نتایج جستجو برای: low efficiency irrigation

تعداد نتایج: 1566921  

Journal: :Environmental monitoring and assessment 2006
J Causapé D Quílez R Aragüés

The review analysis of twenty two irrigation efficiency (IE) studies carried out in the Ebro River Basin shows that IE is low (average IE)(avg)(= 53%) in surface-irrigated areas with high-permeable and shallow soils inadequate for this irrigation system, high (IE)(avg)(= 79%) in surface-irrigated areas with appropriate soils for this system, and very high (IE)(avg)(= 94%) in modern, automated a...

2017
Qing Zhou Xiangzheng Deng Feng Wu Zhihui Li Wei Song

Water has become increasingly scarce in northwestern China due to climate change, economic growth and burgeoning population. Improving agriculture water use efficiency is of strategic significance in promoting socio-economic water productivity for arid and semi-arid inland river basins. Based on the household-level data collected in Zhangye City, which is located in the middle reaches of Heihe ...

2010
Mingyao Zhou Susheng Wang Zhen Zhang Lidong Chen

It is necessary to research a cheap and simple fixed water distribution device according to the current situation of the technology of low-pressure pipe irrigation. This article proposed a fixed water distribution device with round table based on the analysis of the hydraulic characteristics of low-pressure pipe irrigation systems. The simulation of FLUENT and GAMBIT software conducted that the...

2015
J. Jägermeyr D. Gerten J. Heinke S. Schaphoff M. Kummu W. Lucht

Global agricultural production is heavily sustained by irrigation, but irrigation system efficiencies are often surprisingly low. However, our knowledge of irrigation efficiencies is mostly confined to rough indicative estimates for countries or regions that do not account for spatiotemporal heterogeneity due to climate and other biophysical dependencies. To allow for refined estimates of globa...

Journal: :آب و خاک 0
سید اسداله محسنی موحد محمود اکبری

abstract due to limited water resources in agriculture, application of each strategy to economize water use and increase area under cultivation is very important. one such strategy is deficit irrigation. for optimal planning of deficit irrigation, it is necessary to determine different sensitive stages of plant water shortages. in this study the effect of deficit irrigation on growth and yield ...

2004
BRADLEY A. KING JEFFREY C. STARK DENNIS C. KINCAID

I ncreasing production efficiency is becoming a major theme for producers in order to maintain or increase their economic return in an increasingly competitive global market. In the case of irrigated agriculture, producers must also address increasing public concern about water conservation, water quality, and environmental protection. Two irrigation management issues require attention in order...

Journal: :مدیریت آب و آبیاری 0
عبدالصمد کاغذلو دانشجوی کارشناسی ارشد گروه مهندسی آبیاری و زهکشی، دانشگاه بین المللی امام خمینی(ره)، قزوین عباس ستوده نیا دانشیار دانشگاه بین المللی امام خمینی(ره)، قزوین پیمان دانش کار آراسته دانشیار دانشگاه بین المللی امام خمینی(ره)، قزوین

evaluating the performance of irrigation systems by providing the possibility of increasing irrigation efficiency in those systems is an important factor in the field of water resources management. in this study, the performance of three systems were evaluated, including linear move sprinkler irrigation systems in maize, sugar beet and alfalfa fields of magsal agro-industrial company which is l...

2008
A. J. Clemmens C. M. Burt

Evaluation of actual irrigation system perfonnance should rely on an accurate hydrologic water balance over the area considered. In a companion paper, water uses are categorized as consumptive or noncon­ sumptive, and beneficial or nonbeneficial. Real perfonnance is based on water uses over a specified period of time, rather than observation of a single irrigation event (with associate potentia...

2017
Yi-Bo Li Yan-Wei Fan Ye Liu Xiao-Yi Ma

Film hole irrigation is an advanced low-cost and high-efficiency irrigation method, which can improve water conservation and water use efficiency. Given its various advantages and potential applications, we conducted a laboratory study to investigate the effects of soil texture, bulk density, initial soil moisture, irrigation depth, opening ratio (ρ), film hole diameter (D), and spacing on cumu...

Journal: :چغندرقند 0
شجاعت زارع اعضاء هیئت علمی مرکز تحقیقات کشاورزی و منابع طبیعی خراسان رضوی حسنعلی شهبازی اعضاء هیئت علمی مرکز تحقیقات کشاورزی و منابع طبیعی خراسان رضوی

in ordet to investigate economic efficiency of five cultural systems in sugar beet crop, including high input, medium input  low input , high  and medium inputs without 3 times irrigation after emergence, an experiment was conducted over  two years  (2002-2003) in agricultural and natural resources research center of khorasan. these systems were analysed by marginal analysis and  linear program...

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