ORIGINAL_ARTICLE
Uncertainty Analysis a single event distributed rainfall-runoff model with using two different Markov Chain Monte Carlo methods
So far flood forecasting and simulation in hydrologic literature suffer from lack of explicit recognition of forcing and parameter and model structural error. However since any model is a simplification of reality there remains a great deal of uncertainty even after the calibration of model parameters. Often parameters in hydrologic models cannot be measured directly and can only be inferred by a calibration process. This work addresses the application and comparison of two parameter uncertainty methods and their effects on the prediction of streamflow in Abolabbas watershed (290 km2) located in Khuzestan Province. Two Markov Chain Monte Carlo methods, Shuffled Complex Evolution Metropolis (SCEM UA) and DiffeRential Evolution Adaptive Metropolis (DREAM) were used in this study to quantify parameter uncertainty in AFFDEF implemented in FORTRAN language programming, a single event distributed rainfall runoff model. Respectively, four and two historical floods with hourly time step for calibration and validation periods were selected. More than 45000 Simulation runs with 15 chains were done to indicate convergence to a stationary posterior distribution. For example, results showed that p-factor and d-factor values for event 31/1/1993 changed from 0.92 and 2.25 in SCEM-UA approach and reached to 0.96 and 1.56 in DREAM approach respectively. Finally posterior parameters distributions were created with samples from last 20 percent of chains. All of these posterior distributions properly become smaller than initial upper and lower bounds.
https://jwsc.gau.ac.ir/article_2122_df7752cc7db76256c65f6314adec9f94.pdf
2014-12-22
1
26
Uncertainty Analysis
Markov Chain Monte Carlo
Single event distributed rainfall-runoff model
Mohsen
Pourreza Bilondi
mohsen.pourreza@gmail.com
1
دانشگاه بیرجند گروه مهندسی آب دانشجوی سابق دکتری دانشگاه شهید چمران اهواز
LEAD_AUTHOR
Ali Mohammad
Akhoond ALi
mohsen9010@yahoo.com
2
استاد دانشکده مهندسی علوم آب، دانشگاه شهید چمران اهواز
AUTHOR
Bijan
Ghahraman
bijan_ghahraman@yahoo.com
3
استاد گروه مهندسی آب دانشگاه فردوسی مشهد
AUTHOR
Abdolrasoul
Telvari
telvari@gmail.com
4
دانشیار گروه عمران دانشگاه آزاد واحد اهواز
AUTHOR
ORIGINAL_ARTICLE
Comaprison of Soil Erosion by 137CS and RUSLE-3D for Loess Deposits North-East of Iran (Study Area: Aghemam Catchment)
Significant reduction in performance of watersheds in Iran due to the high volume erosion indicate the need for increased monitoring and follow-up of this destructive phenomenon. In this way, using new methods and knowledge is important. Around the world many erosion model as137Cs and RUSLE-3D model are used for soil erosion estimation. In this paper, soil erosion was estimated in Aghemam catchment by 137Cs and RUSLE-3D methods due to importance and high sensitivity of loess deposits in this area. Due to the lack of observed data in this area and because of high accuracy of 137Cs method in estimating soil erosion, performance of RUSLE-3D model was determined by Comparing data collected from 137Cs with RUSLE-3D model. The erosion rate was estimated 10.78 ton/ha/yr by using 137Cs method, while this amount was 2.61 ton/ha/yr by RUSLE-3D model. In this study the erosion rate obtained by two methods were compared in the slope classes of 0-15º and in > 15º , also in cultivated and uncultivated land uses. Finally these two methods have low correlation and RUSLE-3D model is not recommended in this area.
