JWSS - Journal of Water and Soil Science

Nowadays, with the increasing population in Iran, especially in arid and semi-arid areas, as a result of the growing importance of the quality of water resources, including groundwater, field experiments and many simulations have been conducted for the development of groundwater contamination through powerful and up- to- date software. However, in most cases, there is a tangible difference between the measured data in laboratories and the data produced with software; this is why the scientific validation and verification of the research results could be declined. In this study, in order to justify and correct these data, the calibration principle was used to minimize the error of testing and modeling. The purpose of this study was to validate and verify the SUTRA model for different scenarios of the solute transport in a sand tank with heterogeneous hydraulic conductivity to evaluate transverse dispersivity. In this study, coding was initially performed for the configuration and calibration of the SUTRA numerical model to simulate different scenarios of the solute transport in a heterogeneous sand Tank in the Hydraulic Laboratory of the University of Kassel, Germany, until acceptable values were obtained. Then the results were compared with the experimental model. In order to validate and verify the data obtained from the simulation with the SUTRA model, the relevant concentration profiles were compared with the results of the experimental model. The results of the numerical and laboratory models revealed the density effects by sinking the geometric center of the mixing zone for the low concentrations of salt, C₀ = 250 ppm. The results also showed that the width of the mixing zone between salt and fresh water depended on the amount of longitudinal dispersivity, especially the transverse dispersivity. By analyzing the results of simulation and experiment, it was observed that with increasing the velocity, reducing the amount of sinking and raising the input concentration, the time needed to achieve the steady dispersion was decreased.

In this study, the groundwater level (GWL) of the Sarab Qanbar region located in the south of Kermanshah, Iran, was estimated using the Wavelet- Self- Adaptive Extreme Learning Machine (WA- SAELM) model. An artificial intelligence method called “Self- Adaptive Extreme Learning Machine” and the “Wavelet transform” method were implemented for developing the numerical model. First, by using the autocorrelation function (ACF), the partial autocorrelation function (PACF) and the effective lags in estimating GWL, eight distinctive SAELM and WA- SAELM models were developed. Later, the values of the observational well were normalized for estimating GWL. Next, the most optimized mother wavelet was chosen for the modeling. By evaluating the results of SAELM and WA- SAELM, it was concluded that the WA- SAELM models could estimate the values of the objective function with higher accuracy. Then, the superior model was introduced, showing that it could be very accurate in forecasting the GWL. In the test mode, for example, the values of R (correlation coefficient), Main absolute error (MAE) and the NSC- Sutcliffe efficiency coefficient (NSC) for the superior model were calculated to be 0.995, 0.988 and 0.990, respectively. Furthermore, an uncertainty analysis was conducted for the numerical models, proving that the superior model had an underestimated performance.

In this study, to evaluate the rain- fed land capability in the west of Gavkhooni basin and Plasjn sub- basin, a multi- criteria evaluation method was used. First, by reviewing the literature and expert knowledge, proper data were determined. Criteria and constraint were standardized by Fuzzy and Boolean methods repeatedly and the criteria weights were determined using the analytic hierarchy process. Calculated weights showed that soil and climate criteria with 0.27 and 0.26 had the highest weights among other criteria. Criteria and constraints were combined by considering criteria weights and using the weighted linear combination method; then the rain- fed land capability model was prepared. By re- classing the prepared model, the rain- fed land capability map was produced in 6 capability classes. The results showed that 178430 hectares of the study area was related to very high and high rain- fed capability classes. To determine the rain-fed agriculture sustainability, rain- fed agriculture locations were determined in each land rain- fed capability map. The results showed that 19686 hectares of rain- fed areas were located in high and very high capability and 5999 hectares were the in lower classes.

