Background and Objectives: Surface IRRIGATION is the most common method of IRRIGATION. over 80% of agricultural lands in Iran are irrigated by this method. Generally, this technique has lower investment and energy requirements than pressurized IRRIGATION methods. Many efforts are applied to improve the economic output of water use and to preserve the environment in Iran. Modifying the design and MANAGEMENT parameters at the farm level can improve the performance of IRRIGATION systems. The main objective of this study is to optimize surface IRRIGATION efficiency, with low-cost tools, using a simulation model. Materials and Methods: The study areas were selected fields of the Molla-Sani region in Khuzestan province, located southwest of Iran. Field experiments were carried out in two fields, irrigated using a surface IRRIGATION system. Three IRRIGATION events and three plots (as repeats) were applied per field. Experiments were conducted on the three borders of 150 m in length, 7 m in width, and 0. 125 % slope, in Field 1, and on three borders of 200 m in length, 7 m in width, and 0. 1 % slope, in Field 2. The inflow rates of 25 and 35 L/s were applied in fields 1 and 2. The Inflow rate was checked using a W. S. C flume. The borders were divided into parts of 10 m distances to measure the advance and recession times. The best combination of parameters was determined with the simulation model. The objective function (OF) including the application efficiency and the distribution uniformity was applied to optimize the IRRIGATION performance. Results: This study showed that, based on the simulation model, changing the inflow rate, does not affect the best value of an objective function. The optimal inflow rate and cut-off time are recommended as 35 L/s and 30 min in a border with a length of 50 m, in Field 1, and, the best performance in Field 2, is obtained from the inflow rate of 20 L/s and the cut-off time of 48 min and length of 50 m. Field experiments showed that the difference in infiltration rates, was not significant, during this study. Based on the data obtained from three events, in both fields, and analyzed via the simulation model, the average NRMSE (Normalized Root Mean Square Error) index values for the evaluation of the advance curves were 12. 7, 12. 5, and 11. 6%, while the recession curves were 6. 9, 6. 8, and 6. 6%. Conclusion: Pressurized IRRIGATION has the high investment and energy requirements than surface IRRIGATION. Furthermore, the evaporation rate is much, in the research region. Because the inflow rate and cutoff time are the most effective parameters in improving IRRIGATION, thus, in this region, prediction and selection of the optimum combination of cut-off time and inflow rate are the low-cost tools to improve the surface IRRIGATION performance compared to modifying length and slope in border IRRIGATION or transform of surface to the pressurized system, in the farm level.

Rice is most important agricultural crop of Guilan province sensibility to salinity and alkalinity of water and soil. In recent years, using of toxicants and fertilizers in farmlands, constructing several dams upstream, entering agricultural, homemade and industrial sewage in to a river, and drought have decreased gradually discharge of river and increased salinity of Sefidrud River as an IRRIGATION source of Sefidrud IRRIGATION network of Guilan province. This research tries to determine the optimal INTERMITTENT and depth of irrigating of rice in proportion to salinity of Sefidrud River using of OPTIMIZATION- simulation mechanisms as is the decrease in crop efficacy become minimum. To achieve this, an agro hydrological SWAP was used to simulate different stages of rice growing and an OPTIMIZATION model was used in a reasonable range of the INTERMITTENT rice IRRIGATION period and depth with regard to different growth stages. Because some types of rice are affected by salinity, field experiments of Hashemi variety in Rasht in 1386 were used to calibrate the model. Optimal values of the INTERMITTENT IRRIGATION regime in current salinity of the Sefidrud River (1.747 ds/m) included 8 days INTERMITTENT IRRIGATION period and the depth of water for irrigating was 1, 3, 4 and 5 for vegetative, tiller, maturity and harvest stages respectively. The comparison of results of OPTIMIZATION- simulation model with field data in 1389 showed good efficiency of this model in IRRIGATION OPTIMIZATION. In the field experiment 8 days INTERMITTENT period with IRRIGATION 5 cm in depth was highest crop performance in 2 ds/m salinity.

Improving water productivity is vital to sustain and raise crop production. In order to investigate the effect of water and nitrogen rates on wheat, a field experiment was conducted as split plot arranged in arandomized complete block design (RCBD) with three replications, during 2000-2002 at Maragheh. Rainfed Research Station, The treatments included four levels of deficit IRRIGATION (rainfed, %33 F.I., %66F . I, and Full IRRIGATION (F.I)) and five nitrogen rates (N0, N30, N60,N90, and N120kg.ha-1).Yields of rainfed conditions varied with seasonal rainfall and its distribution, with all main factors having significant effects on it. With IRRIGATION, yield response to N application was generally significant up to 90kgNha-1. Optimum level of deficit IRRIGATION was realized with %66 of full IRRIGATION treatment (%27.3 decreases in full IRRIGATION) which led to maximum IRRIGATION water productivity and with 4467kg.ha-1 grain yield. Water productivity based on IRRIGATION water alone (WPI) and both IRRIGATION - plus rainfall (WPI+p) at 90 kg.N.ha-1 over the two seasons were 9.58 and 27.92kg mm-1, respectively.

