ORIGINAL_ARTICLE
Investigation of different interpolation methods for estimation and zoning of precipitation variables in agricultural lands of Aq-Qalla township for rainfed cropping of autumn cereals
Determination of the precipitation spatial variability in agricultural lands is particularly very importance. For this propose, the spatial distribution of precipitation on agricultural lands of Aq-Qalla township evaluated using 18 method-models from deterministic and geostatistic interpolation such as, Inverse Distance Weighted (IDW), Universal Kriging (UK), Ordinary Kriging (OK), Radial Basis Function (RBF) and Local Polynomial Interpolation (LPI). The performance criteria for evaluation were Root Mean Square Error (RMSE) and General Standard Deviation (GSD) with the Cross Validation methods. The results showed that Local Polynomial Interpolation (1 and 2 degree) was the best method to estimate precipitation parameters except spring and June precipitation. Because, it had the highest accuracy and the lowest error for estimating of these parameters. Semivariograms analysis indicated that annual and June precipitation were best fitted to Exponential model, also, autumn, spring and May precipitation by Spherical model. Results of final maps showed that amount of annual, autumn, and June rainfall were lower in north than south regions. Moreover, the results of this research showed that about 65.62 percentage of agricultural lands of Aq-Qalla had suitable level of annual rainfall (300-400 mm). Also, in this area amount autumn rainfall was 101.11 to 166.08 mm. The results indicated that same as temperature requirements, the annual and autumn rainfall requirements of current crops such as wheat and barley are provided in this township. But, amount of spring and June rainfall are non-suitable in this area. Wide area in Aq-Qalla township were under 10 mm rainfall in June.
https://jwsc.gau.ac.ir/article_2688_d95d6ffaaab63db4c8639698345c79b2.pdf
2016-01-21
1
23
Precipitation
Interpolation
geostatistic
Simivirogram
Aq-Qalla
حسین
کاظمی
hossein_k_p@yahoo.com
1
هیات علمی دانشگاه علوم کشاورزی و منابع طبیعی گرگان
LEAD_AUTHOR
خلیل
قربانی
ghorbanikhalil@yahoo.com
2
هیات علمی
AUTHOR
ORIGINAL_ARTICLE
Investigation of the effect of climate change on net irrigation requirement of main crops of Hamadan-Bahar plain using LARS-WG downscaling model
Climate change and its impacts on water recourses is known as one of the most important challenges which human would be faced with it in the future century. In this study, the effect of this phenomenon on net irrigation requirement of main crops of Hamedan- Bahar plain (winter wheat, barley, potato, sugar beet, maize (grain), Peas and onion) was investigated in three next decades. For this purpose, first of all, the capability of LARS-WG5 model was investigated and verified to simulate meteorological variables including minimum and maximum temperature, solar radiation and precipitation at Hamedan synoptic station in the baseline period (1981-2010). In the next step, meteorological variable values were stimulated by HadCM3 model based on A1B, A2 and B1 emission scenarios in the period of 2011-2040. Finally, the net irrigation requirement values of main crops were estimated for base line and three future decades. Based on the simulated results of LARS-WG5 model, the average values of air temperature and precipitation will increase by 0.77, 0.88 and 0.78 0C and 2.1, 5.9 and 10.2 % for A1B, A2 and B1 scenarios, respectively.The results showed that average monthly precipitation will increase in October, December and February for three scenarios and decrease in March, April and May for A2 and B1 scenarios. Also, the total amount of net irrigation requirement of examined crops will increase between 2.6 to 28.2 mm for three future decades compared with baseline period
https://jwsc.gau.ac.ir/article_2689_acff2404171738d19b57372f6514e816.pdf
2016-01-21
25
46
Climate change scenarios
LARS-WG5 model
Net irrigation requirement
Hamadan-bahar plain
Samira
Akhavan
akhavan_samira@yahoo.com
1
گروه مهندسی آب، دانشکده کشاورزی، دانشگاه بوعلی سینا، همدان
LEAD_AUTHOR
محمد
قبائی سوق
ghabaei.m63@gmail.com
2
1دانشجوی دکتری گروه مهندسی آب، دانشگاه بوعلی سینا همدان، ایران
AUTHOR
ابوالفضل
مساعدی
mosaedi@yahoo.com
3
3استاد دانشکده منابع طبیعی و محیط زیست، دانشگاه فردوسی مشهد، ایران
AUTHOR
ORIGINAL_ARTICLE
Effects of organic acids on release of some elements from sepiolite and palygorskite minerals in saline conditions
