مجله تحقیقات آب و خاک ایران
سال چهل و نهم شماره 2 (پیاپی 34، خرداد و تیر 1397)

Earth dams as controlling structures of surface flows and floods, must can store the water and prevent of water infiltration from their bodies and resist against forces. Important problem in designing earth dams that constructed with available materials, is determination of design that have expected performance with adequate safety and minimum cost. Because investigating and analyzing all possible options for determination best design requires to spend many of time and cost, designing the earth dams can be formulated as optimization problem. In this study, nonlinear programming model has been presented for designing earth dams optimally with the aim of minimizing the section area of dam (volume of materials that consumed in the dam length unit). Optimization was performed by applying constraints that ensure the safety of slopes that mathematical equations for approximation the values of factors of safety of slopes are defined as the new regression equations. . In order to find the optimal solution, shuffled complex evolution (SCE) algorithm was developed by programming. In addition to previous optimization, design variables were optimized using LINGO software. Then initial design of Barzok earth dam has been presented and performance of the proposed model in optimal designing of earth dams has been studied. Result showed that optimization methods used in this study present same estimation of optimal solution and obtained results from running the SCE optimization model and LINGO model showed that these two optimization methods in the optimization of dam section have same performance. The value of minimum objective function that's mean area of Barzok dam section was determined equal to 2725.3 m2 that in primary design, area of dam section is equal to 4400.7 m2. Therefore dam volume %38 has been reduced that is significant value.

To evaluate biomass production and cadmium (Cd) accumulation and translocation in three varieties of cabbage a factorial pot experiment with completely randomized design and three replications was performed in the greenhouse. Experimental treatments consisted of six levels of soil contamination to Cd (0, 10, 25, 50, and 100 mg Cd/kg soil from the cadmium sulfate [3Cd(SO4)×8H2O] source) and three varieties of cabbage (Brassica oleracea var. acephala L., Brassica oleracea var. italica L. & Brassica oleracea var. capitata L.) which were examined in triplicate. The Analysis of variance of data showed that the treatments had significant effects (P

Deficit irrigation and suitable choice of variety are essential optimization methods for water consumption in irrigated special in arid and semi-arid area. In order to, an experiment was conducted in a split plot arrangement based on randomized complete block design with three replications in Moghan plain under field condition at 2015 and 2016 years. Main-plot was Normal irrigation (IR1), 80 percent of full irrigation (IR2), 70 percent of full irrigation (IR3) and 50 percent of full irrigation (IR4). Cultivar included Super Bita (Cul 1), 08 (Cul 2) and Matin (Cul 3) as a sub-plot. The results of comparing the means of the data demonstrated that deficit irrigation decreased water productivity and yield of all cultivars and increased quality characteristics (TSS, present C Vitamin and pH) of all cultivars. Therefore, 08 was the best variety under normal irrigation and water deficit conditions about yield and Super bita was the superlative variety about quality characteristics to the deficit irrigation in Moghan Plain.

Flexibility indicates the status of water supply, so that by increasing this index, the status of the water supply system will be better and periods of crisis will be going across with the least risk. The purpose of this research is the evaluation of flexibility of Gharanghu reservoir system (East Azerbaijan) in terms of climate change (2040-2069) for the three status’s (100, 85 and 70 % of water demand supply) in order to identify and manage periods of crisis. Climatic pre-processing for the present study is performed by HadCM3 (A2 emission scenarios) that those are as an input to the simulation models of inflow to the reservoir (IHACRES model) as well as water demand model (Cropwat model). The results show that the long-term average annual inflow volume in future (30-year) will decrease about 25 % compared to the baseline period (1971-2000). However, the average annual water demand volume for crops increases by 20 % compared to the baseline. Next, in order to optimize the operation of reservoir for water supply, objective function as minimization of total squared monthly deficiencies is determined. For this purpose, LINGO 11.0 software (NLP method) was used for solving the problem. Results show that in climate change condition for first situation (with supplying 100 % of demand) relative to baseline period, reliability index will be decreased (by 20 %). The declines for the second and third situations are 16 and 2 %, respectively.