Water resources shortage threatens the sustainability of continuous flooding rice culture. To investigate the effect of initial flooding duration on herbicide efficacy and rice yield loss, a field experiment was conducted at Rice Research Institute of Iran, Rasht, Iran, in 2015. The experiment was arranged in a factorial arrangement based on randomized complete block design with three replications. The experimental factors were two rice cultivars (Hashemi and Gilaneh) and five initial flooding durations (flooding for 2, 4, 6, 8 and 12 weeks after transplanting and then applying INTERMITTENT IRRIGATION). Consistent with the paddy fields IRRIGATION method in northern Iran, 12-week flooding duration was considered as continuous flooding IRRIGATION. Results showed that there was no significant difference in herbicide efficacy between Hashemi (87. 9%) and Gilaneh (85. 6%) cultivars. No significant reduction in herbicide efficacy was observed when initial flooding duration reduced from 12 to 6 weeks, but with further reduction in initial flooding duration to four and two weeks, herbicide efficacy was significantly reduced. The highest paddy yield (3989. 2 kg. ha-1) was observed in permanent flooding (flooding for 12 weeks) + herbicide application treatment and the paddy yield was decreased about 10% by reducing the initial flooding duration to six weeks but it was not statistically significant. With further decrease in initial flooding duration to four and two weeks, rice paddy yield reduced significantly by 16% and 31%, respectively. In conclusion, results of this experiment revealed that under water shortage conditions, it is necessary to apply initial flooding duration at least for 6 weeks after transplanting for obtaining favorable herbicide efficacy (more than 90%) without paddy yield loss compared to permanent flooding treatment.

Water for rice cultivation is one of the main inputs. The new administration of irrigated rice is increase water efficiency and water conservation in the paddy fields. In this research, for OPTIMIZATION of INTERMITTENT IRRIGATION MANAGEMENT in proportion to water requirement of different stages of rice growth was present an OPTIMIZATION-simulation model to maximize IRRIGATION water, transpiration and evapotranspiration productivity Indexes. IRRIGATION water depth in stages of tiller, vegetative, maturity, harvest and IRRIGATION intervals were selected as decided values in OPTIMIZATION model. Simulation of plant growth stages, using the hydrological model SWAP and genetic algorithm was used to solve the OPTIMIZATION model to maximize agricultural productivity. Finally, the optimum amount of IRRIGATION water productivity, transpiration and evaporation - transpiration were obtained 1.60, 2.90 and 1.33 (kg/m3) respectively. Results showed, IRRIGATION water productivity index has more harmonize with Sefidroud IRRIGATION network. Also the index is user-friendly in applying and calculating. So according to maximizing of water productivity index IRRIGATION depth was recommended 51, 29, 39 and 11 mm respectively in stages of tiller, vegetative, maturity, harvest and and 8 days period of IRRIGATION intervals to improve water productivity index in Hashemi variety in Rasht. OPTIMIZATION results showed optimal INTERMITTENT IRRIGATION is successive compared with flood IRRIGATION in rice.

Improving water productivity is vital to sustain and improve crop production in Iran. A split plot trail (RCBD) was conducted in Maragheh agricultural research institute (DARI) over three seasons in 1999-2002 to examine the effect of applying different levels of supplemental IRRIGATION and nitrogen rates on grain yield of Sabalan rain fed wheat variety. The treatments included four levels of supplemental IRRIGATION (rain fed, 1/3, 2/3 and Full Supplemental IRRIGATION) and five N rates (0, 30, 60, 90 and 120 kg. N. ha .I). Yields of rain fed conditions varied with seasonal rainfall and its distribution, with two factors having significant effects. With IRRIGATION, crop response was generally significant up to 60 kg. N. ha-l, while optimum response for rain fed conditions was until 30 kg.N.ha-1. Optimum level of supplemental IRRIGATION was with 1/3 of full supplemental IRRIGATION was obtained maximum water productivity (WPI) and good yields. The WPI+P and WPI for this treatments (IBF.ST, N60) averaged over the three seasons were 7.4 and 30 kg. mm-I.

