Showing 5 results for Application Efficiency
Sayed Farhad Mousavi, Behrouz Mostafazadeh, Shokrollah Absalan,
Volume 2, Issue 4 (1-1999)
Abstract
This study aims to evaluate the present management of border irrigation systems applied to wheat, alfalfa and sugar-beet farms in Boyer-Ahmad and Gachsaran cities in Kohgiloyeh and Boyer-Ahmad Province. Experimental farms included 8 alfalfa farms, 5 wheat farms and 5 sugar-beet farms. The experiments were conducted at different growth stages of plants and customary borders with prevalent dimensions, slopes, and management practices. The relationship between management allowable deficit, moisture deficit before irrigation, and infiltrated depth indicated that in most cases either “deficit irrigation” or “stress irrigation” had been applied. This type of irrigation has positive effects on water use but negative effects on supply of required soil moisture for plants. In the first to third irrigations, measured application efficiencies ranged from 40.8% to 100%, 52.2% to 100%, and 61.1% to 100%, respectively. Graphs of advance, recession, and ideal recession showed the effects of border slope and length on inflow cut time and uniformity of water distribution. Water infiltration curves showed the amount of deficit irrigation. The results showed that weak irrigation management is the result of three parameters: lack of knowledge on the part of farmers about soil moisture conditions and correct time for irrigation, weak irrigation scheduling, as well as an imbalance between available water supply and irrigation requirements which leads to wasting water and reduced irrigation efficiency.
T. Sohrabi, U.a. Khoshkhahesh,
Volume 3, Issue 4 (1-2000)
Abstract
The purpose of this research is to determine the application efficiency of rice irrigation plots and to analyze the reasons for low efficiency. The study will also try to determine the effective factors which could increase the application efficiency of rice fields. The selection of rice fields was based on climate, soil characteristics, and farmer management. Water application efficiency was determined by field measurements in three modern irrigation networks named Fouman (F), Rasht (G) and Lahidjan (D). In the meantime, a traditional network was included for comparison. In the study areas, the soil texture was heavy with an infiltration rate of less than 3 mm/day. The study was carried out under two different conditions: (1) without return flow and (2) with return flow. In the first case, the average application efficiencies in Fouman (F), Rasht (G) and Lahidjan (D) were about 51.2, 49.0 and 49.4 percent, respectively and the maximum and minimum values were about ((52.6, 49.7)), ((50.7 , 47.3)), and ((50.7 , 48.0)) percent, respectively. In the second case, the average application efficiencies for the above-mentioned regions increased to 73.4, 73.3 and 72.4 percent, respectively and the maximum and minimum values were about ((74.3, 72.4)), ((74.3, 72.1)), and ((73.0, 71.5)) percent, respectively. Runoff ratios in the above-mentioned regions were 30, 33 and 31 percent, respectively. During growing period (from transplanting to harvesting), the average applied irrigation water was about 1130 mm (11300 m3/ha) and the average evapotranspiration was determined to he about 561mm.
S. Akhavan, S. F. Mousavi, B. Mostafazadeh-Fard, A. Ghadami Firoz Abadi,
Volume 11, Issue 41 (10-2007)
Abstract
To investigate yield and water use efficiency (WUE) of potato with tape and furrow irrigations, an experiment was performed at Hamadan Agricultural and Natural Resources Research Center (Ekbatan station) in 2004. The experiment was arranged in a split-plot experimental design based on completely randomized block with 3 replications of irrigation water amount as the main factor (75%, 100%, 125% of cumulative evaporation from class A pan) and sub-factor of irrigation method [including tapes in the middle of furrow ridge on soil surface (TD0), tapes in the middle of furrow ridge at the depth of 5 cm (TD5), tapes on the sides of furrow ridge on soil surface (TS0), and furrow irrigation (F)]. The results indicated that yield of potato increased with increasing water use. Regardless of irrigation method, maximum (32.51 ton/ha) and minimum (19.33 ton/ha) yield of potatoes was achieved with 125% and 75% irrigation water treatments, respectively. The lowest yield (21.35 ton/ha) was obtained in furrow irrigation and the highest yield (28.91 ton/ha) belonged to tape irrigation (TD5 treatment). The highest WUE (4.68 kg/m3) belonged to tape irrigation (TD5 treatment) and the lowest WUE (3.32 kg/m3) belonged to furrow irrigation (F). The difference in WUE between 75% and 100% irrigation water treatments was not significant. The highest WUE (4.49 kg/m3) was achieved in treatment 125%. Also, it is more economical to use irrigation water treatment of 125%, as compared with other irrigation water treatments.
A. Faryabi , E. Maroufpoor , H.ghamarnia ,
Volume 14, Issue 54 (1-2011)
Abstract
Precision in design of sprinkler irrigation systems and their proper management are very important for both development and also improvement of those systems. Therefore, the main objective of this study was to evaluate the design and management of the solid-set sprinkler systems in Dehgolan plain located in Kurdistan province. For this purpose, 10 solid-set sprinkler systems were selected randomly and a few performance parameters such as: Christiansen’s uniformity coefficient (CU), distribution uniformity (DU), potential application efficiency of low-quarter (PELQ) and application efficiency of low-quarter (AELQ) were estimated. The results of investigation showed the mean values of 66, 50.6, 44.8 and 43. 8%, for the above mentioned parameters, respectively. Also, the results of investigation showed both low PELQ values and water distribution uniformity of those evaluated systems compared to the recommended values by Merriam and Keller (1978). Moreover, due to deficit irrigation, except for one evaluated system, in all other systems, AELQ values were equal to PELQ. The results of our investigation also showed that non-suitable design and implementation of the evaluated systems were among the most important reasons for low values of PELQ, because of non-suitable operating pressure. The most important reasons for low water distribution uniformity were the simultaneous use of many sprinklers and also performance of different sprinklers models in a system. Finally, the results of our investigation showed poor operation for the evaluated systems in many cases.
F. Haghnazari, M. Ghanbarian Alavijeh, A. Sheini Dashtegol, S. Boroomand Nnasab,
Volume 25, Issue 1 (5-2021)
Abstract
Changes in soil infiltration cause changes in irrigation efficiencies; therefore, estimating it in calculating irrigation efficiencies provides a more accurate estimate of irrigation performance indicators. In a study conducted on ARC2-7 farm in Amirkabir agro-industry in the 2010-2011 crop year, during four irrigations; two furrows were selected in terms of uniform infiltration and variable infiltration with a length of 140 and a width of 1.83 m. In the furrow assuming uniform infiltration two flume type II, at the beginning and end of it, were installed and the cumulative infiltration was determined by the volume balance method. The furrow with variable conditions was divided into four sections by installing five flumes. By examining the spatial variations of the mean cumulative infiltration, its value decreased from the first to the fourth section for the first irrigation by 15% and for the subsequent irrigations by 13%. Temporal changes of cumulative infiltration decreased by 27 and 30% for the first and second sections and by 26% for the third and fourth sections. An 11% increase in the average weight of the aggregate diameter and a 7% decrease in bulk density indicate physical changes in the soil. Surface runoff losses increased from 8 to 18.77% in the furrow assuming uniform infiltration and from 10.91 to 19.77% in the furrow with variable infiltration, and application efficiency decreased by 6%.