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1.
Recent trends in farm productivity and food prices raise concerns about whether the era of global agricultural abundance is over. Agricultural R&D is a crucial determinant of agricultural productivity and production, and therefore food prices and poverty. In this article, we present entirely new evidence on investments in public agricultural R&D worldwide as an indicator of the prospects for agricultural productivity growth over the coming decades. The agricultural R&D world is changing, and in ways that will definitely affect future global patterns of poverty, hunger, and other outcomes. The overall picture is one in which the middle‐income countries are growing in relative importance as producers of agricultural innovations through investments in R&D, and have consequently better prospects as producers of agricultural products.  相似文献   

2.
Using data for a long panel of 90 developed and developing countries, this article explores the effects of research and development (R&D) and fixed capital stock on agricultural land productivity over the period 1961–2012. Instruments are used for R&D to deal with feedback effects and measurement errors. The results show very high social returns to investment in R&D and to fixed capital stock, suggesting that increasing investment in these factors are promising ways of arresting the increasing food prices due to increasing demand for animal protein, population growth, desertification, salinization, soil erosion, climate change, and decreasing growth in land productivity.  相似文献   

3.
Reported rates of return to agricultural R&D are generally high, but they are likely to be biased, particularly because of attribution problems—mismatching research benefits with costs. The importance of attribution biases is illustrated here with new evidence for Brazil. During 1981–2003, varietal improvements in upland rice, edible beans, and soybeans yielded benefits of $14.8 billion in present value (1999 prices) terms. Attributing all of the benefits to Embrapa, a public research corporation accounting for more than half of Brazil's agricultural R&D spending, the benefit-cost ratio would be 78:1. Under alternative attribution rules, the ratio drops to 16:1.  相似文献   

4.
This article empirically examines the impact of R&D and climate change on the Western Australian Agricultural sector using standard time series econometrics. Based on historical data for the period of 1977–2005, the empirical results show that both R&D and climate change matter for long‐run productivity growth. The long‐run elasticity of total factor productivity (TFP) with respect to R&D expenditure is 0.497, while that of climate change is 0.506. There is a unidirectional causality running from R&D expenditure to TFP growth in both the short run and long run. Further, the variance decomposition and impulse response function confirm that a significant portion of output and productivity growth beyond the sample period is explained by R&D expenditure. These results justify the increase in R&D investment in the deteriorating climatic condition in the agricultural sector to improve the long‐run prospects of productivity growth.  相似文献   

5.
Payments for environmental services (PES) have gained wide popularity as approaches to promote environmentally friendly land use or agricultural production practices. Yet academics have also voiced concerns against seeing PES as a panacea. This article discusses whether PES is an appropriate and promising approach to promote so‐called “climate‐smart agriculture” (CSA) practices, which we define as agricultural production practices that contribute to CO2 emission reductions and/or removals and provide benefits to farmers via increased productivity and profits and reduced vulnerability to climate change. PES appears most promising for the promotion of CSA practices in small‐scale farming contexts with low incomes. Effective design, however, requires solid estimates of cost and benefit flows from CSA adoption over time, accounting for differences in socioeconomic and ecological conditions, and addressing the risk of leakage. Funding for such PES will likely have to come from public sources, and seems most promising where synergies with other objectives such as agricultural development, food security, and climate adaptation or other environmental services exist. The potential of alternative approaches for CSA support such as taxation with rebates for CSA practices, CSA‐related investment support such as microcredits, and hybrid approaches such as conditional microcredit should be further investigated.  相似文献   

6.
Indian agricultural input industries have gone through a major transformation in the last 40 years. State owned firms grew during the Green Revolution and then stagnated or declined. Indian corporations that were protected from foreign competition are now exporters of agricultural tractors and pesticides. Foreign multinational corporations are rapidly increasing their role in the seed, pesticide, and tractor industries. Entry by large Indian firms and multinationals has increased competition in the input industries. Private agribusiness R&D in India grew from $23 million in 1985 to $250 million in 2009 in 2005 US dollars. This is the same time period as a transformation in the agricultural input industry, rapid growth in demand for agricultural inputs, breakthroughs in information technology and biotechnology, and changes in intellectual property rights. An econometric model was used to test whether the transformation of agricultural input industry was a major factor in the growth of R&D expenditure or not. This article analyzes a unique, firm level sales and R&D data set from the seed, pesticide, tractor, and fertilizer industries in 2000–2009. The estimated model indicates that agribusiness firms' R&D expenditures from 2000 to 2009 were positively related to variables associated with industry transformation such as firm size, ownership by multinationals, and declining industry concentration. The model also indicates that strengthening patent policy as well as growth in the size of research‐intensive industries like the seed industry contributed to the growth of agribusiness R&D in India.  相似文献   

