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Prof. Saeid Eslamian
Isfahan University of Technology, Water Enginnering, Faculty Member
- The University of New South Wales, Civil and Environmental Eng., AlumnusPrinceton University, Civil and Environmental Eng., Department Memberadd
- 3D GIS, Soil, French Studies, Water, Natural Resources, Hydraulics, and 98 moreWind Energy, Conservation, Alpine Research, Environmental Studies, Risk Governance, Geography, Music, Engineering, Tourism Studies, Mathematics, Geomatics, Remote Sensing, Persian Literature, Water Safety/Drowning/Lifesaving, Agriculture, Analysis (Mathematics), Tropical Ecology, Environmental Engineering, Agricultural Engineering, Civil Engineering, Ecological Engineering, Ocean Engineering, Urban Geography, Applied Mathematics, Mathematical Statistics, Optimization (Mathematical Programming), Probability Theory, Statistics, Environmetrics, Air Quality, Tourism Management, Coastal Engineering, Statistical Computing, Multivariate Statistics, Climate Change, Ocean Mapping, Environmental Remediation, Environmental Geology, Wetlands, Hydrology, Torrential Hydraulics, Maritime Hydraulics, Renewable Energy, Biological Fluid Dynamics, Music Video, Suburban Studies, Agroecology, Sustainable agriculture, Energy Engineering, Geotechnical Engineering, Irrigation, Optimization (Mathematics), Linear Programming, Oceanography, Geomorphology, Geophysics, Operations Research, Fluid Dynamics, Meteorology, Water Treatment, Agricultural Water Management, Water Pump, Water Resources (Geography), Drinking Water Quality Standards, Arsenic Contamination in Ground Water, Biological Treatment Of Sewage Water, Urban Water Consumption, Water Reuse, Ground Water Exploration, Melt-water pulses, Ballast water treatment, Water and Energy, Soil and Water Engineering, Water quality, Household Water Treatment Systems, Access To Water, Brackish Water, Water resources, Mine Water, Water Purification, Water-Energy Nexus, Water Availability, Water Resources (Engineering), Atmospheric Water Vapor, Fluoride contamination in ground water, Water and wastewater treatment, Water History, Water Engineering, Water Quality (Engineering), Urban Water Systems, Surface Water Modeling, Sustainable Water Resources Management, Agricultural Economics, Soil and Water Enginnering, See this please!, Unsaturated soil, Environmental Sustainability, and Rain Water Harvestingedit
- Professor Saeid Eslamian has been supervised by Prof. David H. Pilgrim during his Ph.D. study in School of Civil and ... moreProfessor Saeid Eslamian has been supervised by Prof. David H. Pilgrim during his Ph.D. study in School of Civil and Environmental Engineering, University of New South Wales, Sydney, Australia. Eslamian has published a large number of scientific books, reports, journals and conference papers. He has been successful in a number of research grants. He is founder and chief editor of two Journals: Journal of Flood Engineering (JFE) and International Journal of Hydrology Science and Technology (IJHST) and technical reviewer for 13 ISI Web of Science scientific journals.
His research interests fall in urban hydrology and water resource management. These could be categorized in the following areas:
a. Global Warming, Climate Parameter Variability and Climate Changes in Urban Area.
In this way, the effect of land use change and urbanization on rainfall, runoff, evapotranspiration and in general on Climate Change could be investigated. Integrated urban water management is very important in a changing environment. Due to this fact that adaptation to climate change is a new focus of IPCC, the new and optimum strategies in urban environment play a key role toward urban sustainable development.
b. Risk Analysis of Natural Hazards for Management and Insurance.
These include flood, low flow, extreme rainfall, wind, water pollution and earthquake. Geostatistics methods and regionalization techniques help us to estimate the hydrological and physical statistics in ungauged sites. Innovations including applications of Univariate L-moments and Multivariate L-moments, Copula. for the parameter zoning and including the effect of dependency are welcome.
c. Developing New Drought Indices with emphasize on urban water management.
Many drought indices have been developed for water management in dry periods. But, these indices have some deficiencies regarding types of included variables and their combinations.
d. Sustainable development of Water Resources using Water Reuse Artificial recharge modeling with emphasis on water quality along with constructed wetlands is encouraged to be investigated in depth. Surface Water and Groundwater Interaction could be studied using new software’s such as GROUNDWATER VISTA and GEOHYDROSPHERE.
His teaching experiences are mainly Surface Runoff Hydrology, Engineering Hydrology, Groundwater Hydrology, Water Resources Management, Water Resources Planning and Economics, Meteorology and Climatology in Undergraduate Level and Evapotranspiration and Water Consumption, Multi-purpose Operation of Water Resources, Advanced Hydrology, Arid Zones Hydrology, Rangeland Hydrology, Groundwater Management, Water Resources Development, Hydrometeorology in Postgraduate Level.
Prof. Eslamian recently appointed as Chief Editor of 2012 3-volume Handbook of Engineering Hydrology by Taylor and Francis (CRC Group).edit - Prof. David H. Pilgrimedit
This research presents recent advances on morphodynamic modelling over gravel dunes. Boundary-layer separation over gravel fixed dunes is investigated by particle image velocimetry (PIV) and acoustic Doppler velocimetry (ADV). Using the... more
This research presents recent advances on morphodynamic modelling over gravel dunes. Boundary-layer separation over gravel fixed dunes is investigated by particle image velocimetry (PIV) and acoustic Doppler velocimetry (ADV). Using the measurements of flow over dunes for different conditions at laboratory scale, advantages of PIV application are investigated for the flow pattern in the lee angle of 38 degree. To compare the experimental results with numerical models over dunes, the 3D numerical model (SSIIM) is applied in this study. The results reveal that the numerical model successfully simulate flow over dune compared with PIV data. Although ADV application near the bed indicates weak performance for high discharge and low water depth, PIV results present more agreement with the numerical model in this region.
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So far, many researches have been done on the effects of hydrocarbon (especially oil) contamination on such soil strength and geotechnical indices as cohesion, angle of internal friction, shear strength, permeability, dry density, and so... more
So far, many researches have been done on the effects of hydrocarbon (especially oil) contamination on such soil strength and geotechnical indices as cohesion, angle of internal friction, shear strength, permeability, dry density, and so on. In the present research, effort has been made to model buried concrete piles with known dimensions, and study the effects of the length and diameter ratios (L/L 0 and D/D 0) on their load bearing capacity using the results of previous researches, the values of the geotechnical and strength parameters of oil-contaminated silty sand (SM) specimens, and the PLAXIS 2D Software. Results have shown that with an increase in the percent hydrocarbon contamination, the ultimate load bearing capacity of a pile follows a gradual decreasing trend. Again, an increase in the pile length ratio causes an increase in the load bearing capacity, but one in the diameter ratio causes a decrease in the bearing capacity. Keywords: hydrocarbon contamination; soil strength and geotechnical indices; length and diameter ratios; load bearing capacity; silty sand; PLAXIS 2D. Reference to this paper should be made as follows: Hafshejani, A.S., Hajiannia, A. and Eslamian, S. (2017) 'Effects of homogeneous hydrocarbonic contamination on the bearing capacity of in-situ concrete piles buried in silty sand', Int. He is an expert in the effect of oil contamination on bearing capacity of piles and soils, especially in oil contamination transport in soil medias. He published eight papers in national conferences held in Islamic Republic of Iran and one article in international journals.
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To evaluate the performance of Adaptive Neural-Based Fuzzy Inference System (ANFIS) model in estimating the efficiency of Pb (II) ions removal from aqueous solution by ostrich bone ash, a batch experiment was conducted. Five operational... more
To evaluate the performance of Adaptive Neural-Based Fuzzy Inference System (ANFIS) model in estimating the efficiency of Pb (II) ions removal from aqueous solution by ostrich bone ash, a batch experiment was conducted. Five operational parameters including adsorbent dosage (Cs), initial concentration of Pb (II) ions (Co), initial pH, temperature (T) and contact time (t) were taken as the input data and the adsorption efficiency (AE) of bone ash as the output. Based on the 31 different structures, 5 ANFIS models were tested against the measured adsorption efficiency to assess the accuracy of each model. The results showed that ANFIS5, which used all input parameters, was the most accurate (RMSE = 2.65 and R2 = 0.95) and ANFIS1, which used only the contact time input, was the worst (RMSE = 14.56 and R2 = 0.46). In ranking the models, ANFIS4, ANFIS3 and ANFIS2 ranked second, third and fourth, respectively. The sensitivity analysis revealed that the estimated AE is more sensitive to the contact time, followed by pH, initial concentration of Pb (II) ions, adsorbent dosage, and temperature. The results showed that all ANFIS models overestimated the AE. In general, this study confirmed the capabilities of ANFIS model as an effective tool for estimation of AE.
