adoption and allow farmers to adopt bundles of conservation practices more quickly over time. This can be taken advantage of in conservation programs by promoting or requiring practices first that enhance adoption of other practices. We also found important heterogeneity in the adoption speed associated with farm management characteristics, producers’ attitudes, weather patterns, and crop prices.     

Adopting bioenergy crops: Does farmers’ attitude toward loss matter?

We apply prospect theory to examining farmers’ economic incentives to divert a share of their land to bioenergy crops (miscanthus and switchgrass in this study). Numerical simulation is conducted for 1,919 rain‐fed U.S. counties to identify the impact of loss aversion on bioenergy crop adoption, and how this impact is influenced by biomass price, discount rate, credit constraint status, and policy instruments. Results show that ignoring farmer's loss aversion causes overestimation of miscanthus production but underestimation of switchgrass production, particularly when farmers are credit constrained and have a high discount rate. We find that establishment cost subsidy induces more miscanthus production whereas subsidized energy crop insurance induces more switchgrass production. The efficacy of these two policy instruments, measured by biomass production increased by per dollar of government outlay, depends on the magnitude of farmers’ loss aversion and discount rate.     

Agricultural commercialization and nutrition revisited: Empirical evidence from three African countries

The transition from subsistence to commercial agriculture is key for economic growth. But what are the consequences for nutritional outcomes? The evidence to date has been scant and inconclusive. This study contributes to the debate by revisiting two prevailing wisdoms: (a) market participation by African smallholders remains low; and (b) the impact of commercialization on nutritional outcomes is generally positive. Using nationally representative data from three African countries, the analysis reveals high levels of commercialization by even the poorest and smallest landholders, with rates of market participation as high as 90%. Female farmers participate less, but tend to sell larger shares of their production, conditional on participation. Second, we find little evidence of a positive relationship between commercialization and nutritional status. As countries and international agencies prioritize the importance of nutrition-sensitive agriculture, better understanding of the transmission channels between crop choices and nutritional outcomes should remain a research priority.     

山东省粮经作物播种比例演变及结构优化研究——基于1986～2015统计数据

[目的]目前我国农业主要矛盾是结构性失衡,作为种植业大省的山东省的农业结构性矛盾更为突出,种植业供给侧结构性改革势在必行。[方法]选取山东省1987~2016年农业统计年鉴中有关1986~2015年粮食作物和经济作物以及同类作物不同品种的播种面积的统计数据,运用统计分析法、图表法和对比分析法,分析山东省粮经作物播种面积比例演变特点,以及粮食作物和经济作物各自内部播种面积比例演变特点。[结果]30年间,山东省粮食作物播种面积及占比呈缓慢下降趋势,而经济作物播种面积和占比则持续上升,但大豆、棉花等经济作物国际市场依存度持续走高。从粮食作物和经济作物具体品种来看,玉米、蔬菜、瓜果播种面积持续大幅度上升,而大豆、棉花播种面积连年下降。[结论]山东省应在遵循国家发展粮经饲统筹的"三元"种植结构的政策导向基础上,兼顾种植户的经济利益,顺应消费者需求变化,从种植制度与生产方式安排、农作物品种选择、农作物品质提升3个方面进一步优化种植业结构。     

The seed and agricultural biotechnology industries in India: An analysis of industry structure,competition, and policy options

Since the late 1980s, technological advances and policy reforms have created new opportunities for private-sector investment in India’s seed and agricultural biotechnology industries. These changes have had a significant impact on cotton yields and output in India, but less so for rice and wheat—the country’s main cereal staples—for which yield growth rates are tending toward stagnation. This analysis examines the structures of these industries, their potential effects on competition and innovation, and the policies that may improve both industry performance and the delivery of new productivity-enhancing technologies to India’s cereal production systems. Our findings suggest that more substantive policy reforms are needed to encourage further innovation, reduce regulatory uncertainty, and encourage firm- and industry-level growth, while continued public spending on agricultural research is needed to support technological change.     

