List of Articles منحنی سنجه

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  1 - Investigating the Effect of Land Use Changes on the Distribution of Dam Reservoir Sediment (Case Study: Lasak Dam) Using the HEC-RAS Model
  Saeed Rashedi Seyed Abbas Hosseini Sara Nazif Bagher Ghermezcheshmeh
  10.30495/wsrcj.2023.73193.11376
  Introduction: In the last few decades, due to the growth of industries, drastic changes have occurred in the climate of the planet, and its average temperature has increased significantly. Land use changes and climate have had a great impact on discharge and sediment pr More

  Introduction: In the last few decades, due to the growth of industries, drastic changes have occurred in the climate of the planet, and its average temperature has increased significantly. Land use changes and climate have had a great impact on discharge and sediment production in watershed. The increase in the production of sediments has many harmful environmental and constructional effects; among these effects we can mention the reduction of the useful depth of the dam and consequently the reduction of the life of the dam. The purpose of this study is to investigate the process of sedimentation along the Mubarakabad River (Emamzadeh Ebrahim watershed) and the effect of time on the increase in the sedimentation depth of the Lasak dam reservoir located in Guilan province using the HEC-RAS model in different states for the time range of 1997 to 2071. Methods: Mubarakabad River is one of the main branches of Pasikhan River, which is the most important river supplying water to Anzali wetland. This watershed has various uses, including forest, degraded pasture, medium pasture and good quality pasture, residential, paddy field, etc. To carry out this study, land use changes in the years 1997, 2007, 2020, 2040 and 2071 were used. In order to measure the runoff, sediment and flow rate in the coming years (2022 and 2071) with the help of the LARS-WG statistical model in two scenarios (RCP 4.5 and RCP 8.5) and SWAT tool was investigated. To implement the HEC-RAS model, three models of surface reduction were used: Borland and Miller's method, Moody's surface reduction method and surface increase method. The input variables of the model are loaded in three sections: topographic map, discharge information, discharge-sediment, and sediment grading. The model was calibrated using discharge and sediment data during the study period. In this study, changes in sedimentation along the Mubarakabad River from upstream to the construction site of Lasak Dam were investigated. Also, the sedimentation depth of the dam reservoir was investigated in different years using the HEC-RAS model. Results: The simulation results of this study showed that with passing of time, the percentage of residential areas will increase significantly and the area of pastures located in the southern part of the basin will decrease. Currently, in this basin, the total area of 1.87 km2 has been allocated to the residential sector, which includes several villages. While in 2071, this amount will reach 21.45 km2. Also, pastures with dense coverage in this basin in 1997 were equal to 99.65 km2, and in 2071 this amount will decrease to 4.82 km2. The results of this study showed that from the source to the construction site of the dam, sediment deposition has increased due to the reduction of the slope, and the largest amount of sediments have accumulated in the reservoir of the dam. It was also observed that with passing time, the depth of sediments behind the dam reservoir has increased significantly, which reduces the efficiency of the dam. The results of this study showed that there is an increasing trend in the sedimentation depth of the reservoir, so that its maximum value was obtained in 2071, equivalent to 39.1 meters from the height of the dam intake. The results of this study show that in the years 2071 and 2040, 2.02 and 1.92 million tons of sediment will settle in the Lasak dam reservoir, respectively. Conclusion: According to the results obtained from the HEC-RAS model simulation in the Emamzadeh Ebrahim watershed, it can be seen that if detailed and executive planning is not done in this area, land use change will occur severely. This change of uses causes the increase of soil erosion and production of sediment in the watershed, in other words, this change of uses can be considered as an alarm for the destruction of Anzali Wetland. In general, due to the conditions of the watershed and its high erosion upstream, the life of the Lasak dam will not be long, and its construction will reduce the water rights of the Anzali wetland and lead this international wetland to complete destruction at a faster rate.  Manuscript profile
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  2 - Evaluation of gamma test, cluster analysis, discriminant function analysis and andrews curves methods to separate homogeneous watersheds for regional analysis of suspended sediment
  Hossein Kheirfam Mehdi Vafakhah
  Sediment yield resulting from soil erosion in the watersheds is the major limitation in achieving the sustainable development and major threat to ecosystems. Therefore estimation of output sediment from watersheds is very important. Extent of watershed and deficiency of More

  Sediment yield resulting from soil erosion in the watersheds is the major limitation in achieving the sustainable development and major threat to ecosystems. Therefore estimation of output sediment from watersheds is very important. Extent of watershed and deficiency of sediment measuring stations have caused us to use different indirect methods to estimate sediment, such as the use of models provided in similar watersheds. In this study 42 sediment measuring stations in south and southeast of the Caspian Sea with over 20 year period were chosen. By relating suspended sediment load to stream discharge in the times of flood , daily suspended sediment was estimated by using the daily discharge and the average of annual sediment was calculated. By using the Gamma Test, 13 factors affecting sediment yield were reduced to 5 main factors and by using cluster analysis, discriminate function analysis and andrews curves, study stations were put in homogeneous groups. For each homogeneous group obtained from any one of the mentioned homogenization methods and by using five main factors selected, regression models were developed to estimate the average of annual suspended sediment. Error rates and accuracy of prepared models by using statistical indices of RE, RBIAS and RRMSE were calculated according to observed data. Results indicated that all three homogenous techniques had better results than those of the general model and Andrews Curves with 38.12 and 45.91% RE, 53.16 and 33.11% RRMSE and -0.01 and 0.01 RBIAS in calibration and validation stages, respectively and had better performance than those of two methods i.e. Cluster Analysis and Discriminate Function Analysis for homogenizing of south and southeaster Caspian Sea watersheds based on sediment yield. Also peak discharge (Qp) has the most impact on the average of annual suspended sediment changes. Manuscript profile
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  3 - Evaluation of Suspended Sediment Load by Sediment Rating Curves and Comparing with Artificial Neural Network and Regression Methods (Case study: Babolrud River Mazandaran Province)
  Alireza Mardookhpour Hosein jamasbi Omid Alipour
  10.22034/jest.2018.22430.3152
  Background and Objective: In this research the object is prediction of suspended sediment load by and artificial neural network (ANN), Sediment Rating Curves (SRC) and regression methodfor BabolrudRiver in Mazandaran province. Method: The inputs conclude discharge and t More

