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1.
As rice constitutes the major share in cereal consumption in South and East Asian countries that ranges from as low as 40 per cent in India to 97 per cent in Myanmar, to ensure food security, governments in these countries are encouraging farmers to adopt hybrid rice. This is mainly because hybrid rice provides a yield gain of 15–20 per cent over conventionally bred varieties in general. Yet, despite strenuous government efforts, farmers’ adoption rates have remained low in India, Bangladesh and Vietnam compared with China. Although studies often claim that higher seed costs and inferior grain quality are the major factors limiting hybrid rice adoption, very few studies examine the importance of socio‐economic factors and infrastructure in the adoption of hybrid rice. Using Bangladesh as a case, a comparative analysis has been made on the adoption of hybrid and modern varieties relative to traditional rice varieties and land allocation to these varieties. Econometric results indicate that general land characteristics, loan facilities and general infrastructure, such as roads, irrigation facilities and the availability of government‐approved seed dealers, significantly influence the adoption of hybrid and modern rice varieties and land allocation to these varieties compared with traditional varieties.  相似文献   

2.
Agricultural development is indispensable for poverty reduction and food security in sub‐Saharan Africa (SSA). This study investigates the impact of rice production training in a modified version of the System of Rice Intensification (SRI) on the performance of small‐scale rice farmers in a rainfed area of Tanzania. Utilizing the plot level variation, we employ propensity score matching (PSM) to assess the impact of training on technology adoption, productivity, and profitability. We also estimate a difference‐in‐differences model with plot fixed effects using recall panel data covering the periods before and after training. We found that trainees achieved an average paddy yield of 4.7 tons per hectare and rice profit of 191.5 USD per hectare on the plots where new technologies were adopted, which is higher by about 1.3–1.8 tons and 119–137 USD per hectare than on the other plots. Our study suggests the high potential of transforming favorable rainfed rice growing areas in SSA so as to achieve a rice Green Revolution through training in modern input use and improved agronomic practices.  相似文献   

3.
Strategies to reduce phosphorus and sediment yields are identified for two Australian catchments using a nonlinear optimisation model. This provides novel insight into the cost‐effective management of dual pollutants of water courses in Australia. A strong degree of complementarity between the two pollutants is highlighted, given the adsorption of phosphorus to sediment that augments the value of gully and streambank management for mitigation. However, the relationship between the two pollutants is asymmetric. A 30 per cent reduction in phosphorus yield achieves a 75 per cent reduction in sediment yield in one catchment, while a 30 per cent reduction in sediment yield achieves only a 12 per cent reduction in phosphorus yield. Sediment abatement costs are low given the efficiency of gully and streambank management. A 30 per cent phosphorus reduction lowers profit by 3–7 per cent, while a 30 per cent sediment reduction lowers profit by around 1 per cent. Land‐use optimisation requires spatial heterogeneity in land‐use and gully/streambank management responses. Overall, this research demonstrates the need to determine whether one pollutant is more important than another, while recognising the potential that mitigation practices possess for the reduction of multiple emissions during their evaluation.  相似文献   

4.
This study computes the eco‐efficiency of high‐yielding variety (HYV) rice production by including an on‐farm environmental damage index (OFEDI) as an undesirable output using data envelopment analysis. It then identifies its determinants by applying an interval regression procedure on a sample of 317 farmers from north‐western Bangladesh. Results reveal that the mean level of the OFEDI‐adjusted production efficiency (i.e. eco‐efficiency) is 89 per cent, whereas ignoring OFEDI adjustment (i.e. with OFEDI = 0) reduces the mean level of efficiency to 69 per cent, implying that the production of undesirable output or on‐farm environmental damage induces an efficiency loss of 20 per cent with significant differences across regions. The proportion of farmers’ income from HYV rice agriculture, land ownership, extension services and socio‐environmental living standard are the significant determinants of improving eco‐efficiency. Policy implications include investments in extension services and land reform measures to increase land ownership, which will synergistically improve eco‐efficiency of HYV rice production in Bangladesh.  相似文献   