Limited information is available about the influence of organic acids on dissolution of fibrous clay minerals especially in saline conditions. A laboratory experiment was set up with a completely randomized design and factorial arrangement in three replications to identify the influence of studied parameters on release of magnesium, silicon, and aluminum from sepiolite and palygorskite minerals. Treatments included two types of mineral (sepiolite and palygorskite), two organic acids (citric, oxalic) and a control, and four salinity levels (0, 6, 12 and 24 dS/m). The concentrations of released elements were measured by atomic absorption spectrometry. Results showed that the amount of released elements is highly affected by the type of organic acids, salinity, and type of mineral. Among the organic acids, the amount of Mg and Al released from sepiolite and palygorskite in citric acid treated samples were greater than those from oxalic acid samples. However, oxalic acid was found to be more effective for extraction of Si from the minerals. With increasing salinity, the release of all elements was increased, however; in presence of organic acids the amount of released elements was reduced comparing with non-saline conditions. Moreover, the results illustrated that the ratio of released Si/(Al+Mg) in sepiolite samples was higher than palygoقskite, suggesting that sepiolite is less stable than palygorskite and is much more weathered under the conditions studied.
https://jwsc.gau.ac.ir/article_2690_0b18124cc5248ddeadca34e614755b6c.pdf
2016-01-21
47
65
Weathering
Complex
Aluminum
Magnesium
Silica
Zeinab
Jenagh
z.jenagh@yahoo.com
1
M.Sc. student at Shahid Chamran University of Ahvaz
AUTHOR
Saeid
Hojati
s.hojati@scu.ac.ir
2
استادیار گروه خاکشناسی دانشگاه شهید چمران اهواز
LEAD_AUTHOR
Ahmad
Landi
foahmad@yahoo.ca
3
Associate Professor at Shahid Chamran University of Ahvaz
AUTHOR
ORIGINAL_ARTICLE
Investigation of groundwater level changes trend(Case Study: Urmia plain)
In the world, groundwater resources are counted the second freshwater resources after polar glaciers. Investigating changes in groundwater levels in any region has an important role in planning and sustainable water resources management. In the present research, trend analysis was conducted on groundwater level of 31 piezometeric stations in the monthly and annually scales in the period of 2002-2011 using Mann-Kendall non-parametric test. Trend line slope was estimated by using Sen’s estimator for each time series. Homogeneity of trend was tested using the Van Belle and Hughes method. The results showed that the trend of groundwater level for all stations was negative and the negative trend in 1% probability level was significant for 56 percent of the stations. The investigation of trend line slopes revealed that in average, the groundwater level of Urmia plain has been decreased about 19.9 cm/year. Also, the results of homogeneity test of trend in 5% probability level showed that the trend was non-homogeneous for different months and heterogeneous for various stations.
https://jwsc.gau.ac.ir/article_2691_2a8db3d617e810fa8de8900e82877cea.pdf
2016-01-21
67
84
trend analysis
Sen’ s estimator
groundwater level
Urmia plain
Mann-Kendall
Javad
behmanesh
j.behmanesh@urmia.ac.ir
1
دانشگاه ارومیه- گروه مهندسی آب
LEAD_AUTHOR
رقیه
صمدی
rsamadi191@yahoo.com
2
دانشگاه ارومیه
AUTHOR
حسین
رضایی
h.rezaie@urmia.ac.ir
3
دانشگاه ارومیه
AUTHOR
ORIGINAL_ARTICLE
Water demand management in agriculture and its impact on water resources of Bojnourd basin with WEAP and MODFLOW models
Agricultural and industrial development, degradation of surface water resources, groundwater levels drop are among the major factor causing water scarcity. The integrated management of groundwater and surface waters serves as a solution to cope with such issues. In the present study, using a water resources simulation model WEAP and its adjunction to the groundwater simulation model MODFLOW, consumption for Dashte Bojnourd basin was evaluated. Calibration and validation of both models were undertaken based on 6 years (from 2005-06 to 2010-11) and 2 years (from 2011-12 to 2012-13) respectively. Then different management scenarios, including keeping acreage and cultivation area as constant against increasing number of industries, increasing irrigation efficiency in agriculture were considered combinations of the above scenarios alleviate reduce water demand. Under this scenario, projections for a period of 28 years (from 2013-14 to 2040-41) and its effects on water resources of the basin were studied. The results showed that simultaneous applying multiple water management strategies seems to be better than any of its individual states, reducing water withdrawing on various resources. Reliability of water supply in the whole complex scenario, for urban drinking water, rural, agriculture and industry purposes were estimated to be 100, 100, 60.4 and 71.5 percent. To adopt above scenario alluvial aquifer by drop about 0.47 million cubic meters per year could be the relative balance between aquifers exploitation and recharge but limestone aquifer by drop about 6.02 million cubic meters per year need more management actions to have no problems.
