Journal of New Approaches in Water Engineering and Environment

Abstract The present study was conducted to evaluate the quality and hydrochemistry of Oqan River water using ion ratios and saturation indices. For this purpose, the results of physicochemical parameters analysis over an eight-year period (2010-2017) were used for two hydrometric stations located on the river Oqan. To analyze and identify the hydrochemical processes, Stiff, Pipers, Gibbs diagrams, ion ratios, CAI1 and CAI2 relationships and Chadha diagrams were used. Also, saturation indices and composite diagrams of saturation indices were used to predict and probability of precipitation or dissolution of some minerals. Finally, factor analysis was used to determine the number of factors affecting water quality of studied stations. Stiff and Piper diagrams results of Oqan river showed that the type and facies of hydrochemical stations are Ca-HCO3 Galikesh and Oqan stations. Based on Gibbs diagram, the water-rock reaction is the controlling factor of the water chemistry of the studied stations. The results of ion ratios and Chadha diagram indicate that reverse ion exchange and weathering of dolomite and limestone processes are two effective factors to alter water quality in the study area. Hence, river water is over saturated with dolomite, calcite and aragonite minerals, whereas it is under saturated with evaporite minerals such as halite, gypsum and anhydrite. The results of factor analysis revealed that two factors of geological formations dissolution in watershed river such as limestone and dolomitic rocks and discharge of domestic and agricultural wastewaters into river have the most influence on the water quality in the studied stations.

Abstract Direct cultivation of dry rice is one of the methods of cultivating this product that has attracted the attention of researchers today. It is favored due to its ability to reduce the use of agricultural tools and machinery, decrease labor force and seed consumption, and significantly lower the initial cost and input energy needed for planting. In order to investigate the water and energy efficiency of traditional and direct rice cultivation, a factorial experiment was conducted in the form of a randomized complete block in Mamsani city. The results showed that direct cultivation, compared to traditional cultivation, significantly reduced the yield of paddy. However, it did not have a significant effect on the physical and quality characteristics of the product. This study calculated the values of input and output energy, as well as the percentage share of each input. Additionally, it calculated the indicators of the ratio of input to output energy, economic energy efficiency, and physical energy efficiency for each treatment. The results of these indicators demonstrated that as input energy decreases, economic and physical energy efficiency increase. Among the treatments, the best treatment in terms of water and energy efficiency was the Shamim cultivar, followed by the Fajr cultivar. Therefore, direct cultivation of the Shamim and Fajr varieties is recommended for rice farmers in Mamsani city.

Abstract Nitrate anion is one of the most important indicators for determining the level of groundwater pollution around the world, ‎so that various researches have been done on it in different water resources in watersheds. In this study, the amount of ‎nitrate in 55 water sources was obtained in Sirjan plain‏. ‏Then, geostatistical methods such as ordinary krigin (OK), ‎inverse distance weight (IDW), normal distance weight (NDW), and co-kriging were used. To evaluate the performance of ‎prediction and estimation models, performance indicators of Coefficient of determination (R2), Root mean square error ‎‎(RMSE), Mean Square Error (MSE), mean absolute error (MAE), correlation coefficient (R) and coefficient Nash - Sutcliff ‎‎(NS) is used.‎‏ ‏After selecting the best method of interpolation, spatial zoning maps related to nitrate variable was prepared ‎in Arc GIS software. The results showed that the average nitrate of groundwater in Sirjan plain is lower than the ‎standard limit‏. ‏The Gaussin model was also considered the most appropriate. Also, ordinary Kriging method showed the ‎highest values in terms of coefficient of determination (R2) with 0.9604317, correlation coefficient (R) with 1 and Nash- ‎Sutcliff (NA) coefficient with 0.283255 and also showed the lowest values in terms of root mean square error (RMSE) with ‎‎2.54974, Mean Square Error (MSE) with 0.0000018181, mean absolute error (MAE) with 1.202976 in comparison with ‎other methods. The results also showed that the upward trend of nitrate content is from the surrounding and the margins ‎of the plains towards the center and northern parts of it‏.‏‎

