Kh. Barati; B. Mostafazadeh-Fard; A. A. Sheikhbahaei
Abstract
The main problem with trickle irrigation is the emitter’s clogging. Using Merus ring is a new method for reducing sedimentation. The effect of Merus ring is based on molecular oscillations of salts in water and the performance of this device is not based on magnetic field. This study was performed ...
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The main problem with trickle irrigation is the emitter’s clogging. Using Merus ring is a new method for reducing sedimentation. The effect of Merus ring is based on molecular oscillations of salts in water and the performance of this device is not based on magnetic field. This study was performed in a field located at Isfahan University of Technology to investigate the effect of Merus ring on emitter’s clogging. Two main treatments of irrigation water, one with Merus ring and another without Merus ring, and three sub-treatments of irrigation water salts were used. The experiment was run for three months and each treatment was irrigated for three hours every day. The results showed that the irrigation water treatment (irrigation with Merus ring and without Merus ring) had significant effect on average emitter’s discharge (qav) at 1% level and on distribution uniformity of emitters (EU) at 5% level. The average emitter’s discharge and distribution uniformity of emitters were higher for the treatment of with Merus ring as compared to the treatment of without Merus ring. For both irrigation water treatments, qav and EU decreased with time during the experiment, but the decrease was higher for the treatment of without using Merus ring. The results showed that the use of Merus ring causes lower emitter clogging and better irrigation performance
F. Soroush; B. Mostafazadeh fard
Abstract
Abstract
Furrow irrigation is one of the oldest methods of irrigation in which soil surface is used to convey and infiltrate water. The furrow geometry data are used for design, evaluation and simulation of furrow irrigation. With furrow geometry data, the furrow infiltration, irrigation efficiency ...
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Abstract
Furrow irrigation is one of the oldest methods of irrigation in which soil surface is used to convey and infiltrate water. The furrow geometry data are used for design, evaluation and simulation of furrow irrigation. With furrow geometry data, the furrow infiltration, irrigation efficiency and furrow erosion and sedimentation can be estimated more precisely. Furrow geometry is expressed with some power functions and the coefficients of these functions are used as input for surface irrigation models. In this article, a computer program with Matlab version 7 was written to calculate the furrow cross section functions. The functions are power functions and second order polynomial. To evaluate the model, two cross section data of a furrow irrigation field were used. The model predictions were compared with the two-point method of Elliott and Walker and the results showed that the coefficients of furrow cross section equations obtained by the Elliott and Walker are different with the model output. The results showed that the model is capable to predict the field cross-sectional data with high accuracy. The comparison of coefficient of determinations of the fitted power function and second order polynomial function to the field data showed that both functions can predict the field data closely.
Key words: Furrow cross section, Simulation, Geometry functions, Surface irrigation
F. Soroush; S.F. Mousavi; Kh. Razmjou; B. Mostafazadehfard
Abstract
Abstract
There is a gradual decline in the availability of fresh water to be used for irrigation in Iran. As a consequence, the use of treated wastewater and other unconventional sources of water for landscape irrigation are on the rise in arid and semi arid areas. Irrigation with wastewater changes ...
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Abstract
There is a gradual decline in the availability of fresh water to be used for irrigation in Iran. As a consequence, the use of treated wastewater and other unconventional sources of water for landscape irrigation are on the rise in arid and semi arid areas. Irrigation with wastewater changes the soil properties. Hence, a case study was performed to assess the effects of treated wastewater irrigation on nutrient and heavy metal absorption of a turf cover (DALZJ1 variety). In this research, the advanced treated wastewater (TW) of Shahinshahr Wastewater Treatment Plant was used and the effects of different percentages of water and TW (100% water, 50% water and 50% TW, and 100% TW) on three soil textures (sandy loam, loam and clay loam) for a period of 10 months was studied. Statistical design was based on a completely randomized design with factorial arrangement, with three replications. The results indicated that using TW for irrigating turf grass increased plant uptake of N and Cd. The maximum amount of K, Ni, Co and Pb was absorbed by turf grass from soils irrigated with 50% TW. Also, the absorption of P, Fe and Zn was not affected by TW in the irrigation water. Analysis of variance showed that there was no significant difference between soil textures on plant uptake of N, P, K, Cd, Co, Ni, Fe and Zn. The comparison of means showed that there was significant difference in grass Pb content among soil textures. The interaction effects of soil texture and percent TW showed that variation of uptake with increasing TW percentage in irrigation water was not linear and soil texture had no effect on the uptake of elements by this Zoysia variety.
Key words: Wastewater, Plant uptake, soil texture, Turf grass, Zoysia grass
S. Yousofi Moghadam; S.F. Mousavi; B. Mostafazadeh fard; M.R. Yazdani; A. Hemmat
Abstract
Abstract
Puddling is the most common method of land preparation of paddy fields in lowland rice cultivation. Puddling affects the physical, chemical and biological properties of soil and these changes are effective on rice growth. The soil that is more susceptible to changes in structure is easier ...
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Abstract
Puddling is the most common method of land preparation of paddy fields in lowland rice cultivation. Puddling affects the physical, chemical and biological properties of soil and these changes are effective on rice growth. The soil that is more susceptible to changes in structure is easier to puddle. This research was aimed to investigate the effects of different puddling levels on moisture content and bulk density of three dominant soil textures of paddy fields in Guilan province. The experiment was designed as factorial with completely randomized blocks having three replications. Undisturbed soil samples were taken from 3 different soils (silty clay, clay loam and loam) with cylindrical samplers with diameter and height of 50 cm. The soil samples were puddled by a laboratory apparatus. The puddling treatments were: P0 (no puddling), P1 (low puddling), P2 (medium puddling) and P3 (high puddling). Soil moisture content and bulk density of all soil samples was measured every 24 hrs for six days. Analysis of variance showed that puddling had significant effect (p < 0.05) on soil moisture content and bulk density. The water content of the puddled layers decreased with an increase in settling time. During drying period, P0 dried faster than P1, P2 and P3. In P0 to P3 treatments of the loamy soil, the moisture content decreased about 22.6, 16.3, 14.8 and 9.6% after 144 hrs past puddling, respectively. The trend was similar for other two soils. Measurement of bulk density in 0-15 cm depth showed that P1 caused bulk density of silty clay and clay loam soils to decrease 23.8 and 22.8%, respectively; however, it caused the bulk density of loamy soil to increase 4.1%. Bulk density increased with time in all the three soils. Bulk density increased with depth and this increase was higher for lower puddling levels. It seems that higher puddling levels are more suitable for paddy fields preparation because they loose water more slowly. To determine what puddling level is appropriate for different soil textures, parameters such as water infiltration, water retention and amount of water used should be investigated.
Key words: Puddling, Paddy fields, Soil bulk density, Soil moisture content, land preparation, Rice