https://jwsc.gau.ac.ir/article_2123_4219c8c43528c4a8862956eeccb85563.pdf
2014-12-22
27
47
Soil erosion
loess deposition
137Cs
RUSLE-3D
Aghemam catchment
حسین
سیدعلیپور
h.seyedalipour@gmail.com
1
دانشگاه علوم کشاورزی و منابع طبیعی گرگان
AUTHOR
سادات
فیض نیا
sfeiz@ut.ac.ir
2
گروه احیا مناطق خشک و کوهستانی دانشگاه تهران
AUTHOR
حسن
احمدی
ahmadi@ut.ac.ir
3
گروه احیا مناطق خشک و کوهستانی دانشگاه تهران
AUTHOR
محمدرضا
زارع
m_r_zare@yahoo.com
4
استادیار گروه فیزیک دانشگاه اصفهان
AUTHOR
Mohsen
Hosseinalizadeh
alizadeh_m2001@yahoo.com
5
عضو هیات علمی گروه آبخیزداری و مدیریت مناطق بیابانی
LEAD_AUTHOR
ORIGINAL_ARTICLE
Economical Optimization of Diverging Stilling Basins with Rectangular and Trapezoidal Sections
Stilling basins are one of the most common structures for energy dissipation of flow with high velocities downstream Hydraulic Structures. Among these basins, diverging basins with rectangular and trapezoidal Sections is an alternative choice of classical basin because of better hydraulic performance in order of sequent depth, and relative energy loss and also no need to transition structure. The aim of this research is to investigate the effect of diverging walls of stilling basins on the structural costs in comparison with classical basins using results of physical model of hydraulic jump in diverging rectangular and trapezoidal basins with side slopes 1:0.5, 1:1 and 1:1.5, diverging angels 3-9 degree and The Froude numbers of 2.6 and 9. The results showed that in case of diverging basins with rectangular sections, increase in divergence angle from 4-9 degree, causes increase in hydraulic jump efficiency about 10-29 percent and decrease in structural costs about 4-20 percent. In addition to, the results of optimization model that was solved with Genetic Algorithm showed that in trapezoidal sections, for the Froude numbers lower than 4, diverging angel 3 and side slope 1:0.5 has the best performance. Comparison of results showed that with increase side slope and divergence angle in the trapezoidal sections, the structural cost of basins increases because of increasing in the jumps length.
https://jwsc.gau.ac.ir/article_2124_4d0c6dfff8c05916c554557dbdd448fc.pdf
2014-12-22
49
70
Diverging Stilling Basin
jump efficiency
structural costs
Genetic Algorithm
mahdi
esmaeili
esmaeili.varaki@yahoo.com
1
عضو هیات علمی گروه مهندسی آب دانشگاه گیلان، سازه های هیدرولیکی/مهندسی رودخانه
LEAD_AUTHOR
فرزانه
صاحبی
sahebi..farzaneh@yahoo.com
2
دانشجوی کارشناسی ارشد دانشگاه تبریز
AUTHOR
مریم
نوابیان
ma_navabian@yahoo.com
3
هیات علمی گروه مهندسی آب دانشگاه گیلان
AUTHOR
زهرا
امیری
amiri_zahra@guilan.ac.ir
4
هیات علمی گروه توسعه روستایی دانشکده علوم کشاورزی دانشگاه گیلان
AUTHOR
ORIGINAL_ARTICLE
The effects of chemical and organic manures on stabilization of Lead and Cadmium in polluted soils
AbstractThe application of phosphate fertilizers and organic matter have been known as a stabilization (immobilization) technique to reduce solubility of heavy metals in contaminated soils. In this respect, the application of phosphate fertilizers and municipal solid waste compost on mobility of Pb and Cd and uptake of those metals studied by plant in a polluted loamy soil. The green house study was performed in complete randomized design with treatments of ammonium phosphate (75mg P2O5/kg), triple superphosphate (75mg P2O5/kg) and municipal solid waste compost (2%) compared with control in three replicates. The results showed that the availability of lead was significantly reduced with increased phosphate fertilizers in comparison with control. The applied various P fertilizers decreased uptake of Cd and Pb significantly whereas compost did not affect significantly by aerial part of Gladiola. Also the applied P fertilizers decreased soluble and exchangeable Cd and Pb fractions, compared with control, but compost had not affected. It is therefore concluded that the application of P fertilizers within agricultural fields may be prevented entering heavy metals into the food chain.