Abstract Objective:The aim of the present research was to model the removal of lead and cadmium from the aqueous solution by nanocomposite prepared on the basis of mineral stabilizer,using artificial neural network model and ANN optimized with particle swarm optimization algorithms.
Methods:Adsorption studies were carried out in a batch manner by considering different parameters such as the initial pH of the solution,adsorbent dosage,contact time,initial concentration of the pollutants and temperature.These parameters were considered as the input of the models and the efficiency of pollutant removal was also considered as the output of the models.
Results:The results showed that the accuracy of the ANN-PSO model was higher than the ANN model, so that the value of the R2 statistic in the ANN model for removing lead and cadmium was 0.91 and 0.90, respectively,and in the ANN-PSO model, it was 0.96 and 0.95, respectively.Examining the convergence of the PSO optimization algorithm showed that in the first iterations where the population particles are randomly selected, the optimization error is very high in all cases. Over time, with the global search and convergence to the global optimal limits, the weighted inertia increases, and the slope of the changes of the objective function in the convergence graph decreases over time, until finally optimization takes place.
Conclusions:In general, the use of ANN-PSO model can provide fast and acceptable predictions about the effect of various factors on the removal process of pollutants and is a suitable and economical alternative in terms of cost and time for laboratory studies.

Abstract This study experimentally and numerically investigates the effectiveness of introducing slots into cylindrical bridge piers as a scour‑reduction countermeasure. Laboratory experiments were conducted under clear‑water conditions in a 15 m long rectangular flume. Four slot geometries—parallel, Y‑shaped, T‑shaped, and Sigma‑shaped—were examined to evaluate their influence on maximum scour depth and bed morphology. Three‑dimensional numerical simulations were performed using FLOW-3D. A mesh sensitivity analysis and turbulence model comparison were conducted to ensure numerical accuracy. Results showed that increasing mesh resolution significantly improved predictions, and the standard k-ε turbulence model with 1.7 million cells provided the best agreement with experimental data, with a relative error of about 8%. Comparative analysis revealed that slot geometry strongly influences flow structure and sediment transport. Among the tested configurations, the parallel slot achieved the greatest reduction in scour depth. The slot acts as a flow relief mechanism, allowing part of the incoming flow to pass through the pier body, thereby reducing stagnation pressure, weakening the horseshoe vortex system, and decreasing near‑bed shear stress. Overall, the results demonstrate that appropriately designed slots, particularly the parallel configuration, can effectively mitigate local scour and enhance the hydraulic performance and stability of bridge foundations

Abstract The combination of phytoremediation and porous concrete is a new technology used as a natural purification of porous concrete and resistant plants to remove or reduce the concentration of pollutants. In this study, the performance of porous concrete as a bed and plant on reduction of urban effluent pollution has been investigated. A channel with dimensions of 9 meters length, 30 cm wide and 20 cm height was constructed along with the wastewater treatment lagoon of Isfahan University of Technology. Then, blocks were made of porous concrete with dimensions of 30 × 30 × 15 cm, and placed in the channel. The vetiver grass with two different densities (12 and 27 plants) were placed between the porous concrete blocks. After 5, 7 and 9 hours, the wastewater samples were taken from the inlet and outlet basins. The reduction of BOD, COD, TSS and total coliform during the 5 hours retention time, were 16.1, 27.5, 20.6, and 19.1 percent, respectively. In the retention time of 7 hours, reduction were equal to 20.5, 33, 26.1 and 25.3 percent, respectively. The reduction of BOD, COD, TSS and total coliform during the 9 hours retention time, were 25.9, 38.5, 31.9 and 30.5 percent, respectively. In general, this research showed the performance of system was optimistic in reduction of BOD, COD, TSS and Total coliform