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Water scarcity is a worldwide problem and the best solution is to make an efficient use of water in the agricultural sector. The use of deficit irrigation is a suitable method in water scarcity conditions. In this chapter, two... more
Water scarcity is a worldwide problem and the best solution is to make an efficient use of water in the agricultural sector. The use of deficit irrigation is a suitable method in water scarcity conditions. In this chapter, two optimization models are explained for surface deficit irrigation to maximize the net income and application efficiency and minimize the total costs. Therefore, it developed the production function of the crops and a model for simulation of advance phase in surface irrigation. The output of these models gives us the design variables of surface irrigation. Two case studies will be presented to show the result of application of the models for a given region of Iran. These studies validate the fact that deficit irrigation is an efficient method in water scarcity conditions. By: Dr. Kaveh Ostad-Ali-Askari
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This investigation develops a new method, called the "Region of Influence" (RI) approach, to improve at-site estimates of extreme flow quantiles based on statistical and physical characteristics of the surrounding stream gauging stations.... more
This investigation develops a new method, called the "Region of Influence" (RI) approach, to improve at-site estimates of extreme flow quantiles based on statistical and physical characteristics of the surrounding stream gauging stations. One main advantage of this approach over the traditional regional methods is that geographically dispersed sites in a "Region of Influence" of the reference site, are more likely to be independent of each other. Such "regions" are more hydrologiclly homogeneous than the traditionally defined regions. Statistical properties of flood data are needed for inclusion in the similarity distance algorithm and for estimating flood quantiles. Using the partial flood series, a number of distributions were tested by three fitting tests with data sets from 61 stream gauging stations located in south-eastern New South Wales (NSW), Australia. The successful distributions were the Log Pearson Type 3, the Wakeby, and the Pearson Type 3 for specific ranges of log skew. The criteria for choice of a set of the statistical and physical attributes of catchments and the effect of interaction between attributes on the defined regions are determined. The choice of the threshold value of the similarity distance and the associated sensitivity are discussed. The identification of regional outlier sites and their effects on standardization process of the attributes are also investigated. The effect of the combination of physical attributes with statistical one on the defined regions are evaluated. The associated flood frequency curves with the RI approach based on different combination of attributes are compared with observed at-site estimates. The steps for application of the RI approach to the gauged and ungauged sites are detailed. As a consequence, a physically-statistically based and a physically based RI approach has been recommended for improvement or estimation of flood quantiles of the gauged and ungauged sites in south-eastern NSW, respectively. Region of Influence Approach / Australia / Flood Frequency / Rainfall / Runoff / Catchments Djokic, Dean, Supervisor University of New South Wales, School of Civil Engineering, Dept. of Water Engineering, Sydney, NSW, Australia University of New South Wales, School of Civil Engineering, Dept. of Water Engineering, Sydney, NSW, Australia
Remote sensing (RS) and geographic information system (GIS) techniques have been extensively used over the world for the study of chronological changes in land use/land cover (LULC) and land surface temperature (LST). Moreover,... more
Remote sensing (RS) and geographic information system (GIS) techniques have been extensively used over the world for the study of chronological changes in land use/land cover (LULC) and land surface temperature (LST). Moreover, understanding the relationship between them is the most important to manage lands. This study explores the application of RS/GIS for identifying LULC change and assessing its impact on LST using temperature-vegetation index (TVX) space in the east sub-basins of Urmia Lake basin, Iran. The results showed that most changes due to agricultural activities were observable as the pixel migrated from the high temperature-sparse vegetation condition to the low temperature-dense vegetation condition from 1989 to 2002; while, in addition to agricultural activities, due to urbanisation and human activities, the pixel migrated from the low temperature-dense vegetation condition to the high temperature-dense 196 F. Fathian et al. vegetation condition from 2002 to 2011 in the TVX space for entire case study. In general, the LULC change is a significant factor for LST increase or decrease, and LST changes mostly related with LULC changes in the study area. Reference to this paper should be made as follows:
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An optimisation model was derived for deficit irrigation to study four scenarios of water price-irrigation system combinations. The nonlinear objective function was optimised within a three-dimensional decision domain including: deficit... more
An optimisation model was derived for deficit irrigation to study four scenarios of water price-irrigation system combinations. The nonlinear objective function was optimised within a three-dimensional decision domain including: deficit irrigation ratios of wheat and tomato; and cropping area ratio of wheat to tomato. Four scenarios were employed regarding two pricing configurations including subsidised and non-subsided water prices and two irrigation systems as well. The results of the integrated optimisation model showed that the optimised deficit irrigation ratios are not changed by altering water price in each irrigation system. However, deficit irrigation of wheat crop increases net-benefit of farmers in subsidised price while, the net-benefit of farmers is not increased under the deficit irrigation of wheat crop with non-subsided water price and tomato crop in both price configurations. Sensitivity analysis of the model showed that annual tomato cropping costs and price are the most sensitive parameters in the optimisation. Reference to this paper should be made as follows: Banihabib, M.E., Zahraei, A. and Eslamian, S. (2015) 'An integrated optimisation model of reservoir and irrigation system applying uniform deficit irrigation', Int.
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Innovative water technologies such as rainwater harvesting have the potential to improve water supply. Rainwater harvesting is an ancient technique enjoying a revival in popularity due to the inherent quality of rainwater and interest in... more
Innovative water technologies such as rainwater harvesting have the potential to improve water supply. Rainwater harvesting is an ancient technique enjoying a revival in popularity due to the inherent quality of rainwater and interest in reducing consumption of treated water. Integrating indigenous knowledge of rainwater harvesting with new findings of researchers can make appropriate opportunities to solve water scarcity in the regions facing highly variable rainfall pattern both spatially and temporally such as the current study area (Iran). These traditional water-harvesting systems have been sustainable in local area for many years. Interaction between modern knowledge and past experience about rainwater harvesting systems has been studied in order to increase efficiency and quality of implementing rainwater harvesting systems. This paper explores how indigenous knowledge is used by farmers to identify potential sites for rainwater harvesting and also how they construct these systems. Key elements such as group discussion method; rainwater harvesting conference, participatory workshop and field visit are parameters that have performed to gather indigenous and modern information. Implementing geographic information system could be an important tool to collect and upscale the utility of diverse indigenous knowledge in the decision-making process.
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In this study precipitation and standardised precipitation index (SPI) trends were analysed using linear regression, Mann-Kendall and Spearman's Rho tests at the 5% significance level. For this purpose, meteorological data from 20... more
In this study precipitation and standardised precipitation index (SPI) trends were analysed using linear regression, Mann-Kendall and Spearman's Rho tests at the 5% significance level. For this purpose, meteorological data from 20 synoptic stations in south of Iran over the period 1985–2013 were used. According to results two main drought periods were detected (1998–2003 and 2010–2012), while the extremely dry year was recorded in 2010 at all stations. Seasonal analysis of precipitation showed that trends in spring and winter precipitation series is decreasing. The decreasing precipitation trend was found in the summer and autumn series at 77.7% and 64% of the stations, respectively. Significantly trend was not found in the SPI-12 series at the 5% level. Results showed that base on Mann-Kendal method number of stations with decreasing trend in monthly and seasonal perception is more than Spearman's Rho tests and this method is more than percent linear regression.
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Because of the requirement to just one input data, the basic sediment rating curve (SRC) method is the most recognised method for the study of river sediment load. Beside its advantages, this method suffers from low accuracy, especially... more
Because of the requirement to just one input data, the basic sediment rating curve (SRC) method is the most recognised method for the study of river sediment load. Beside its advantages, this method suffers from low accuracy, especially for upper limit of sediment load values which is leading to the reduction of its reliability. In this study, sediment data recorded in four hydrometry station located in Gorgan Gulf basin are used to investigate and compare the accuracy of minimum variance unbiased estimator (MVUE) and beta coefficient as two correction methods. Visual criterion and two goodness of fit tests, namely mean square error (MSE) and model efficiency (ME) were applied to compare the results of SRC estimations. Visual and goodness of fit tests showed both correction methods particularly beta coefficient method improve the SRC estimation especially for upper limit of river sediment load in three of the four understudy stations.
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In this study, the performance of linear and nonlinear models for the estimation of reference evapotranspiration was examined. To evaluate the performance of nonlinear models, we used the radial basis function (RBF) neural networks and... more
In this study, the performance of linear and nonlinear models for the estimation of reference evapotranspiration was examined. To evaluate the performance of nonlinear models, we used the radial basis function (RBF) neural networks and genetic programming (GP), and the multiple linear regression (MLR) method was used for linear models. Using these three methods, monthly evapotranspiration was calculated for Isfahan region in a 26-year period. Comparison of the results for nonlinear and linear models showed that the GP3 model by the coefficient of determination of 0.99 and root mean square error (RMSE) of 0.21, has the best performance among the studied models. Instead, the RBF model training speed is higher than the GP model. Furthermore, the results showed that the MLR model has good performance in estimating evapotranspiration and there is no significant difference between the accuracy of the MLR and RBF method, but the accuracy of GP model is better than the RBF and MLR models. The results showed that the reference evapotranspiration could be estimated with high accuracy by both linear and nonlinear models for the study area.