One of the ways to increase water productivity in agriculture is the use of new irrigation systems; for the precise design of these systems, water quality assessment is needed. The purpose of this study was to study the groundwater quality of Khorramabad plain for the implementation of drip irrigation systems. The qualitative indices of EC, SAR, TDS, TH, Na and pH were related to the statistical years 2006-2012. In this research, the data were normalized first and it was determined that the data were abnormal; so, the logarithmic method was used for normalization. To evaluate the groundwater quality of the area, land use methods were used. Among different methods, the ordinary kriging interpolation method with the least root mean square error for all parameters was used. Quality zoning maps showed that in the north and southwest, EC and SAR concentrations were in poor condition in terms of qualitative classification. TDS had a concentration of more than 4000 milligramrels, and Na had a concentration of more than 15 milligrams / ltr. In these areas, TH with the concentration of more than 730 mg / l had the highest contamination; in the central area of the plain, there was a higher risk of carbonate sediments. LSI rates in the western regions were more than one, which included about 12% of the plain; there were restrictions on the implementation of droplet systems in these areas. The best quality for implementing these systems was located in the south-east of the plain, covering 19% of the plain. Finally, the integrated map of qualitative characteristics showed that the maximum concentration of qualitative characteristics was located in the northern, central and southern regions, which included 62.29% of the plain area.

Constructed wetland as a purification system plays an important role in water and wastewater treatment and so many research studies have been conducted to examine their efficiency for wastewater treatment. The aim of this study was to evaluate the efficiency of constructed wetland for Arak wastewater treatment plant. In this research, the efficiency of three horizontal subsurface constructed wetlands built with 3*12 meters in dimensions and 1 meter in depth was examined. In these constructed wetlands, two plants including Common reed (Phragmites australis) and Cattails (Typha latifolia) were planted and one unit was left unplanted. TSS, COD, BOD and TC parameters were measured in the 2 week samples and the results were analyzed by SPSS and Excel. The results showed that the type of vegetation had no significant influence on the organic matter removal in the subsurface constructed wetlands; however, the removal efficiencies in the planted constructed wetlands were more than those in the unplanted control one. The TSS, COD, BOD, FC and TC removal efficiency in the constructed wetlands changes was 79%, 60.7%, 45.6%, 86.1% and 90.1%, respectively, for Common reed wetland and 77%, 61.4%, 59.8%, 92.4% and 93.1%, respectively, for Cattails wetland; thee were 69%, 44.5%, 43%, 83.6% and 88.8% for the  unplanted wetland, respectively. The results of this research also showed that the organic matter removal was dependent on the influent organics nature and biodegradability. The organic concentration in the wetland effluents met the Iranian regulation limits for different reuse applications, showing the constructed wetland could be a suitable technology for wastewater treatment in Iran.

Groundwater supplies a major portion of two basic human needs: drinking and agricultural water. Forecasting, monitoring, evaluating the performance and planning of this vital resource require modelling. The lag time of the groundwater level fluctuations against the rainfall is one of the essential data of the models. The purpose of the present study was to evaluate the piezometers behaviour by using the Pearson cross-correlation method between SPI and GRI indices in the Shiraz alluvial plain in order to determine the mentioned lag time. The results showed a similar behaviour for 86.2% of the piezometers. In 79.3% of the piezometers, groundwater level was declined one month after the rainfall event. The best correlation coefficient between the aforementioned indices was observed along the southwestern to the northeastern axis of the plain. The northern alluvial plain has a better correlation, as compared to the southern section because of the northern-southern slope of the plain. The central area of the plain had the highest correlation coefficient. The maximum correlation coefficients occurred at a time scale of 48 months. Also, since 2004, due to the decline in the atmospheric precipitation in the Shiraz plain, the SPI index has surpassed the drought level, although the trend has not been significant. However, the GRI does not follow this trend, showing a significant hydrological drought. The reason can be the disproportionate water extraction to recharge ratio in the alluvial aquifer of the plain.