农作物新品种技术扩散机理与模式研究

农作物新品种的技术扩散不仅仅是新技术的推广过程,更关系到农业的可持续发展,关乎国计民生,因此必须重视农作物新品种在技术扩散过程中存在的问题并加以有效解决。通过研究农作物新品种技术的扩散机理与新品种扩散的几种常见模式,并针对现行的几种模式提出建议,为新品种的技术扩散提供借鉴。     

重庆市地表起伏度及其对农业生产的影响分析

重庆地貌复杂多样,地表起伏度大,通过对重庆各区县地表起伏度研究和计算,可定量了解重庆山水起伏骨架指数。以空间分辨率为30m、投影为WGS84_UTM的ASTER GDEM V2全球数字高程数据为基础,在ArcGIS10.1中利用投影面积比法计算重庆各区县地表起伏度指数,在此基础上分析了地表起伏度与2008~2013年各区县农业生产指标之间的相关性并建立系列模型。结果表明:1重庆西部较为平整,地表起伏度比中、东部地区低,地表起伏度最大的是东北部的城口、巫溪、巫山,最平整的是西部的荣昌、潼南、大足。2基于重庆市31个县域的统计分析,地表起伏度标准化指数每增加0.1,粮食单产减少约0.37t/hm~2,农林水支出占财政支出比例增加约1.1%。3地表起伏度对耕播面积比例影响力最大,其可决系数R~2达到0.8859。4农业产出不变时,农业投入随地表起伏度的增加而增加,地表起伏度与综合指标(农业产出投入比)所建指数模型的可决系数R~2为0.8296。     

全球转基因大豆发展概况

自1996年以来,全球转基因大豆得到迅速发展。从1996年至2004年,转基因大豆的种植面积从50万hm 2增至4840万hm 2,增长了约96倍;转基因大豆种植率从0.8%升至52.6%,增长了约63倍;转基因大豆分布国家从2个增至9个。在2004年,转基因大豆主产国依次是美国、阿根廷、巴西和巴拉圭。转基因大豆是全球最重要的转基因作物。虽然转基因大豆安全性存在很大争论,但是,全球转基因大豆预计仍将得到进一步发展,而中国仍将禁止商业化种植转基因大豆。     

On the asynchronous approvals of GM crops: Potential market impacts of a trade disruption of EU soy imports

Due to their high protein content, soybeans are important feedstuffs in the European Union (EU). However, the cultivation of soybeans using genetically modified (GM) varieties in non-EU countries is increasing and the EU authorization of GM products takes longer than in other countries, leading to an asynchronous approval between the EU and non-EU countries that might induce soybean trade disruptions. This paper uses an integrated modelling system to simulate Argentina, Brazil and the United States ending soybean exports to the EU. The impact on world trade and on the EU import prices of soy products is analysed with a computable general equilibrium model. EU soy imports are shown to decline, and the import price of soybeans in the EU increases. The effects on EU agricultural markets are analysed based on a partial equilibrium model. Feed costs in the EU are found to increase with poultry and pork the most affected: production and exports decline and imports increase. However, the effects of a trade ban are found to be less profound than in many other studies due to compensating substitution effects at various market levels: increasing imports from third countries, increasing domestic oilseed production and the use of other protein feeds.     

How would compliance with dietary recommendations affect revenues for agricultural producers?

Nutritionists and other health experts have recommended a range of dietary plans, and these often differ significantly. Although the USDA food guides have been the most visible in the United States, other dietary plans now are achieving greater public recognition. Our analysis extracts the nutrient recommendations for seven dietary plans and models the recommendations as shifts in demand for the nutrients. Demand shifts for nutrients are combined with nutrient composition shares to simulate the revenue implications in selected agricultural markets. Based on current consumption patterns in the United States, we find that compliance with Harvard’s Healthy Eating Pyramid would generate the greatest revenue gains for specialty crop producers in California.