https://jwsc.gau.ac.ir/article_2692_d5e554d7a57b768e3d3a41b7e12aaebd.pdf
2016-01-21
85
101
Water resources management
ground water
simulation
مجید
حجی پور
majeed.hajipour@yahoo.com
1
دانشگاه
AUTHOR
مهدی
ذاکری نیا
a_zakerinia@yahoo.com
2
پردیس کشاوزی دانشگاه گرگان
LEAD_AUTHOR
علی نقی
ضیایی
ziae@yahoo.com
3
فردوسی مشهد
AUTHOR
موسی
حسام
mhesam@yahoo.com
4
دانشگاه گرگان
AUTHOR
ORIGINAL_ARTICLE
Modeling some of the Factors Affecting Rill Erosions Using Fuzzy Inference System
One of the major challenges in planning and management of natural ecosystems such as water and soil resources is lack of understanding the complexities and dynamics of these ecosystems in conventional models. That based on basic idea of fuzzy theory, this limit can be entered in the model. In this study, the fuzzy logic was used to model rill erosion (as a complex natural phenomenon). Various fuzzy models and different methods of defuzzification mechanism were constructed in Mamdany method to determine the optimal model to forecast tracks per unit area of rill erosion in the study area. In all these models, the parameters such as the surface gravel, silt percentage and mutual effects between length and degree of slope (L*S) were considered as input factors of model and cross-section of rills per unit length were considered as the output factors. The results showed that the Gaussian membership function with the defuzzification of smallest maximum is the optimal model for predicting rill erosion in Ahmad-Abad area of Mashhad. The choice of this model, the statistical combination of Ideal point error (IPE), the generalizability of the model was given. According to the results obtained, in the erosion modeling using the softer functions such as Gaussian, will lead to better results than the sharp and simple functions such as trapezoidal and triangular. It is suggested that further research on the use of fuzzy techniques, neural networks and artificial intelligence in the modeling and management of natural resources is done.
https://jwsc.gau.ac.ir/article_2693_4d26b3aa7c299947a83582d4f9649336.pdf
2016-01-21
103
120
Membership function
Fuzzy Logic
Rill erosion
Rangeland. Ahmad-Abad Mashhad
Seyyedeh Motahareh
Hosseini
motahare.hosseini89@gmail.com
1
Former M.Sc student of Rangeland Management, Faculty of Natural Resource and Environment, Ferdowsi University of Mashhad. Mashhad - Iran
AUTHOR
Abolfazl
mosaedi
mosaedi@yahoo.com
2
Professor, Faculty of Natural Resources and Environment, Ferdowsi University of Mashhad
LEAD_AUTHOR
علی
گلکاریان
golkarian@yahoo.com
3
Assistant Professor, Faculty of Natural Resource and Environment, Ferdowsi University of Mashhad
AUTHOR
کمال الدین
ناصری
klnaseri@yahoo.com
4
Assistant Professor, Faculty of Natural Resource and Environment, Ferdowsi University of Mashhad Mashhad, Iran
AUTHOR
ORIGINAL_ARTICLE
Investigation and Detection Effects Of Global Warming On Soil Temperature Trends And Its Estimated Regression Correlation
(Case Study:Kerman)
Climate change detection statistically is a process which could reveal significant changes that are not related natural variations. Thermal energy deposition in soil depths could play an important role in tdetecting climate change. Thus, the aims of this study are to fill the gap in soil temperature data and determination of the effect of global warming on long term soil temperature trends. For this purpose long term annual rainfall and cloudiness, and mean annual air and soil depths temperature (5, 10, 20, 30, 50 and 100 cm) data were collected from Kerman synoptic station. The parametric methods of Pearson and regression techniques, and nonparametric techniques of Spearman and Mann-Kendall were employed to detect temperature trends. The results of these tests indicated that Mann-Kendall could more accurately reveal soil and air temperature trends. The mean annual, spring and summer air temperature trends significantly increased (p ≤ 0.01). The mean annual, summer and autumn soil temperatures also had increasing and significant trends (p ≤ 0.01). These findings also show a significant negative trend in cloudiness and rainfall (p ≤ 0.05). It is concluded that global warming affected air and soil temperatures of Kerman synoptic station.