One of the main sources of greenhouse gas (GHG) emissions is the use of energy for groundwater pumping. Reducing energy consumption is very important to achieve the environmental sustainability and decrease the climate change impacts. In this paper, the amount of greenhouse gas emissions from groundwater pumping in the Guilan’s aquifers was investigated. Firstly, groundwater depletion and the types of pumps for water pumping were examined in the current condition; then, the values of consumed energy, GHG emissions and climate change indicator of the current condition were estimated. The primary investigations showed that 55 percent of wells in the studied region had a diesel engine pump, while 51.3 percent of the required energy for groundwater pumping was supplied by electric pump. Calculated total GHG emissions and the value of climate change indicator in the current condition were equal to 8.98 and 7.59 Milion kg CO₂ eq , respectively. In order to achieve environmental sustainability and energy security, scenarios of replacing electric pumps and applying solar energy were examined. The results of the scenarios showed that diesel fuel wells had no significant effect on the reduction of greenhouse gas emissions, but the use of solar energy reduced them. GHG emissions, in comparison with the base scenarios, were decreased by 44.4% in June, July and August, respectively, by applying the scenario of using the solar pump in agricultural section. Therefore, it is preferred to apply policies in future planning to use renewable energies such as solar energy instead of diesel and electricity energy.

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.

This study was conducted to evaluate AquaCrop for the simulation of potato yield and water use efficiency (WUE) under different water stress values at five levels (E0, E1, E2, E3 and E4, indicating 100, 85, 70, 50 and 30 percent of crop water needed, respectively) in three times during growth cycles (T1, T2, and T3, indicating 50, 100, and 150 days after sowing, respectively). The results showed that AquaCrop had overestimated and underestimated error for the simulation of yield and WUE, respectively. Based on RMSE and NRMSE values, the errors for yield and WUE were acceptable. The maximum and minimum error were also 0.3 (E1T3) and 3.15 (E1T2), respectively. The results obtained for WUE showed that the maximum and minimum were 0.53 (E3T2) and 0.03 (E4T2), respectively. The average differences between simulated and observed results (ADSO) of WUE for E1, E2, E3 and E4 were 0.24, 0.25, 0.19, and 0.44 ton.ha^-1, respectively; the ADSO of yield for T1, T2, and T3 was 0.19, 0.36, and 0.22 ton.ha^-1, respectively. Therefore, AquaCrop showed a high error for WUE when water stress was increased and crop was in its initial crop growth.

Water scarcity is the most important factor constraining agricultural production all over the world and water shortage in agriculture must be established to use the deficit irrigation. In order to study the effects of the regulated deficit irrigation and partial root zone drying on the growth traits of Rosmarinus Officinalis L., an experiment was conducted in the center of seed and plant production of IranShahr municipality in 2017. The experiment treatments were arranged as a randomized complete block design with three replications. The irrigation regimes consisted of full irrigation, regulated deficit (RDI₇₅ and RDI₅₅) and partial root zone drying irrigation (PRD₇₅ and PRD₅₅). The results showed that deficit irrigation at 75 and 55 percent of full irrigation resulted in saving 18.6 and 34.3 percent of water consumption, respectively. Comparison of full irrigation and PRD₇₅ showed that dry weight, height of plants and number of shoots per plant were decreased by 6.7, 14.3 and 12.1 percent, respectively. However, proper development of root in PRD₇₅ increased 12.9 percent of water productivity. Therefore, by considering the problems of water scarcity, it is possible to provide PRD₇₅ as a superior treatment and a suitable strategy to cope with the water crisis in order to move towards a sustainable agricultural system.

Shortage of water resources and deterioration of water quality have urged the need to develop new technologies for the removal of contaminants from water. Heavy metals produced by municipal and industrial activities are among the most toxic contaminants present in the natural and waste waters. Different methods have been developed for the elimination of heavy metals from water resources and industrial waste waters. Adsorption is an effective and economic method for the water purification purposes. Nowadays, clays and natural polymers have been widely used as the adsorbents for heavy metals, due to their eco-friendly nature, natural abundance, low cost and high specific surface area. If these adsorbents are used as a hybrid material, some of their physical and chemical restrictions would be alleviated. In this study, polyacrylic acid–bentonite hybrids and natural bentonite were compared in terms of Pb adsorption in the batch and fixed-bed column systems. Besides, the effect of pH on Pb retention was investigated in both systems. The results of the batch studies showed that Langmuir and Freundlich isotherm models were appropriate in ing quilibrium Pb sorption data. Pb sorption by the sorbents was increased with the rise in solution of pH from 4 to 6, showing the greatest Pb sorption capacity at pH values of 4 (83.29 mg g^-1) and 6 (103.3 mg g^-1). Different indices of filtration and adsorption, including average relative effluent concentration, relative adsorption index, relative transmitted index, and filtration coefficient, were calculated from the break-through curves, indicating that the polyacrylic acid-bentonite nanocomposite was superior in the Pb sorbtion, as compared to bentonite. Also, a higher pH value resulted in the greater Pb removal from the solutions.  

