Showing 35 results for Water Use
S. Heydari Soreshjani, M. Shayannejad, M. Naderi, B. Haghighati,
Volume 19, Issue 73 (11-2015)
Abstract
In order to investigate the effect of different levels of irrigation on qualitative and quantitative yield and determine the corn's optimum depth of Irrigation in sShahrekord, a randomized complete block design experiment was done with 7 treatments including 40, 55, 70, 85, 100, 115 and 130 percent of soil moisture deficit and three replications in furrow irrigation. Effects of irrigation levels on yield, water use efficiency, weight of dry matter, plant height, stem diameter, median diameter, length and weight of corn were significant. Different levels of irrigation had no significant effect on seed oil and protein content, but their impact on plant fiber content was significant. With increasing depth of irrigation, stem length, grain weight and plant fiber content increased. The minimum and maximum corn yield were related to 40 and 130% of full irrigation with the yield of 43.1 and 88.1 tons per hectare, respectively. The maximum and minimum use efficiencies were 55 and 130% of full irrigation treatments with values of 16.17 and 10.1 Kg per cubic meter, respectively. The result of economic analysis showed that the water consumption is 5/582 mm, equivalent to 86% full irrigation depth.
M. Shahsavari Gugharغ, A. Rezaei Estakhroieh, M. Irandost, A. Neshat,
Volume 22, Issue 1 (6-2018)
Abstract
With the increase of population, the optimal use of water resources is necessary. This study was carried out to evaluate the impact of different levels of irrigation on the yield, yield components and water productivity of corn using single and double row drip irrigation systems (Tubes type). . The experiment was conducted in a split plot design based on the randomized complete block design (RCBD) with three replications in 2012 in Hajiabad, Hormozgan Province. The treatments were comprised of three levels of irrigation as the main plot (100, 80 and 60% water requirement) and two patterns of irrigating water pipe installation (normal and every other row) as a sub-plot of the design. The results showed that irrigating with the 80 percent water requirement, in comparison with full irrigation, increased the total yield by 1.4%, the seed weight by 1.8%, the number of seeds per row by 8.7%, and the number of seed row per maize by 13%. In spite of yield superiority in the pattern of normally irrigating water pipe installation (10055.56 kg ha-1), against every other row installation (9366.67 kg ha-1), water productivity was more in every other row installation (1.089 kg m-3). Therefore, partial root-zone drying was recommended by the irrigation of the 80% plant water requirement for the maize in the region.
N. Nourmahnad,
Volume 22, Issue 2 (9-2018)
Abstract
Due to the water scarcity in Iran, it is important to provide strategies to reduce water consumption in the agriculture sector. Zycosil is a nanotechnology material that makes a great hydrophobe in the soil. This study was conducted based on completely randomized block design within microlysimeter with the height of 15 cm and the diameter of 8 cm to investigate the hydrophobic effect on the amount of consumed water in pepper. Sweet pepper seedlings were planted in them; then the treatments were applied. The Z25, Z50 and Z75 treatments consisted of covering 25, 50 and 75 % of the soil surface by Zycosil; these were compared with the control (Ctrl- no Zycosil application) in three replications. The results showed that Z75 treatment reduced 27% water consumption and increased the fresh yield by approximately 62 %. The increased yield of Z25 and Z50 was 5 and 26 %, respectively. Dry pepper yield was increased in Z25, Z50 and Z75 treatments by 22, 19 and 80%, respectively, as compared to Ctrl treatment. The amount of water consumed was decreased by 10 % per 25% coverage level. The least amount of water use efficiency was observed in the control treatment (1.28 gr/cm3). The Z75 had the highest water use efficiency (2.96 gr/cm3). Hence, the application of hydrophobic material such as Zycosil in the soil surface reduced water evaporation and increased water retention. This increased the yield and water use efficiency.