In order to study the effect of different irrigation managements and planting densities on Tarom Hashemi cultivar, an experiment was conducted in a randomized complete block design (RCBD) with three replications at Koshal-Lahijan in north of Iran during cropping seasons of 2014 and 2015. There were 5 levels of irrigation treatments in this research including: I1 = Full irrigation, I2 = Saturation, I3 = Irrigation with 8 days alternative before anthesis, I4 = Irrigation with 8 days alternative after anthesis, I5= Irrigation with 8 days alternative whole growth season) and there were 3 levels of density including, D1=15×15, D2=20×20, D3=25×25cm. Evaluation of calculated and measured yield was done with adjusted coefficient of correlation; T test of means; and by absolute and normalized root mean square errors (RMSE). Combined variance analysis showed that the effect of irrigation treatment and plant density on measured traits were significantly different (p

Despite modern scientific knowledge and computational power in hydrology, the key to properly addressing hydrologic uncertainty remains a critical and challenging one. Here, we applied lumped HBV hydrological model to describe the uncertainty in runoff prediction in Chehl-Chay watershed in Golestan province. We applied a new framework for uncertainty analysis that is rooted on ideas from predicting model residual uncertainty. The uncertainty calculated by local Errors and Clustering (EEC) is compared with estimates from two non parametric methods (quantile regression (QR) and random forest (RF)) and a parametric method (GLUE). Firstly, the model parameters were optimized by Shuffled Complex Evolution approach and model residuals of test data were computed. Fuzzy clustering in EEC is carried out by the fuzzy c-means method and employs four clusters, predictive discharges, observed discharges, rainfall values and residuals in study basin. The results of this case study show that the uncertainty estimates obtained by EES which is trained by SVM gives wider uncertainty band and RF gives narrower uncertainty band. The best overall uncertainty estimates according to the PICP, MPI and ARIL indices were obtained with QR and then EEC. In comparison with non-parametric, with respct to all indices nonparametric methods had better performance than GLUE method.

Studying sediment graph and sediment rating loops are as important and appropriate tools in analyzing sediment behavior with discharge changes and understanding the controlling role of discharge in sediment production during storms respectively. Therefore investigating the sediment behavior and variations in the form of sediment rating loops is so important in management planning and decisions. Accordingly the present study was therefore planned to analysis of sediment graphs and rating loops on consecutive storms under rainfall and soil erosion simulator condition. The simulations were done on a type of soil that was collected from Koujor region in Mazandaran Province. Towards this attempt, rainfall simulation experiments with intensities of 30 and 90 mm h-1were conducted in a set of 6 × 1 m plot with slope of 5 % during 6 consecutive storms. The results showed that total runoff increased with increasing of consecutive storms under rainfall intensities of 30 mm h-1 from 8.78 to 15.05 mm and under rainfall intensities 90 mm h-1 from 9.28 to 11.03 mm on the first and sixth storms respectively. But soil loss revealed more complex behavior than runoff so that occurred a sudden decrease in soil loss in fourth consecutive storm in compare with the other consecutive storms. Eventually, the results of rating loops on consecutive storms under rainfall intensities 30 and 90 mm h-1 reflected the variety of sediment output behavior in compare with discharge changes in different form of sediment rating loos including clockwise, counter clockwise and complex.

