甘肃省“121”雨水集流工程经济   总被引：1，自引：0，他引：1  

李莉 《中国农村水利水电》2007,(9):50-52

甘肃中东部地区地处黄土高原，气候干旱，水资源缺乏，农村人畜饮水困难。“121”雨水集流工程的实施，有效地解决了这些地区的人畜饮水困难。为了客观评价“121”雨水集流工程的经济效益和作用，利用建设项目后评价理论与方法，对工程的经济效益进行了科学评价，国民经济评价结果可行，其结果可用于指导全省雨水利用工程的规划、设计，加强雨水利用工作的决策、管理。  相似文献   

陆地棉品种间杂种F_2代优势研究及经济农艺性状的通径分析   总被引：6，自引：0，他引：6  

李煦远  吴红星  董彩虹 《棉花学报》1996,(3)

用７个Ｆ１代具高竞争优势的陆地棉品种间杂种Ｆ＿２代和高产、优质、多抗的品种鄂棉１５（对照）为材料，研究了Ｆ＿２代及皮棉产量等经济性状的竞争优势，又对它们与株高等在艺性状进行了通径分析。结果表明：正确选配亲本，能将高产、优质、早熟综合于一体，多代利用陆地棉品种间杂种。３８４×３６１Ｆ＿２，鄂荆１号（３２４７）×３６１Ｆ２显著优于对照，分别增产１５．４９％、１２．１６％，且纤维长度、早熟性与对照相近，在生产上有很大的利用价值。决定Ｆ＿２代皮棉产量主要是单株铃数、衣分以及它们之间的互作。同一农艺性状对不同经济性状影响程度很不相同，每个经济性状一般都受１～３个主要农艺性状和它们之间，或它们与其他农艺性状互作所制约。在湖北生态条件下，高产、优质、早熟的陆地棉品种间杂种Ｆ＿２代应具备棉抹较高，果位适中而果高偏低，纵横比较大，果枝夹角较小及主茎节距较大等农艺性状  相似文献   

THE OPTIMAL DECISTON OF ECONOMICAL DEVELOPMENT BY MARKOVIAN DECISION PROGRAMMING     

Yang Chunwei 《保鲜与加工》1988,(4)

This paper studies the tactics choice and its improvement in the development of economy by means of Markovian Decision Programming. An optimal decision and the maximum expected revenue can be obtained. The . paper also presents the procedures and formulas of numerical evaluation.  相似文献   

An Estimate on the Casual Relation between Financial Development and Economic Growth     

RAN Mao_sheng  ZHANG Zong_yi  FENG Jun 《保鲜与加工》2002,(3):123-129

This paper firstly discusses the relationship among money,real interest rate and economic growth of China. Then estimates the causality between financial development and economic growth by Bivariate Granger Casual Relation Test. The conclusion suggests that economic growth stimulate financial development more in China.  相似文献   

APPLICATION OF DECOMPOSITION COORDINATION METHOD OF LARGE - SCALE SYSTEMS AND METHOD OF NONLINEAR PROGRAMMING TO ECONOMIC SCHEDULING OF POWER SYSTEM     

Duan Yurong Tian Yufang 《保鲜与加工》1992,(6):112-118

In this paper,we discuss a mathematical mode) for optimization of active power dispatch of large-scale hydro-thermal power systems with cascaded hydropower stations. The following factors are taken into account: the variation of the head in the hydropower stations, water transport delay between cascaded stations etc. Using the decomposition-coordination method of large scale systems, we obtain a three-layer-hierarchical coordination system and a three-layer-hierarchical computational structure. We also discuss the computational methods which are used by each hierarchy. We have taken a test computation and analysing the result of an actual hydrothermal power system. The computational results show that it may obtain a satisfactory economic benefit. The paper provides some research work on the economic scheduling of hydrothermal power systems by the decomposition-coordination method of large-scale systems,multiplier method and a new variable metric method.  相似文献   

日光温室茄子冠气温差与环境因子之间的关系研究   总被引：6，自引：0，他引：6  

彭致功  杨培岭  段爱旺  何晖 《华北农学报》2003,18(4):111-113

系统地研究了日光温室内茄子冠气温差的变化规律与环境因子之间的关系,运用回归方法建立了主要气象因子与冠气温差之间的数量关系。深入分析了不同土壤水分条件下日光温室内茄子冠气温差与土壤含水量的关系,并建立了二者之间的相关方程,得出了诊断茄子水分状况的指标。  相似文献   