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The effects of irrigation with treated wastewater on soil chemical and physical properties have been studied in many researches, but a few studies have done about waste water flow on the soil surface. In this study flow hydraulic of... more
The effects of irrigation with treated wastewater on soil chemical and physical properties have been studied in many researches, but a few studies have done about waste water flow on the soil surface. In this study flow hydraulic of wastewater on soil surface was investigated and magnetic field effects on it was also studied. This research was done in the field with furrows (length of 42m, width of 60cm, depth of 25cm and slope of 0.1%) in Isfahan University of Technology and were used three water quality treatments consists of fresh water (FW), wastewater (WW) and magnetized wastewater (MW). Magnetic field was created by three magnets with constant magnetic field intensity of 10mili-Tesla for each one. Basic differences between three water treatments were in biological parameters (Chemical oxygen demand (COD), Total-coli form) and total suspended solids (TSS). The Collected data were included of advance and recession time, inflow and outflow rates with four replications and five irrigation events for each treatment (overall 60 practices), in a randomized complete block design. The inflow rate for furrows was determined 0.8 lit/sec. The results showed magnetic field have not a considerable effect on the physical and chemical characteristics of the wastewater, though it changes oxygen demand and especially total coli forms. Also no significant difference was observed between the effects of water quality treatments on water infiltration characteristics, consist of basic infiltration rate (f o)and mean infiltration rate in two 30 minutes' time intervals (0-30 and 30-60 minutes),but in mean infiltration rate in 0-30 interval, mean relative changes for the WW and MW were about twice of the FW. Mean infiltration rate of the FW has also less reduction than WW and MW in these intervals. However, scrutinizing of parameters variations in charts showed that WW and MW treatments relation to FW ones created more changes in downtrend of " f o " during irrigation season and magnetic field effect was inconsiderable. The " f o " in WW and MW was more than FW mostly. It was found that magnetic field causes increasing of the " f o " in MW related to WW. Similar results also were found in two time intervals of infiltration process. Also excluding depletion time phase, evaluated time parameters, including advance time to furrow end, time to reach the " f o " and recession duration had not difference significantly influenced by water quality treatments, but values of advance time and time to reach the " f o " for WW and MW than FW were higher mostly. According to regressions equation between water quality parameters and flow hydraulic parameters, were found a negative correlation between " f o " , mean infiltration rate for 0-30min and 30-60min ranges and advance time with TSS and irrigation number; and a positive correlation between these parameters with COD ; also a negative correlation between time to reach the " f o " and depletion time with COD ; and a positive correlation between these parameters with TSS and irrigation number. In parameter of recession duration, positive correlations are with irrigation number and COD ; and negative correlation is with TSS .
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This paper reports the development of a new method for land grading computation having time saving and simplicity advantages. The conventional method uses the trial and error process to determine the desired cut-fill ratio, which is... more
This paper reports the development of a new method for land grading computation having time saving and simplicity advantages. The conventional method uses the trial and error process to determine the desired cut-fill ratio, which is cumbersome and time-consuming. In developed method, the trial and error process is not necessary. Instead, the Excel Solver was applied to determine the plane equation of land grading, and minimize the earthwork volume based on a desirable cut-fill ratio. Then, results of the new method for three data sets were compared with the conventional and genetic algorithm (GA) methods. In all of the data sets, results of the new method were better than two other methods. The cut-to-fill ratio and cut volume were less in new method than others.
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In this paper we investigated the effects of fresh water (F as a control), wastewater (W) and magnetized wastewater (M) on furrow erosion. Experimental design was randomized complete blocks consisting of four replication blocks and three... more
In this paper we investigated the effects of fresh water (F as a control), wastewater (W) and magnetized wastewater (M) on furrow erosion. Experimental design was randomized complete blocks consisting of four replication blocks and three water quality treatments. Five irrigation events with 4 days' irrigation interval were practiced in each furrow. The erosion was monitored and measured in the second, fourth and fifth irrigation events for each furrow. Water quality parameters measured during the irrigation ventsd included cations, anions, EC, pH, total-coliform, TSS, DO and COD. The applied intensity of the magnetic field was 10 mili-Tesla. Furrows spacing, length and slope were 0.6 m, 42 m and 0.11 %, respectively. Inflow rate was 0.8 l/s for all the irrigation evens. To determine the net erosion in furrows, water samples were taken from runoff after its start at different time intervals. The net erosion was calculated at each time after determining soil mass in the samples and the net erosion vs. time chart was plotted. The mean erosion was calculated from this chart. The erosion indexes investigated in this study include mean erosion and maximum depth of the furrow cross-section. The results showed that, in all of the water treatments, the net erosion decreases with time in each irrigation., There is also a significant decrease in the mean erosion values in W and M treatments, compared with F treatment, in the second and fourth irrigation events at the 1% (p < 0.01) and 5% (p < 0.05) level, respectively, but there no significant difference between W and M treatments. The effect of irrigation event on the mean erosion was not significant in any treatment. The effect of water treatment on the basic infiltration rate and the maximum depth of furrow cross-section were not significant, but the basic infiltration rate was in most cases higher in M treatment than in F and W treatments in most cases. Also the changes in the maximum depth of furrow cross-section due to subsequent irrigation events were smaller in M and W treatments than in F treatment.
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Applying the logic of chaos in understanding many details of natural phenomena is unexplainable. At this paper, the climate changes of temperature and precipitation over the analysis of chaos in Shiraz geomorphic basin will be discussed.... more
Applying the logic of chaos in understanding many details of natural phenomena is unexplainable. At this paper, the climate changes of temperature and precipitation over the analysis of chaos in Shiraz geomorphic basin will be discussed. Climate changes of a long-term temperature and precipitation were used for 40 years. Then, geomorphic basin physiognomic characteristics were examined at the most superficial layer and the climatic elements were analyzed. The results of this study suggest that climate change of Shirazbasin geomorphic structure is a function of non-linear algebraic curves.
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The aim of this research was to show the better use of internal resources and increased capability of utilizing and optimizing minerals. Also, in this research we tried to present a new way of petrochemical wastewater treatment. In this... more
The aim of this research was to show the better use of internal resources and increased capability of utilizing and optimizing minerals. Also, in this research we tried to present a new way of petrochemical wastewater treatment. In this sample of bentonite, after the production process in microwave through digestion method with Nano Precision, a long chain of detergents was processed and optimized with an organic material (dimethyl octadecyl ammonium chloride). In the beginning of tests, a statistical method was drawn by MINITAB software and Taguchi method. Sampling was made in different times and testing started by a standard method. Among measuring factors, 5 factors of turbidity, TSS, TDS, pH, and COD were evaluated and their changes were investigated in different times based on the amount and type of materials. The effluent COD and BOD are very important. The petrochemical wastewater was measured and it was90ppm(COD) and 3 ppm(BOD). Also, the highestlevel of turbidity for material A (modified bentonite) was 1.2 NTU with 10mg/L of sludge. Considering that the country needed a better wastewater treatment through environment protection, modification of bentonite's structure, and nano application process in this industry along with various available methods, we aimed to take a step towards the development of the country.
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Accurate measurements of hydraulic characteristics of floware needed for design and evaluation of irrigation systems. For measuring flow, flumes are commonly used.is in order to obtain accurate readings for flow measurement, flumes should... more
Accurate measurements of hydraulic characteristics of floware needed for design and evaluation of irrigation systems. For measuring flow, flumes are commonly used.is in order to obtain accurate readings for flow measurement, flumes should not be submerged and the upstream flow should not be affected by the downstream flow. This study investigates a proper way to install trapezoidal flumes that can be applied in many ways to measure in flow and outflow discharge in furrow irrigation systems. During sixty field operations, it was discovered that the flume has to be installed at least four centimeters above the bottom of furrow, in addition to the alignment on each side.This is essential for proper functioning of the flume under the conditions of free flow., Measurements made showed that if flume was held four centimeters above the bottom, the percentage of submergence in different depths of water, had met the standard rate (lower than 70% submergence), and hence the percentage of the error in flow measurement was reduced.In order to ensure the free flow in the trapezoidal flume, the large number of field operations showed that the entrance of the flume, which is used to analyze the inflow, has to be installed at a height of four centimeters or more above the bottom of furrow, with the condition that its entrance borders are strengthened. The exit of the flume should also be firmly fixed on the bottom of furrow in order not to impede the passage of flow, with the condition that beneath the flume the furrow bottom should be made deeper in order to create free flow. These recommendations are important, especially in furrow irrigation systems.
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The objective of this paper was to conduct economic analysis for optimum seasonal irrigation water application by considering seasonal rainfall under water (w w) and land limitation (w l) for rice in Isfahan province. The results showed... more
The objective of this paper was to conduct economic analysis for optimum seasonal irrigation water application by considering seasonal rainfall under water (w w) and land limitation (w l) for rice in Isfahan province. The results showed that the values of w w and w l for different years decreased as the seasonal rainfall increased. The greatest applied water reduction occurred at water limiting condition with 50%–84% for 0–0.25 m seasonal rainfall. The greatest income per unit applied water occurred for water limiting 332 M.J. Amiri et al. condition and it increased from 41%–46% for 0–0.25 m seasonal rainfall, with respect to maximum yield condition. In water limiting condition, with decreased water consumption, the cultivated land increased from 1–5.2 times. In order to attain more net profit, values of w w and w l with a given amount of rainfall decreased with increasing the water price. Reference to this paper should be made as follows: Amiri, M.J., Hamidifar, H., Bahrami, M. and Eslamian, S. (2016) 'Optimisation of deficit-irrigation under variable seasonal rainfall and planning scenarios for rice in a semi-arid region of Iran', Int.
