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1.
Practices that minimize the rate of soil degradation, increase crop yields and raise farm income are key to sustaining agricultural productivity in the hills of Nepal. The use of farmland is undergoing rapid changes in response to increasing population pressure, deforestation and subsistence needs. Against this background, this study examined the impact of an agroforestry intervention project on farm income based on a sample of subsistence farm households in Dhadhing district. The project was implemented by Nepal Agroforestry Foundation in 1993/94 to increase fodder production through the promotion of agroforestry. A total of 223 households (82 with project and 141 without project) were interviewed during May–October 1998 to collect information on production and agroforestrys' impact on farm income. The benefit-cost analysis showed that the agricultural system including agroforestry was more profitable than the conventional one. The results also showed that the introduction of mulberry trees for sericulture could further enhance the profitability of an agroforestry-based system. Thus, agroforestry has great potential for enhancing food production and farmers' economic conditions in a sustainable manner through its positive contributions to household income.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   
2.
In this paper, we estimate the costs and benefits of implementing the proposed National Organic Program for laying hens compared with alternatives. For the regulatory proposals under option 2, the regulatory cost will be zero because most producers are already in compliance with the proposed regulation. The anticipated benefits of this regulation will be zero as well, because the current market prices already reflect consumers’ willingness to pay for the existing animal welfare conditions. For the regulatory proposals under option 3, before market adjustments, the average regulatory burden for the entire organic egg industry will amount to $0.09 per dozen eggs, with extreme variations between $0 for small operations and $2.30 per dozen for large operations. If we rely on the average price of organic eggs, $2.69 per dozen, and assume a maximum estimated benefit associated with improved animal welfare conditions, that consumers would be willing to pay of about 30% above the current market price, the estimated benefit of regulation amounts to $0.81 per dozen eggs. Based on the findings, we conclude that option 2 is welfare neutral and could be easily adopted because it already has been adopted by representative producers. For option 3, the benefit-cost ratio is larger than 1, which indicates that the proposal passes the benefit-cost ratio test. The obtained result, however, has to be interpreted with serious reservation because of the differential effect that the proposed regulation would have on different industry participants. Under option 3, the effect of the proposed changes on small organic egg producers is negligible because most small producers are operating under conditions similar to the proposed living standards. However, costs will increase substantially for large organic egg producers and likely cause a substantial number of producers to exit organic production and switch to conventional production, which would cause a substantial decline in the prices of conventional eggs and organic feed in the short run.  相似文献   
3.
Modern nursery methods of seedling production in different sized root trainers,were compared by raising seedlings of Pinus wallichiana involving costs incurred and benefits received. In order to provide a common basis for the comparisons,the study involved the raising of 1000 seedlings annually on a continuous basis for seven years. A relative economic analysis of raising P. wallichiana seedlings in 300,150 and 100 cm3 root trainers was carried out and we estimated that the root trainers of 300 cm3 capacity...  相似文献   
4.
不同稻田综合种养模式的成本效益分析   总被引:6,自引:1,他引:5  
为获知和分析稻田综合种养模式在中国的发展现况及存在问题,根据2013年中国4个省份两种主要稻田种养模式的调查数据,采用Kruskal—Wallis非参数检验等方法分析了不同稻田种养模式在生产投入、经济效益上的差异以及在化肥、农药减量等方面的效应。结果显示,稻田综合种养具有较好的经济和生态效益,稻蟹、稻鱼两种种养模式的平均利润为水稻单作的2.43~3.92倍,化肥成本减少2.8%~49.2%,农药成本减少3.2%~83.6%,但技术成熟度及产业化程度的差异使种养户在最终经济收益及生态效益上的极差较大。研究表明,中国稻田综合种养规模化程度不够、成本投入偏高、综合种养生态、社会效益提升有限是目前面临的主要问题,因此加大政府的扶持力度,加强种养关键技术的研究,因地制宜将规模化的现代农业与传统稻田种养相结合是解决这些问题的关键。  相似文献   
5.
