نتایج جستجو برای: Soil water uniformity

تعداد نتایج: 705692  

2015
Kai Huang Desuo Cai Jinchuang Guo Wei Pan

A laboratory soil column experiment was first conducted to analyze water movement in latosol of sugarcane field under drip irrigation from single-point source at different emitter discharge rates. Next, a mathematical model of soil water movement under drip irrigation from single-point source was built using Hydrus-3D, which could accurately simulate the shape of the wetted soil volume and the ...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه شیراز - دانشکده علوم 1392

gol-e-gohar iron ore mine of sirjan in southern part of iran is a large open pit that operates below the groundwater table and during mining operation, dewatering is required to prevent operation processes from flooding. current operation is going on by digging wells in or out of the pit and pumping to prevent flooding. as a result of the former dewatering operation a vast deep cone of depressi...

Journal: :journal of agricultural science and technology 2014
h. ebrahimian e. playan

high efficiency and uniformity of water and fertilizer application are usually, considered as the ultimate goals of an appropriate design and management of irrigation and fertigation systems. the objective followed in this paper was to present a simulation-optimization model for alternate vs. conventional furrow fertigation. two simulation models (surface fertigation and swms-2d models) along w...

2007
José O. Payero

Subsurface drip irrigation (SDI) applies water directly to the crop root zone using buried polyethy­ lene tubing, also known as a dripline, dripperline, or drip tape (Figure 1). Driplines come in varying diam­ eters and thicknesses in order to maintain acceptable irrigation uniformity for different field lengths. Smaller diameter driplines are used when short lateral lengths are required. As la...

2015
Ioannis Gravalos Dimitrios Kateris Anastasios Georgiadis Theodoros Gialamas Avgoustinos Avgoustis

This research is a study on the relationship of irrigation water treatments and soil moisture distribution uniformity (DU). Soil moisture distribution was based on long-term data sets that were collected during wet and dry soil conditions (from permanent wilting point to field capacity) using a novel electromagnetic sensor-based platform moving inside subsurface horizontal access-tubes. The irr...

Journal: :تحقیقات مهندسی کشاورزی 0
علی اصغر قائمی استادیار بخش آبیاری دانشکده کشاورزی دانشگاه شیراز

center pivot irrigation system is used as a modern irrigation method in different parts of iran. unfortunately due to lack of proper design and hydraulic shortcomings of the system in several agricultural lands in iran, the efficiency of the center pivot irrigation system is low or unacceptable. low system efficiency results in non-uniformity of water distribution along the lateral and on the c...

2007
Rodrick D. Lentz

Rodrick D. Lentz* USDA-ARS Northwest Irrigation and Soils Research Lab. 3793 N 3600 E Kimberly, ID 83341 High water infiltration rates in unlined canals, reservoirs, and the inflow end of furrows relative to outflow ends result in excessive seepage losses and reduced furrow irrigation application uniformity. This study evaluated the use of cross-linked, anionic, polyacrylamide hydrogel (XPAM), ...

ژورنال: علوم آب و خاک 2017

Considering water scarcity in Iran, application of deficit irrigation or water stress on some crops is inevitable. We need to provide appropriate design for deficit irrigation. Furrow irrigation management to obtain high efficiency and uniformity is difficult. Therefore, to investigate the variation of the input discharge, the cut-off time and furrow length that are effective on the efficiency ...

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: :تحقیقات آب و خاک ایران 0
سعید زمانی دانشجوی کارشناسی ارشد دانشکدة کشاورزی دانشگاه ارومیه جواد بهمنش دانشیار دانشکدة کشاورزی دانشگاه ارومیه کامران زینال زاده استادیار دانشکدة کشاورزی دانشگاه ارومیه

increasing water distribution uniformity in micro irrigation systems has been an important subject in applied researches. despite considerable progress in emitters’ construction, some research reports refer to their incapability in water distribution uniformity. in order to achieve greater uniformity in micro irrigation, it is necessary to manufacture emitters with low variation in manufacturin...

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