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1.
Are farmers better stewards of the land they own than the land they rent from others? We answer this question using a data set that identifies Ontario farmers’ conservation practices on their own land as well as the land they rent. Using a fixed‐effects regression approach, we find that the role of tenure varies for different types of conservation practices. Farmers were found to be just as likely to adopt a machinery‐related practice such as conservation tillage on their rented land as that land which they own. On the other hand, farmers were found to be less likely to adopt site‐specific conservation practices such as planting cover crops on rented land. However, this effect diminishes as the expected length of the rental relationship increases when the landlord has a farming background.  相似文献   
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[目的]文章评估了价格支持政策对不同粮食作物播种面积变化的平均效应与动态效应,并测度多种价格支持政策的交叉政策弹性。[方法]基于1998—2016年实施粮食价格支持政策省份面板数据,设立对照组,利用倾向得分匹配—双重差分方法(PSM DID)评估价格支持政策平均效应与动态效应,并构建粮食作物供给反应(Nerlove)模型测度价格支持政策的交叉政策弹性。[结果](1)价格支持政策对水稻、小麦、玉米播种面积增加具有不同程度的推动作用,按大小依次为玉米>水稻>小麦,对大豆播种面积变化影响不显著; (2)价格支持政策持续时间越长,对水稻、玉米播种面积增加的推动作用越大,对小麦播种面积增加的推动作用较为稳定; (3)小麦、玉米播种面积变化主要来自自身价格支持政策,水稻播种面积变化除了受到自身价格支持政策影响外,还受到其他作物政策影响,大豆播种面积变化对玉米临储政策反应敏感,对自身价格支持政策反应不敏感。[结论]在制定粮食政策时既要区分政策及其持续性对不同粮食播种面积变化的影响差异,又要注意在同一地区实施多种粮食政策时,可能对不同作物产生交叉影响。  相似文献   
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Crop insurance may affect harvested acreage and yield by influencing producers’ behavior such as land allocation and input use. Although specialty crops are a major source of farm income, especially on the U.S. west coast, they have not received as much attention as field crops in previous empirical studies. This paper assesses the effect of moral hazard and adverse selection associated with the federal crop insurance program (FCIP) on the acreage and yield of major specialty crops in California. An econometric method that expands the switching regression model is developed to assess the effect. Results suggest that federal crop insurance can change specialty crop growers’ production responses to climate and soil conditions. The moral hazard effect tends to increase the acreage and yield of the specialty crops, whereas the adverse selection effect tends to have the opposite effect. The overall effect of the FCIP on acreage and yield of specialty crops is found to be moderate.  相似文献   
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[目的]甘肃省农业气候资源丰富,适宜种植的杂粮作物品种较多,但其杂粮种业发展存在诸多与现代农业不相适应的问题,严重制约了杂粮产业的发展,因此急需提出针对甘肃省特色杂粮种业发展的策略。[方法]文章通过实地调研与文献分析,全面系统地分析了杂粮种业的特点和存在问题,并提出了甘肃省特色杂粮种业的发展策略。[结果]调研发现,甘肃省杂粮种子产值高达2亿元以上,其种子研发体系正在完善,商业化速度逐步加快,市场前景广阔。但仍存在杂粮种业缺乏长远规划,杂粮作物种子市场尚不健全,缺乏育繁推一体化的种子企业,种子信息网络及监管机制不健全;育种创新能力有待提高,品种布局不尽合理;杂粮作物品种保护意识不强,对知识产权重视程度不够等诸多问题。因此需要充分发挥甘肃省自然气候生态特点,挖掘优势特色杂粮作物,整合资源,构建杂粮作物育种创新技术体系;建立健全杂粮种子质量监控体制机制;培育现代杂粮种业龙头企业和现代化销售网络等发展策略。[结论]甘肃杂粮作物种业具有广阔的发展空间。  相似文献   
5.
We estimate the perceived costs of legal requirements (‘coexistence measures’) for growing genetically modified (GM) Bt maize in Germany using a choice experiment. The costs of the evaluated ex‐ante and ex‐post coexistence measures range from zero to more than €300 per measure and most are greater than the extra revenue the farmers in our survey expect from growing Bt maize or than estimates in the literature. The cost estimates for temporal separation, the highest in our evaluation, imply that the exclusion of this measure in Germany is justified. The costliest measures of the ones that are currently applied in Germany are joint and strict liability for all damages. Our results further show that neighbours do not cause a problem and opportunities for reducing costs through agreements with them exist. Finally, we find that farmers’ attitudes towards GM crops affect the probability of adoption of Bt maize. Our results imply that strict liability will deter the cultivation of Bt maize in Germany unless liability issues can be addressed through other means, for example, through neighbours agreements.  相似文献   
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Export agriculture offers potentially high returns to smallholder farmers in developing countries, but also carries substantial market risk. In this article we examine the intertemporal welfare impact of the timing of a farmer's entry into the export pineapple market in southern Ghana. We examine whether farmers who never cultivated pineapple are better or worse off than farmers who decided to adopt pineapple earlier or later relative to their peers and experienced a significant adverse market shock several years prior to our endline survey. We use a two‐stage least squares model to estimate the causal effect of duration of pineapple farming on farmer welfare. Consistent with economic theory, we find that earlier adoption of the new crop brings greater welfare gains than does later uptake. But we find that the gains to later uptake of pineapple—just before the market shock—are small in magnitude, just 0.1 standard deviations of a comprehensive asset index, indicating that the gains to adoption may be precarious and depend on the context, in particular on the severity of prospective market shocks.  相似文献   
9.
2000~2010年我国洪涝灾害损失综合评估及其成因分析   总被引:4,自引:0,他引:4  
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。  相似文献   
10.
进行林下经济作物认证,是保障食品安全的需要,有利于更好地开拓市场、促进农民增收,这也从根本上符合当前提倡的森林可持续发展战略,符合建立和谐林业生产体系的发展目标。对黑龙江省林区林下经济作物认证工作开展了调研,介绍了黑龙江省林下经济作物认证的研究进程、认证产品的选择及原因,同时对开展林下经济作物认证工作方面存在的问题进行了剖析,并且提出了相应的建议。  相似文献   
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