5.
Applying programming techniques to detailed data for 406 rice farms in 21 villages, for 1997, produces inefficiency measures, which differ substantially from the results of simple yield and unit cost measures. For the Boro (dry) season, mean technical efficiency was 69.4 per cent, allocative efficiency was 81.3 per cent, cost efficiency was 56.2 per cent and scale efficiency 94.9 per cent. The Aman (wet) season results are similar, but a few points lower. Allocative inefficiency is due to overuse of labour, suggesting population pressure, and of fertiliser, where recommended rates may warrant revision. Second‐stage regressions show that large families are more inefficient, whereas farmers with better access to input markets, and those who do less off‐farm work, tend to be more efficient. The information on the sources of inter‐farm performance differentials could be used by the extension agents to help inefficient farmers. There is little excuse for such sub‐optimal use of survey data, which are often collected at substantial costs.  相似文献   

6.
Olive oil yields fluctuate strongly due to their dependence on sufficient precipitation. An interesting option to hedge the yield risk in olive cultivation could be satellite‐based weather index insurance. Therefore, we implement index insurance as a hedging alternative for non‐irrigated olive groves using MODerate‐resolution Imaging Spectroradiometer (MODIS) satellite data. For this purpose, we focus on the Spanish region of Andalusia, given its importance in olive production at the international level. We calculate three satellite indices: the Vegetation Condition Index (VCI), the Temperature Condition Index (TCI) and the Vegetation Health Index (VHI). Meteorological indices related to temperature and precipitation are used as benchmarks. Firstly, we estimate the periods that have the greatest influence on the critical vegetative phase of olives, which extends from March to September. Based on the indices, insurance contracts are designed using a copula approach, which is then employed to evaluate their hedging effectiveness. On average, the hedging effectiveness of VCI‐, VHI‐ and TCI‐based weather index insurance contracts amounts to 38 per cent, 38 per cent and 29 per cent, respectively. Moreover, VCI‐ and VHI‐based weather index insurance contracts outperform traditional weather index insurance contracts based on precipitation (by 29 per cent) and temperature (by 16 per cent) indices.  相似文献   

7.
This paper examines the newly constructed geographically scaled economic output measure, Gross Cell Product (GCP), of Australia and New Zealand to quantify the impacts of climate change in the region. The paper discusses advantages of using the GCP instead of the Gross Domestic Product. The paper reveals that the GCP falls sharply as temperature increases in the region. A 1°C increase in temperature would decrease the productivity with an elasticity of ?2.4. A 1 per cent decrease in precipitation would decrease productivity with an elasticity of ?2.3. However, forest vegetation on the coasts will benefit from initial warming. We find that the changes in climate means are potentially more harmful than changes in climate variability. In the long term, a 3.4° warming coupled with 6.6 mm decrease in rainfall would decrease the GCP by 34 per cent by 2060. The damage is largely accounted for by population effects. The paper confirms that Australia is highly constrained by climate and geographic factors.  相似文献   

8.
Based on farm census data, we explore the climate‐dependent incidence of six farm types and the climate‐induced impacts on land rental prices in Germany. We apply a structural Ricardian approach by modeling the dominant farm type at 9,684 communities as depending on temperature, precipitation and other geographic variables. Rents per farm type are then modeled as depending on climate and other conditioning variables. These results allow the projection of the consequences of climate change as changes in our climate variables. Our results indicate that permanent‐crop farms are more likely to dominate in higher temperatures, whereas forage or mixed farms dominate in areas of higher precipitation levels. Land rental prices display a concave response to increases in annual precipitation, and appear to increase linearly with rising annual temperature. Moderate‐warming simulation results for future decades benefit most farm types but seem to penalise forage farms. Rental prices are projected to increase, ceteris paribus, for all farm types.  相似文献   

9.
This paper addresses the prospects for technical change in the irrigated rice sector of Senegal, and measures ex‐ante the economic returns to recent research efforts. In 1994, three new rice varieties were released to farmers in the Senegal River Valley (SRV), the major irrigated rice region in Senegal. The productivity advantage of the new varieties is based primarily on early maturity, which permits double‐cropping. (The seeds are also higher yielding than existing cultivars.) We use a conventional [Akino and Hayami (1975), Am. J. Agric. Econ. 57, 1–10] partial‐equilibrium model adapted to the Senegalese situation, to assess the social benefits of research and compare those to its costs in calculating the internal rate of return (IRR). To account for uncertainty regarding the future values of model variables we use simulation which allows us to generate a distribution of all possible outcomes of the IRR. We find that rice research is almost certain to have a very high payoff over the 1995–2004 period. The expected value of the IRR is calculated to be 121% per year, with a 97.5% probability that it lies above annual capital costs of 18%. ©2001 Elsevier Science B.V. All rights reserved.  相似文献   