This study focused on proposing a new operational perspective within main and lateral irrigation canals based on the economic value of water. To achieve this objective, the operation-economic framework offered in this study consisted of two main components of the PMP model and Operation model. The estimated economic values of water in different regions of the network were employed as the starting point for connecting the economic model with the operation model. It is worth mentioning that the technical perspective targeting adequacy of water distribution within the canals was modified in this study to be applied for the operation-economic framework since the original forms of the indicator were based on physical inherent of the water. Roodasht Irrigation District, located at Zayandeh-Rud basin, was selected as the case study, and the proposed framework was tested on the district. The obtained results revealed that in response to implementing the proposed framework in water distribution within the canal under the water shortage condition, alfalfa and safflower were the two crops those cultivation was decreased drastically in comparison with the other crops. The primary reason for the decrease was the lower values of the economic value of water for these two crops. Also ,the results of the canal operation appraisal from the adequacy of water delivery revealed that for the traditional operating system (without considering the economic perspective), the maximum values of the adequacy indicator were obtained for the upstream four canal reaches. On the other hand, the off-takes numbers of 1, 6, 5, and 12 got the maximum values of the adequacy indicator when the proposed operation-economic framework was applied for the canal system.

In this research, the impact of the Alagol wetland on the water treatment of Atrak River was studied. From June, 2016, to May, 2017, on the fifteenth day of the month, four samples of water were collected from the middle and the outlet of the wetland. Also, the wetland was fed only in the months of September, November and February. The parameters of acidity, electrical conductivity, phosphate, nitrate, dissolved oxygen, biochemical oxygen demand, chemical oxygen and ammonia were measured. The water pH at the entrance and exit was significantly different. EC was higher at the entrance, and its value was decreased in the middle and output. DO in the outlet of the wetland was higher than that in the middle and inlet, indicating the improved water quality and high dissolved oxygen in the wetland output. NO₃, NH₄, PO₄, BOD and COD were higher at the entrance to the wetland; also, it was decreased in the outlet and middle, and the difference was significant. Further, according to the results of September, November and February, which were fed to the wetland, water quality in the middle and outlet of the wetland was improved toward the entrance of the wetland. According to the results, Alagol wetlands could reduce the phosphorus, ammonia, BOD, COD and DO, and their concentrations were lower than the limit. However, given that the salinity at the entrance of wetland was too high, its amount in the output was higher than the standard limit and the wetland could not significantly reduce salinity. The results of this study showed that that of water pollution in the inlet, except that the dissolved oxygen parameters and the temperature were high and decreased in the middle outlet. Due to the quality of the wetland outlet, Alagol wetland water could be used for fish farming centers.

Growing concerns about water pollution and its potentially harmful effects on human being have stimulated serious efforts to develop reliable biological monitoring techniques. The bioluminescent analysis is one of the most promising approaches for the biomonitoring of the environment, due to the sensitivity of the luminescent system to even micro quantities of the pollutants. The aim of the current study was to assess the petroleum compounds toxicity using Vibrio fischeri bacterium. The growth pattern of the bacterium was determined in photobacterium broth using the optical density measurement at 600 nm, which showed the optimum growth time of 16-18 hours after inoculation. In this research, the effects of environmental parameters such as temperature, pH and various concentrations of oil on the growth and luminescence of Vibrio fischeri were examined. The results revealed that the optimum growth conditions of the bacterium after 16 hours included the temperature of 25 °C and pH 7. Besides, the growth and luminescence intensity of Vibrio fischeri were a function of total petroleum hydrocarbon concentrations in the medium, which were significantly reduced in oil concentrations by more than 4% w/v. Therefore, the Vibrio fischeri could, therefore, have the potential for monitoring of petroleum pollutants in the aqueous media.