In most of the countries in the world, even in the developed countries, surface IRRIGATION is still one of the important IRRIGATION methods in irrigated agriculture. It is estimated that more than 90 percent of the irrigated lands are irrigated with surface IRRIGATION methods. Since determination of optimum field’s dimensions, including slope, inflow rate, and IRRIGATION time, play an important role in enhancement of application efficiency and reduction of projects costs. Therefore, this research was conducted in the Ramshir IRRIGATION and drainage network in the Khuzestan province (namely Velayate plan) with the objectives of determining fields’ dimensions, design and MANAGEMENT parameters of border IRRIGATION with closed-end regime and for achieving higher application efficiency and distribution uniformity. Using water advance and recession measurements along the border length and use of a comprehensive surface IRRIGATION model, that is to say, WinSRFR-3.1 model, the soil infiltration parameters of the area were determined.Hence, the model was calibrated and the parameters of the best fitted infiltration equation, based on the Kostiakov-Lewis equation, was determined. Also by using the simulation part of the model, the dimensions and other design and MANAGEMENT parameters of border IRRIGATION, with closed-end regime cultivated with wheat crop, was determined. Based on results and with regards to proper application efficiency and distribution uniformity, the border design alternative of 7 m wide, 200 m length, and slopes of 0.005 to 0.001 m/m was a proper alternative for all ranges of selected inflow discharges (10-20 lit/s) and net IRRIGATION depths of 50 to 90 mm. However, based on results, the design alternative of 200 m border length and longitudinal slope of 0.0005 m/m is the best alternative with regards to higher application efficiency. Moreover, the longitudinal slope of 0.0005 m/m is an ideal slope for all combinations of design alternatives with fair application efficiencies. Basically, the border length of 300 m and higher are not a suitable option for all selected slopes and low inflow rates of less than 10 lit/s. Finally, in the Ramshir IRRIGATION and drainage network, if the field’s dimensions together with the other design and MANAGEMENT parameters is set properly, achieving high application efficiency, even higher than 70 percent, in the border IRRIGATION for many design alternatives is easily possible.

In the current study, economic analysis of deficit IRRIGATION was conducted for a Thomson orange orchard in Sari in two scenarios of considering applied water including 1-only IRRIGATION water, 2-IRRIGATION water plus rainfall. Production and cost functions were modified in water and land limitation conditions using English method. These functions were determined for without and 4 days IRRIGATION interval using mathematical analysis and aimed to obtain the maximum net income. Results showed that when rainfall occurs, IRRIGATION water plus rainfall should be considered as applied waer in production and cost functions. In addition, when there is no water limitation, the highest net income per unit of land is obtained from Wm that is 277. 4, 315. 6 mm for without and 4 days IRRIGATION interval. Production for this situation is 51. 3 and 57. 4 ton/ha, respectively. In water limiting condition, the optimum water depth (Ww) is 257. 6 and 287. 9 mm that causes more than 26% saved water. If there is also land limiting in this situation, the net income per unit of land decreases 3. 3 and 4. 1 percent. However, the net income per unit of water increases 4. 2 and 5. 1 percent. If there is no land limiting in this situation, by IRRIGATION equivalent to full IRRIGATION, the net income per unit of land increases 7. 5 and 9. 2 percent. This status obtains the highest net income per unit of water use. According to the current resutls, having an IRRIGATION schedule causes 12% increase in production and if it is associated with deficit IRRIGATION, causes 5% more increase in net income.

AbstractIntroduction: Effective MANAGEMENT in metropolitan planning of urban green space water resources is very important due to the rapid growth of urbanization and the limitation of water resources. The purpose of this research is multi-objective OPTIMIZATION and MANAGEMENT of treated wastewater allocation using dynamic system models for urban green space IRRIGATION in Shiraz metropolis.Methods: The factors affecting the supply of water resources and IRRIGATION of the green spaces of Shiraz city have been simulated and according to that, the consumption forecast and the number of available resources and the allocation OPTIMIZATION have been presented. Also, in the current research, effective factors in the current and future conditions that can affect the proposed model have been taken into consideration, and two scenarios have been applied, including increasing the efficiency of green space IRRIGATION and the use of treated wastewater.Results: The results showed that increasing the efficiency of IRRIGATION through MANAGEMENT of transfer, storage and distribution of water and also IRRIGATION at the right times has a much greater effect compared to the use of purified wastewater in order to reduce the extraction of limited resources. In such a way, by increasing the IRRIGATION efficiency by 40% and 50%, respectively, 14% and 39% of water shortages will be solved.Conclusion: The simulation results showed that in order to achieve the stability of the system, a combination of scenarios of reducing per capita water consumption in green spaces, increasing IRRIGATION efficiency, using purified wastewater and dry landscaped spaces should be considered in the development of urban spaces.