https://jwsc.gau.ac.ir/article_2125_b1f227403c17808031fb191251843c7e.pdf
2014-12-22
71
92
Keyword: Phosphate fertilizers
compost
Lead
Cadmium
Gladiola
Ghasem
Rahimi
ghasemr@gmail.com
1
Bou-Ali Sina University
LEAD_AUTHOR
Haftrani
Dodangeh
h.dodangeh62@yahoo.com
2
دانشجوی کارشناسی ارشد
AUTHOR
Safar
Marofi
smarofi@yahoo.com
3
عضو هیات علمی
AUTHOR
Mansour
Gholami
man.gholami@gmail.com
4
عضو هیات علمی
AUTHOR
ORIGINAL_ARTICLE
Effect of discharge ratio and stream angle on flow pattern at rectangular junction channels with fluent model
Open channel confluences occur in many natural and artificial waterways. Several hydraulic and geometric parameters such as discharge ratio, Froude number, junction angle, channel bed slope and bed roughness can affect flow pattern at channel junctions. Study of flow pattern in rigid boundary channels can help prediction of morphological changes in fluvial natural channels. In this research, the effect of discharge ratios and side channel junction angles on flow pattern for angles 30০, 45০, 60০ and 90০ using Fluent CFD model have been studied. Results showed that in =90০ junction angle, dimensions of separation zone disappear near bed (z*=0.05) for discharge ratio of Q*=0.917. Also in 45০,the dimensions of separation zone near bed are negligible. The maximum dimensions of separation zone are take place near water surface (z*=0.95) for discharge ratio of Q*=0.917 and 90০ degree junction channel. Increase in discharge ratio will lead to form uniform a flow downstream of junction area and so decrease in separation zone dimension. Also Maximum and minimum values (16% and 4%) of surface water level occur in highest and lowest discharge ratios of 0.83 and 0.917 respectively.
https://jwsc.gau.ac.ir/article_2126_6b281eda9ca5bde1f3b3c3f3c8738207.pdf
2014-12-22
93
114
Junction channel
Separation zone
Junction angle
Discharge ratio
Fluent model
saeed
gohari
saeedgohari@yahoo.com
1
دانشگاه بوعلی سینا – دانشکده کشاورزی– گروه مهندسی آب
LEAD_AUTHOR
mohammad
amraei
m.amraei2010@yahoo.com
2
دانشجوی کارشناسی ارشد رشته آبیاری و زه کشی
AUTHOR
علی
فلک دین
falakdinali@yahoo.com
3
دانشجوی کارشناسی ارشد رشته آبیاری و زه کشی
AUTHOR
ORIGINAL_ARTICLE
Numerical Modeling of Scour Pattern Downstream of Combined Flow over Weirs and Under the Gates by Flow3D
By combining weirs and gates the problems of sedimentation and floating materials upstream the weir and gate structure can be resolved. In combined structures a new hydraulic condition is created which is differing from hydraulic condition in weir and gate only structures. Due to jet flow passing through or under structure, the scour hole is formed downstream of structures that’s may endanger the stability of the structure. So determination of scour hole characteristics is attracted by researchers. The object of this study is numerical modeling of scour pattern downstream of combined flow over weir and under the gate by Flow3D software. For modeling the turbulence, RNG k- , k- and LES were used. Flow3D is a high accurate model in computational fluid dynamics for simulation of problem with complex geometry on wide limits of fluid flows in open channel hydraulic. By applying VOF method, a series of simulation scour pattern downstream of weir - gate structure were performed and results were compared by some experimental data. The results show that Flow3D with LES turbulent model can be used with high accuracy (with R2=0.96, RMSE=0.0117) to simulation of scour pattern and water surface profile in weir - gate structure.