Responses of Olive self-rooted cuttings to irrigation water salinity and soil compaction in moisture of 0.9 saturation were studied. A loamy sand soil passed through a 4.75mm sieve, poured into PVC cylinders and compacted to achieve the desired compaction levels (bulk density of 1.3, 1.5 and 1.7 g cm-3). Then rooted olive cuttings were transplanted into the cylinders and were irrigated by waters with different salinities of 2, 5, 8 and 12 dS m-1 for five months. Instantaneous water use efficiency, electrolyte leakage, SPAD index and number of leaves to salinity of 8, and parameters of photosynthesis, stomatal conductance, transpiration rate, temperature difference between leaf and environment to salinity of 5 dS m-1 had no statistically meaningfull differences. Soil hypoxia decreases salinity tolerance mechanisms. With respect to olive plant growth, the bulk density of 1.3 g cm-3 was determined the optimum level of soil compaction for a loamy sand soil.

Knowledge of the watershed natural ability to produce runoff is an essential requirement toward optimal planning for runoff utilization. The aim of this paper is to evaluate HEC-HMS model using Soil Moisture Accounting (SMA) with continuous rainfall-runoff simulation in watershed and estimate the base flow contribution from direct runoff in Abolabbas watershed. It is possible to manage and plan water resources utilization by separating baseflow contribution and direct runoff from total runoff. SMA model use a series of storage layers including interception, canopy storage, soil storage profiles (upper layer storage and tension storage), and groundwater storage consider water loss in the watershed. Model calibration was performed using daily precipitation, evapotranspiration, temperature and river flow from 2001 to 2009 data and model verification was performed using 2010 to 2015 data. Results showed that HEC-HMS model with SMA have well consistently in simulation of daily runoff in wet and dry periods in Abolabbas watershed. Results showed that base flow contribution effect on total watershed runoff is more than direct runoff, in which the average percentage of total direct runoff and base flow runoff are 9.05 and 90.95 percent respectively. The results showed that on average, the percentage of runoff coefficient during the statistical period in Abolabbas watershed was 6.6 percent.

The effect of salinity and water deficit irrigation is one of the most important and prevalent stresses in the world, which prevents proper plant yield. In order to investigate the effect of salinity levels and amount of water needed for peanut, the experimental design was split factorial in a randomized complete block design with three replications in Guilan province during 2015 and 2016. The main irrigation management factor was 40 (WR4), 60 (WR3), 80 (WR2) and 100 (WR1) percent water requirements for irrigation management and sub-treatment including salinity with values of 1 (S1), 3 (S2), 5 (S3) and 7 (S4) ds m-1, and the subdivision included four almond cultivars: Guil (V1), Gorgani (V2), Jonobi (V3) and Mesri (V4). The results showed that the maximum yield of biomass in Mesri cultivar was with 100% water requirements and salinity of 1 dS m-1 in 2015 and 2016 was 12230 and 11110 kg ha-1. The highest pod yield in 2015 in Mesri cultivar was 100% water requirement and salinity one ds m-1 with 1710 kg ha-1. In 2016, the highest yield of pod (5403 kg ha-1) was obtained in 40% water requirement and 7 ds m-1 salinity. The highest amount of seed in Guil cultivar and in 100% water requirement and salinity of 1 dS m-1 in 2015 and 2016 were 1883 and 1710 kg ha-1, respectively.

Piano-Key weirs (PKW) and labyrinth weirs (LW) are nonlinear weirs that can increase the passing over flow magnitudes for a given width without increasing the water head. Arced configuration of this weir, improve the flow direction to the cycles And reduce inequality entering of flow to the various cycles. Arced labyrinth(ALW) and Arced piano key(APK) weirs are especially well used for spillway rehabilitation where larger probable maximum flow have required modification or replacement of the spillway. In the current paper, a total of 308 experiments were conducted on 15 laboratory models for analyzing the variations of APKW and ALW Hydraulic Performance through altering the geometric parameters, i.e. cycle arc angle(θ), weir height(P), crest shape, Magnification cycle(Lc-cycle/w), cycles width ratio(w/P), apex length(A) and compared with the LW, PK and linear weirs. By increasing the cycle arc angle and modifying this weirs, increased efficiency so that The average and maximum difference in discharge coefficient of ALW (θ=40o) than LW weirs are 12 and 21 percent, respectively and this difference are 25 and 40 percent between the APK (θ=40o) and PK weirs, respectively. Modified arc weirs are more efficient than their unmodified weirs. But with increasing Ht/P, values of their discharge coefficient connected to each other. Finally, by increasing the cycle arc angle, the superiority of piano key weirs are more than the labyrinth weirs.