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In this research, the Manning's roughness coefficient under surge and continuous flow was determined based on the volume balance equation in the form of a differential equation that was solved with the six finite difference approximations... more
In this research, the Manning's roughness coefficient under surge and continuous flow was determined based on the volume balance equation in the form of a differential equation that was solved with the six finite difference approximations procedures. Volume balance analysis and Manning's equation for open channel flow were used as governing equations. Six finite difference approximations [forward finite difference (two methods), central finite difference (two methods) and backward finite difference (two methods)] were used as the solution technique. Comparison of the results showed that there is no significant difference between these methods according to average absolute error (AAE) for the 36 datasets. The results of measurements at three different experimental sites indicate that the values of n for continuous flow irrigation were higher than those measured in surge irrigation. The results are satisfied via testing with the field data obtained from different regions and various soil type.
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This paper presents the results of studies performed to determine the effect of water extraction time from the river on the performance of off-stream reservoir. In total, a fixed volume of water is transferred to the reservoir by ten... more
This paper presents the results of studies performed to determine the effect of water extraction time from the river on the performance of off-stream reservoir. In total, a fixed volume of water is transferred to the reservoir by ten scenarios combining different months and optimised release is determined using dynamic programming. Then, indicators evaluating the performance of the reservoir are considered. The results showed that extraction of water in June and lack of water extraction in April led to maximum improvement of volume reliability while water extraction in May and lack of water extraction in April causes maximum improvement in the number of months facing water shortage. Also, water extraction in March and lack of water extraction in May led to maximum improvement of maximum seasonal shortage indicator while lack of water extraction in March improved duration of water shortage indicator.
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The objective of this work is to find atmosphere circulation and sea surface temperature (SST) patterns, which are able to explain the snow precipitation in Central Andes, in Mendoza, and to develop a model for predicting snowfall over... more
The objective of this work is to find atmosphere circulation and sea surface temperature (SST) patterns, which are able to explain the snow precipitation in Central Andes, in Mendoza, and to develop a model for predicting snowfall over the region. For this purpose, a series of regional annual average snowfall (RAS) was used. In this case the series is representative for the Andes Mountain between 30° and 37°S, during 1951-2010. Masiokas et al. (2010] detailed the way this data set was constructed. Years were classified as “dry” if the annual value of snow was below the first quartile and “wet” if it exceeded the third quartile. The “wet” group was made up by 15 years, 9 years were Niño and 4 years were Niña, while the “dry” group was made up by 15 years, only 6 years were Niña and 3 were Niño. For each group, geopotential height anomalies at low levels (1000 Hpa, G1000), middle levels (500 Hpa, G500) and high levels (300 Hpa, G300), zonal wind (U) and meridional (V) at 850hPa and SST fields for different seasons (summer, spring, winter and autumn) were made. The method proposed for predicting snow precipitation in Central Andes (30°-37°S) in Argentina is a regression technique which uses atmosphere and oceanic predictors. The main conclusion is that an intensification (weakening) of the South Pacific anticyclone and the sub-polar low pressure systems and lower (higher) contribution moisture from the north, were observed in dry years (wet). This result let us select some variables and calculate the correlation field between them and RAS in order to define the best predictors. These predictors were used in a multiple regression model. A crossvalidation technique was applied to determine the forecast snow values. Some measures of efficiency were calculated to prove the agreement between predict and observed snow values.
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Flood risk management seeks to reduce flood risk to communities and individuals through identification and analysis of the flood hazard, the vulnerability of communities to these hazards, and the potential resulting consequences.... more
Flood risk management seeks to reduce flood risk to communities and individuals through identification and analysis of the flood hazard, the vulnerability of communities to these hazards, and the potential resulting consequences. Increased frequency of damaging floods in most watersheds of the Iran country and Development Water resources development plan in their, the need for flood risk management and real-time flood control in this watersheds has risen more than ever before. Flood Warning Systems-Decision Support as one of the index flood management, using real-time flood forecasting tools and flood management in the Basin, have a significant role in reducing flood damages. In this regard watershed in Golestan province each year in its huge floods occurred and caused huge losses of life and property is, to establish a monitoring system of flood warning has been selected. In this study, Flood hazard zones all the rivers in Golestan Province were identified in order to extract risk and high-risk areas, and then the situation all the rain-gauge and hydrometric stations visited in the province which is active contains 55 hydrometric stations, 23 rain-gauge stations, 27 rain-gauge stations and 2 synoptic stations. In designing the optimal network of hydrometric station and rain-gauge considering the climatic conditions, geographical and hydrological basin, hydrographical network and operation of surface flow, the status of hydrological data and network status monitoring were proposed 33 rain gauges and 27 hydrometric stations. In telemetry project and River flood warning monitoring system of Golestan province that is a local flood warning system by combining the rain-gauge and hydrometric data stations, 59 original measurement station (Main Station) identified, and have read and telecommunications equipment installed at these stations and exploited, In the original plan in the original measurement stations is intended rain gauges and level meter. The project includes 74 repeater stations, 215 alarm stations and 14 control systems and monitoring stations are considered at the city center of Golestan province and the duty to collect and displaying information of all alarms stations and Main Station. The maximum length of proposed interval of river flood warning system monitoring is for the city Gonbad-e Qabus, Aghala, Bandar Turkmen and Gomishan with a Figure amounts to three billion and forty-four million Rials (8 million $).
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Floods are one of the most common and widely distributed natural risks to life and property. Due to such hazards associated with flooding as disruption of services, health impacts, famine and disease, flood protection must be taken into... more
Floods are one of the most common and widely distributed natural risks to life and property. Due to such hazards associated with flooding as disruption of services, health impacts, famine and disease, flood protection must be taken into account in almost all development projects. Feasibility study of flood and evaluating the sensitive places prone to flood is the main step for controlling and managing the flood and utilizing it. Kaleybar Chay basin, that is located in East Azerbaijan province, is one of the areas which has experienced several floods during the last years and because of mismanagement, it has caused several life and property losses to the residents of this area. In this study, the effective factors which impact on flooding, from physical, hydrological and environmental factors were explored through executing the ANP model. Through the present research, the ETM + image of the Landsat satellite and the ANP model were used considering their abilities in analyzing the criteria and coefficient of their results with their real world. The results of the study showed that in ANP method, 20 percent of the area which is in the north areas of the basin has the high risk from flooding aspect; the results of the study were supplied for recognizing the area with high possibility of flooding in Kaleybar Chay basin and the provided maps will be used in executive organizations (such as governorate, natural resources) for logistics planning and controlling the flood.
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This study is conducted to investigate the regional effects of climate change on Zayandeh-Rud River Basin located in the central part of Iran for the both near and far future scenarios. A combination of various general circulation models... more
This study is conducted to investigate the regional effects of climate change on Zayandeh-Rud River Basin located in the central part of Iran for the both near and far future scenarios. A combination of various general circulation models (GCMs) is used through a weighting approach to generate different climate change patterns including the ideal, medium, and critical patterns. Each of the GCMs has different ability to simulate the baseline climatic parameters in various months and regions of the basin. A new method, namely " modified weighting method based on the actual values "
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Developing methods that can give a suitable prediction of hydrologic events is always interesting for both hydrologists and statisticians, because of its importance in designing hydraulic structures and water resource management. Because... more
Developing methods that can give a suitable prediction of hydrologic events is always interesting for both hydrologists and statisticians, because of its importance in designing hydraulic structures and water resource management. Because of the computer revolution in statistical computation and lack of robustness in at-site frequency analysis, since early 1990 the application of regional frequency analysis based on L-moments has been considered more for flood analysis. In this study, the above-mentioned method has been used for the selection of parent distributions to fit maximum monthly rainfall data of 18 sites in the Zayandehrood basin, Iran, and as a consequence the generalized extreme-value and Pearson type-III distributions have been selected and model parameters have been estimated. The obtained extreme rainfall values can be used for meteorological drought management in the arid zone.
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– Multiplicative seasonal autoregressive integrated moving average models are appropriate for the monthly stream flow of the Zayandehrud River in western Isfahan province, Iran, through the Box and Jenkins time series modeling approach.... more
– Multiplicative seasonal autoregressive integrated moving average models are appropriate for the monthly stream flow of the Zayandehrud River in western Isfahan province, Iran, through the Box and Jenkins time series modeling approach. Among the selected models interpreted from ACF and PACF, seasonal multiplicative ARIMA (1,1,0) × (0,1,1) satisfied all tests and showed the best performance. Seasonal moving average parameter in the model indicates periodicity, and long memory in the streamflow, while a nonseasonal autoregressive parameter indicates the linearity of the monthly streamflow. The model forecasted streamflow for 24 leading months showed the ability of the model to predict and forecast statistical properties of the streamflow.