F. Sajadi, H. Sharifan, S. Jamali,
Volume 22, Issue 3 (11-2018)
Abstract
Yield is a function of root distribution and activity. In flood conditions, root growth and efficiency are essential for crop productivity. The goal of this study was to investigate the effect of different irrigation regimes on the root development, yield and yield components of green pepper (green Hashemi cultivars). This study, which was based on a completely randomized design with three replications under greenhouse conditions, was done at Gorgan University of Agricultural Sciences and Natural Resources in 2016. Different irrigation regimes consisted of 3 levels (100, 125 and 150 percent of water requirement). The results showed that the effect of different irrigation regimes on root volume, root length, root area and number of fruit was significant at 1 percent level (P<0.01), but water use efficiency, and fresh and dry weight of fruit were significant at 5 percent level (P<0.05). The results also revealed that green pepper plants were sensitive to over irrigation. Increasing irrigation levels from 100 to 125 percent of pan evaporation resulted in the reduction of root volume, root length, water use efficiency, number of fruits, and pepper fresh weight to 20, 13.8, 26, 29and 6.4 percent, respectively. As the conclusion, with the increase in water irrigation level, the fresh weight of the fruit was significantly decreased.
N. Salamati, H. Dehghanisanij, L. Behbahani,
Volume 23, Issue 1 (6-2019)
Abstract
In order to investigate the effect of water quantity in subsurface drip irrigation on water use efficiency of palm yield and yield components, and determining suitable irrigation treatments for three different date cultivars, a split plot experiment design in a randomized complete block design with three replications were applied for three cropping years (2013-2016), at Behbahan Agricultural Research Station. The applied irrigation water in three levels based on 75, 100 and 125 percent of water requirement in the main plots and three cultivars of Kabkab, Khasi and Zahidi dates were compared in sub plots. The irrigation level of 75% with 0.646 kg of dates per 1 cubic meter of water in terms of water use efficiency as compared to the other two levels of irrigation showed a significant superiority. The Khasi cultivar with 83.9 pips and 29.2929 fruits in the cluster ranked first. The irrigation level of 125% with 11.1% were higher in fruit moisture, and 100% and 75% irrigation levels with 9.6% and 7.8% moisture content were the next. The irrigation level of 125% for Kabkab cultivar with a volume of 11.1 cubic centimeters were ranked first. Optimizing water use and reducing it to 10606 cubic meters per hectare in irrigation level of 75% water treatment will save water consumption. If the basis for comparing the amount of water used in 100% water treatment is considered, then the use of subtropical drip irrigation reduces water consumption by 2509.6 and 5019.2 cubic meters per hectare, respectively, compared to 100 and 125% water requirements.
A. R. Alipour, S. H. Mosavi, A. Arjomandi,
Volume 23, Issue 2 (9-2019)
Abstract
Increasing the productivity and conservation of limited water resources in the agricultural sector, especially in the agricultural sub-sectors, is closely related to the revision of the traditional approaches of production system in the agricultural sector of developing countries. The aim of this study was to develop the optimal combination of crop production in Varamin Agricultural and Animal Husbandry Complex as one of the leading agricultural units in the agricultural sector of Varamin County with the emphasis on increasing water use efficiency. For this purpose, the statistical data and information of the 2015-2016 crop year of the complex were used in the framework of the multi-criteria decision making model. The results showed that in the optimum crop pattern in this unit, the priorities of maximizing net energy production and the annual profit as the economic goals would be significantly aggregated with the goal of increasing water use efficiency. Accordingly, in the optimum condition, net energy production was increased by 10%, gross profit was improved by 4%, and water use efficiency was promoted by 15%. Therefore, according to the results, it is suggested that, in order to achieve the economic aspirations and increase water use efficiency in Varamin Agricultural and Animal Husbandry Complex, wheat, alfalfa, silage and maize corn, based on the values calculated in this study, constitute the main combination of the crop production pattern.
M. Mokari, H. Dehghan, M. Taherian,
Volume 23, Issue 4 (2-2020)
Abstract
In order to investigate the effect of new deficit irrigation strategies on the quantitative characteristics and water productivity of two field grown corn cultivars, a split plot experiment was conducted as a randomized design in three replications. The irrigation treatments included full irrigation treatment (FI), static deficit irrigation (SDI), dynamic deficit irrigation (DDI), static partial root zone drying irrigation (SPRD), which received 75% of ET during the growth period, dynamic partial root zone drying irrigation (DPRD), which received 90% of ET in the first one- third of the growth period, 75% of ET in the second one- third of growth period, and 50% of ET in the last one- third of the growth period. The results showed that there were significant differences between irrigation strategies. The SDI, DDI, SPRD and DPRD irrigation treatments decreased the corn yield by 18%, 27%, 49% and 53%, as compared to FI, respectively. The results also showed that there were no significant differences between cultivars. Compared to FI, the SDI increased WP by 14%, but DDI, SPRD and DPRD decreased WP by 3%, 19% and 44%, respectively. According to economic analysis, irrigation optimum depth for the maximum net profit was obtained to be 858.5 mm. In general, the SDI strategy is recommended in the study area.