https://jwsc.gau.ac.ir/article_2694_ae4672717ca91965701d21e77c47afe7.pdf
2016-01-21
121
138
"Non-Parametric and Parametric Tests
Climate Change
Mann-Kendall
Kerman"
sahar
golshan
sahar.golshan@yahoo.com
1
دانشگاه علوم کشاورزی و منابع طبیعی ساری
LEAD_AUTHOR
محمود
رائینی سرجاز
raeini@yahoo.com
2
دانشگاه علوم کشاورزی و منابع طبیعی ساری
AUTHOR
رضا
نوروز ولاشدی
rezanorooz@yahoo.com
3
دانشگاه علوم کشاورزی و منابع طبیعی ساری
AUTHOR
ORIGINAL_ARTICLE
Study on the effect of different land uses on runoff and sediment in Shastkalate Watershed, Golestan Province
Presently, evaluation of soil erosion and sediment yield is one of the challenging issues in watershed management. It is considered to be a concerning issue in the developing countries and thus access to accurate data is essential to measurement of soil erosion and sediment in watersheds for proper designing of soil conservation programs and determine ways to against erosion and reduce sediment. The natural resources degradation and soil erosion are the major problems in Golestan Province. The aim of this study was the investigation of sediment and runoff in experimental plots by using of natural rainfall in the three land uses, forest, planting and disturbed forest in Shastkalate watershed. Nine erosion experimental plots with 2×2 (m) size were installed in all three land uses. The results showed that in 1.7 to 14.4 (mm) precipitation, the amount of sediment were 0.007 to 19.95 (gr) in forest, 0.13 to 11.87 (gr) in planting and 0.26 to 43.94 (gr) in disturbed forest land uses. The amount of runoff varied from 0.23 to 25(l) in forest, 0.1 to 16.1 (l) in planting and 0.27 to 25 (l) in disturbed forest land uses. Results showed that the forest degradation increased erosion and runoff 63.4 and 32% respectively and the amount of erosion and runoff decreased in planting land use 46.6 and 50.7%.
https://jwsc.gau.ac.ir/article_2695_b172ab246b43b8944d9eda5b6f0c59a1.pdf
2016-01-21
139
153
sediment
Shastkalateh
Erosion
Measuring Plots
ریحانه
نوروزی مهیاری
reihaneh.norouzi@gmail.com
1
دانشگاه کشاورزی و منابع طبیعی گرگان
AUTHOR
farshad
kiani
kianifarshad@yahoo.com
2
دانشگاه علوم کشاورزی و منابع طبیعی گرگان
LEAD_AUTHOR
hashem
habashi
habashi@yahoo.com
3
دانشگاه علوم کشاورزی و منبع طبیعی گرگان
AUTHOR
ORIGINAL_ARTICLE
Urban flood management by simulation of surface runoff using SWMM model in Gorgan city, Golestan Province- Iran
A study was done to determine the optimum dimensions of Gorgan city drainage network using model SWMM. In this study, to calibrate the model, four rainfall events, were used and the speed of the corresponding runoffs in the chosen sub basin were recorded. In this study, Nash-Sutcliff, square root of error and bias error were used as model performance indices in the estimating peak discharge and flow volume. The model calibration results showed that the simulated peak discharge and flow volume are in good correspondence with the observed values and the calibration results were used for the optimum values of parameters. To evaluate and test model validation, two rainfall events, were used. The evaluation results were confirmed the efficiency and accuracy of the model, so that the model performance indices were acceptable in both cases. After evaluating model performance, design rainfall with return period was calculated and model with design return period was performed in respect to the optimal parameters and dimensions of the drainage network. Peak discharge passing through the channels was identified based on design rainfall intensities. The adequacy of existing network to carry runoff with design return period was assessed with regard to model results based on presence or absence of added load and flood conditions at the nodes and channels. According to the model results, 40.1, 30.6 and 12.5 percent of drainage network channels possess critical and flood conditions in 2, 5 and 10 return periods respectively.