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In this study, regional climates of Iran were identified based on the properties of the monthly rainfall time series models of 28 main cities of Iran. The autocorrelation (ACF) and partial autocorrelation (PACF) of selected series... more
In this study, regional climates of Iran were identified based on the properties of the monthly rainfall time series models of 28 main cities of Iran. The autocorrelation (ACF) and partial autocorrelation (PACF) of selected series revealed the seasonal behavior of the monthly rainfall. After the parameters of the models were estimated and the residuals of the models analysed to be time independent and the normality was checked using Portmanteau lack of fit and nonparametric tests, the multiplicative ARIMA model was fitted to monthly rainfall time series of the stations. To determine regional climates, a hierarchical cluster analysis was applied on autocorrelation coefficients at different lags and three main climatic groups were found based on the time series models, namely, simple, moderate and complex climates. The results of the time series modeling showed a high variation of the temporal pattern of the monthly rainfall over Iran except for the margins of the Caspian Sea and the Persian Gulf. The study also shows that the correlation between the seasonal autocorrelation coefficient of the rainfall time series and the rainfall coefficient of variation and elevation of the stations is significant while lag-one autocorrelation coefficient does not correlate to rainfall coefficient of variation and the elevation of the stations. Different models also imply the high variation in the spatial rainfall producing mechanism and different stationarity and periodicity characteristics of the rainfall temporal pattern over Iran. A nomenclature of the abbreviation is given at the end of the paper.
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Evapotranspiration (ET) is one of the major components of hydrologic cycle. Accurate estimation of this parameter is essential for studies such as water balance, irrigation system design and management, and water resources management.... more
Evapotranspiration (ET) is one of the major components of hydrologic cycle. Accurate estimation of this parameter is essential for studies such as water balance, irrigation system design and management, and water resources management. Generally we used climate data for calculating evapotranspiration from indirect methods. This study investigates the utility of artificial neural networks (ANNs) for estimation of daily grass reference crop evapotranspiration (ET 0) and compares the performance of ANNs with the conventional methods (Penman, Penman-Monteith, Stanghellini and Fynn) used to estimate ETo in Greenhouse. In the present study, the meteorological variables including air temperature, solar radiation, wind speed and relative humidity were considered daily. The daily outputs from on four physical ET and artificial neural networks have been tested against reference evapotranspiration data computed by the lysimeter to assess the accuracy of each method in estimating grass reference evapotranspiration in greenhouse. The accuracy of ANNs is the best but the accuracy of the Penman equation is the worse for estimating daily evapotranspiration compared with the other equations. In ranking the equations, Stanghellini equation, Penman–Monteith and Fynn, equation ranked in a second, third and forth places, respectively. The results showed the ANNs, Penman and P-M models overestimated ET, while the Fynn and Stanghellini models underestimated ET. The efficiency values of Penman, Fynn, P-M, Stanghellini and ANNs were 0.68, 0.72, 0.86, 0.907 and 0.93 respectively.
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Flood spreading (FS) is one of the suitable methods for flood management and water harvesting that increases the groundwater recharge, makes soil more fertile and increases nutrients in soil. It is also a method for reusing sediment,... more
Flood spreading (FS) is one of the suitable methods for flood management and water harvesting that increases the groundwater recharge, makes soil more fertile and increases nutrients in soil. It is also a method for reusing sediment, which is usually wasted. The purpose of this paper is to investigate the impact of flood spreading on physical and chemical soil properties (soil texture, infiltration rate, pH, EC, Na, P, K, Ca, Mg, Cl, HCO 3 , and SO 4). It is examined that the soil properties change in the flood spreading projection area (FSP). The physico-chemical properties of soil and infiltration rate were measured in different soil depths at both flood spreading and control area. For the 20 cm of top soil, the amount of clay increased after the flood spreading implementation especially in the first and second dikes. Increasing clay was accompanied by decreasing soil infiltration and sand percentage. The mean differences of the clay, sand and infiltration rate between FSP and the control area were statistically significant (P < 0.01). A significant difference was not observed in 20–30 cm of the depth. Soil pH, Mg, HCO 3 , Cl and SO 4 in different soil layers did not show any significant difference between the control and FSP. Soil EC in 0– 20 cm depth of FSP and control area was showed a significant difference (P < 0.05) but no significant differences were found in deeper layers (P < 0.05). K, Na and Ca were remarkably different between 0 and 10 cm depths (P < 0.05) whereas no significant differences were found in deeper layers (P < 0.05). Comparison of the physico-chemical properties and infiltration rates between the dikes in the FSP shows that there are the significant differences between the medians of dike 1 with dikes 2, 3, 4 and 5, but the differences were not observed between dikes 3, 4 and 5. Our results show that the flood spreading operation can be influenced by the area that is under
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Application of large amounts of mineral and organic fertilizers in intensive agricultural regions of Hamadan–Bahar watershed in western Iran contributes to excessive nutrient loads in soils and groundwater bodies. Groundwater supplies... more
Application of large amounts of mineral and organic fertilizers in intensive agricultural regions of Hamadan–Bahar watershed in western Iran contributes to excessive nutrient loads in soils and groundwater bodies. Groundwater supplies approximately 88% of the water consumed in Hamadan. The objective of this study was to investigate the temporal and spatial variability of nitrate leaching in Hamadan–Bahar watershed. We employed the Soil and Water Assessment Tool (SWAT) to model the amount and dynamics of nitrate leaching from a typical crop rotation in this watershed. The SWAT model was calibrated and validated with uncertainty analysis using SUFI-2 (Sequential Uncertainty Fitting, ver. 2) based on measured daily discharge data from 7 hydrometric stations, wheat and potato yield, and measured daily nitrate at the outlet of the watershed. The calibration using crop yield increases the confidence on soil moisture and evapotranspiration. The calibration (R 2 = 0.83, NS = 0.77) and validation (R 2 = 0.70, NS = 0.70) results were quite satisfactory for the outlet of watershed. Spatial variations in nitrate leaching were also found to agree reasonably well with measured nitrate concentrations in groundwater (73% overlap based on a defined criterion). Also, nitrate leaching was found to be more significant under potato (Solanum tuberosum L.) rotation (254–361 kg N ha −1 year −1), representing 30–42% of nitrogen applied to the soil. About 36% of Hamadan–Bahar aquifer has a nitrate leaching rate higher than 100 kg N ha −1 year −1. The presented model and its results have the potential to provide a strong base for considering different scenarios to reduce nitrate leaching and suggest a BMP (best management practice) in Hamadan–Bahar watershed.
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The main limitation of using the results of global circulation models (GCM) is the low spatial accuracy of these models. To use the results of these models one should downscale their results in different areas. Two downscaling models,... more
The main limitation of using the results of global circulation models (GCM) is the low spatial accuracy of these models. To use the results of these models one should downscale their results in different areas. Two downscaling models, Lars-WG and SDSM, were used to downscale the data of daily precipitation and minimum and maximum daily temperature in Kermanshah; and their downscaled results were compared. Due to the fact that the daily precipitation data are not normal and that the data of daily minimum and maximum temperature have autocorrelation, nonparametric tests were used. The investigation of errors in estimating the means was carried out by Wilcoxon rank test and investigation of errors in estimating the variances was carried out by Levene’s test. The investigation of uncertainty in estimating the means and variances of observed and downscaled data is performed by using bootstrap nonparametric test. The results of the used tests indicate the superiority of Lars-WG model than SDSM in downscaling the data of daily precipitation and maximum and minimum daily temperature in Kermanshah (Iran).
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Application of large amounts of mineral and organic fertilizers in intensive agricultural regions of Hamadan–Bahar watershed in western Iran contributes to excessive nutrient loads in soils and groundwater bodies. Groundwater supplies... more
Application of large amounts of mineral and organic fertilizers in intensive agricultural regions of Hamadan–Bahar watershed in western Iran contributes to excessive nutrient loads in soils and groundwater bodies. Groundwater supplies approximately 88% of the water consumed in Hamadan. The objective of this study was to investigate the temporal and spatial variability of nitrate leaching in Hamadan–Bahar watershed. We employed the Soil and Water Assessment Tool (SWAT) to model the amount and dynamics of nitrate leaching from a typical crop rotation in this watershed. The SWAT model was calibrated and validated with uncertainty analysis using SUFI-2 (Sequential Uncertainty Fitting, ver. 2) based on measured daily discharge data from 7 hydrometric stations, wheat and potato yield, and measured daily nitrate at the outlet of the watershed. The calibration using crop yield increases the confidence on soil moisture and evapotranspiration. The calibration (R 2 = 0.83, NS = 0.77) and validation (R 2 = 0.70, NS = 0.70) results were quite satisfactory for the outlet of watershed. Spatial variations in nitrate leaching were also found to agree reasonably well with measured nitrate concentrations in groundwater (73% overlap based on a defined criterion). Also, nitrate leaching was found to be more significant under potato (Solanum tuberosum L.) rotation (254–361 kg N ha −1 year −1), representing 30–42% of nitrogen applied to the soil. About 36% of Hamadan–Bahar aquifer has a nitrate leaching rate higher than 100 kg N ha −1 year −1. The presented model and its results have the potential to provide a strong base for considering different scenarios to reduce nitrate leaching and suggest a BMP (best management practice) in Hamadan–Bahar watershed.