An experiment upon an agri-silvicultural system involving Willow (Salix alba) tree, Kale (Brassica oleracea var. acephala) and Knol khol (Brassica oleracea var. caularapa) was laid in randomized block designed at farmers’ willow field at Shalimar near Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, Srinagar India during 2005 and 2006. The main plot was divided into sub-spots with 8 m × 2 m in size each in which four two-year-old willow (Salix alba) trees were at a spacing of 2 m × 2 m in a sub-spot. The intercrops were maintained at recommended spacing and supplied with recommended doses of fertilizers. The benefit-cost ratio in willow plantation intercropped with vegetable crops of Kale and Knol Khol was analyzed and compared with the benefit-cost ratio of sole willow tree forestry. The results showed that every rupee invested in plantation of agri-silvicultural system generates benefit-cost ratio of 2.78 and 2.79 in case of Willow intercropping with Kale and Willow with Knol khol, respectively, while as for sole crop of willows benefit-cost ratio was calculated to be 2.66. These results provided circumstantial evidence in favour of adopting agroforestry involving willow instead of Sole tree forestry.  相似文献   
6.
The government of Zimbabwe uses agricultural development as one of the ways to stimulate economic growth. Agriculture in Zimbabwe is characterized by a dual agrarian system comprising the large scale commercial sector and the smallholder communal sector. The communal sector, 47 percent of the country, supports more than 70 percent of the population. One strategy used to improve agricultural performance is the development of agricultural infrastructure. Of the 117, 830 ha developed for irrigation only slightly more than 6 percent is in the communal (smallholder) sector. The smallholder irrigation systems are managed under four different systems, namely the government-managed Agritex, farmer-managed community, the informal bani (dambo) managed by farmers and the ARDA outgrowers managed jointly by a parastatal and farmers. This paper evaluates the benefits and costs associated with these different management systems. Benefit-cost ratios are computed for each system. The bani system achieves higher benefit-cost ratios than the community, which achieves higher ratios than the Agritex management system. This indicates that the government should consider using the community system for developing the potential 93,000 ha of communal smallholder irrigation systems. It should also seriously consider the bani system as an alternative development strategy.  相似文献   
7.
讨论用 IRR 和 B/C 指标进行水利工程多方案评价的结果。对于确定的经济分析期和投资标准收益率这两个指标的评价结果同样有效。  相似文献   
8.
Many threatened and endangered species are negatively impacted by predation. Management of the predators that are geographically and temporally in position to threaten species of concern can greatly aid in their conservation. However, decisions on management strategies are based within economic constraints, while the success of management actions is measured by wildlife resource improvement. Here, we review methods for applying monetary valuations for threatened and endangered species so that economic analyses of management actions can be used to help guide and evaluate management decisions. A variety of applied examples are provided to demonstrate the principles. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
9.
In the current paper, we estimate the costs and benefits of implementing the proposed rule for changes in living conditions for organic broilers. In contrast to the effects of the proposed rule for changes in living conditions for laying hens, the effects of the rule on organic broilers is anticipated to be relatively limited. All producers are already in compliance with option 2 of the rule, and changes required under option 3 are minimal for most producers. Using the per-farm estimated regulatory costs and the estimates of production volumes and actual prices, the total estimated annual industry cost under option 3 is $2.4 million, which represents 0.1% of total industry revenue. The estimated benefits associated with this type of perceived animal welfare improvement are high enough to cover the anticipated cost, and the proposed option easily passes the benefit-to-cost ratio test.  相似文献   
10.
Natural monopoly is characterized by economies of scale and production cost subadditivity in the traditional and new theory of natural monopoly.The paper thinks that they are incorrect in the method of judging some industry as natural monopoly.They neglect some important transaction(system) cost factors.Once giving up the old analytic framework, the authors find that economies of scale and production cost subadditivity are neither necessary nor sufficient for natural monopoly.Based on the analysis on weaknesses of the traditional and new theory of natural monopoly,the paper discusses the essential character of natural monopoly and educes some corresponding revelations about the reform of network industries.  相似文献   
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