https://jwsc.gau.ac.ir/article_2696_5bd774c92eb38cd40f168bcacab6cd01.pdf
2016-01-21
155
170
Urban runoff
drainage network
Gorgan
SWMM
saman
badiezadeh
saman.badie84@gmail.com
1
دانشگاه منابع طبیعی گرگان
LEAD_AUTHOR
abdolreza
bahremand
abdolreza.bahremand@yahoo.com
2
-
AUTHOR
amir amad
dehghani
a.dehghani@gau.ac.ir
3
-
AUTHOR
ORIGINAL_ARTICLE
Investigation of temporal changes in groundwater quality of Neishaboor Plain and its possible causes
Water resource limitations in the Neishaboor Plain, together with significant increase in water demand in this area due to the urban, agricultural and industrial development, make it a necessity for researchers to investigate and provide the base information for establishing a sustainable water resource management program. In this study the temporal changes in groundwater quality and the possible causes of these fluctuations were studied. The water quality data used in this investigation included a 9 year (2001-2009) periodically measurements of TDS, total hardness, Na+, Ca2+, Mg2+, Cl- and SO42- concentrations. The results indicated a significant degradation of groundwater quality over the period of the study, as was shown by the increase in concentrations of the quality parameters. The TDS concentration in 77% of the investigated wells raised sharply over the above mentioned period, with an annual mean rate of 19.63 mg/L. In reagard to possible causes of groundwater deterioration, geological formations, the decline in groundwater level, and agricultural activities were realized to be the most important factors. The results showed that with every 0.81m mean annual decline in groundwater level, the TDS concentration increased by a value of 19.63 mg/l. The geological tertiary formations (Miocene) and volcanic rocks were also affecting the spatial quality changes observed in some parts of the Nayshaboor's aquifer.
https://jwsc.gau.ac.ir/article_2697_237b0871463e67756fdbe58a913286ed.pdf
2016-01-21
171
186
Groundwater
Water quality
Neishaboor Plain
Total dissolved solids
Shahnaz
Danesh
sdanesh@ferdowsi.um.ac.ir
1
دانشیار گروه مهندسی عمران دانشکده مهندسی دانشگاه فردوسی مشهد
LEAD_AUTHOR
مصطفی
ابطحی
mohammad.abtahi@yahoo.com
2
دانش آموخته کارشناسی ارشد مهندسی عمران- محیط زیست دانشگاه فردوسی مشهد
AUTHOR
کامران
داوری
kamdav@um.ac.ir
3
دانشیار و عضو ﻫﻴﺌﺖ علمی گروه مهندسی آب دانشکده کشاورزی دانشگاه فردوسی مشهد
AUTHOR
سید علی
قاسمی
sa.ghassemi@stu-mail.um.ac.ir
4
دانشجوی دکتری مهندسی عمران- آب دانشگاه فردوسی مشهد
AUTHOR
ORIGINAL_ARTICLE
Comparison between neural network and M5 tree models
For reconstructing missing evaporation data of khouzestan
Missing meteorological data is one of the problems facing specialists and designers of water recources projects and it,s necessary to reconstruct them. There are different methods for infilling missing data. In this research, performance of tree model and neural network for infiiling missing evaporation data from 4 meteorological stations in khouzestan province, were evaluated. The data were divided into two periods: 4 and 12 years and in each period 5%, 10% and 20% of data were deliberately missed and had been filled by models. In tree model coefficient of determination for 4years period were: 85%, 75% and 85%, and for 12years period were: 90%, 83% and 84% respectively. In neural network model coefficient of determination for 4years period were: 85%, 75% and 85% and for 12years period were: 90%, 82% and 85% respectively. A higher coefficient value for 12 years period showed that models are more accurate to estimate missing data for longer term statistical data. By increasing missing data from 5% to 20%, accuracy of models were diminished. This research also indicated that both models have similar accuracy in the estimation of missing data.