Abstract Today, the effects of climate change and global warming have been proven due to the increase in greenhouse gases in the world. In this research, the monthly values of temperature, precipitation and discharge of Jamishan Dam in the years 1988-2017 have been considered as the base period. Simulation of resources and uses of the jamishan Dam catchment area was investigated using the WEAP model with different cultivation patterns in the area. To evaluate the effect of climate change on precipitation and temperature parameters in this region, RCP8.5 scenario outputs of HADGEM2_ES and MIROC5 models and a series of CMIP5 reporting models were used and the output of these models was downscaled for the region. In this research, change factor method used for downscaling and the monthly temperature and precipitation parameters of Jamishan Dam were produced for the period 2021-2050. In order to study the runoff of the region due to climate change, the SVR model was studied. The results of the climate model show an average temperature increase of 0.5 to 1 ° C. The simulated rainfall results show that the average monthly rainfall under the RCP8.5 scenario in the future period in HADGEM2_ES model increased by 1.3% and in MIROC5 model decreased by 6% compared to the base period. Examination of the results of discharge forecast in SVR method indicates that runoff is associated with a decrease compared to the base period.Simulation of different cultivation patterns in WEAP shows that the average supply is 70% in the SVR method.

Abstract In recent years, unnecessary exploitation of water resources, especially groundwater resources, droughts, lack of protection in the use of water resources, population growth, etc. has led to water input as one of the most important. The most limiting factors of development should play a role in the agricultural sector. One of the ways that can some extent solve this problem is comprehensive water management, which is an important economic method and values can be balanced between supply and water demand. In this study, the production function method was used to determine the economic value of water in the production of wheat and barley products. EXCEL and SPSS software were used to analyze the data. The obtained results showed that the average amount of final production of irrigation water input for wheat and barley crop is equal to 0.240 and 0.268, respectively, with economic value of 3223.3 and 2813 Rials per cubic meter. Also, the highest water consumption in wheat and barley production was equal to 5200 cubic meters and 3100 cubic meters, respectively, and the average water consumption was equal to 4604.56 and 2793.7 cubic meters, respectively. Due to the fact that the final value of water production is more than the cost of irrigation water supply, if the price of agricultural water is not corrected, it will lead to improper harvesting and use of water resources. To prevent this, it is better to set the price of agricultural water based on the final value of production.

Abstract It is so vital to note the cultivation of rice because of its high irrigation water consumption. This crop is the most important food source in the Iran, hence, it is necessary to know how much irrigation water must be used to grow different rice cultivars under various cultivation types. On the other hand, applying farm tests to achieve the goal need high costs and waste much time. Regarding that, it is necessary to use crop modeling. In this study, AquaCrop was used to simulate yield, biomass and water use efficiency of rice. The research was conducted at Khuzistan Agricultrual Research Station. In this study, three types of cultivation (D1: transplanting, D2: current directs seeding consorted seeding, and D3: dry bed seeding) and rice cultivars (V1: Red-Anbori, V2: Champa, V3: Danial) were considered to simulate abovementioned parameters. MBE, RMSE and NRMSE values for seed yield were 0.25 ton.ha-1, 1.0 ton.ha-1 and 0.1, respectively. Those values for biomass were 0.3 ton.ha-1, 1.15 ton.ha-1 and 0.05, respectively, and for water use efficiency were 0.07 kg.m-3, 0.24 kg.m-3 and 0.03, respectively. EF values for seed yield, biomass and water use efficiency were 0.87, 0.56 and 0.65, respectively, and d values for all parameters were equal to 0.99. Regarding the results, AquaCrop had good accuracy for simulation of rice yield, biomass and water use efficiency.

Abstract The crop evapotranspiration (ET) has spatial and temporal variations within the region due to changes in meteorological parameters, phenological stage, and farm management conditions. The main objective of the present study was to compare the trend of temporal and spatial variations of grain maize evapotranspiration in Mahidasht using satellite images with available resources (due to lack of Lysimeteric data). In this study, the daily evapotranspiration for the four maize farms in the different parts of the plain was calculated using Landsat 8 satellite images and the SEBAL algorithm on six dates during the growing period of maize in the year 2014. Since there was no field measurement of ET to verify the results of estimated ET based on the SEBAL algorithm, the final results (evapotranspiration) and intermediate results (Land surface temperature, Albedo, and NDVI) calculated by the SEBAL algorithm were compared with acceptable values in the literature. Results showed a similar trend of estimated evapotranspiration by the SEBAL algorithm and AGWAT software. The trend of increasing and decreasing land surface temperature was rational. The average of NDVI during the growth period in the studied farms was between 0.47 and 0.53 which was acceptable. Albedo with an average of 0.17-0.18 had slight variations between the selected farms. Results showed rising in land surface temperature, evapotranspiration, and NDVI to the middle of the growth period and then reducing of these parameters. The average estimated maize evapotranspiration based on the SEBAL algorithm was between 3.35 to 8.53 mm/day for the six imagery dates.