7.
Spillovers     
Interstate and international spillovers from public agricultural research and development (R&D) investments account for a significant share of agricultural productivity growth. Hence, spillovers of agricultural R&D results across geopolitical boundaries have implications for measures of research impacts on productivity, and the implied rates of return to research, as well as for state, national and international agricultural research policy. In studies of aggregate state or national agricultural productivity, interstate or international R&D spillovers might account for half or more of the total measured productivity growth. Similarly, results from studies of particular crop technologies indicate that international technology spillovers, and multinational impacts of technologies from international centres, were important elements in the total picture of agricultural development in the 20th Century. Within countries, funding institutions have been developed to address spatial spillovers of agricultural technologies. The fact that corresponding institutions have not been developed for international spillovers has contributed to a global underinvestment in certain types of agricultural research.  相似文献   

8.
This article investigates the effects of sea level rise and climate change induced crop yield alterations on Taiwan as well as possible adaptation strategies. For sea level rise of up to 5 meters, as much as 4.9% of total acreage and 16% of rice acreage would be lost. The empirical findings show that the sea level damages range from NT$ 0.84 to 4.10 billion while crop yield losses range from NT$ 1.79 to 2.55 billion. We investigate alternative adaptation strategies finding crop yield technological progress and tariff reduction could significantly mitigate these effects.  相似文献   

9.
Agriculture research knowledge and technology that transcends national borders has played a crucial role in enhancing developing country productivity growth over the past 50 years. The demand for international agriculture research (IAR) continues to be strong today even while becoming increasingly differentiated by the stage of development that a particular country or region is in. The supply of IAR to developing country research programs is, however, becoming increasingly constrained by: variable donor support; a push toward downstream product adaptation and dissemination activities relative to innovation and product development; and a lack of clear links between international public good research and national agriculture development priorities. Country‐level donor coordination and alignment mechanisms, specified in the Paris Declaration on Aid Effectiveness, do not explicitly account for the role of IAR in the development process. While the movement toward national ownership of its development agenda and donor alignment around it is unquestionably good, an unintended consequence could be a break in the R&D pipeline that supplies public good research and technologies for enhancing developing country agriculture productivity growth. The article presents options for rebuilding synergies between international public good research and national agriculture development priorities.  相似文献   

10.
Relative agricultural productivity shocks emerging from climate change will alter regional cropland use. Land allocations are sensitive to crop profits that in turn depend on yield effects induced by changes in climate and technology. We develop and apply an integrated framework to assess the impact of climate change on agricultural productivity and land use for the U.S. Northern Great Plains. Crop-specific yield–weather models reveal crop comparative advantage due to differential yield impacts of weather across the region's major crops, that is, alfalfa, wheat, soybeans, and maize. We define crop profits as a function of the weather-driven yields, which are then used to model land use allocation decisions. This ultimately allows us to simulate the impact of climate change under the RCP4.5 emissions scenario on land allocated to the region's major crops as well as to grass/pasture. Upon removing the trends effects in yields, climate change is projected to lower yields by 33–64% over 2031–2055 relative to 1981–2005, with soybean being the least and alfalfa the most affected crops. Yield projections applied to the land use model at present-day input costs and output prices reveals that Dakotas’ grass acreage will increase by up to 23%, displacing croplands. Wheat acreage is expected to increase by up to 54% in select southeastern counties of North Dakota and South Dakota, where maize/soy acreage had increased by up to 58% during 1995–2016.  相似文献   

11.
This paper describes the identification, specification, estimation, and evaluation of econometric models of knowledge productivity and the returns‐to‐research. General issues related to these models are discussed and placed in context of the literature. The path from R&D investment to economic benefit is complex, convoluted, generally unknown and possibly misrepresented. The complexity arises from the intricate spatial spillover relationships and the very long time periods involved, which complicate any econometric analysis. The relevant R&D investment data are typically unavailable, incomplete and poorly measured (or approximated). The appropriate calculation of the financial benefit is not entirely clear. Some parsimonious suggestions for future research are presented.  相似文献   