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The increasing demands for environmental protection and sustainable food production require an increase in the use of natural and non-toxic materials for agriculture. In this study, the feasibility of using surfactant-modified zeolite... more
The increasing demands for environmental protection and sustainable food production require an increase in the use of natural and non-toxic materials for agriculture. In this study, the feasibility of using surfactant-modified zeolite (SMZ) in comparison with zeolite clinoptilolite (Cp) application to reduce nitrate leaching and enhance crop growth was investigated. The effects of size (millimeter and nanome-ter) and application rate (20 g kg −1 and 60 g kg −1) of Cp and SMZ on nitrate leaching and crop response were also evaluated. Using soil lysimeters, it was determined that the maximum and mean nitrate concentration in the leachate of SMZ-amended soil were significantly (p < 0.05) lower than those of Cp-amended soil. The amount of NO 3-N leached from SMZ-and Cp-amended lysimeters at the higher application rate (60 g kg −1) was approximately 26% and 22% lower, respectively, than that from the control system. The mean grain yield, grain nitrogen content, stover dry matter, and N uptake were significantly greater in Cp-amended than SMZ-amended lysimeters. There was no significant effect due to the particle size of the two soil amendments. The results implicitly suggest that plants may have a better response if Cp is used as a fertilizer carrier rather than SMZ when applied at a rate of 60 g kg −1 .
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In this study, the ability to remove ammonium (NH 4 +) from aqueous solutions with different Na + concentrations (0.03, 0.1, and 0.3 M) by natural Iranian zeolite in millimeter and nanometer particle sizes was determined and the... more
In this study, the ability to remove ammonium (NH 4 +) from aqueous solutions with different Na + concentrations (0.03, 0.1, and 0.3 M) by natural Iranian zeolite in millimeter and nanometer particle sizes was determined and the equilibrium isotherms were characterized. The effect of ionic strength on NH 4 + release from Iranian zeolite was also evaluated and several kinetic models were tested. It was demonstrated that the initial NH 4 + and Na + concentrations had significant effect on the amount of NH 4 + exchanged. A decrease in Na + concentration resulted in greater amounts of NH 4 + being exchanged and therefore resulted in greater removal efficiency. In addition, three parameter isotherm models (Redlich–Peterson and Langmuir–Freundlich) proved a better fit in terms of the coefficient of determination (R 2) and standard error of estimate (SEE) than two-parameter isotherm models (Langmuir and Freundlich), with the Langmuir model providing a better description of ion-exchange processes than the Freundlich model. NH 4 + release was rapid for the first 60 min, but slowed thereafter, and also displayed a concomitant increase with the ionic strength of the solution. The NH 4 + release data were successfully described by Elovich, power function, and pseudo second-order models, while the best fit was generally found between the experimental data and the Elovich model with R 2 and SEE ranging from 0.866 to 0.958 and 0.043 to 0.194, respectively. Based on the results, it can be suggested that the natural Iranian zeolite is a suitable ion-exchanger for NH 4 + ion removal and consequently has potential as a controlled-release NH 4 + fertilizer.
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1 The need for precipitation data and the importance of its duration in hydrological and climatic phenomena motivate investigators to develop reconstruction methods. Four methods are artificial neural network, normal ratio, inverse... more
1 The need for precipitation data and the importance of its duration in hydrological and climatic phenomena motivate investigators to develop reconstruction methods. Four methods are artificial neural network, normal ratio, inverse distance weighting, and geographical coordinate. These methods are compared in this study using monthly precipitation data of three stations, Dolat-Abad, Kabootar-Abad and Refinery plant around the city of Esfahan, Iran. Mean absolute error and coefficient of correlation of the results are compared to select the most appropriate method. The neural network approach shows the best performance compared with the other methods.
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This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with... more
This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/copyright The main objective of this study is to investigate the effects of climatic parameters variability on evapotranspiration in five climatologically different regions of Iran. The regions include Tehran, Esfahan, Shiraz, Tabriz and Mashhad. Fifty four-year monthly records of temperature, relative humidity, sunshine duration, wind speed, and precipitation depth from 1951 to 2005 comprise the database. Trend and persistence analyses of the data are performed using the Mann–Kendall test, the Cumulative Deviation test, Linear Regression, and the Autocorrelation Coefficient. A sensitivity analysis of meteorological variables in these five regions is carried out using Penman-Monteith formula. In all of the studied regions, sensitivity analysis reveals that, temperature and relative humidity are the most sensitive parameters in Penman-Monteith formula respectively. The results of this study indicate that the effective climatic variables on evapotranspiration are changing, though in each region the variables have significant long-term trends and persistence.
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Soil degradation, most notably caused by salinization and water-logging, creates formidable problems in arid and semi-arid environments. Advancing our knowledge of salt-affected soils is a prerequisite for understanding how salinization... more
Soil degradation, most notably caused by salinization and water-logging, creates formidable problems in arid and semi-arid environments. Advancing our knowledge of salt-affected soils is a prerequisite for understanding how salinization affects environmental concerns, such as soil erosion, nutrient leaching, and lack of vegetation cover. Therefore this study investigated the impact of salt diapirs on soil physicochemical conditions, as well as explored the relationship between halophytic vegetation and soil factors, and described the composition and distribution of plant species in relationship to soil salinity. The study area was divided into three units based on different geomorphologic conditions, slopes and vegetation type. Changes in salinity, soil properties and vegetation were studied. Results showed that the proportion of clay increased while silt and sand decreased with increasing distance from salt diapirs. The presence and kind of ions in all samples consistently indicated high levels of Na, and moderate levels of Mg, Ca, and K. Based on the soil conditions, plant covers were changed to types with more resistance to salinity and water-logging. Typically, this results in a decrease in soil structure stability through degradation of soil aggregates and a variation in the composition of the vegetation toward undesirable species.
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For evaluating the severity of drought in a certain month, two indexes of cumulative precipitation deficit (CPD) and maximum precipitation deficit (MPD) are used such that a regional frequency analysis has been carried out by L-moments.... more
For evaluating the severity of drought in a certain month, two indexes of cumulative precipitation deficit (CPD) and maximum precipitation deficit (MPD) are used such that a regional frequency analysis has been carried out by L-moments. These measures of drought are strongly related to moisture deficits for the vegetation during the growing season. In this paper, 11 synoptic stations in Isfahan province, Iran, with a semiarid environment are used. The stations have a minimum of 10 years of data. The two drought indexes are calculated for all of them in whole months. The WeatherMan tool is used for completing missing data. The Food and Agriculture Organization of the United Nations Penman-Monteith (FAO-PM) method is used for calculating reference evapotranspiration [ET ðFAO-PMÞ ]. According to previous studies , this method is suitable for this region. The Hosking homogeneity test is applied for identifying a homogeneous region. The Hosking goodness-of-fit test is performed to select the best regional distribution. The results show that the region is homogeneous in months 5 to 10, and in the rest of the months, the region becomes homogeneous after using clustering techniques and dividing the region into two smaller regions. Also, the best regional distribution is distinguished generalized logistic in the most months. Therefore, the severity of drought is estimated with various return periods by CPD and MPD. The maximum intensity of drought in the all stations happens in months 6 to 8, which are in late spring to midsummer. The severity of drought in Ardestan, Khoorbiabanak, and Naeen stations is greater than the remaining stations. Using the outcome of this study, the amount of required water can be estimated for agriculture each month, and the amount of water available is effectively managed in this province.
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– A new analytical procedure taking into account the non-uniform outflow profile for hydraulic analysis and design of multiple outlets pipelines is presented. The method is developed based on presenting a new friction head loss... more
– A new analytical procedure taking into account the non-uniform outflow profile for hydraulic analysis and design of multiple outlets pipelines is presented. The method is developed based on presenting a new friction head loss distribution along the lateral. The proposed method simulates pressure and outflow profiles along the trickle or sprinkler irrigation laterals and manifolds, as well as gated pipes. The velocity head change was considered, whereas minor head losses were neglected. The presented technique was compared with the accurate step by step (SBS) method to justify its accuracy for lateral design. The comparison test for various design combinations indicated that the proposed method is sufficiently accurate. The suggested method could be applied in designing irrigation laterals.
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– Area-capacity curves are of the most important physical characteristics of dam reservoirs. These curves are used for reservoir flood routing, reservoir operation, prediction of sediment distribution in reservoirs, etc. In this study,... more
– Area-capacity curves are of the most important physical characteristics of dam reservoirs. These curves are used for reservoir flood routing, reservoir operation, prediction of sediment distribution in reservoirs, etc. In this study, the linear characteristic of a reservoir's depth-capacity data on log-log paper is used and the mathematical equation of the reservoir's capacity-depth curve is obtained based on the shape factor, M. The reservoir's area-depth equation and equation of shape factor are obtained by differentiating the reservoir's capacity-depth equation. The obtained equations are evaluated with the area-capacity data of 8 reservoirs in the United States. The results of this study showed that the obtained equations agree well with the actual data.
