排序方式: 共有128条查询结果,搜索用时 31 毫秒
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吉林省西部半干旱区玉米节水高产高效研究 总被引:2,自引:0,他引:2
吉林省西部半干旱区在乾安和前郭县选用15hm2耕地采用滴灌灌溉、地膜覆盖、大垄双行、高产品种、合理施肥等一系列综合配套技术,变雨养农业为雨养农业和设施农业相结合的现代农业,达到了节水、高产、高效的目的。 相似文献
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The controversial Fast Track Land Reform Programme in Zimbabwe that redistributes commercially-owned farmland to smallholder households has caused concerns about the efficiency of agricultural production in the country. In this paper, we estimate the efficiency of resource use among smallholder farmers in Zimbabwe when producing maize, the staple crop in the country. Using both a semiparametric model and a fully parametric stochastic frontier model, we find significant production shortfalls for smallholder maize production. While labor, capital, and land all significantly affect the total output, the estimated mean efficiency score for farms with less than 10 hectares of land (A1) appears to be under 0.75, and for the entire sample (A1 and A2) it ranges between 0.595 and 0.772. There clearly exists a great potential for maize farmers to improve the technical efficiency and increase the total output. Gender and age of the household head, access to extension services, and activities of other crops significantly affect the technical efficiency of smallholder maize production in Zimbabwe. We also find that all farms operate under increasing returns to scale and that the technical efficiency score tends to increase with the level of output. 相似文献
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Paswel P. Marenya Christopher B. Barrett 《American journal of agricultural economics》2009,91(4):991-1006
Fertilizer interventions have attained prominence in rural poverty reduction programs in Africa. Using data from maize plots operated by small farmers in western Kenya, we find a von Liebig-type relationship between soil organic matter (SOM) and maize yield response to nitrogen application. Low SOM commonly limits the yield response to mineral fertilizer application. Although fertilizer is, on average, profitable in our sample, on roughly one-third of the plots degraded soils limit the marginal productivity of fertilizer such that it becomes unprofitable at prevailing prices. Moreover, because poorer farmers most commonly cultivate soils deficient in SOM, fertilizer interventions might be less pro-poor than is widely assumed and may instead reinforce ex ante income inequality. 相似文献
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This paper tests the ‘systems of innovation’ hypothesis for a selection of crops in Ghana and Burkina Faso that have shown significant growth in production over an approximately 20-year period. The question is whether such growth can only occur if supported by a system of innovation. Using two indicators (a common understanding on objectives and priorities, and a high level of interactivity), we find little evidence for the existence of anything that might be considered a high functioning system of innovation. 相似文献
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《国际农业可持续发展杂志》2013,11(4):290-304
Leguminous agroforestry (AF) species have been investigated and promoted in Malawi as a means to improve soil quality and maize (Zea mays) yields. Our objective was to determine whether AF systems' recommendations that solely consider impacts on average maize yields differ from those that include an analysis of production risk, profitability among different wealth groups and socioeconomic vulnerability. Employing participatory quantitative and qualitative on-farm research techniques, we investigated three AF-based maize/legume relay-cropping practices in southern Malawi. The perennial legumes included Sesbania sesban, Tephrosia vogelii and Cajanus cajan (pigeonpea). We found that AF species recommendations did diverge from those based solely on maximizing maize yields when incorporating risk, profitability and socioeconomic vulnerability as additional variables. For instance, the highest yielding system (the S. sesban/maize relay crop) was never recommended for the most vulnerable farmers based on the vulnerability analysis, and the cropping systems were often more profitable for the least vulnerable farmers than they were for the most vulnerable farmers. Cropping system recommendations based solely on obtaining the highest average maize yields would also have generally overlooked the economic and nutritional importance of pigeonpea, and the difficulty for the most vulnerable farmers to profit from fertilizers, potentially placing these farmers at greater risk. 相似文献
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小议玉米种子的贮藏方法及检查措施 总被引:1,自引:0,他引:1
玉米种子安全储藏的关键是提高入库质量,降低种子水分。玉米种子储藏有穗藏法和粒藏法两种,各地可根据气候条件、仓房条件和种子质量选择采用。相对湿度低于80%的地区以穗藏为宜,相对湿度超过80%的地区,则以粒藏为宜。那么,如何对玉米种子进行贮藏是至关重要的。实践证明,玉米种子的安全贮藏很重要,但也很难。为此,本文针对玉米种子贮藏技术进行简要探讨。 相似文献
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玉米秸秆和鸡粪混贮,可以生产质量较高的反刍动物饲料。这个途径改善了玉米秸青贮的发酵特性和产品品质,增加了玉米秸秆的营养成分,在减少资源浪费、产生很好的经济效益的同时,也能减少农业废弃物对环境的污染。 相似文献