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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
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《Food Policy》2016
Nepal’s population continues to grow, but the agricultural sector’s performance remains almost stagnant. This has led to a decline in the per capita availability of food. Increasing agricultural productivity is the key to agricultural growth, and one strategy for increasing agricultural productivity is to use improved seeds. This study investigates the impact of contract farming (CF) in high yielding varieties (HYV) of paddy seed production on costs, yield, and profits of smallholder farms in Nepal. Using farm-level data and a non-parametric propensity score matching estimator, the study finds a significant positive impact of contract HYV seed farming on revenues, profits, and yield, and a significant negative impact on total costs of production. Additionally, very small farms (⩽0.43 ha) with CF in HYV paddy seeds tend to gain the most when it comes to yield per hectare. Our estimates reveal that the average smallholder household in Nepal engaged in CF with input conditions receives higher profits. However, farmers engaged in CF with output conditions tend to have higher yields but smaller profits. Finally, farmers engaged in CF in HYV paddy seeds with both input and output conditions have the highest yield gains and significantly higher profits. 相似文献
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Manu E. Saunders 《国际农业可持续发展杂志》2016,14(1):82-99
Homogenization of agricultural landscapes affects ecological processes and biodiversity and can affect the community composition of ecosystem service providers. These effects can have particular impact in landscapes dominated by monocultures of pollinator-dependent tree crop plantations, which create both spatial and temporal homogeneity at the landscape scale. I looked for associations between the proportion of nearby unmanaged vegetation and potential wild pollinator groups collected within flowering almond orchards in two types of landscape. In the Complex landscape, characterized by a heterogeneous mosaic of multiple crops, semi-natural grassland and natural woodland, insect pollinator groups were not associated with unmanaged vegetation. In the Simple landscape, dominated by monoculture almond plantations, most pollinator groups showed positive relationships with the two unmanaged vegetation types (grassland and woodland). In particular, all wild bee and all but one hoverfly individual were found in remnant native vegetation patches within almond plantations, rather than within rows of almond trees. More research is necessary to identify how structural differences created in monoculture landscapes, between crops and the native vegetation they encroach on, influence ecological communities and the provision of ecosystem services. 相似文献
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我国农业野生植物资源原生境保护区建设现状、问题及未来的思考 总被引:1,自引:0,他引:1
我国农业野生植物原生境面临着环境污染、人类农业生产、经济社会发展以及各类违法活动的侵蚀和破坏,建立原生境保护区是保护农业野生植物资源的重要途径之一。基于对当前威胁我国农业野生植物原生境面临的四大因素(自然灾害、农业活动、经济发展、违法活动)的系统梳理的基础上,探讨了现有农业野生植物原生境保护区建设的法规政策体系以及保护区建设现状和存在的主要问题,在此基础上提出了加强保护区建设的几点建议。分析结果表明,当前我国农业野生植物保护区建设存在的主要问题包括:保护区土地权属界定、保护区建设内容限定过窄、忽视保护区管理机构能力建设、对保护区周边农民权益保护不够。为了提高保护区建设工作,文章建议相关部门应该重视以下几个问题:统筹协调行业部门之间的权属差异,重视农业野生植物异位保存工作,修订完善保护区建设技术规范,兼顾保护区民众利益。 相似文献
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Factors affecting subjective well-being and their gross effect measurement have been widely studied. However, how people derive utility from these factors has not been fully explored. This article provides a way to decompose the gross effect of major determinants on life satisfaction into direct and indirect effects and make inference for the latter. Because the indirect effect is nonlinear in parameters associated with different models in an equation system, it creates a problem in estimating the standard error. Besides, the categorical nature in survey data further introduces bias to the covariance estimation even asymptotically. To address these issues without knowing the form of heteroskedasticity under the null hypothesis, we propose to extend the wild bootstrap procedure in this particular context. Its robustness against various data properties is validated via several simulation experiments. Using three recent waves of World Values Survey, we find that the relative importance of life control has significantly increased recently, and endowing citizens with the right to enjoy their freedoms and liberties is a more effective policy in raising life satisfaction than promoting national income. 相似文献
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We examine the quantile serial dependence in crude oil prices based on the Linton and Whang’s quantile-based portmanteau test which we improved by means of quantile wild bootstrapping (QWB). Through Monte Carlo simulation, we find that the quantile wild bootstrap-based portmanteau test performs better than the bound testing procedure suggested by Linton and Whang. We apply the improved test to examine the efficiency of two crude oil markets – WTI and Brent. We also examine if the dependence is stable via rolling sample tests. Our results show that both WTI and Brent are serially dependent in all, except the median quantiles. These findings suggest that it may be misleading to examine the efficiency of crude oil markets in terms of mean (or median) returns only. These crude oil markets are relatively more serially dependent in non-median ranges. 相似文献