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Zayandeh-Rud River Basin is one of the most important basins in central Iran, which has been continually challenged by water stress during the past 60 years. Traditionally, a supply-oriented management scheme has been prescribed as a... more
Zayandeh-Rud River Basin is one of the most important basins in central Iran, which has been continually challenged by water stress during the past 60 years. Traditionally, a supply-oriented management scheme has been prescribed as a reliable solution to water shortage problems in the basin, resulting in a number of water transfer projects that have more than doubled the natural flow of the river. The main objective of this study is to evaluate the reliability of inter-basin water transfer to meet the growing water demand in Zayandeh-Rud River Basin. A system dynamics model is developed to capture the interrelationships between different subsystems of the river basin, namely the hydrologic, socioeconomic, and agricultural subsystems. Results from simulating a range of possible policy options for resolving water shortage problems indicate that water is essentially the development engine of the system. Therefore , supplying more water to the basin without considering the dynamics of the interrelated problems will eventually lead to increased water demand. It is demonstrated that the Zayandeh-Rud River Basin management system has characteristics of the ''Fixes that Backfire'' system archetype, in which inter-basin water transfer is an inadequate water management policy, causing significant unintended side-effects. A comprehensive solution to the problem includes several policy options that simultaneously control the dynamics of the system, minimizing the risk of unintended consequences. In particular, policy makers should consider minimizing agricultural water demand through changing crop patterns as an effective policy solution for the basin's water problems.
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Low flow indices are very important for water resources planning, pollution control, conservation and even recreational use. Determining these indices depends on having access to daily flow discharges. However, in some cases, such data... more
Low flow indices are very important for water resources planning, pollution control, conservation and even recreational use. Determining these indices depends on having access to daily flow discharges. However, in some cases, such data are either insufficient or are not available at all. Hence, in these cases, estimation of the indices requires the use of data in catchments for which streamflow data have been collected. In this paper, it was attempted to estimate the low flow index (7Q10), the 7-day, 10-year lowflow, using principal component regression (PCR) based on physiographic and hydrologic variables. To do so, a two-step procedure was followed. In the first step, ranking method was applied to determine the best fitted distributions on yearly minimum discharges in each gauging station according to distribution suitability for fitting on extremes; the better the distribution fits the data, the higher number is given as ranking. Adding the ranking numbers dedicated to each gauging station, it was revealed that Gamma distribution with two parameters got the highest value and therefore was chosen as the representative distribution in the region. Using Gamma distribution in gauging stations, 7Q10 was estimated in all gauging stations in the basin. In the second step, a PCR was developed due to existence of high-correlated independent variables. To choose the influential components for use in PCR, eigenvector analysis and factor analysis were performed. The results show that the components chosen through the two approaches correspond to each other well. To evaluate the efficiency of the developed PCR in modeling 7Q10, calibration and verification were pursued. The results approve the efficiency of model in predicting 7Q10 in the region under study.
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Estimating Penman–Monteith Reference Evapotranspiration Using Artificial Neural Networks and Genetic Algorithm: A Case Study
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Global warming and its result climate change phenomenon will affect different elements such as water resources in future. One of the effects is on rainfall parameter that its prediction is very difficult and is under impacts of different... more
Global warming and its result climate change phenomenon will affect different elements such as water resources in future. One of the effects is on rainfall parameter that its prediction is very difficult and is under impacts of different elements. In this study, considering Shahrekord synoptic station in Iran, various uncertainty sources in rainfall prediction in future and its effect on dry and wet spells are investigated. In the present research, CCSIRO, CGCM, ECHO-G, HADCM3, ECHAM and PCM AOGCM models and A 1 , A 2 , B 1 and B 2 emission scenarios under effects of three downscaling methods are used. The results indicate significant impact of the various downscaling methods on increasing uncertainty band in rainfall estimation for future periods. The AOGCM models in all of the scenarios except A 2 have accordance. The results of wet and dry spells estimation display a long duration drought at the beginning of upcoming 30-year period and also immediately after that a long duration wet spell.
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This study evaluates climate change impacts on crop production and water productivity of four major crops (wheat, barley, rice, and corn) in Iran's Zayandeh-Rud River Basin. Multi-model ensemble scenarios are used to deal with... more
This study evaluates climate change impacts on crop production and water productivity of four major crops (wheat, barley, rice, and corn) in Iran's Zayandeh-Rud River Basin. Multi-model ensemble scenarios are used to deal with uncertainties in climate change projections for the study period (2015–2044). On average, monthly temperature will increase by 1.1 to 1.5 °C under climate change. Monthly precipitation changes may be positive or negative in different months of the year. Nevertheless, on the annual basis, precipitation will decrease by 11 to 31% with climate change. While warming can potentially shorten the crop growth pe- riod, crop production and water productivity of all crops are expected to decrease due to lower precipitation and higher water requirements under higher temperature. Out of the four studied crops, rice and corn are more vulnerable to climate change due to their high irrigation water demand. So, their continued production can be compromised under climate change. This finding is of particular importance, given the locally high economic and food value of these crops in central Iran.
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The meteorological data such as rainfall and temperatures, covering the period between 1979 and 2008, has been analyzed. The data were simulated using the geographic information systems (GIS) and computer software " MATLAB ". The output... more
The meteorological data such as rainfall and temperatures, covering the period between 1979 and 2008, has been analyzed. The data were simulated using the geographic information systems (GIS) and computer software " MATLAB ". The output results were converted into geographical maps. Three parameters were analyzed: annual mean maximum temperature, annual mean minimum temperature, and mean annual rainfall during the period (1979–2008). The analyzed results were also used to forecast for the period (2009–2018). The results show that no change has occurred in the mean annual rainfall in both northern and eastern part, while it has increased in the central region of Jordan. Although local temperatures fluctuate naturally, but over the past 50 years, the mean local temperature in Jordan has increased rapidly since 1992 by 1.5–2 • C. It is noticed from the data that the change in both maximum and minimum temperatures has clearly begun after 1991, in which this phenomenon may give an indication of changing point in climate of Jordan. As for prediction is concern, the show continuous increase in both maximum and minimum temperatures in the eastern, northern and southern regions of Jordan. The application of GIS in this study was successfully used to analyze the data and to produce 'easy to use' maps to understand the impact of global warming. This application is the first in terms of its applicability in Jordan. The authors believe that the results of this study will be of great help to the decision makers in the field of environment in Jordan.
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In arid and semiarid areas, bimodal and high rainfall leads to infrequent flood that can be extremely damaging. To reduce the impacts of persistent intra-seasonal drought and also to reduce flood damaging in arid and semiarid areas,... more
In arid and semiarid areas, bimodal and high rainfall leads to infrequent flood that can be extremely damaging. To reduce the impacts of persistent intra-seasonal drought and also to reduce flood damaging in arid and semiarid areas, rainwater storage is a prerequisite that keeps water far from evapotranspiration, increases groundwater level and decreases flood hazards modification to exchange between surface water and groundwater through flood spreading, dams, etc. The purpose of this paper is to delineate and explain variations in groundwater recharge and groundwater quality along an ephemeral stream that has been modified by flood spreading. Groundwater samples were collected from 14 deep wells located at different distances from flood spreading projection area (FSPA) in 1 month interval during September 2005 to September 2008. Groundwater quality was followed via Na + , K + , Ca 2+ , Mg 2+ , Cl-, Hco 3-SO 4 2-, Electrical Conductivity (EC) and pH measurements for two time periods between 2005 and 2008. The results show significant impact of flood spreading in groundwater table and groundwater salinity variation. Groundwater table decreased in all study wells, but groundwater drawdown increased by increasing the distance to FSPA (during 4 years study, 11.02 m in the well located at 20 m of FSPA versus 38.88 in the well located at 1,825 m). Also ion concentration increased in all of the wells during the study period, but the increasing ion concentration was significantly less important in FSPA closeness.
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s u m m a r y Probabilistic assessment and prediction of drought provides valuable information for water resources planners and policy makers for developing drought mitigation strategies. In this study an evaluation of drought conditions... more
s u m m a r y Probabilistic assessment and prediction of drought provides valuable information for water resources planners and policy makers for developing drought mitigation strategies. In this study an evaluation of drought conditions in northwest of Iran was performed by means of the Joint Deficit Index (JDI). Monthly precipitation data from 1970 to 2007 based on 50 gauge stations uniformly distributed across the area were used for calculating the JDI. Results show that the JDI provides a comprehensive assessment of droughts and that it is capable of reflecting both emerging and prolonged droughts reported in the data. Furthermore, the method provides a basis for determining the amount of precipitation required to reach normal conditions in future months (1–3 months examined in this study), and the exceedance probability of this precipitation amount. Performance evaluation based on 6 years of independent precipitation data from the region showed Critical Success Index of 0.61 (0.64) for the 1-month (3-month) ahead prediction of the drought conditions. The analysis in this study indicated a good skill in predicting the evolution of drought conditions for the region based on JDI evaluated from monthly precipitation data.