This field experiment was conducted to investigate the effect of foliar application of zinc (Zn) in the form of ZnSO4 and Zn-Lys amino chelate on growth indices and yield of Behbahan onion at the Agriculture Research Station of Behbahan, Iran. The experiment was conducted in a randomized complete block design with four treatments and three replications. Foliar application treatments were: ZnSO4, Zn chelated with lysine (Zn-Lys), and free amino acid of lysine (Lys). A treatment with no foliar application of Zn and amino acid was considered as the control. Foliar application was performed at two stages, once at the early rapid vegetative growth stage and the other at the early bulbing. The results of growth analysis indicated that at all fertilizer treatments, the slow growth period lasted to 125 days after seed germination followed by the rapid growth period. The maximum leaf area index (LAI) (4.19), bulb growth rate (30.49 g m-2 day-1), crop growth rate (39.66 g m-2 day-1) and total and marketable yield of bulb (63.07 and 60.54 t ha-1, respectively) was obtained at the Zn-Lys amino chelate. Among different treatments, the pattern of dry matter accumulation showed that Zn-Lys amino chelate resulted significant increase of plant dry mass (62% over the control treatment), and this trend continued until the end of the growing season. A positive and significant correlation (P

In this study, the effect of three levels of 100, 70 and 50 percent of FC, moisture as major factor and two levels of absorbent as secondary factor in three repeats during middle growing of radish was assessed. The analyzed results showed that the effect of moisture and absorbents on volum, size and weight of gland, water used efficiency and total water used efficiency (gland shoot) were significantly in level 0.01. The more shoot height, root length, leaf number, wet and dry weight were 12.97 cm, 14.49 cm, 7.67 leaves, 8.47 gr and 0.51 gr, respectively. The less water used efficiency and total water used efficiency belonged to moisture 100 %. The more values of gland weight, water used efficiency and total efficiency were 12.07 gt, 6.36 and 11.93 kg/m3 in 13 gr vermicompost. The interaction of moisture and absorbent for wet and dry factors were 14.16 and 0.62 gr, water used efficiency and total efficiency were 7.25 and 12.46 kg/m3 in 75% level moisture and 13 gr vermicompost In 42.6 % of cases, the peak gland weight and water used efficiency and total efficiency related to interaction 75% moistute and 13 gr vermicompost. In 42.6 % of cases, the results showed that the more values of some factores belonged to interaction of 100% moisture with minimum vermicompost (13 gr) with 75% of FC moisture and level 13 gr vermicompost have not significant difference. So, it can be concluded that in 85.2 % of cases the effect of 75% FC with 13 gr vermicompost was suitable.

Due to importance of predicting groundwater table fluctuations as an important and key factor in agricultural activities, the main aim of this study is finding the model and effective factors in predicting groundwater table fluctuations by using CART tree algorithm in data mining package of "SPSS modeler 18.0 IBM", in Qazvin irrigating area during 15 years from 2001 to 2015. Input variables to the model were the degree of effectiveness of each piezometer, net water requirements, the amount of consumption in each piezometer, rainfall depth, inflow and outflow from Taleghan reservoir, cropping area, and inflow to the irrigation system, the model output as objective function is groundwater table fluctuations. The predictability of the model was determined by the criteria such as correlation coefficient and mean absolute error. The results showed that the performance of the CART algorithm in predicting water table fluctuations inside the irrigation system is better than the outside of it. Furthermore, the results show that the most important parameter effective in predicting groundwater table fluctuations inside of the irrigation system is inflow to reservoir.