https://jwsc.gau.ac.ir/article_2698_130788682d8d018d77669494fa97df8b.pdf
2016-01-21
187
202
missing data
reconstructing data
evaporatin
tree model
neural network model
Marjan
Vahabi Mashhor
marjan.vahabi@yahoo.com
1
Aboureihan Faculity, Tehran University
AUTHOR
Ali
Rahimikhoob
akhob@ut.ac.ir
2
دانشیار دانشگاه تهران، پردیس ابوریحان
LEAD_AUTHOR
ORIGINAL_ARTICLE
Simulation of Heterogeneous Soil Salinity under Unsteady Condition from a Line Source
Limitation of water resources has led to unusual waters applications and the use of high-efficiency irrigation systems such as drip irrigation in some areas. The mismanagement of water resources has caused increases the accumulation of salts in the soil. Due to the executive limitations of field experiments such as high cost and time-consuming, using of simulator models for studying different management scenarios is recommended. Purpose of this research is evaluation of the salt transport in heterogeneous heavy soil and unsteady conditions with estimating hydraulic and solute transport parameters using inverse solution with the HYDRUS-2D model. Drip irrigation system was applied as a line source and was done with water salinity of 1.279, 2.5 and 5 dS/m. Soil profiles were dug to 40cm depth and networked, 48 hours after irrigation. Sampling from beneath the tape and horizontal distance of 20 cm from the tape was used to determine the salinity of the soil saturation extract. ECe observed values were compared with ECe simulated values using statistical indices i.e. nRMSE and CRM. Simulated soil salinity values were slightly lower than the observed values. Ranges of nRMSE for beneath the tape and the horizontal distance were between 2.79-18.49% and 3.084-20%, respectively. Simulations placed in good to excellent category. Ranges of CRM for beneath the tape were between -0.049 and 0.097 and the horizontal distance were between -0.065 and 0.081. Thus, this model can be used as a suitable tool for the design and management of drip irrigation with saline and brackish water.
https://jwsc.gau.ac.ir/article_2699_bc9927b9dbe7423af9505a635293244e.pdf
2016-01-21
203
216
Accumulation of salt
HYDRUS-2D
Saline water
Firuzeh
Javadzadeh
f_javadzadehsh@yahoo.com
1
MSc Student, University of Guilan
AUTHOR
Mohammadreza
Khaledian
mkh572000@yahoo.com
2
هیات علمی
LEAD_AUTHOR
Maryam
Navabian
navabian@guilan.ac.ir
3
Assistant professor, University of Guilan
AUTHOR
Parisa
Shahinrokhsar
pshahinrokhsar@yahoo.com
4
Researcher at Research center for agriculture and natural resources
AUTHOR
ORIGINAL_ARTICLE
Laboratory investigation of incipient motion of non-cohesive and non-uniform sediment in irrigation and drainage Channels
Sediment control on water distribution and transmission networks has a lot of importance. Sediment input to the channel, is deposited in different parts of transmission and distribution network and reduced capacity of current carrying. And which increases the cost of maintenance and dredging operation will be followed. Cohesive sediment due to dissolving properties and low weight has a little capacity for deposition. There is a major problem caused by non-cohesive sediment which is more possibility for deposition. A lot of research has been recently done to determine the conditions of incipient motion velocity of uniform and non-cohesive sediment in open channels and many Relationships or graphs are presented. But studies on non-cohesive and non-uniform sediments are very little. With regard to the channel sediments are mostly non-uniform, Determination of the flow rate for prevent of sediment deposition can be a effective role in increasing of transmission efficiency and which reduced costs. In this study, incipient motion of non-cohesive and non-uniform sediment was investigated by physical modeling and dimensional analysis. In this study 9 non-cohesive and non-uniform sediment has been tested with different dimensions and uniformity coefficient in 0.0005, 0.001and 0.002 slopes. Results showed that by increasing the slope and particle size parameters, decrease stability parameter and stability parameter, will increase with increasing uniformity coefficient.