10.
目的 系统分析三江平原水稻产量的影响因素,对指导三江平原农业生产和耕地保护及减少未来粮食安全风险具有现实意义。方法 文章利用1988—2018年三江平原水稻产量、气象观测和社会经济数据,结合利用经济学模型——柯布-道格拉斯生产函数和统计学方法Lasso回归模型,分别分析社会经济因素和自然因素对三江平原水稻产量的影响。结果 (1)在社会经济因素方面,单位面积农村用电量和农业科研经费投入的单位面积增产效应比较明显,单位面积劳动力投入和化肥施用量对水稻产量具有负效应。(2)在自然因素方面,生长季内平均最低气温和平均日照时数对水稻产量有正向影响,生长季内总降水量和平均日相对湿度对水稻产量有负向影响。结论 为水稻生产提供政策建议: 可以通过合理施肥、加大机械化和农业科技创新的投入来提升水稻产量。同时,适当人工增加光照时间和加强冻害防治对提高水稻产量也具有重要意义。  相似文献   

11.
目的 运用生态效率的方法,评判粮食生产能否协调好口粮保供、粮农保收和生态保育之间的关系,对我国粮食生产可持续发展政策制订提供参考。方法 文章以生产力和赢利性双重目标为约束,以碳排放和农田污染为非期望产出,运用DEA-SBM模型,以粳稻主产省为测评对象,分析我国粮食连年丰产期粳稻生态效率及其时空演变特征,诊断生态效率的短板。结果 2004—2018年我国粳稻生态效率年平均值为0.858 4,无明显上升趋势,总体处于较高水平;东北稻区的黑龙江、吉林、辽宁,长江中下游稻区的江苏、安徽,以及西南稻区的云南,粳稻生产处于生态相对高效水平,华北稻区和西北稻区则处于生态相对低效水平;生态效率损失主要由农化物资及排灌费的高投入,以及非期望产出的高冗余造成。结论 我国粳稻实现高产的环境代价仍较大,全国粳稻生态效率地域差异明显,未来粳稻生产可适当向生态相对高效区域集中。  相似文献   

12.
Rice is Indonesia's staple food and accounts for large shares of both consumers' budgets and total employment. Until recently, Indonesia was the world's largest importer, but rice import policy is now highly protectionist. Since early 2004, rice imports have been officially banned. Advocates of this policy say it reduces poverty by assisting poor farmers. Opponents say it increases poverty, stressing negative effects on poor consumers. This paper uses a general equilibrium model of the Indonesian economy to analyse the effects of a ban on rice imports. The analysis recognises 1000 individual households, including all major socioeconomic categories, disaggregated by expenditures per person. It takes account of effects on each household's real expenditure and its income, operating through wages and returns to land and capital. The results indicate that the rice import ban raises the domestic price of rice relative to the import price by an amount equivalent to a 125 per cent tariff, six times the pre‐2004 tariff. Poverty incidence rises by a little under 1 per cent of the population and increases in both rural and urban areas. Among farmers, only the richest gain. These results are qualitatively robust to variations in key parametric assumptions.  相似文献   

13.
There is extensive scientific evidence on climate impacts and adaptation in rice (Oryza sativa L.), but the majority relates to production in South Asia and China. Only a handful of studies have been conducted in Sub-Saharan Africa and none in Malawi. In this paper, the climate impacts on rain-fed and irrigated rice yield have been assessed by combining the downscaled outputs from an ensemble of general circulation models (GCM) (HADCM3, INCM3 and IPCM4) with data from the LARS-WG weather generator to drive the CERES-Rice crop model. This was calibrated and validated using 10 years (2001–2010) field data from three rice schemes to simulate the baseline (1961–1990) yield (t?ha?1) and then model future yield changes for selected (B1 and A2) emissions’ scenarios for the 2050s. Although relatively small increases in average yield were projected (+8% and +5% for rain-fed and irrigated rice, respectively), there was large uncertainty (?10% to +20% yield change) when considering different GCMs and emission scenario. Farmer responses to cope with the projected impacts include both autonomous and planned adaptation strategies, such as modifying planting dates to maximize crop growth calendars and available soil moisture, increased use of on-farm water conservation measures and land levelling to improve water efficiency in rice schemes dependent on surface irrigation.  相似文献   