https://jwsc.gau.ac.ir/article_2127_d076b33417c48cc91b6fdf6abb2a96dd.pdf
2014-12-22
115
133
combined flow
scour pattern
weir - gate
Numerical modeling
Flow3D
mohamad
kaheh
kahemohamad@gmail.com
1
دانشجو
AUTHOR
امیر احمد
دهقانی
amirahmad.dehghani@gmail.com
2
استاد گروه
LEAD_AUTHOR
مهدی
کاهه
mehdi.kaheh.17@gmail.com
3
استاد
AUTHOR
عبدالرضا
ظهیری
zahiri_reza@yahoo.com
4
عضو هیات علمی
AUTHOR
ORIGINAL_ARTICLE
Comparison and Calibration of Nine Mass Transfer- Based Reference Crop Evapotranspiration Methods at Urmia Lake Basin
AbstractThe aim of this study is to compare and calibrate nine different mass transfer-based reference crop evapotranspiration ( ) estimation methods in monthly time scale at Urmia Lake basin. The selected methods were Meyer (M), Dalton (D), Rohwer (R), Penman (P), Brockamp and Wenner (BW), Mahringer (Ma), Trabert (T), WMO and Albrecht (A) methods. For this purpose the information of ten synoptic weather stations in the period 1986-2010 were used. Results of the mentioned methods compared with the output of the FAO-56 Penman-Monteith (PM56) method. Calibration of methods performed in the case of every station and months in the mentioned time period. Performance of methods evaluated using the R2, RMSE, MBE, MAE and PE statistics. Results showed that before calibration larger biases existed for the selected methods comparing the PM56. Calibration of methods considerably improved their performances. The M method was recognized as a best method after calibration at the study watershed. The median of R2 value of this method was 0.8945. In the mentioned method (after calibration) the median of the RMSE, MBE, MAE and PE was found to be equal to 21.8, -8.7, 17.3 and 21.5 mm per month. The Dalton method selected as the second best one. Methods namely, R, P, BW, Ma, T, WMO and A ordered as the third till ninth rank methods.Key Word: Evapotranspiration, Mass Transfer- Based methods, Penman-Monteith, Urmia Lake Basin
https://jwsc.gau.ac.ir/article_2128_0b9bff76990ca669fc73e5617cfcbadb.pdf
2014-12-22
135
153
Key Word: Basin
Evapotranspiration
Mass Transfer
Penman-Monteith
Urmia Lake
امید
بابامیری
obabamiri@yahoo.com
1
دانشگاه تبریز
LEAD_AUTHOR
یعقوب
دین پژوه
dinpashoh@yahoo.com
2
دانشیار دانشکده کشاورزی دانشگاه تبریز( گروه مهندسی آب)
AUTHOR
ORIGINAL_ARTICLE
An investigation of Rainfall and Supplementary Irrigation Productivity in some Wheat Cultivars
In water scarcity areas, improving water productivity is one of the most effective options to increase production. This is achieved by improving both crop and irrigation management. An experiment was laid out in strip plots with a randomized block design consisting of six rotations, six cultivars of wheat and two irrigation regimes (rain-fed and supplementary irrigation) treatments with three replications during the four years (2007-2011). Results show that varieties, climate conditions and irrigation has affected on wheat production. In contrast, different rotations of wheat have no significant effect on wheat yield. In the years that a significant portion of the total crop water requirement was provided by rainfall about 75 percent, yield potential of irrigated wheat was low and also there was no significant difference between wheat yields in irrigated and rainfed conditions. So that, irrigated wheat yield from 2007 to 2011 was obtained about 69, 6, 21 and 88 percent higher than the rainfed wheat, respectively. Rainfall use efficiency of wheat in four consecutive years was obtained 1.67, 1.79, 1.31 and 1.1 and irrigation water use efficiency was obtained 0.75, 0.36, 0.81 and 2.2 Kg/m3, respectively. Highest wheat yield and also highest rainfall/irrigation use efficiency is related to the cultivars N-80-19 and N-81-18. Since supplemental irrigation in most cases has not led to increased water productivity, in the Golestan province condition, wheat irrigation should be done in the critical period of wheat growth and saved water could be allocated to water scarcity areas or for the summer crops.
