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1.
This paper uses the Malmquist index to examine the sources of Total Factor Productivity (TFP) in Chinese agriculture. The overall goal of this study is to create a framework for assessing the trend of China’s agricultural infrastructure and to measure its impact on Total Factor Productivity. The main methodological contribution is to provide more contributive measure of crop-specific technologies. Based on the province-level panel data set during 1988–2002, the primary finding is that infrastructure has positively and statistically significant association with the estimated coefficient on Total Factor Productivity for rice, wheat, maize, and bean. An erratum to this article is available at .  相似文献   
2.
In the oligopsony market, farmers may receive low prices and policy analysis assuming perfect competition can yield serious bias results. In this paper, we estimate oligopsony power between processors and farmers and evaluate the welfare impact of the paddy pledging program (PPP), a generous price support program in the Thai Jasmine rice market, with an imperfect competition model. We develop a model that consists of rice supply equation and derived demand equation. We then simultaneously estimate these equations using system estimation methods to recover oligopsony power parameters. Finally, we use these parameters to assess the welfare impact of the price support program. Using annual panel data running from crop marketing year 2001/2002–2015/2016 and exploiting the institutional feature of the PPP, we find strong evidence of some oligopsony power, a moderate level of oligopsony price distortion, and a negative relationship between price support and oligopsony power. We also find that the PPP is inefficient but effective in income redistribution. Moreover, the program benefits both farmers and consumers. With better policymaking decisions, the PPP can be efficient by setting a suitable support price. Therefore, our results show that in the case of the Thai Jasmine rice market, the generally accepted “wisdom” about agricultural price support policy does not necessarily hold, and price support can be designed to improve the efficiency of the market.  相似文献   
3.
长久以来,前辈学人对于《史记》中平阳君赵豹“秦以牛田(之)水通粮”一语解释多有不同,或以为是秦“以牛耕田,以水漕粮”,或以为是秦“以发源于‘牛田’之地的河流进行漕粮”,但均未形成定论。本文认为,先秦时期关中水资源丰富,渭河支流多可航运,加上关中水利发达,于是秦国利用与渭河支流连通的田间大渠——“浍”渠进行粮食漕运,即所谓“秦以牛田水通粮”。且战国后期,随着秦对外战争规模的扩大,粮秣耗费日增,使用“牛田水通粮”已十分必要。  相似文献   
4.
We employ a non‐parametric approach, data envelopment analysis, to estimate the technical and irrigation efficiency of rice farms in the Punjab Province of Pakistan. We use a cross‐sectional dataset of 80 rice growers, including 45 tube‐well owners and 35 water buyers. Mean technical efficiency scores show that tube‐well owners and water buyers are operating at fairly high efficiency levels, indicating that access to technology is not a major constraint. However, irrigation inefficiency is pronounced, with water buyers being more inefficient than tube‐well owners. A bootstrap truncated regression is used to investigate the determinants of technical and irrigation efficiency. We suggest that groundwater management policies should be designed to address efficiency enhancing factors such as knowledge of crop water consumption requirement, better credit opportunities, outreach extension services and training programs.  相似文献   
5.
日本稻作生态农业发展途径与模式   总被引:1,自引:0,他引:1  
刘星辰  杨振山 《经济地理》2011,31(11):1891-1896
生态农业通过农业与自然环境以及社会经济的平衡,实现农业的可持续发展,是未来农业发展的重要方向之一.水稻是日本重要农作物之一,也是我国农业的重要组成部分.通过回顾和总结日本稻作生态农业的发展途径与模式,尤其是在稻鸭(鱼)共作等有机农业生态模式、农业耕作技术和水稻多功能性方面所取得的成就的基础上,为我国水稻生态种植生产提供参考和建议.  相似文献   
6.
稻谷市场供求分析   总被引:1,自引:0,他引:1  
近年来全球气候变化异常,粮食生产受到自然灾害影响,在一定程度上影响了供求关系,增加了人们对"粮食危机"的预期。作为全球种植生产和消费需求最广泛的粮食作物,稻谷与人们生活最为密切,稻谷的国际及国内市场供求日益受到人们的关注。本文以稻谷市场供求为研究对象,分析稻谷历年生产状况,探讨稻谷的消费情况,对稻谷市场供求形势及趋势进行分析。  相似文献   
7.
黄石市基本农田水稻中重金属污染评价分析   总被引:1,自引:0,他引:1  
对黄石市基本农田稻米中重金属含量进行了分析测定并进行相应的分析评价,以明确该地区稻米中的重金属污染情况。结果表明:基本农田稻米整体上已经受到了Pb污染,大冶市和阳新县的稻米均为重度Pb污染(污染指数分别为5.469和3.689),未受到其他重金属污染(其他重金属的污染指数均小于1);分析不同样点的污染情况,62%的样点为重污染水平,18%的样点为中污染水平,16%的样点为轻污染水平,其他为清洁水平;分析污染原因可能主要由废水浇灌以及大气重金属尘沉降等引起。  相似文献   
8.
Regional differences in total factor productivity, efficiency, and technological change in the Philippine rice sector are examined for the post-Green Revolution era. Malmquist productivity indices were constructed for 1971–90 and were decomposed into efficiency and technological change. The average annual Malmquist productivity growth was only slightly positive. Productivity growth was negative during the early 1970s, and was followed by a period of positive growth. Growth was negative again in the late 1980s. The period of positive growth coincided with the introduction of new rice varieties while the declines are likely to have been caused by intensification of rice production in lowland farming systems. Certain regions such as Central Luzon, Western Visayas, and Southern and Northern Mindanao had higher rates of technological change than others. This may be due to higher investments in infrastructure and education, increased adoption of tractors, and a better agroclimatic environment.  相似文献   
9.
气候变化与黄河中下游地区的早期稻作农业   总被引:1,自引:0,他引:1  
随着中国全新世大暖期的到来,黄河中下游地区迎来了温暖湿润的气候环境,这为农业生产提供了前所未有的优越条件。虽然黄河中下游地区是以旱作农业为主体的,但在粟作农业发展的同时,稻作农业也在孕育发生。从距今七八千年的裴李岗文化时期直到夏商时代,尽管其间气候状况发生过冷暖波动,稻作的发展也存在有起伏变化,但在整个全新世大暖期,稻作农业基本上都在逶迤发展着。实际上在全新世大暖期存在着一个粟稻混作区,其范围随着气候变化虽在不断波动,但大体位置在黄淮之间。这与黄河中下游地区所处的南北生态过渡带的地理环境密不可分,也是南北文化交流的重要体现。从裴李岗文化时期到夏商时代的早期稻作农业,也经历了一个发生、发展的演变过程,它对黄河流域的古代农业及社会发展产生了深远的影响,也充分显示了气候变化对农业和社会发展的重要影响及作用。  相似文献   
10.
采用重金属镉富集装置对被测糙米进行先碳化后灰化的处理,使得被测糙米中的镉元素富集;将得到的被测糙米灰分放入样品杯中压制成被测样品,由X射线荧光分析装置进行测量,得到镉元素的信号强度,然后根据信号强度与浓度的比例关系自动计算样品中镉的含量.整个分析过程在15 mim以内,数据结果与AAS结果一致。  相似文献   
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