14.
As an economic and market‐transparent program, weather index insurance is expected to mitigate asymmetric problem. Capturing the relationship between yield and weather factor(s) is the basis of index insurance, but remains a challenge for weather index schemes. Meanwhile, composite weather index insurance is needed by farmers when their agricultural activities involve several risks, but is rarely studied. We aim to design a composite weather index insurance model and evaluate its efficiency in hedging yield risk by using the case of rice production in China. We divide the whole growth cycle of rice into six stages on the basis of agronomic knowledge, and use the average value of each weather factor in each stage to design a weather index. Then, the efficiency of composite weather index insurance is evaluated by mean‐semivariance and value‐at‐risk methods. First, we find that subdivision of the growth cycle helps to better capture the subtle relationship between rice yield and weather factors. Second, composite weather index insurance evidently reduces yield risk. Our findings help further adoption of weather index insurance in agricultural fields.  相似文献   

15.
The paper presents data and results from the World Energy Outlook (WEO) 2014, published by the International Energy Agency (IEA). Over the period to 2040, total energy use is projected to grow by almost 40 per cent, while the share of fossil fuels in the energy mix falls. Nonetheless, these fossil fuels remain the dominant sources of energy, with oil, coal and gas each accounting for around one quarter of global energy needs by 2040. Increasingly, modern renewables are projected to replace fossil fuels, especially in the power sector. Around 93 per cent of the projected increased primary energy demand comes from non‐OECD countries, with two‐thirds coming from developing Asia, led by China. By 2025, China could account for almost a quarter of global energy use, doubling its share since the turn of the century. After 2025, India and other Asian countries surpass China as the main centres of energy demand growth. The IEA's WEO 2014 concludes that even taking into account ambitious policy measures announced as of mid to late 2014, energy growth projections place the world on a path consistent with a long‐term temperature increase of 3.6 degrees. Urgent action is required if the world's energy systems are to be steered towards lower greenhouse gas emissions.  相似文献   

16.
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   

17.
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   

18.
The welfare cost of Japanese rice policy is estimated in the context of a large importing country, treating domestically produced rice and imported rice as heterogeneous goods and where there is home‐good preference. Not accounting for this preference will cause the gains from liberalisation to be overestimated. The period that is analysed is 2004–2007, departing from that in previous studies, which do not cover this period of greater deregulation. Rather than use border trade flow data as is customary, we acknowledge the actions of a state trading enterprise and construct and use a unique data set which should better gauge import penetration in the Japanese market for rice. Econometric estimation fails to reject the hypothesis that the Ministry of Agriculture, Forestry and Fisheries prevents imports from affecting the price of domestically produced rice. In the absence of precisely estimated parameter values, simulations of liberalisation are conducted under a range of parameter values and the effects on social welfare calculated. The tariff equivalents of the government's support to rice producers are also estimated with values for the period in excess of 100 per cent.  相似文献   

19.
Zvi Griliches’ seminal analysis of hybrid corn spawned a large literature seeking to quantify and demonstrate the value of agricultural research and development (R&D) investments. The most important metric for quantifying the rate of return to R&D emerging from this literature is the internal rate of return (IRR), even though Griliches was sceptical of its usefulness as a metric in this context. An alternative metric, also reported by Griliches but not as commonly used in the subsequent returns‐to‐research literature, is the benefit–cost ratio (BCR). We assess how the implications of the returns to agricultural R&D literature may have differed if the BCR had become the standard rather than the IRR. We reveal that the IRR and BCR produce substantially different rankings of agricultural R&D projects, differences that persist even under various commodity and geographical aggregations of the BCR and IRR estimates. The median across 2,627 reported IRRs is 37.5 per cent per year. Using data gleaned from 492 research evaluation studies, we developed and deployed a methodology to impute 2,126 BCRs (median of 5.4) and modified internal rates of returns (MIRRs, median of 16.4 per cent per year) assuming a uniform 10 per cent per year discount rate and a 30 year research timeline.  相似文献   

20.
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   

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