https://jwsc.gau.ac.ir/article_2129_b53712e52f0538c3d73801f75cd08c57.pdf
2014-12-22
155
173
Water use efficiency
Supplemental irrigation
Crop Rotation
Wheat
Alireza
kiani
akiani71@yahoo.com
1
مرکز تحقیقات کشاورزی گرگان
LEAD_AUTHOR
Abbass
Nourinia
nourinia@gmail.com
2
عضو هیئت علمی
AUTHOR
ORIGINAL_ARTICLE
Analysis of Storm-wise Sedimentgraphs and Rating Loops in Galazchai Watershed, West-Azarbaijan, Iran
Studying sedimentgraph is an important tool in analyzing sediment behavior leading to success in watershed management projects. The present study was conducted in the Galaz Watershed in West-Azarbaijan Province, Iran, with an area of some 103 km2 to analyze sedimentgraph and rating loops of 13 observed storm events from 25 October 2011 to 25 November 2012. The water and sediment data were recorded with 1 h interval and corresponding sedimentgraphs and rating loops were developed. The results showed that the clockwise type-rating loops were occurred in 7 storm events due to early peak incidence of the sedimentgraphs (0.5 to 4 h) with respect to peaks of hydrographs. However, other types of sediment rating loops were recognized for other storm events. The results indicated that the clockwise type of sediment rating loops were due to prompt contribution of steep slopes adjacent to the watershed outlet. Although, figure-eight and complex types of sediment rating loops could be attributed to sediment sources of the cropland areas with high sediment availability during autumn cultivation in the watershed upstream and confluence of rising and falling limbs of the hydrograph. The study also showed that 4 observed storm events had consequent storm events. So that, the total weights of total suspended sediment in the first events were respectively 1.5, 3.9, 10.2 and 4.6 times higher than the second events. The results further revealed that each individual storm events had two distinguished peaks, which proved the contribution of available sediments from agricultural lands located in upland areas.
https://jwsc.gau.ac.ir/article_2130_ad3fb3bec1b903e06d65707c143eb072.pdf
2014-12-22
175
191
Land use
Sediment availability
Sediment-Discharge Relationship
Sediment yield
Temporal variations of suspended sediment
Raoof
Mostafazadeh
raoofmostafazadeh@uma.ac.ir
1
Tarbiat Modares University
AUTHOR
Seyed Hamidreza
Sadeghi
sadeghi@modares.ac.ir
2
Tarbiat Modares University
LEAD_AUTHOR
Amir
Sadoddin
amir.sadoddin@gmail.com
3
Gorgan University of Agricultural Sciences and Natural Resources
AUTHOR
ORIGINAL_ARTICLE
Performance Assessment of Water distribution in Tajan Irrigation and Drainage Network
Delivery of adequate water in suitable time is one of the main objectives of water distribution systems in the irrigation network. Tajan irrigation network is one of the important networks in the Northern of Iran which irrigates a major part of Sari plains since 1376. In this study, the performance of a main canal of Tajan irrigation network was evaluated by using efficiency, adequacy, equity and stability indicators. To measure Indicators, firstly the Q-H relationship was obtained for each sub-channel and inlet as well as outlet sections of the main canal using field measurements. By using automated water level measuring devices and Q-H relationships, the exact amount of flow delivered to each water intake and the flow discharges in the main channel were then measured in two irrigation periods at one minute time intervals. Water requirement of each water intake was calculated using the NETWAT computer program. Using water requirement computed by software, performance indicators were calculated for main canal and water intakes. Overall, the performance of the canal is low. Traditional distribution of water in irrigation network despite its mechanization, lack of precise knowledge of Mirab about exact water required for each water intake and poor maintenance of control and intake structures prevent the proper management of water distribution. Based on the results, removing the barriers and introduce strategies for managing and operation irrigation network can increase the performance of the irrigation network.