M. Amerian, S. E. Hashemi Garmdareh, A. Karami,
Volume 24, Issue 3 (11-2020)
Abstract
Today, one of the biggest challenges facing the world is the lack of water, especially in the agricultural sector. In this research, we investigated the effects of irrigation method and deficit irrigation with the urban refined effluent on biomass, grain yield, yield components and water use efficiency in single grain crosses 704 maize. This research was carried out in a randomized complete block design with two irrigation systems (furrow irrigation (F) and drip irrigation (T)) and three levels of deficit irrigation treatments of 100 (D1), 75 (D2) and 55 (D3) percent of water requirements in three replications, in 2017, at the collage of Abourihan Research field, University of Tehran, in Pakdasht County. The results showed that the highest yield of biomass was 2.426 Kg m-2 for full drip irrigation treatments; also, there was no significant difference between D1 and D2 treatments. The highest grain yield was 1.240 kg m-2 for the complete drip irrigation treatment. The highest biomass water use efficiency was obtained for the treatment of 75% drip irrigation, which was equal to 5.3 kg per cubic meter of water. Therefore, a drip irrigation system with 75% water requirement is optimal and could be recommended.
N. Salamati, A. Danaie,
Volume 24, Issue 4 (2-2021)
Abstract
In order to study and evaluate the drought stress indices in surface irrigation by furrow method on grain yield, the yield components and water use efficiency, an experiment was conducted at Behbahan Agricultural Research Station in 2014-16. The experiment was conducted as a split plot in a randomized complete block design with 4 replications. Irrigation at two levels (irrigation after 100 and 200 mm evaporation from Class A pan, respectively) was evaluated as the main factor and corn cultivar was considered at 6 levels as the sub-factor. Comparison of the mean water use efficiency in irrigation and cultivar interactions showed 100 mm evaporation from Class A pan and cultivars V4 (PH1), V5 (PH3) and V2 (SC Mobin) were ranked the first and foremost, respectively, with the yields of 1.353, 1.299 and 1.296 kg of corn per kg of water consumed, respectively. The mean water consumed in 2014 of the experiment in 100 and 200 mm evaporation from Class A pan was 521.2 and 462.4 mm, respectively. Pearson correlation coefficient results also showed that with increasing the yield components, such as the number of grains per row and number of rows, the 1000-grain weight was increased due to the highly significant correlation coefficient of 1000-grain weight with grain yield (r = 0.8776). Consequently, grain yield was also increased. The highest values of SSI, STI, MP, TOL, GMP HM and YI indices were calculated in V4 (PH1). The higher values of the above indices in cultivar V4 (PH1) than other cultivars caused this treatment to be introduced as the superior one. The decreasing trend of corn yield, which was caused by water deficit stress, increased SSI, STI, MP, TOL, GMP and YI indices, while it decreased corn yield, leading to incremental changes in the YSI indices.
