隋唐五代时期园艺作物的培育与引进

隋唐五代时期是我国园艺业发展史上的重要时期。多种园艺作物培育成功并有为数不少的域外作物引进中土。这些新品种的花果、蔬菜、香料等，为我国园艺业增添了新的内容，丰富了人民生活。有的作物后来传到国外，为世界园艺提供了宝贵的种质资源。培育与引进的成功，则是与隋唐五代时期经济发展、气候条件适宜以及园艺技术提高等因素紧密相关的。     

陕西特色农产品的品牌经营战略研究

陕西具有发展特色农业的良好条件，但由于受自然经济传统约束，广大农民缺乏市场经营意识和经营经验，加之缺乏有效的农业合作组织，缺少辐射带动能力强的龙头企业，导致特色农产品的品牌化经营程度低，现有特色农产品的品牌知名度和美誉度不高，市场影响力有限。要创建陕西特色农产品品牌，必须提高特色农产品的生产者、经营者和地方政府的市场意识、品牌意识，组织专业协会，发展龙头企业，完善特色农产品技术服务支持体系，推行标准化生产，加强产后商品化处理，建立和完善农产品品牌质量认证体系，加强对农产品品牌的宣传推广力度。     

Economic Potential of Biomass Based Fuels for Greenhouse Gas Emission Mitigation

Use of biofuels diminishes fossil fuelcombustion thereby also reducing net greenhousegas emissions. However, subsidies are neededto make agricultural biofuel productioneconomically feasible. To explore the economicpotential of biofuels in a greenhouse gasmitigation market, we incorporate data onproduction and biofuel processing for thedesignated energy crops switchgrass, hybridpoplar, and willow in an U.S. AgriculturalSector Model along with data on traditionalcrop-livestock production and processing, andafforestation of cropland. Net emissioncoefficients on all included agriculturalpractices are estimated through crop growthsimulation models or taken from the literature. Potential emission mitigation policies ormarkets are simulated via hypothetical carbonprices. At each carbon price level, theAgricultural Sector Model computes the newmarket equilibrium, revealing agriculturalcommodity prices, regionally specificproduction, input use, and welfare levels,environmental impacts, and adoption ofalternative management practices such asbiofuel production. Results indicate no rolefor biofuels below carbon prices of $40 perton of carbon equivalent. At these incentivelevels, emission reductions via reduced soiltillage and afforestation are more costefficient. For carbon prices above $70,biofuels dominate all other agriculturalmitigation strategies.     

Bioenergy Crop Production in the United States: Potential Quantities, Land Use Changes, and Economic Impacts on the Agricultural Sector

The U.S. Departments of Agriculture and Energyjointly analyzed the economic potential for,and impacts of, large-scale bioenergy cropproduction in the United States. Anagricultural sector model (POLYSYS) wasmodified to include three potential bioenergycrops (switchgrass, hybrid poplar, and willow). At farmgate prices of US $2.44/GJ, anestimated 17 million hectares of bioenergycrops, annually yielding 171 million dry Mg ofbiomass, could potentially be produced at aprofit greater than existing agricultural usesfor the land. The estimate assumes highproductivity management practices are permittedon Conservation Reserve Program lands. Traditional crops prices are estimated toincrease 9 to 14 percent above baseline pricesand farm income increases annually by US $6.0billion above baseline.At farmgate prices of US $1.83/GJ, anestimated 7.9 million hectares of bioenergycrops, annually yielding 55 million dry Mg ofbiomass, could potentially be produced at aprofit greater than existing agricultural usesfor the land. The estimate assumes managementpractices intended to achieve highenvironmental benefits on Conservation ReserveProgram lands. Traditional crops prices areestimated to increase 4 to 9 percent abovebaseline prices and farm income increasesannually by US $2.8 billion above baseline.     

Refining the debate on GM crops using technological foresight—the Danish experience

Rapid developments in and the controversial nature of biotechnology call for communication, networks, partnerships, and collaboration in research, not just among researchers, but also between researchers and research “users” in industry, government, and elsewhere. Technological foresight appears to offer a coordinating method for developing and strengthening those linkages. To test this, a technological foresight study was performed on genetically modified (GM) crop technology in the Danish context. The background of the study was the conflict and intense debate in Denmark over applications of gene technology, especially over the deliberate release of genetically modified (GM) crops. However, the current debate characteristically involves sharply opposed fronts, lacking willingness and courage to engage in a free-flowing and open-minded debate on both rational and normative components of biosafety. In it, stakeholders and experts on both side of the conflict advocate widely differing opinions. Without a proper generally intelligible dialogue, the broader public audience finds it hard to comprehend this type of debate. The study pursues the notion that public dialogue can act as a driver of future applications in the technological domain, specifically GM crops. The study concluded with a stakeholder workshop that revealed three key issues that might provide helpful starting points for a more free-flowing and open-minded debate about the future of GM crops. The issues were those arising from the following statements: a broad perspective on risk is crucial; international regulation must make allowance for developing countries; a better configuration of the risk debate is needed. These issues are discussed in more details in the article.     

我国农作物秸秆资源化利用的经济分析:一个理论框架

农作物秸秆是生物质资源的主要来源之一,与之相关的技术开发目前已成为生态农业和可持续发展的一个重大课题。农作物秸秆资源化利用有肥料、燃料、饲料、工业原料和食用菌基料等多种途径和技术路径,这些利用方式和技术的经济可行性如何,引起了研究者越来越多的关注。文章提供了一个对我国农作物秸秆资源化利用行为进行经济分析的理论框架。在该框架中,农作物秸秆资源化利用的总收益包括秸秆产品的市场价值、秸秆资源使用节约的相关资源性产品价值以及秸秆产品使用产生的环境收益;农作物秸秆资源化利用的总成本则由秸秆的收集、运输、储藏、加工以及机会成本构成。最后,文章对农作物秸秆资源化利用的公共政策等问题进行讨论。     

2000～2010年我国洪涝灾害损失综合评估及其成因分析

利用我国的洪涝灾害损失数据,分析了我国2000～2010年洪涝灾害受灾人口、农业受灾面积和直接受灾经济损失之间的关系,洪涝灾害损失的空间分布特征以及受灾损失与年平均降水量之间的关系。根据近10年来我国洪涝灾害的新特点,提出了我国洪水管理及防灾减灾的若干措施。     

Cropland use,yields, and droughts: spatial data modeling for Burkina Faso and Niger

For countries with recurrent droughts, the design of drought impact mitigation measures could benefit from analyses of determinants of yields and prices of local crops at regional and district level. This study applies dynamic spatial panel data regression models to yields and prices of four major food crops across regions of Burkina Faso and Niger, over sample periods between 1984 and 2006. Results lend support to mainly simultaneous spatial spillovers, particularly for millet and cowpea prices and sorghum yields in Niger, and maize yields in Burkina Faso. After accounting for these effects, most crop yields are found to be weakly price‐responsive, as envisaged by a supply‐side geographical diffusion hypothesis. Seasonal rainfall elasticity estimates suggest that dominant food crops have slight advantage margins in terms of relative resilience to rainfall shortages. However, this result is to be weighed against low millet yields in Niger, and marked drops in sorghum yields during officially declared droughts in Burkina Faso.