Abstract The Center pivot system is one of the most advanced sprinkler irrigation systems that recently has been used in Iran. According to this research on the compatibility of the system with the cultural, economic, climate and optimization performance of the system is essential. The importance of this matter on one side and the lack of information on the other hand, it highlights the need for an investigation. In this regard, the evaluation of the Center pivot system in two speeds 10 and 60 percent took a radial and vertical. The uniformity coefficient (CU) in the radial arrangement of cans and in two speeds 10 and 60 % was 80.3 and 76.4%, respectively and the uniformity of water distribution (DU) was 72.6 and 65.5 respectively. Also the uniformity coefficient (CU) in the vertical arrangement of cans and in the same speed was 61.1 and 59.3 % respectively. Uniform distribution of moisture in the soil after irrigation with rate of 60% was 86.37 percent. So the amount of Uniform distribution of moisture in the soil was higher than the uniformity coefficient in the Surface Soil (CU). The main reason is the horizontal flow and water transfer in the soil and its influencing factors (Mass flow, Diffusion and Hydrodynamic dispersion). According to this and given the lack of available water resources in arid and semi-arid area, maybe there is no need to increase water of irrigation in order to increase the uniformity of water distribution to more than 70 percent

Abstract In rivers and especially in river bends, the variation of stream-wise flow velocity in width and depth directions is non-uniform and is affected by many factors including secondary flows, bed and bank roughness, and flow hydraulic characteristics. For calculation of two-dimensional flow velocity distributions in straight rivers many approaches have been presented by researchers, while in meandering rivers, due to the complex mechanism of flow pattern, the solution of velocity field is carried out by computational fluid dynamics software packages. In this research, the Chiu's probabilistic theory was used for solution of the flow velocity field in a river bend on the Gorganrood located in Goletsan province. Considering the lack of measured point velocity data in river bends, 6 field measurement series were collected in one of bends located about 200 m upstream of Aghghala hydrometric station. Among these measurements, 4 series are selected for the model calibration and 2 remaining series for the model validation. The results showed that the Chiu's method has an acceptable accuracy in simulation of flow velocity fields for river bend. The statistical measures for the obtained point velocities indicated that the mean errors of this method are 4.9 and 3.5% in the calibration and validation phases, respectively. The mean errors for the calculation of total flow discharges are 5.9 and 6.0% respectively.

Abstract Considering the plant's positive response to nitrogen, farmers consume nitrogen fertilizers as much as possible. Excessive consumption of nitrogen fertilizers imposes additional costs on farmers, environmental pollution and direct negative impact on human health. Therefore, it is important to determine the amount of nitrogen-nitrate in the soil, plant and irrigation water in order to use nitrogen fertilizers optimally. In addition, according to the nitrogen balance, the amount of nitrogen deficiency is calculated and given to the plant, therefore the overuse of fertilizer is avoided. Most of the usual methods for nitrate measurement are time-consuming and expensive, spectroscopic measurement (spectrophotometer) makes it possible to determine the amount of nitrogen-nitrate in each of the soil, water and plant in the shortest time, inexpensively and accurately. In this research, we introduced a quick method of measuring the amount of nitrate in each of the water, soil and plant. The results are presented in terms of practical units in the field and soil for farmers and students, including kilograms of nitrogen per ton of product and the amount of nitrogen given through irrigation or nitrogen available in the soil in kilograms per hectare.