12.
We use newly constructed data to model and measure agricultural productivity growth and the returns to public agricultural research conducted in Uruguay over the period 1961–2010. We pay attention specifically to the role of levy‐based funding under INIA, which was established in 1990. Our results indicate that the creation of INIA was associated with a revitalization of funding for agricultural R&D in Uruguay, which spurred sustained growth in agricultural productivity during the past two decades when productivity growth was stagnating in many other countries. The econometric results were somewhat sensitive to specification choices. The preferred model includes two other variables with common trends, a time‐trend variable and a proxy for private research impacts, as well as a variable representing the stock of public agricultural knowledge that entailed a lag distribution with a peak impact at year 24 of the 25‐year lag. It implies a marginal benefit‐cost ratio of 48.2, using a real discount rate of 5 per cent per annum and a modified internal rate of return of 24 per cent per annum. The benefit‐cost ratio varied significantly across models with different lag structures or that omitted the trend or the private research variable, but across the same models, the modified internal rate of return was very stable, ranging from 23 per cent per annum to 27 per cent per annum. These results suggest that the revitalized investment in research spending under INIA has been very profitable for Uruguay and that a greater rate of investment would have been justified.  相似文献   

13.
This article estimates agricultural productivity growth in 10 South American countries in 1969–2009 with the objective of investigating if the slowdown being measured in other countries is present in the region. Results show that productivity growth accounts for half of the three‐fold increase in agricultural output during this period and that performance is sensitive to R&D investments in the sector. The slowdown found for the 1990s to 2000s in the U.S. and some European economies does not seem to be present yet in South America. The region's total factor productivity (TFP) growth rate increased steadily from 1.07% during the 1970s to 2.29% during the 2000s. Given lags in adoption and the adaptive nature of innovations in these economies, we have yet to see the potential effects in South American agriculture of decreases in R&D in advanced economies.  相似文献   

14.
This study estimates the distributional heterogeneity in the effects of climate change on yields of three major cereal crops: rice, maize, and wheat in India using district-level information for the period 1966–2015. We distinguish between the effects of changes in growing season weather from those due to changes in long-term climate trends and the heterogeneity in these effects across the distribution of crop yields by estimating naïve and climate penalty inclusive models using fixed-effect quantile panel models. We observe an absence of adaptation against rising temperatures for rice and wheat. However, we find a statistically significant presence of adaptation for wheat and maize for changes in precipitation, though the magnitude is small. Moreover, we find that the effects are asymmetric, and are larger at the lower tail of productivity distribution and smaller at the upper tail of the distribution. A 1°C increase in temperature lowers rice and wheat productivity by 23% and 9%, respectively at the first quantile, but the damage is only 6% and 5% at the ninth quantile. Heterogeneity in impacts and adaptation estimates over the yield distribution curve and across crops suggests the importance of customizing strategies for adaptation to changing weather and climate conditions across regions, crops, and current productivity levels.  相似文献   

15.
Likely climate change impacts include damages to agricultural production resulting from increased exposure to extreme heat. Considerable uncertainty remains regarding impacts on crop insurance programs. We utilize a panel of U.S. corn yield data to predict the effect of warming temperatures on the mean and variance of yields, as well as crop insurance premium rates and producer subsidies. While we focus on corn, we demonstrate that the subsidy impacts are likely to carry over to other major program crops. We find that warming decreases mean yields and increases yield risk on average, which results in higher premium rates. Under a 1°C warming scenario, we find that premium rates at the 90% coverage level will increase by 39% on average; however, there is considerable statistical uncertainty around this average as the 95% confidence interval spans from 22% to 61%. We also find evidence of extensive cross‐sectional differences as the county‐level rate impacts range from a 10% reduction to a 63% increase. Results indicate that exposure to extreme heat and changes in the coefficient of variation are large drivers of the impacts. Under the 1°C warming scenario, we find that annual subsidy payments for the crop insurance program could increase by as much as $1.5 billion, representing a 22% increase relative to current levels. This estimate increases to 3.7 billion (57%) under a 2°C warming scenario. Our results correspond to a very specific counterfactual: the marginal effect of warming temperatures under current technology, production, and crop insurance enrollments. These impacts are shown to be smaller than the forecasted impacts under a commonly used end‐of‐century general circulation model for even the most optimistic CO2 emissions projection.  相似文献   

16.
The payoffs and distribution of payoffs from research and development (R&D) along the food value chain depend on many interacting economic factors. To quantify these, we have developed a general equilibrium model of the Australian economy with detailed farming, processing and marketing information. We use the model to assess potential payoffs and distributions from various R&D scenarios that lead to demand expansion and productivity improvement. We find that productivity improvement caused by R&D is unambiguously beneficial to the whole economy while the benefits of export or domestic market demand expansion mainly accrue to the primary producers and processing industry, when the economy is at full employment. Also, productivity improvement from R&D on‐farm may benefit processors while improvements postfarm may benefit farmers.  相似文献   