N. Salamati, A. Danaie, L. Behbahani,
Volume 25, Issue 2 (9-2021)
Abstract
To investigate and evaluate the effects of different levels of drip irrigation on grain yield and yield components, oil yield, seed oil percentage, and seed water use efficiency, an experiment was performed at Behbahan Agricultural Research Station during two crop years 2018-19 and 2019-20. The experiment was conducted in split plots based on a randomized complete block design with 3 replications. The amount of water in tape drip irrigation was compared at four levels of 40, 60, 80, and 100% water requirement in main plots and two sesame cultivars Local of Behbahan and Shevin in subplots from the beginning of flowering. Comparison of mean interaction effects of irrigation levels and cultivars showed that the treatment of 100% water requirement in the Behbahan local cultivar with the yield of 1218.0 kg/ha was ranked first and foremost. Water consumption in the highest treatment (100% water requirement and Behbahan local cultivar) was calculated to be 5389.4 m3/ha. Treatments of 100% and 80% of water requirement in superior cultivar (local Behbahan) with water use efficiency of 0.226 and 0.210 kg/m3 had no significant difference, respectively, and were in the first place. Pearson correlation coefficient calculated for the measured traits showed that the highest correlation of water volume was calculated (r = 0.9271) with the weight of one thousand seeds. Significant correlations of water volume with grain yield and yield components indicated that sesame was susceptible to drought stress and attention to optimal water management in sesame cultivation. Therefore, decreasing the volume of water consumed and consequently drought stress in sesame reduced yield and yield components.
M.m. Matinzadeh, J. Abedi Koupai, M. Shayannejad, A. Sadeghi-Lari , H. Nozari,
Volume 25, Issue 4 (3-2022)
Abstract
Using water and fertilizer management at the farm level can be increased water use efficiency and reduce the volume of drainage water, fertilizer losses, and other pollutants in farmland with deep underground drains such as Khuzestan agro-industrial Companies. In the present study, a comprehensive simulation model for the water cycle and the nitrogen dynamics modeling was used for water and fertilizer management modeling on farmland of sugarcane in Imam Agro-Industrial Company using a system dynamics approach. To reduce irrigation water consumption and nitrogen fertilizer losses, five different scenarios were considered including four scenarios of water management consist of 5, 10, 15, and 20 percent reduction in the amount of irrigation water (I1, I2, I3, and I4) compared to the current situation of irrigation in Imam agro-industrial Company (I0), and one scenario of integrated water and fertilizer management (20% reduction in the amount of irrigation water and urea fertilizer 210 Kg/ha, I4F). The results of modeling showed that the scenario of I4F caused to reduce 31, 70, 71, 70, and 85 percent of the cumulative volume of drainage water, cumulative nitrate and ammonium losses, total losses of cumulative nitrate, and ammonium by tile-drain and cumulative losses of denitrification process, respectively. Thus, the implementation of this scenario, not only saves water and fertilizer consumption but also reduces environmental pollution effectively. So the scenario of I4F (amount of irrigation water for six months 2656 mm and urea fertilizer 210 Kg/ha) is recommended for sugarcane in the Imam agro-industrial Company.
M. Abdi, H. Sharifan, H. Jafari, Kh. Ghorbani,
Volume 26, Issue 2 (9-2022)
Abstract
The irrigation schedule of crops is the most effective way to increase agricultural water use efficiency. In irrigation planning, determining the irrigation time is more important and difficult than determining the depth of irrigation water. Among all methods of determining the irrigation time of crops, the methods which used plants are more accurate than other methods. In this study, the wheat water stress index has been used which is based on the air vapor pressure deficit and the difference between vegetation and air temperature (Tc-Ta). First of all, the diagram and the relationship between the top and bottom baselines were extracted, then the water stress index of wheat was drawn in the Karaj region. Secondly, to determine the optimal water stress index of wheat, four treatments including I1: 30% of maximum allowable depletion of moisture, I2: 45% of maximum allowable depletion of moisture, I3: 60% of maximum allowable depletion of moisture, I4: 75% of maximum allowable depletion of moisture were performed in four replications. The amount of water stress index of each treatment was calculated during the season separately, and the CWSI of the treatment with the highest water use efficiency was used to determine the irrigation time of wheat. The results showed that the relationship between the upper and lower baseline for wheat in the Karaj region is Tc-Ta = 3.6 0c and
Tc-Ta = -0.27VPD - 2.64, respectively. The treatment of 45% of maximum allowable depletion of moisture had the highest water use efficiency and the optimal water stress index for wheat was obtained at 0.36 in the Karaj region.