The huge volume of saline agricultural drainage water and necessity of avoiding it's undesirable environmental side effects which caused by discharge to water bodies, beside critical situation caused by shortage of water availability, necessitated of planning and proceeding to depletion and reuse of such marginal waters. The objective of this study was assessing and evaluation of a laboratory made nano-polymeric membrane in rejection of sodium absorption ratio (SAR) and ralated cations in agricultural drainage water. The Nano-polymeric membrane fabrication was performed by using % 80 polyethylenes with film grade (PE020) and %20 polyolefin elastomer (POE) polymeric composition. Natural agricultural drainage water was collected from Khorramshahr irrigation & drainage project located in Khuzestan province. In this experiment, the effect of feed agricultural drainage water salinity and membrane permeability on reduce of Electrical Conductivity (EC), SAR, Na monovalent cation and divalent cations of Ca2 was studied. Experiments defined in five dilution levels of drainage water (0, 0.2, 0.4, 0.6 and 0.8). The characterization of the membrane showed that mean pore radius was about 0.778 nm, the thickness about 20 (µm) and membrane porosity was 36.42%. Salt rejection sequence was: CaCl2>NaCl>Na2SO4 which showed that the membrane is positively charged. The rejection rate of Na and Ca2 of agricultural drainage water in all dilution levels were between 39.76-50.71% and 19.34-40.95%, respectively. The rejection rate of EC and SAR were changed between 37.10-46.18% and 30.80-36.38 %, respectively. Finally, the efficiency of this laboratory-made Nano-polymeric membrane was compared with a commercial membrane (NF2, Spero). Results showed that despite of lower permeability of PE membrane, its EC rejection rate was higher than commercial membrane in all dilution levels.

The object of this research is the estimation of spatial distribution of three air temperature parameters at daily and monthly scales including minimum, maximum and mean temperatures at the Kurdistan province using MODIS sensor images setted on Aqua and Terra satellites. For this object, 8 synoptic stations at Kurdistan province were selected and for these 8 stations at 2013 and 2014, daily minimum, maximum and mean air temperature data and also land surface temperature at 4 daily times at these 8 stations for 2013 and 2014 years were extracted by processing on the MODIS sensor images. Afterwards, the multiple linear regression method was used to extract regional regression models for Kurdistan province between these 3 air temperature parameters and land surface temperature and to assesing the errors, cross validation based on the Mean Absolute Error, Mean Bias Error and Nash-Sutcliffe Efficiency coefficient was adopted. The results showed that it is a powerful relation between all of these 3 air temperture and land surface temperatures extracted by sattelite images. The results of cross validation showed an approperiate and reseanable agreement between the measured and estimated values of these 3 parameters at both daily and monthly scales so that the mean absolute error for minimum, maximum and mean temperatures were 2.7, 2.1 and 1.6 °C at daily scale and 1.9, 2. 1 and 1.1 °C at monthly scale, respectively. These results showed that it is possible to estimate these air temperature parameters at the places witout any meteorological stations with an approperiate and acceptable accuracy by extracting land surface temperatures of MODIS sensor for these places and applying the extracted regression models.

Recently, the use of copula functions as a practical and flexible tool for constructing joint probability distribution of multivariate hydrologic phenomena, such as flood, has attracted great attention of hydrologists. The main objective of this study is to extract and analysis of the joint and conditional return periods of some dependent characteristics of runoff hydrograph, including runoff volume, peak discharge, base time and time to peak discharge. These characteristics extracted from 60 flood events recorded in Valikbon hydrometric station, located in outlet of Kasiliyan reference watershed during 1975-2007. Three copulas, including Clyton, Ali-Mikhail-Haq and Frank were considered for constructing the joint distribution of the paired hydrograph characteristics. The Frank copula was selected as the best copula for constructing the joint distribution from paired characteristics of runoff volume and peak discharge of hydrograph and also runoff volume and base time of hydrograph. While the Clyton copula was recognized as the best copula for other two dependent characteristics, namely time of peak discharge and base time of hydrograph. After constructing joint distributions, several valuable information such as joint probability, joint and conditional return periods were calculated and plotted.