17.
In this article, we examine the relationship between public investments in agricultural research and development and the productivity‐enhancing benefits they generate. Knowledge productivity functions are estimated for U.S. agriculture using data on multifactor productivity and public knowledge stocks. We examine the time‐series properties of the data and compare alternative econometric estimation procedures. The results are used to calculate economic performance measures such as internal rates of return and benefit‐cost ratios. The real rate of return to public investments in agricultural research and development in the United States is in the range of 8–10% per annum.  相似文献   

18.
全球变化背景下气候变暖对中国农业生产的影响   总被引:5,自引:0,他引:5  
全球变化背景下,气候变暖势必对我国农业生产要素、生产环境、农业生产活动及粮食安全产生重大影响。文章采用文献综述与比较研究的方法,系统分析气候变化对我国光资源、温度、水环境和土壤环境等农业生产要素的影响特征及变化趋势,探讨气候变化对我国作物种植区域和种植制度、农作物病虫害、农业生产能力、农业经济与管理等农业生产活动以及农田生态系统过程、农业生态环境(水环境、土壤环境、耕作环境)的实际影响。在此基础上,明确了我国农业在应对气候变化过程中所面临的主要问题:极端气候事件发生频率加大,自然灾害、气象灾害的风险提高,农业生产的波动性增强;农业病虫害的为害时间延长、危害程度加剧、为害范围增大;农业生态环境日趋恶化,农田土壤的干旱化、盐渍化程度加剧,农业生产能力下降;应对气候变化的农业发展策略及其关键技术亟需解决。  相似文献   

19.
气候变化对粮食产量影响的研究方法综述   总被引:1,自引:0,他引:1  
[目的]受气候变化的影响,全球粮食安全面临严峻挑战,及时准确地评估气候变化对粮食产量的影响是应对挑战、制定农业适应性对策的关键。相关研究已产生了不少方法,通过综述对方法进行分类,明晰各种方法的优缺点和适用性,以期扬长避短,促进研究方法的综合、发展与完善。[方法]利用文献法、归纳法和比较法,从方法的原理和应用、存在的问题、发展的趋势3个方面进行探讨。[结果]产量分解法可用于分析粮食产量及其构成要素与不同生育期气候变化的关系,实验比较法一般用于粮食产量对单个气候因子或若干气候因子变化的敏感性分析,生产函数法适用于在农业生产系统中分析气候变化对粮食产量影响的边际效应,气候生产潜力模型法侧重于农业生产环境发展评估,作物生长模型法便于结合气候情景预测未来气候变化对粮食产量的影响。在不同研究方向上得以运用的同时,各方法也暴露了一些问题:产量分解法的技术产量难以拟合,实验比较法的数据获取难、模型稳定性较差,生产函数法容易遗漏重要变量、函数构造困难,气候生产潜力模型法的结论难以验证,作物生长模型法参数标定难、模型应用存在尺度错位。[结论]研究方法将逐渐形成一套综合的气候—水文—作物—经济模型法,多源数据融合和多目标模式已经成为方法发展的驱动力。  相似文献   

20.
Genetic resources for food and agriculture are the biological basis of world food and nutrition security; and they directly or indirectly support the livelihoods of over 2.5 billion people. Genetic diversity gives a species or a population the ability to adapt to changing environments. For resource-poor farmers, adaptive animal breeds, crop varieties and cultivars adapted to particular micro-niches, stresses or uses are the main resources available to maintain or increase production and provide a secure livelihood. The economic value of genetic diversity for productivity and yield traits is discussed in the literature. However, it is difficult to value many other aspects of agricultural biodiversity as these have both direct and indirect values in terms of qualitative traits such as food, nutrition and environmental uses that include adaptation to low input conditions, co-adaptive complexes, yield stability and the consequent reduction of risk, specific niche adaptation, and in meeting socio-cultural needs. Together, the direct and indirect values of genetic resources for resource-poor farmers are expressed in a range of options in the form of the crop varieties and species they use for managing changing environments.

The value of genetic diversity to resource-poor farmers is seldom captured by markets or addressed by the international research agenda. This paper presents lessons learned from our work over 5–10 years in the Asia and Pacific Ocean (APO) region on participatory crop improvement, home gardens and on-farm management of agricultural biodiversity. The lessons illustrate how farmers adapt genetic resources to suit local environmental conditions. The paper focuses on the value of genetic diversity of selected crop species to meet people's food and other needs. Genetic diversity valued by resource-poor farmers is often maintained, selected and exchanged by local social seed networks. Identification of such genetic resources and their custodians is important if international agricultural research is to contribute to the reduction of poverty. The paper highlights some good practices from case studies that illustrate how such genetic resources could be exploited by informal research and development strategies or participatory plant breeding or for marketing value-added products.  相似文献   

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