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1.
In this article we adapt Burtless and Hausman's (1978) methodology in order to estimate farmers' demand for irrigation water under increasing block-rate tariffs and empirically assess its effect on aggregate demand and inter-farm allocation efficiency. This methodology overcomes the technical challenges raised by increasing block-rate pricing and accounts for both observed and unobserved technological heterogeneity among farmers. Employing micro panel data documenting irrigation levels and prices in 185 Israeli agricultural communities in the period 1992–1997, we estimate water demand elasticity at −0.3 in the short run (the effect of a price change on demand within a year of implementation) and −0.46 in the long run. We also find that, in accordance with common belief, switching from a single to a block-price regime, yields a 7% reduction in average water use while maintaining the same average price. However, based on our simulations we estimate that the switch to block prices will result in a loss of approximately 1% of agricultural output due to inter-farm allocation inefficiencies.  相似文献   
2.
农田水利设施建设的成功取决于有效的制度保障,而有效的制度安排则取决于"基础设施属性—参与者特质—制度环境"三个要素之间的匹配,中国古代农田水利设施的发展历程便证明如此。对于中国新时期的农田水利设施建设,本文提出相应的制度安排,即大型灌区灌溉设施的集权型制度、小型灌溉设施的农民自治制度以及类经济自立型排灌区的混合型制度安排。  相似文献   
3.
中国封建时期农田水利设施建设绩效辉煌,其中制度起到非常重要的作用。历史上农田水利设施的发展经过了三个波动的阶段,产生了集权型、自治型和混合型三种制度安排与制度变迁,这些制度分别保证了与其相适应的设施建设绩效和灌溉绩效。中国封建时期农田水利设施建设与治理的制度变迁,为今天建立社会主义新农村和实现农业的可持续发展具有重要的启示意义。  相似文献   
4.
Modern irrigation technologies have been suggested as a means of conserving scarce water and reducing environmental pollution caused by irrigated agriculture. This paper applies an economic model of technology selection that provides a general framework to analyzing adoption of irrigation technologies under various environmental conditions. Data from the San Joaquin Valley of California is used to verify the theoretical relationships. Results suggest key variables to be considered by policy makers concerned with adoption of modern irrigation technologies. Among these variables are crop prices, water technology costs, farm organization characteristics, and the environmental conditions of the farm or the field. Policy implications were discussed and analyzed.This research was conducted while the first author was a visiting scholar with the Dept. of Agricultural Economics, University of California, Davis, and USDA-ERS, USA.  相似文献   
5.
城市边缘区大型公共设施的规划   总被引:4,自引:2,他引:4  
程文  赵天宇 《城市问题》2003,(1):29-31,19
本文从大型公共设施在边缘区发展的影响因素入手 ,借鉴、分析国外的经验和教训 ,研究大型公共设施的建设与城市演变的关系 ,提出大型公共设施的建设应从城市发展战略、城市交通体系与政策、城市经济与环境以及城市建筑设计等多角度进行综合一体化规划设计 ,并以此促进城市重要建设项目的规划选址、规模布局、建筑计划等工作程序进一步规范和完善  相似文献   
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7.
张伟 《价值工程》2014,33(33):99-100
水库灌区的建设是我国农业发展中十分重要的一环,它关系到灌区覆盖范围内的农作的收成。本文将结合灌区建设中工程管理工作当中出现的一些问题和现状进行探讨,希望能够对现在的灌区建设管理起到积极的作用。  相似文献   
8.
In this paper we compare conceptualising single factor technical and allocative efficiency as indicators of a single latent variable, or as separate observed variables. In the former case, the impacts on both efficiency types are analysed by means of structural equation modeling (SEM), in the latter by seemingly unrelated regression (SUR). We compare estimation results of the two approaches based on a dataset on single factor irrigation water use efficiency obtained from a survey of 360 farmers in the Guanzhong Plain, China. The main methodological findings are that SEM allows identification of the most important dimension of irrigation water efficiency (technical efficiency) via comparison of their factor scores and reliability. Moreover, it reduces multicollinearity and attenuation bias. It thus is preferable to SUR. The SEM estimates show that perception of water scarcity is the most important positive determinant of both types of efficiency, followed by irrigation infrastructure, income and water price. Furthermore, there is a strong negative reverse effect from efficiency on perception.  相似文献   
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10.
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   
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