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1.
P. Banik 《Journal of Agronomy and Crop Science》1996,176(5):289-294
A field experiment was conducted during the winter season of 1992–93 and 1993–94 at Agricultural Experimental Farm, Giridih, Bihar to evaluate the intercropping systems of legumes, gram ( Cicer arietinum L.), pea ( Pisum sativum ) and lentil ( Lens culinaris ) with wheat ( Triticum aestivum ) in 1:1 and 2:1 'row replacement series'. Intercropping systems were assessed on the basis of new indices termed as actual yield loss (AYL) and intercropping advantage (IA). This paper highlights the comparative effectiveness of evaluating the intercropping systems through the existing intercropping indices like LER, RCC, aggressivity. The indices AYL and IA seem to be more appropriate particularly when per plant yield is considered. Intercropping reduced the yield of component crops compared with respective pure stands. Wheat + pea in 1:1 row replacement series gave the highest wheat yield equivalent value (3.02 t ha−1 ) followed by wheat + lentil (2.91 tha−1 ). When the actual sown proportion was considered wheat + lentil (1:1) resulted in maximum AYL (+0.610) and IA (+0.279) values. This treatment also gave the maximum monetary advantage (Rs 5985.45 ha−1 ). 相似文献
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P. Panigrahi R. K. Sharma S. S. Parihar M. Hasan D. S. Rana 《Irrigation and Drainage》2013,62(1):67-73
The profitability of regulated deficit irrigation (RDI), sustained deficit irrigation (SDI), and SDI with partial root zone drying (PRD) strategies was compared to that with full irrigation (FI: 100% crop evapotranspiration) in drip‐irrigated Kinnow mandarin in northern India. RDI was scheduled with two irrigation levels: no irrigation and 50% crop evapotranspiration (ETc.) imposed in the early fruit growth period (EFGP) and final fruit growth period (FFGP) singly and in combination, whereas SDI was scheduled at 50% ETc and 75% ETc with and without the PRD technique. The highest fruit yield was recorded with FI, which was statistically on a par (p > 0.05) with that with SDI at 50% ETc with PRD (PRD50). Economic‐based comparison shows that all the treatments were economically viable since their profitability (net return, INR 137 000–1 300 000 ha‐1 and benefit–cost ratio, 2.1–14.3) were viable. The net return generated with PRD50 was statistically (p > 0.05) at par with that generated with FI. However, the benefit–cost ratio and economic water productivity calculated with PRD50 were found to be significantly (p < 0.05) higher (36 and 87%, respectively) than that with FI. These results lead us to conclude that the PRD50 strategy could be used to improve irrigation water productivity substantially in commercial Kinnow mandarin orchards in sandy loam soil. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
4.
水是城市发展中的重要资源,杭州社会经济的快速发展对水资源的量与质都提出了新要求。为此,通过调查杭州水资源的现状,分析了杭州城市发展与水资源的需求矛盾,就解决两者之间矛盾以下促进杭州经济、社会、环境等可持续性发展提出了几点建设性对策。 相似文献
5.
Summary A commercial horticultural industry that establishes plant-breeding nurseries for an exotic species throughout a regional economy will expand until the marginal profit of the last nursery established is zero. However, a regional government concerned with social welfare will take into account not only the profits of the horticultural industry but also any expected costs of an accidental invasion. The latter costs will consist of the discounted expected social damages due to an increase in the rate of invasion over time and the increase in expected damage cost per hectare caused by an additional nursery. A government can employ an “introducers' pay” tax equal to the latter social costs to ensure that the plant breeding industry establishes the optimal number of nurseries. We illustrate this outcome with the example of purple loosestrife (Lythrum salicaria) in North America. In the absence of any tax, the horticultural industry will establish n = 3528 nursery operations, and the expected damages from invasion are US$ 28.2 million per year. With the tax, only n = 300 nurseries are established but the expected damages from invasion are reduced to US$ 1.3 million per year. Although profits for the horticultural industry are lower from the tax, the net gains in overall social welfare more than offset the losses. Although these results are illustrative only, they show that the problem of plant invasives initiated by commercial operations is amenable to standard economic analysis and solutions, such as implementation of an “introducers' pay tax”. 相似文献
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分析了非会计专业和会计专业的教学差异,在此基础上提出了提高农林经济管理专业的会计学课程教学效果的几点建议。旨在通过改进和调整课程教学方法和策略,培养符合专业要求的专门人才,构建符合特点的教学模式。 相似文献
8.
农特产品是一种特殊的产品，体现在名气较大，与传统文化关系密切，涉及范围广泛，与农民生活息息相关等方面。从品牌形象的角度着手，提出对农特产品进行品牌形象建构。针对农特产品中普遍存在的品牌老化、品牌形象设计水平较低、不重视品牌经营等问题提出对品牌形象建设要有长期规划，深入挖掘农特产品的传统文化因素进行整体形象设计，在推广与宣传方面采用企业＋基地＋农户的模式，群策群力，搞好农特产品品牌形象的经营工作，为农特产品产业化及市场开拓做出贡献。参10 相似文献
9.
选取SCI/SSCI收录的国际"农业经济与政策"领域中的10个英文期刊作为研究基础数据,对作者发表论文及合作进行研究。发现作者发文量分布出现明显的"长尾现象",服从幂律分布规律,即少量作者和机构对学科领域的发展做出了大量的贡献,而大量的作者和机构只做出了少量贡献。农业经济与政策领域合作网络中包含大量不相连接的小型网络,处于科研合作网络发展的初级阶段。 相似文献
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