The current study was conducted at Sari county prior 2015 and 2016 seasons with split plot design with three main factors (irrigation interval) and three sub main factors (irrigation water amount) in a complete block design in three replications. The irrigation intervals were irrigation after 20, 35 and 50 mm evaporation from class A evaporation pan (respectively F-20, F-35 and F-50). The statistical analysis of data was conducted by SAS software using Duncan test. Due to the non-significant difference for seed performance (SP) trait between FI and PRD-75 treatments, it could be possible to save approximately 13% of water by applying PRD-75. The F20-FI and F20-PRD75 treatments had the best results for SP respectively. F20-PRD75 and F35-FI had the best results for oil performance.

Reduction the concentrations of arsenic labile fractions is very important because these fractions are directly related to its bioavailability. This study was carried out to assess the effects of maleic anhydride- styrene- acrylic acid copolymer on the motility and availability of arsenic and corn growth in contaminated soils. For this purpose a factorial experiment was conducted using a completely randomized design and three replications. The examined factors were the rates of application of acrylic acid copolymer (0, 0.05, 0.1 and 0.2%) and the levels of soil arsenic (0, 6, 12, 24, 48, and 96 mg/kg). Corn plant was used as a biological indicator for arsenic phytoavailability and before sowing, the concentrations of soil available arsenic were measured for all soil samples. After harvesting, the dry weights of aerial parts and roots and concentrations of arsenic and phosphorus of these parts were measured. The results showed that the concentrations of soil available arsenic and root and aerial parts arsenic increased as the concentration of soil total arsenic increased. Contamination of soil by arsenic increased the concentrations of phosphorus in root and decreased it in aerial parts. At all levels of soil arsenic, the application of acrylic copolymer significantly decreased the concentrations of arsenic in soil and in root and aerial parts of corn. The application of acrylic copolymer increased the dry weight of root by decreasing the accumulation of arsenic and phosphorus in plant root. It also increased the dry weights of aerial parts as a result of increased concentrations of phosphorus and reduced accumulation of arsenic. It is recommended that this acrylic copolymer to be used in reducing the mobility of arsenic in contaminated soils.

Need for groundwater in recent decades has led to the development of various strategies for managing surface water resources and proper use of groundwater. In this study, the groundwater aquifer model of Miandoab plain was prepared by MODFLOW-NWT model. After calibration and validation, three scenarios were investigated. In the first and second scenarios, increase of 10 % and 20% of irrigation efficiency in the plain and reduction of pumping from groundwater was applied, respectively. In the third scenario, preventing pumping water by pump engine from rivers of Siminehrood and Zarinehrood and providing water requirement from groundwater resources was applied. In the first and second scenarios, with increasing efficiency, total water consumption can be reduced from 924 MCM in current situation to 776 and 664 MCM, respectively. By providing 642 MCM of surface water, pumping water from groundwater could be reduced by 148 and 282 MCM relative to the current situation, respectively. The results showed that from amount of water that is no longer pumped, the amount of 34 and 41 MCM are exited as underground flow from downstream toward Lake Urmia, respectively, amount of 40 and 51 MCM are discharged into surface water resources, respectively, and the rest is stored in the plain. With continuing this approach after 5 years will lead to swamp in middle of plain. The amount of agricultural return water in current situation is 33% and in the first and second scenarios are 28% and 20%, respectively, which relative to the current situation have been decreased by 5% and 13%, respectively. In the third scenario, by increasing pumping from groundwater, the average level of groundwater went down by 1.5 and 3 meters after 1 and 5 years, respectively, but it provided 495 MCM to restore Lake Urmia after 5 years.