https://jwsc.gau.ac.ir/article_2131_fc3137d4dbcd61fc960abb78b20b120a.pdf
2014-12-22
193
208
performance indicators
network management
water delivery and distribution
ساسان
مددی
sasan.madadi@yahoo.com
1
دانش آموخته-دانشگاه علوم کشاورزی و منابع طبیعی ساری
AUTHOR
علی رضا
عمادی
emadia355@yahoo.com
2
علوم کشاورزی و منابع طبیعی ساری
LEAD_AUTHOR
علی
شاهنظری
aliponh@yahoo.com
3
عضو هیات علمی-دانشگاه علوم کشاورزی و منابع طبیعی ساری
AUTHOR
ORIGINAL_ARTICLE
Effect of placement of horizontal drain in irrigation channel on the slope stability in Neka plain channel
One of the sensitive and important problems during construction projects, such as choosing the spot in concrete or earth dams, open channel, choosing the highway, main road or sub road and etc, is studying the pore water pressure through the embankment and supplying their stability. One of the instability and failure reasons of slope is pore water pressure. This phenomenon, especially in moist region and in sites with saturated clay soils, is clear. Water pheratic level changes cause changing in pore water pressure in embankment which cause decrease in safety factor. In this paper and for a case study, effectiveness of horizontal drain in safety factor is done with PLAXIS-V8.2 in three conditions (maximum level, rapid drawdown and slow drawdown) is evaluated which safety factors obtained 1.6, 1.73 and 2.8 respectively. With location of horizontal drain, maximum increase for safety factor occurred when drain located in the roof which for rapid drawdown, slow drawdown and maximum water level equal to 1.62, 2.03 and 2.8 respectively. The results indicate that horizontal drains role in slope stability is impressive and pore water pressure is a main factor in this regard. With change location of the horizontal drain, pore water pressure calculated by use two PLAXIS and PLAXFLOW software. Minimum pore water pressure equal to -63.58 and -63.60 respectively, obtained.
https://jwsc.gau.ac.ir/article_2132_76f0671013f65336a25460b91be65659.pdf
2015-03-15
209
223
Pore Pressure
Safety Factor
Plaxis Software
Drawdown
mohammad
hamidi gharetapeh
hamidi_m36@yahoo.com
1
Sari university
LEAD_AUTHOR
سید حسن
گلمایی
h.golmaei@sanru.ac.ir
2
دانشگاه علوم کشاورزی و منابع طبیعی ساری
AUTHOR
mir khalegh
ahmadi
m.ahmadi@sanru.ac.ir
3
دانشگاه علوم کشاورزی و منابع طبیعی ساری
AUTHOR
ORIGINAL_ARTICLE
Evaluation of drinking water quality of Ardabil plain aquifer by cokriging and fuzzy logic
In arid and semi arid regions like Iran, exploitation and allocation of groundwater resources have a great importance. In this study, the methods of cokriging and fuzzy logic have been used for qualitative classification of groundwater in Ardabil plain for drinking purpose. Thus, qualitative data related to the TDS, TH, pH, Ca2+, Mg2+, Cl-, Na+ and SO42- parameters of seventy-six wells were used. This study included two stages that in the first one distribution of these parameters by cokriging interpolation method (for each point of the plain) has been derived. Then in the second stage, these interpolated data have been used as fuzzy logic inputs. The qualitative spatial distribution map of plain was generate with identifying membership functions for each of parameters in three classes “Desirable”, “Acceptable” and “Not-acceptable” and with fuzzy attitudinal to drinking water quality standard. In general, to classify groundwater quality, 105 rules were specified. According to obtained results, 3.5, 68 and 28.5 percents of Ardabil plain area have Desirable, Acceptable and Not-acceptable quality respectively, for dinking. This spatial distribution map can help a lot for exploitation of groundwater resources and offers a good insight of groundwater qualitative trend in this study area.