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The effects of hydrogels on the soil water retention characteristic curve (WRC) and on the growth indices of Ligusrum ovalifolium (an ornamental plant dominating in the landscape of central Iran) were studied. Various amounts of hydrogels... more
The effects of hydrogels on the soil water retention characteristic curve (WRC) and on the growth indices of Ligusrum ovalifolium (an ornamental plant dominating in the landscape of central Iran) were studied. Various amounts of hydrogels (Suprab A200) were added to soil samples having different percentage of water proportional to potential evapotranspiration data. A factorial experiment was used for statistical analysis of data. The results of the soil water retention model showed that, hydrogel caused the residual water content and saturated water content to increase. Available water content increases to a maximum of about 2.3 times the control. Application of hydrogels can result in significant reduction in the required irrigation frequency particularly for coarse-textured soils. This is an important issue in arid and semi-arid regions of the world for enhancing the water management of coarse-textured soils.
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Annual evapotranspiration (ET) of mature pistachio tress in saline aquifer of Bahadoran plain in central Iran was first estimated on a distributed basis by running the Surface Energy Balance Algorithm for Land (SEBAL) model through... more
Annual evapotranspiration (ET) of mature pistachio tress in saline aquifer of Bahadoran plain in central Iran was first estimated on a distributed basis by running the Surface Energy Balance Algorithm for Land (SEBAL) model through Landsat 8 satellite data. Finally, the SEBAL estimate of annual water use evaluated by performing water balance analysis over the Bahadoran irrigation district. The water balance ETa estimate was 19% larger than the SEBAL-based ETa due to the uncertainties involved in estimation of Leaching Fraction (LF) parameter. The average LF was estimated to be 28% (with standard deviation of 19%), predominantly higher than the anticipated average leaching requirement of the Bahadoran area (23%). Assuming that SEBAL has provided accurate estimates, 64% of cumulative irrigation depth (792mm of 1242mm) was consumed by the evapotranspiration process of pistachio orchards. Moreover, the average annual released water to the Bahadoran irrigation district seems to be adequate to leach the salts down to the root zone. The latter result depends on the irrigation water salinities as well as per irrigation applied depths which may change from a field to another field and cause to over or under irrigation of pistachio orchards. Such possible under or over irrigations were demonstrated by the fluctuations of leaching fractions (3% to 65%), soil salinities (1.73 to 31.6 dS • m-1) and consequently, the yields (500 to 4200 kg.ha-1). Under such a condition, averages of 0.12kg.m-3 and 0.20 kg.m-3 obtain for water use efficiency and evapotranspiration use efficiency of Bahadoran pistachios, respectively.
Research Interests:
Drought is a normal and recurrent climatic feature that occurs in virtually every climatic zone around the world, causing billions of dollars in loss annually for the farming community. According to the previous studies, drought has the... more
Drought is a normal and recurrent climatic feature that occurs in virtually every climatic zone around the world, causing billions of dollars in loss annually for the farming community. According to the previous studies, drought has the first rank among all natural hazards. This is because, compared to other natural hazards like floods and hurricanes that develop quickly and end in a short time, drought is a creeping phenomenon that accumulates over a period of time across a vast area, and the effect lingers for years even after the end of drought.
For evaluating the severity of drought of a certain year, the maximum cumulative difference between potential evapotranspiration and precipitation is used such that a regional frequency analysis has been carried out by L-moments. This measure of drought is strongly related to moisture deficits for the vegetation during the growing season.
In this paper, 11 synoptic stations in Isfahan province, Iran with a semi-arid environment have been used that those have minimum 10 years data and the mentioned index drought calculated for all of them. FAO Penman-Monteith is used for calculating potential evapotranspiration that according to the previous studies, this method is suitable for this region. Hosking homogeneity test is applied for identifying a homogeneous region with distinguishing and omitting Naeen station as an outlier station. So for the 10 remaining stations, Hosking goodness of fit test is performed. Two Parameter Lognormal (LN2) is selected as the best regional distribution.
The results show that, Ardestan, Shargh Isfahan and Shahreza stations have the most severity drought and
the drought indices for these stations for 100-year return period are 2060.6, 1576.9 and 1550.5 mm, respectively and for 200-year return period are 2112.4, 1616.5 and 1589.5 mm, respectively.
Using the results of this research, required water volume for agriculture can be determined in this province.
For evaluating the severity of drought of a certain year, the maximum cumulative difference between potential evapotranspiration and precipitation is used such that a regional frequency analysis has been carried out by L-moments. This measure of drought is strongly related to moisture deficits for the vegetation during the growing season.
In this paper, 11 synoptic stations in Isfahan province, Iran with a semi-arid environment have been used that those have minimum 10 years data and the mentioned index drought calculated for all of them. FAO Penman-Monteith is used for calculating potential evapotranspiration that according to the previous studies, this method is suitable for this region. Hosking homogeneity test is applied for identifying a homogeneous region with distinguishing and omitting Naeen station as an outlier station. So for the 10 remaining stations, Hosking goodness of fit test is performed. Two Parameter Lognormal (LN2) is selected as the best regional distribution.
The results show that, Ardestan, Shargh Isfahan and Shahreza stations have the most severity drought and
the drought indices for these stations for 100-year return period are 2060.6, 1576.9 and 1550.5 mm, respectively and for 200-year return period are 2112.4, 1616.5 and 1589.5 mm, respectively.
Using the results of this research, required water volume for agriculture can be determined in this province.
The enhanced greenhouse gas effect is expected to cause high temperature increase globally (1–3.5 0C) and this will lead to an increase in precipitation in some regions while other regions will experience a reduced precipitation (±20%).... more
The enhanced greenhouse gas effect is expected to cause high temperature increase globally (1–3.5 0C) and this will lead to an increase in precipitation in some regions while other regions will experience a reduced precipitation (±20%). The impact of expected climate change will affect almost all the sectors of the human endeavor. The purpose of this study is, to detect an existing trend in wind speed and an evaluating effect of climate change on frequency analysis in Iran.
Twenty two stations that their length of records is higher than fifty years have been selected. Five statistical methods are used to detect the trends that are Mann-Kendall, Spearman, Cumulative deviation, Autocorrelation coefficient and Regression analysis. It is revealed clear that eleven stations have an increase or an decrease in trend and the rest has no trend. Climate change leads to being no homogeneity in number of the stations that therefore, it is impossible for using frequency analysis for those stations. One appropriate approach is dividing the stations into two smaller parts, and for each part frequency analysis could be taken if that part is homogenous.
Twenty two stations that their length of records is higher than fifty years have been selected. Five statistical methods are used to detect the trends that are Mann-Kendall, Spearman, Cumulative deviation, Autocorrelation coefficient and Regression analysis. It is revealed clear that eleven stations have an increase or an decrease in trend and the rest has no trend. Climate change leads to being no homogeneity in number of the stations that therefore, it is impossible for using frequency analysis for those stations. One appropriate approach is dividing the stations into two smaller parts, and for each part frequency analysis could be taken if that part is homogenous.
The main objective of this study is to investigate the effects of climatic parameters variability on evapotranspiration in five climatologically different regions of Iran. The regions include Tehran, Esfahan, Shiraz, Tabriz and Mashhad.... more
The main objective of this study is to investigate the effects of climatic parameters variability on evapotranspiration in five climatologically different regions of Iran. The regions include Tehran, Esfahan, Shiraz, Tabriz and Mashhad. Fifty four-year monthly records of temperature, relative humidity, sunshine duration, wind speed, and precipitation depth from 1951 to 2005 comprise the database. Trend and persistence analyses of the data are performed using the Mann–Kendall test, the Cumulative Deviation test, Linear Regression, and the Autocorrelation Coefficient. A sensitivity analysis of meteorological variables in these five regions is carried out using Penman-Monteith formula. In all of studied regions, temperature and relative humidity are the most sensitive parameters in Penman-Monteith formula respectively. The results of this study indicate that the effective climatic variables in evapotranspiration are changing, though in each region the variables have significant long-term trends and persistence.
In recent decades, with continuous droughts, demand for water has been increased and per capita renewable-water has been decreased in many countries which are faced with water limitation and scarcity. Considering the particular hydrologic... more
In recent decades, with continuous droughts, demand for water has been increased and per capita renewable-water has been decreased in many countries which are faced with water limitation and scarcity. Considering the particular hydrologic conditions in Iran, seasonal floods and high intensity of rainfall are important and using artificial recharge projects is unavoidable to augment the water resources. The major problem with recharging projects is the entrance of sediments to the recharging basins. Due to depositing the floating particles, it is necessary to treat and recover permeability of the basins. In this paper, we compare permeability of the basins for artificial recharge in Bagh-e-Sorkh region of Isfahan. To measure the permeability, four double rings have been installed in different places for each basin’s bed and the permeability was measured. Also, some samples were taken from sediments of the region and some of their physical and chemical characteristics, such as soil texture, EC, and nourishing elements, were measured. The results showed that permeability for beds of the pounds highly decreased and had fallen to less than 10 (the first basin) to 25 percent (the fifth basin) of the initial value. Comparing the physical characteristics of sediments from the different pounds indicates that with increasing distance from the system starting point, the sediment depth is decreased and on the contrary the fine sediments are increased. Because of this, the sediment’s thickness was not so much influential in amount and the pace of the final permeability.