https://jwsc.gau.ac.ir/article_2700_574387c2257a3a96871595df092b4422.pdf
2016-01-21
217
229
incipient motion velocity
non-cohesive and non-uniform sediment
channel slope
hossein
khozeymehnezhad
hkhozeymeh@yahoo.com
1
عضوهیات علمی گروه مهندسی آب دانشگاه بیرجند
LEAD_AUTHOR
رسول
مظلوم شهرکی
rasoulshahraki3@yahoo.com
2
دانشجوی کارشناسی ارشد آبیاری و زهکشی دانشگاه بیرجند
AUTHOR
محمد حسین
نجفی مود
mhnajafi2002@yahoo.co.uk
3
عضو هیات علمی گروه مهندسی آب دانشگاه بیرجند
AUTHOR
علی
شهیدی
a47sh@yahoo.com
4
عضو هیات علمی گروه مهندسی آب دانشگاه بیرجند
AUTHOR
ORIGINAL_ARTICLE
Experimental investigation of the effects of block inclinations on the hydraulic jump characteristics in the stilling basin USBR III
Background and objectives: Hydraulic jump is one of the common methods for dissipation of the kinetic energy of the flow in downstream of the hydraulic structures in stilling basins. Length of the stilling basin, depth ratio and the energy loss are some of the important parameters that should be taken into account for designing an economically efficient structure. Historically, Bidone was the pioneer to conduct investigations on the hydraulic jump in 1818.There after characteristics of this phenomenon have been investigated by many researches using cubic, rhombus and trapezoidal baffle blocks with and without curved upstream edges, sinusoidal bed, trapezoidal corrugation, sills and rectangular corrugations. Despite of the comprehensive researches performed during the last two centuries, there are still unknown issues that warrant more research on this subject. The perpose of this research is investigation of the effects of block inclinations on the hydraulic jump characteristics in the stilling basin USBR III.Materials and methods: Experiments were conducted in a flume with glass walls and smooth bed with a rectangular cross section 1m wide, 85 cm deep and 15m long. The model consisted of a head tank, a slice gate with constant opening of 3 cm and a tail gate to obtain various flow depth and a flowmeter to measure the discharge. Part of beginning of flume immediately after the gate of the head tank, was used as stilling basin and baffle blocks and end sill were installed according to the criterion of a type ΙΙΙ USBR stilling basin. In this study, baffle blocks were installed in two cases of diverge and converge position relative to the central axis of the flume and in each position 8 placement angle of 10, 20, 30, 40, 50, 60, 70 and 80 degrees were considered for blocks. For each flow discharge, the tailgate was adjusted to establish a non-submerged hydraulic jump so that toe of the jump was formed at the beginning of the flume under upstream gate, then the length of jump, initial and secondary flow depth were measured and burst photos were taken from profile of the jump. Froude numbers and discharges ranged from 4.44 to 8.56 and 39 to 81.7 l/s respectively. In total, 180 tests were carried out for classic, USBRΙΙΙ and diverge and converge position jumps.Results: In diverge position, increase in the placement angle of blocks up to 30° on convergent position caused significant decrease in jump length and further increase in placement angle resulted in separation of jump front from walls of flume and inclination to the central axis of flume and in turn increase of jump length. Also in diverge position, for all placement angles of blocks increase in jump lengths were observed.Conclusion: The results showed that, increase in the placement angle of blocks up to 30° on convergent position caused 40 percent decrease in jump length and 10 percent decrease in depth ratio and also increase in relative energy loss to 75 percent. It is believed that the main reason of decreasing the jump length was raising the rate of secondary flows due to inclination of blocks in angle of 30 degrees.
https://jwsc.gau.ac.ir/article_2701_dcc4a002dfd7ed9f117b7e858cb1b004.pdf
2016-01-21
231
242
Hydraulic jump
stilling basin USBR III
Baffle blocks
placement angle
zahra
eshkou
z.eshkou@gmail.com
1
Phd Candidate of Shahrood University of Technology
LEAD_AUTHOR
ahmad
ahmadi
a.ahmadi@shahroodut.ac.ir
2
عضو هیات علمی و رییس دانشکده مهندسی عمران
AUTHOR
amirahmad
dehghani
amirahmad.dehghani@gmail.com
3
عضو هیات علمی و معاون آموزشی دانشکده آب
AUTHOR
ORIGINAL_ARTICLE
The assessment hazard desertification using desertification indicator system for Mediterranean Europe (DIS4ME). (case study : Atrak watershed in Golestan province)
Desertification is a phenomenon that has been impacted by the natural, social and financial factors and vice versa. The first step in desertification and desertification combat plan should be based on the identification and studying phenomena which are responsible for the changes in areas and induce desertification.Also, The intensification of desert conditions is considered as a trend which leads to biological reduction of ecosystems and desertification of environmental condition. In this research, by using GIS 8 indices are selected and evaluated in Atrak Watershed of Golestan province: soil, vegetation, climate, management, Runoff, Land use and composite Inicators. The model of DIS4ME is applied in this research. Each of factors is estimated one by one, and for each of them, data was collected.The result showed that 5.5% of study area was found to be in critica (c1), 25% in critica (c2) and about 69% in critica (c3) class of desertification. Also soil, vegetation cover and climate criteria with a geometric average of 1.67, 1.62 and 1.58 show high class desertification.