In order to plan and manage the land and its changes, it is necessary to identify and evaluate the factors affecting it. Land use / cover changes are one of the main factors in global environmental change that is defined as a change in the type of land use; it is one of the major factors changing hydrologic flow, land erosion and destruction of biodiversity. The main purpose of this study was to assess the trends of land use changes in Beheshtabad Watershed of Chaharmahal and Bakhtiari Province with an area about 3847 square kilometers by using remote sensing and GIS during a 25-year period. In this research, first, analyzing and pre-processing the satellite images of Landsat 5 TM sensors from 1991 and 2008 were done, and Landsat 8 of OLI sensor of 2016 was applied. Then, by using the hybrid classification method, 5 land use classes including pasture lands, urban-building lands, agricultural lands, garden lands and bare lands, land use maps for the three time periods were prepared. The overall accuracy of the obtained land use maps for 1991, 2008 and 2016, was 92.17%, 94.29% and 93.41%, respectively, indicating the acceptable accuracy of the maps. Then, the process of land use change and the contribution of each land use classes and the percentage of changes in each land use class were determined in two study periods. The results of this study showed some changes occurred in the studied watershed. The total area of pasture lands during two periods indicated the decreasing trend, but urban-building and garden lands during two periods represented the increasing one. Agricultural lands during the first period indicated the decreasing trend and during the second period showed the increasing trend, while bare lands during the first period showed the increasing trend and during the second period, reflected the decreasing trend. In general, it should be noted that in the Beheshtabad watershed, we could see an increase in the replacement of pastures by urban-building class, rainfed agriculture, gardens, and bare lands, the incidence of destruction in the region.

Understanding the quality of groundwater resources, which are the largest available freshwater reservoir, is one of the needs in planning and developing water resources. The purpose of this research was to study the quality changes of groundwater resources in the upstream aquifers of Zayandehrood Dam (1995-2016) and to evaluate water quality in terms of drinking and agricultural consumption and evaluation of IRWQIGC. For this purpose, EC, TDS, SAR, PH, TH, Cl, CO₃, Ca, Mg, Na, K, HCO₃ and NO₃ parameters and heavy elements including zinc, copper, lead, cadmium and arsenic were investigated from laboratory samples. In the upstream aquifers of the Zayandehrood Dam, the water classification was mainly agricultural in the C2-S1 range, and it was generally acceptable in the drinking classes. The amount of heavy elements was allowed. The average amount of nitrate in the Chehelkhaneh, Damanehdaran, Boein-Miandasht and Chadegan aquifers was calculated to be 43.77, 48.08, 35.53 and 26.36 mg / l, respectively, and the maximum nitrate levels in these areas, however, were often exceeded. Nitrate zoning and IRWQIGC were performed by the kriging method. The lowest index values, which fell into relatively poor classes, were in the south and southwestern parts of Boein-Miandasht and south and south-west of the Chehelkhaneh, and in the central parts of Damanehdaran, and the south of Chadegan.

Due to the limited water resources and growing population, food security and environmental protection have become a global problem. Increasing water productivity of agricultural products is one of the main solutions to cope with the difficulties. By optimizing applied water and nitrogen fertilizer, the pollution of groundwater could be deceased and the water productivity could be increased. The aim of this research was to determine the relationships between water productivity (IRWP) and water use efficiency (WUE) and different amounts of applied water (irrigation + rain fed) and nitrogen (applied and residual). This study was conducted on wheat (Triticum aestivum L., cv. Shiraz) in Shiraz University School of Agriculture, based on a split-plot design with three replications, in 2009-2010 and 2010-2011 periods. Irrigation treatments varied from zero to 120% of full irrigation depth, and nitrogen fertilizer treatments varied from zero to 138 kg ha^-1 under basin irrigation system. The experimental data of the first and second years were used for the calibration and validation of the proposed relationships, respectively. The calibrated equations using the dimensionless ratios of irrigation depth plus rainfall, actual evapotranspiration and nitrogen fertilizer plus soil residual nitrogen to their amounts in full irrigation and maximum fertilizer amounts were appropriate for the estimation of water productivity and water use efficiency. The values of the determination coefficient (R²) for water productivity and water use efficiency (0.88 and 0.93, respectively), and the values of their normalized root mean square error (NRMSE) (0.2 and 0.13, respectively) showed a good accuracy for the estimation of IRWP and WUE.