https://jwsc.gau.ac.ir/article_2133_61f2ad71cf60c03db0583da70a76aa20.pdf
2014-12-22
225
240
Groundwater
Quality classification
Interpolation
Cokriging
Fuzzy Logic
Mehdi
Kord
kord@tabrizu.ac.ir
1
استادیار دانشگاه کردستان
LEAD_AUTHOR
Asghar
Asghari-moghaddam
moghaddam@tabrizu.ac.ir
2
Professor University of Tabriz
AUTHOR
ORIGINAL_ARTICLE
3D numerical simulation of scouring around pier within
a long contraction with applying numerical model SSIIM
Today Scouring is one of the important issues in the river engineering science. Determining the relationship between factors influencing the depth and the maximum depth of scouring as well as finding the governing function are some of the concerns of hydraulic engineering in which it is tried to find the numerical relationship between scouring depth as a dependent variable and the effective parameters on this phenomenon. Hence, a powerful numerical model is required for converting the complicated relationships governing on the phenomenon in to simple and solvable equations. In this research, the SSIM numerical model could properly simulate scouring at a pier within a long contraction. The results indicated that scouring at a pier within a long contraction can be minimized by increasing in channel opening ratio, increasing the size of sediment particles, choosing piers with properly shaped cross sections, and distancing piers from the contraction's beginning and lateral boundaries
https://jwsc.gau.ac.ir/article_2134_1be4428824774b65407b927555f8946a.pdf
2014-12-22
241
256
scouring
Contraction
numerical simulation
Pier
numerical model SSIIM
mehdi
meftah
meftah_20@yahoo.com
1
دانشگاه علوم کشاورزی و منابع طبیعی گرگان
LEAD_AUTHOR
Fatemeh
Hajebi
hajebi_fatemeh@yahoo.com
2
مدرس/ دانشگاه جامع علمی کاربردی
AUTHOR
ORIGINAL_ARTICLE
Spatial and seasonal pattern in climate change, temperatures across Iran
Spatial and seasonal pattern in climate change, temperatures across IranAbstractThe present study is mainly concerned with the changing trend of temperature of Iran based on NCEP data from atmospheric general circulation model under A1B scenario. The date were divided into two periods 1961-1990 and 1991-2050 and for each periods, modified Mann-Kendall test have been used together with the Sen’s Slope Estimator for the determination of seasonal trend and slope magnitude, then the resulting values for each grid point of atmospheric general circulation model network were classified The result showed that in the first period, trend were detected only in summer and winter seasons in some area but in the second period, trend were detected in all of season and area. Also slope of train line were greatest in summer and smallest in winter and this gradient in west and southwest of Iran greater than other area.Keywords: Sen’s Slope Estimator, Air Temperature, Trend, General Circulation Model, Modified Mann-Kendall.
https://jwsc.gau.ac.ir/article_2135_bde7deacbd6cacb3d00c3d26cf3be041.pdf
2014-12-22
257
270
Sen’s Slope Estimator
Air Temperature
Trend
General Circulation Model
Modified Mann-Kendall
khalil
ghorbani
ghorbani.khalil@yahoo.com
1
دانشگاه
LEAD_AUTHOR
ORIGINAL_ARTICLE
Assessment of evaluation indicators in sprinkler irrigation using non-dimensional infiltrated depth indexes
The uniformity of water distribution by sprinkler irrigation is an important design factor that affects water use efficiency and leaching of solutes. The irrigation application uniformity is affected by changes in wind speed and its direction, sprinkler characteristics and variations in operating pressure. The purpose of this paper is to present modified equations for evaluating the pressurized irrigation systems based on non-dimensional infiltrated depths. The equations have been obtained by four data groups including the average of the measured depth values in any quarter. Coefficient of uniformity, CU, distribution uniformity, DU, application efficiency, Ea and deep percolation ratio, DPR are selected indicators to evaluate the sprinkler irrigation system. The suggested method is compared to the traditional approach for assessment the evaluation indicators, also collected data from a wheel-move system in Chaharmahal & Bakhtiari province. The relation between CU and DU was analyzed for 3 scenarios of the average depth. The results show that the application efficiency was estimated 12% less than previous equations because of using four average values. Coefficient of uniformity and distribution uniformity in wheel-move system was calculated 0.78 and 0.66, respectively.