https://jwsc.gau.ac.ir/article_2702_474a2ecda379b2cbff9b4a29f670ce8e.pdf
2016-01-21
243
251
Desertification map
Geographical Information System
DIS4ME model desertification
Desertification Index
Atrak Sofla Watershed
مریم
بخشی
bakhshi.maryam6@gmail.com
1
STUDENT
LEAD_AUTHOR
choghi bairam
komaki
bkomaki@gmail.com
2
assistant professor
AUTHOR
majid
ownegh
mownegh@yahoo.com
3
professor
AUTHOR
ORIGINAL_ARTICLE
Trend Analysis the Number of Dusty Days in The Sistan and Baluchistan Province (IRAN) Using Non-Parametric Statistics
In this study, some available dusty day's data were analyzed to identify the trend of dusty day by synoptic stations in the Sistan and Baluchistan Province. It was identified that all selected weather stations have the complete, long-enoughrecorded data. To provide a preliminary view of a subjected climatology, the average number of days with dust yearly and monthly data have been examined. It was determined that inside of the study area, the occurrence of days with dust are not homogeneous and such phenomena increases from the south to the north. To review the trend of occurrence of dusty day's non-parametric statistical methods of Mann-Kendall was accordingly introduced to the data. Primary results showed that this method could be adapted for signifying of the existing trend types. Result showed that all stations have positive trend in monthly and yearly periods. But in warm months (May, June, July and August) positive trend are larger than other months.
https://jwsc.gau.ac.ir/article_2703_4ddfb3b954d4e2d802105e39629d447a.pdf
2016-01-21
253
260
Dusty days
Mann-Kendall method
Sistan and Baluchistan Province
علیرضا
شهریاری
nimaaryan2002@yahoo.com
1
عضو هیات علمی دانشگاه زابل
LEAD_AUTHOR
ORIGINAL_ARTICLE
Derivation and investigation of regional flood analysis models as a function of return period (Case study: Ardabil province)
Improving techniques of regional flood frequency estimation at ungauged sites is one of the foremost goals of contemporary hydrology. The evaluation of the frequency of flood events in ungauged catchments are usually approached by building suitable statistical relationships (models) between flood statistics and basins characteristics. In this study, regional flood frequency was curried out between flood as a dependent factor and physical characteristics as independent factors using inverse method in the catchments of Ardabil province. To yield a single model, return period was taken into account as independent factor. Study area consists 9 gauging stations in the central regions that seven gauging stations for calibration and 2 gauging stations for validation were used. Four types of models including Area, Area-slope, Area-slope-channels length models and Fuller model were studied. Results showed that lowest correlation between estimated parameters was concerned to Area model. Therefore estimated parameters of this model was unique and contact high confidence with compare to others models. Fuller model did not show suitable estimation of flood. Area, Area-slope, Area-slope-channels length models estimated flood with good accuracy for return period less than 50 years. Accuracy of mentioned models decreased with increasing return period. Area model with RMSE equal to 25.30 and 23.51 (m3/s) showed lowest accuracy and Area-slope-channels model with RMSE equal to 9.51 and 6.32(m3/s) highest accuracy for estimation of flood in the validation gauging stations.
https://jwsc.gau.ac.ir/article_2704_69b652eaf4e68457b8aecf501d332f2f.pdf
2016-01-21
261
268
Regional flood analysis
Inverse method
Regression
Uncertainty
Ardabil catchments
علی
رسول زاده
rasoulzadeh@uma.ac.ir
1
هیات علمی دانشگاه محقق اردبیلی
LEAD_AUTHOR
Elnaz
Azartaj
elnaz_1369_azartaj@yahoo.com
2
M.S. student of Watershed Management, College of Agriculture, University of Mohaghegh Ardabili, Ardabil, Iran
AUTHOR
Parisa
Farzi
farzi_pari@yahoo.com
3
M.S. student of Watershed Management, College of Natural resources, Torbat Heidariye University, Iran
AUTHOR