A. Yousefi, M. Maleki-Zadeh, A.r. Nikooie, M.s. Ebrahimi,
Volume 26, Issue 4 (3-2023)
Abstract
This study determines the amount of irrigation water saved as a result of the subsidy policy to adapt from flood to drip irrigation. We developed a positive mathematical programming model (PMP) to evaluate the effect of economic incentives on farmers’ decisions to choose the type of irrigation technology, cropping pattern, and "water use" and "water consumption" in rural Garkan Shomali district, which is part of the Najafabad aquifer. We collected data through farm surveys, desk research, and expert interviews. The results showed that a reduction in the financial costs of converting flood irrigation into drip irrigation can lead to farmers investing in this technology. In the current water allocation scenario, the subsidy policy increases the water consumption of drip-irrigated crops by 28%, of which 19% is non-consumed water before subsidy payment and the rest is related to the reduction of furrow-irrigated lands. Also, under non-volumetric water delivery conditions, the operating costs reduce and the net income of the farms increases because of the increase in efficiency and the development of the area under cultivation, which increases water consumption while the water use is constant. In the volumetric water delivery scenario, with the increase in subsidies, the net income of the farms will increase without developing the area under cultivation and only because of the increased yield. Therefore, subsidy policy increases irrigation efficiency at both the farm and regional levels and is an effective tool for dealing with drought conditions.
M. Farzamnia, M. Miran Zadeh,
Volume 26, Issue 4 (3-2023)
Abstract
The present study was carried out in the Mahyar region of Esfahan Province to determine optimum drip tape spacing for the wheat crops on a silty clay loam soil respecting grain yield as well as yield components, water use efficiency, and variations in the salinity within the soil profile. The experiment was performed for three years from 2017 to 2019 with a randomized complete block design with three replicates and four treatments. The treatments consisted of three tape spacings (A) at 45, (B) at 60, (C) at 75 cm, and the Control (D) was irrigated with the basin method. The same volume of irrigated water was applied to the drip treatments, A, B, and C in every irrigation interval, whereas for treatment D, the local farmers’ practice was followed. Based on the results from compound variance analysis, the treatment effect on both grain yield and biological yield, and on water use efficiency and harvest index was significant at 1% and 5% level of confidence, respectively. The mean water use efficiency in treatments A, B, C, and D was measured as 0.79, 0.79, 0.73, and 0.78 kg m-3; thus, treatments A, B, and D outperformed treatment C. A comparison between the salinity of the soil profile at the beginning and the end of the growing season revealed that the basin irrigation method was more effective on salt leaching than the drip tape system. The results of this study indicated that concerning water use efficiency and crop yield, drip tapes spaced at 45 or 60 cm outperformed those which were 75 cm apart. On the other hand, the work required for irrigation system installation as well as the amount of drip tape residues left on the field at the end of the growing season is larger for tapes spaced at 45 cm compared to those which are 60 cm apart. This will have a significant impact on farmers’ budgets and environmental issues. Therefore, it is recommended to lay the tapes 60 cm apart for the irrigation of wheat crops on silty clay loam soils.
S. Aghaei, M. Gheysari, M. Shayannejad,
Volume 27, Issue 2 (9-2023)
Abstract
Due to water scarcity, it is impossible to utilize all irrigated cropland in arid and semi-arid areas. Therefore, dense cultivation with a drip irrigation system that delivers water directly to the plant's root zone is an appropriate choice to enhance water productivity. The objectives of the present study were to compare wheat yield and water productivity under two different water distribution patterns in the drip-tape irrigation system and surface irrigation in full irrigation and deficit irrigation levels. The experimental treatments consist of two irrigation systems (drip-tape (DT), and surface irrigation (SU)), and three different irrigation levels (a full irrigation level (W1), two deficit irrigation levels, the irrigation interval twice, and the same irrigation depth of W1 level (W2), applied half of the irrigation depth of W1 level at the same time (W3)). The SU was implemented in place with 100% efficiency to avoid runoff. The yield in full irrigation level in DT was 5338.4 kg/ha and in SU was 5772.8 kg/ha. Applying deficit irrigation in two irrigation systems has different effects due to various water distribution patterns. In the DT, the most yield reduction was in W2, and in SU was in W3. The highest water productivity in DT was observed in W3 with a 1.44 kg/m3 value. The highest water productivity in SU was observed in W2 with a 1.46 kg/m3 value. For each irrigation system, some type of deficit irrigation management is optimal.