https://jwsc.gau.ac.ir/article_2165_e518e779269f69996b9b99e852f21217.pdf
2014-12-22
271
283
uniformity
Sprinkler Irrigation
Application Efficiency
Deep percolation
رضا
لاله زاری
lalehzari@hotmail.com
1
دانشجوی دکترای دانشگاه شهید چمران اهواز
LEAD_AUTHOR
فریده
انصاری
laari@hotmail.com
2
کارشناسی ارشد آبیاری و زهکشی
AUTHOR
سعید
برومندنسب
rezalalehzari@yahoo.com
3
هیات علمی
AUTHOR
مظاهر
امینی
mazaher@yahoo.com
4
کارمند
AUTHOR
ORIGINAL_ARTICLE
Comparison of methods for estimating shear stress distribution in width of open channels
The shear stress is used in many of sediment transport equations, turbulence models, identification of stable river reaches, river bed and bank erosion, and river morphology studies. Furthermore, shear stress distribution along river bed and banks is essential for forecasting changes of river geometry. Unfortunately, in spite of great importance of shear stress, direct measurement of this parameter in the rivers is very difficult, especially during flood, hence researchers have proposed indirect methods to calculate the shear stress. In this study, three methods have been used for predicting lateral distribution of boundary shear stress in open channels, and their results were compared with experimental data in the cases of simple and compound channels. The results show that the quasi–two dimensional model of Shiono and Knight (SKM) by considering the secondary flow effect is more accurate than the merged perpendicular method (MPM) and vertical depth method (VDM). The average relative errors of the SKM, MPM and VDM for prediction of the shear stress in laboratory simple and compound channels are calculated as 8, 14 and 18 percent, respectively.
https://jwsc.gau.ac.ir/article_2166_1d8f1d88d1047324b500e39e5cba5803.pdf
2014-12-22
285
295
Boundary shear stress
Quasi–two dimensional mathematical model
Compound channels
secondary flow
Fatemeh
houshmandi
f_houshmandi@yahoo.com
1
دانشجوی دانشگاه منابع طبیعی گرگان
LEAD_AUTHOR
عبدالرضا
ظهیری
zahiri_reza@yahoo.com
2
استادیار گروه مهندسی آب، دانشگاه علوم کشاورزی و منابع طبیعی گرگان
AUTHOR
امیر احمد
دهقانی
amirahmad.dehghani@gmail.com
3
استادیار گروه مهندسی آب، دانشگاه علوم کشاورزی و منابع طبیعی گرگان
AUTHOR
مهدی
مفتاح هلقی
meftah_20@yahoo.com
4
دانشیار گروه مهندسی آب، دانشگاه علوم کشاورزی و منابع طبیعی گرگان
AUTHOR
ORIGINAL_ARTICLE
Evaluation of Hydrus-2D for soil water infiltration by using laboratory measurements in the weighing lysimeter
Although solutions of transient water flow can be obtained by numerical modeling, their application may be limited in part as root water uptake is generally considered to be one-dimensional only. The objective of this study was to evaluation accuracy of two-dimensional root water uptake model by Hydrus-2D in the Lysimeter. The root water uptake model was incorporated into a two-dimensional flow model, and parameters of governing equation were optimized based on minimizing the residuals between measured and simulated water content data. Water content was measured at different points and layers. To calibrate the flow, a genetic algorithm was used. With the optimized parameters of model, simulated and measured water contents during the 30 days period were in excellent agreement. Based on results, R2 values generally ranging between 0.92 and 0.94 and a root mean squared error (RMSE) of 0.0236 m3m-3. In this Paper effect of soil hydraulic properties on Hydrus simulation was evaluated by several predict of neural network. Finally, Result illustrated that Hydrus-2D is extremely flexible in simulation of soil water content pattern.
https://jwsc.gau.ac.ir/article_2167_be2a1b42711b5bfd8b20c86dd03c3942.pdf
2014-12-22
297
306
Hydrus-2D software
Soil water content
Weighing Lysimeter
Soil water infiltration
سینا
بشارت
s.besharat@urmia.ac.ir
1
دانشگاه ارومیه
AUTHOR
Javad
behmanesh
j.behmanesh@urmia.ac.ir
2
دانشگاه ارومیه- گروه مهندسی آب
LEAD_AUTHOR
حسین
رضایی
h.rezaie@urmia.ac.ir
3
دانشگاه ارومیه
AUTHOR
رضا
دلیر حسن نیا
delearhasannia@yahoo.com
4
دانشگاه تبریز
AUTHOR