论乡村产业振兴   总被引：1，自引：1，他引：1  

黄国勤 《中国农学通报》2020,36(2):149-154

当前,全国上下正在全力推进乡村振兴战略的实施。乡村振兴,产业兴旺是重点。如何实现乡村产业振兴、产业兴旺,这是值得研究的紧迫而现实的重要问题。本文首先从乡村产业振兴在乡村振兴战略中的地位与作用入手分析,对新中国成立70年来中国乡村产业发展的历程进行了简要回顾,并将其划分为4个发展阶段：第一阶段：1949—1977年,传统产业缓慢发展;第二阶段：1978—2000年,乡镇企业异军突起;第三阶段：2001—2011年,新型产业不断涌现;第四阶段：2012年至今,乡村产业绿色“转型”。同时也指出了当前中国乡村产业存在的突出问题,即：产业门类少、生产规模小、产业层次浅、产业链条短、生产效率低、特色产业弱、品牌产业缺、产业环境差、产品质量低和缺乏竞争力。最后,针对上述存在的问题,提出了实施乡村振兴战略、实现乡村产业振兴要遵循的6大原则和10项具体措施,以期为推动实施乡村振兴战略做出积极贡献。  相似文献   

Welfare and environmental benefits of integrating commercially viable free-range broiler chickens into newly planted woodland: A UK case study     

Tracey Jones  Ruth Feber  Gabriel Hemery  Paul Cook  Katy James  Curt Lamberth  Marian Dawkins 《Agricultural Systems》2007

The commercial, welfare and environmental impacts of rearing small colonies of free-range chickens in newly planted woodland at two sites in the UK, during the first 2 years of the enterprise, were investigated. Newly planted rather than established trees were used so that commercially viable species could be planted in a way that would suit the management of the chicken enterprise, and small colonies were used so that farmers wishing to diversify could buy into the system progressively. It was anticipated that marketing a high specification product would provide an immediate income, whilst waiting for the future investment in trees to grow.  相似文献   

Environmental services and poverty reduction: Options for smallholders in the Sahel   总被引：1，自引：0，他引：1  

Petra Tschakert 《Agricultural Systems》2007

Environmental service provision is increasingly discussed as a potential new venue for the simultaneous pursuit of development and natural resource conservation objectives, particularly among landowners in the low-income tropics. To date, most of the experience with such market-regulated mechanisms comes from water and forest projects in Latin America. Preliminary evidence suggests that participation of, and benefits to, small-scale land users are highly unequal and that the synergistic goals of poverty reduction and resource conservation through these emerging market mechanisms might be overly ambitious. This paper assesses the possibility of pro-poor environmental service provision through carbon sequestration among smallholders in the Sahel. It focuses on a case study in the small-scale, rain-fed agricultural systems of the Old Peanut Basin of Senegal. Based on a conceptual framework including economic, institutional, policy and livelihood factors, it assesses to the extent to which specific groups of farmers are able or willing to participate in and benefit from potential carbon offset programs. Finally, the paper stresses the need for adequate and equitable financial support and a careful rethinking of the institutional structures necessary to enhance rural livelihoods and natural resource management in drylands, with or without market-based environmental service programs.  相似文献   

Evaluating a multi-level subsurface drainage system for improved drainage water quality   总被引：1，自引：0，他引：1  

J.W. Hornbuckle  E.W. Christen  R.D. Faulkner 《Agricultural Water Management》2007

This paper describes a multi-level drainage system, designed to improve drainage water quality. Results are presented from a field scale land reclamation experiment implemented in the Murrumbidgee Irrigation Area of New South Wales, Australia. A traditional single level drainage system and a multi-level drainage system were compared in the experiment in an irrigated field setting. The single level drainage system consisted of 1.8 m deep drains at 20 m spacing. This configuration is typical of subsurface drainage system design used in the area. The multi-level drainage system consisted of shallow closely spaced drains (3.3 m spacing at 0.75 m depth) underlain by deeper widely spaced drains (20 m spacing at 1.8 m depth). Data on drainage flows and salinity, water table regime and soil salinity were collected over a 2-year period.  相似文献