The Plant Water Resistance Index (CWSI) is a tool that can be used for the rapid monitoring of plant water status, which is a key requirement for the accurate product irrigation management.The purpose of this study was to calculate the CWSI index for bean hares in the Khorramabad region for two methods of surface irrigation and drip tape ‎irrigation. For this purpose, a design was implemented in the form of randomized complete block design and split plot experiment. The main factors included drip tape irrigation (T) and surface irrigation (F), and the cultivars of Chibi cultivars including COS16 (C), Sadri (S) and diluted (K) served as sub-plots. By using the field measurements, the position of the upper and lower base lines was estimated for each treatment in different months and used to calculate the CWSI index. The results showed that CWSI values calculated in the surface irrigation during plant growth period were always higher than those in the drip tape irrigation. The highest value of CWSI index was obtained for the Sadri variety, which was equal to 0.20 and 0.26, for the type and surface method, respectively. Statistical analysis showed that the effect of irrigation method on the amount of water stress index was significant at 5% level, but there was no significant difference between different cultivars. According to the results of this study, the threshold values for CWSI were considered to be 0.19 and 0.24 for surface and drip tape ‎irrigation respectively, and relationships were presented based on the differences in vegetation and air temperature to determine the irrigation time.

One of the most important and complex processes in the watersheds is the identification and prediction of surface water changes. The main processes associated with surface water include precipitation, percolation, evapotranspiration and runoff. In this research, the semi-distributed model, SWAT, was used to simulate ground water and surface water in Semnan catchment in a monthly scale. A sensitivity analysis was perfomed to evaluate and demonstrate the influence of the model parameters on the four major components of water budget including surface runoff, lateral flow, groundwater and evapotranspiration. River discharge data from 2004 to 2014 were used for the calibration and those of 2014 to 2016 were applied for the validation. The results of sensitivity analysis showed that the most sensitive parameters were: SoL_K(Saturated hydraulic conductivity), CH_K2 (Effective hydraulic conductivity in main channel), RCHRG_DP(Deep aquifer percolation fraction and CN2 (Moisture condition II curve number). The simulation accuracy using Nash-Sutcliffe and coefficient of determination for Shahrmirzad, Darjazin, and Haji Abad hydrometric stations was about 0.60 to 0.80 and 0.80 to 0.90 for the calibration and validation period, respectively, showing a good performance in the simulation of river flow. According to the water balance results, about 87.6% of the total inflow into the watershed was actual evapotranspiration, 3% was surface run off, 3% was percolation, and the rest was related to the soil moisture storage.

Estimating the ecological water footprint and the virtual water trade in different agricultural crops in arid and semi-arid regions can help better manage the limited water resources.This research calculated temporal and spatial ecological water footprint of rain-fed and irrigated almond production in national and provincial scale using during 2008 to 2014. The results show that annual average water footprint in rainfed almond is 9.2 m³/kg, which the share of green and grey water is 72% and 28%, respectively which Ilam and Kohgiloyeh & Boyerahmad have a largest share in green water footprint with 91% and 90%, respectively. In adition to, in irrigated almond, the annual average water footprint is 11.4 m³/kg, which the share of green, blue and grey water is 0.19%, 71% and 10%, respectively. Sistan & Balouchestan, Khuzestana and Hormozgan have the highest share in blue water footprint. The total volume of water footprint of rain-fed and irrigated almond production is 1923 and 8242 MCM, respectively. Also, results show that about 92 percent of the total volume virtual water (equivalent to 9343 MCM per year) in almond production, has been exported to other countries through the virtual water trade.