  Background and Objective: In this research the object is prediction of suspended sediment load by and artificial neural network (ANN), Sediment Rating Curves (SRC) and regression methodfor BabolrudRiver in Mazandaran province. Method: The inputs conclude discharge and the output is sediments concentration in time series. The input and output of river have positive procedure for (1979-2013) and 75% of data utilized for training and 25% for tests. For training the network, data that recognize issue conditions were selected and some data for testing, Findings: The results show the concentration of sediment suspended load derived artificial neural network and is close together and regression coefficient is 92.8%, while regression coefficient is 83% for sediment rating curves and 90% for statistical method respectively. Discussion and Conclusion: In conclusion, artificial neural network (ANN) has more workability and flexibility for prediction of suspended sediment load to sediment rating curves and statistical methods. Manuscript profile
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  4 - Investigation of the accuracy of multilayer perceptron network and radial base function in estimating river sediment (Case study: Zayandehrud)
  Ramtin Sobhkhiz Alireza Mardookhpour
  10.22034/jest.2021.56444.5208
  Background and Objective: Estimating the amount of sediment by the river is one of the topics that has been considered by many researchers since the past. Reduction of the dam reservoir capacity because of sediments has different effects on different sections and causes More

  Background and Objective: Estimating the amount of sediment by the river is one of the topics that has been considered by many researchers since the past. Reduction of the dam reservoir capacity because of sediments has different effects on different sections and causes adverse effects on the water rights that were initially agreed upon, which will impose several economic and specific consequences. This study aims to model and estimate the amount of suspended sediment using existing experimental equations and new methods called black box. Material and Methodology: The discharge (volumetric flow rate) related to Zayandehrud River in Eskandari station, one of the hydrological measuring stations, has been used to estimate the amount of sediment. For this purpose, water discharge and sediment rate are used as input and output, respectively. Findings: According to the obtained results, it is concluded that the RBF network has better performance due to less error in the test stage, but the MLP network seems to have a better performance considering other parameters and the error in the TRAIN stage. Discussion and Conclusion: Finally, after modeling by using neural networks, the Einstein relationship, and the sediment measurement curve, it is inferred that neural networks are more accurate to estimate the amount of sediment. Manuscript profile
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  5 - برآورد بار رسوب معلق رودخانه ها با استفاده از روش های هیدرولوژیکی مختلف (مطالعه موردی: رودخانه سیاهرود مازندران)
  رضا صالحی طالشی عسکری تشکری نجم الدین واصلی
  در یک حوزه آبخیز، رسوب در اثر فرسایش و تحت تاثیر عواملی مانند تخریب مراتع، تغییر کاربری، کشاورزی غیر اصولی و سایر موارد بوجود می­آید که مشکلاتی نظیر رسوب­گذاری در مخازن و کاهش حجم مفید آن ها، کاهش کیفیت آب از لحاظ مصارف کشاورزی، کاهش بازدهی سازه­های هیدرولیک More

  در یک حوزه آبخیز، رسوب در اثر فرسایش و تحت تاثیر عواملی مانند تخریب مراتع، تغییر کاربری، کشاورزی غیر اصولی و سایر موارد بوجود می­آید که مشکلاتی نظیر رسوب­گذاری در مخازن و کاهش حجم مفید آن ها، کاهش کیفیت آب از لحاظ مصارف کشاورزی، کاهش بازدهی سازه­های هیدرولیکی و نیز برخی مشکلات زیست محیطی را سبب می شود. تغییرات بار رسوبی در یک رودخانه پارامتر مهمی در مدیریت پروژه­های آبی و شاخصی جهت نشان دادن وضعیت فرسایش خاک و شرایط اکولوژیکی حوزه می‌باشد. تخمین بار رسوبی رودخانه در محدوده وسیعی از مسائل، نظیر طراحی مخازن سدها، انتقال رسوب رودخانه­ها، تعیین تاثیرات مدیریت آبخیزها و حفاظت محیط زیست کاربرد دارد. این تحقیق در مورد رودخانه سیاهرود استان مازندران انجام شده است که منبع اصلی تامین کننده آب بخش وسیعی از مزارع کشاورزی منطقه محسوب می شود. در این پژوهش با بررسی کارآیی منحنی‌های سنجه رسوب و انتخاب مناسب‌ترین منحنی، سعی شده است تخمین نسبتأ قابل اطمینانی از میزان بار معلق رسوبی رودخانه ارائه گردد. بدین منظور از آمار دبی روزانه جریان و آمار متناظر دبی جریان- دبی رسوب معلق که به صورت همزمان در برخی از روزهای سال اندازه‌گیری شده اند، طی یک دوره آماری 13 ساله ( از سال آبی 78-1377 تا سال آبی 90-1389 ) از تنها ایستگاه هیدرومتری واقع در مسیر اصلی رودخانه استفاده شد. انتخاب مناسب‌ترین منحنی با استفاده از شاخص‌های آماری میانگین مربعات خطا و ضریب تبیین انجام گردیده و با ترسیم منحنی های سنجه یک خطی، چند خطی و حد وسط دسته ها برای رودخانه‌ی مورد مطالعه، منحنی سنجه حد وسط دسته‌ها با ضریب تبیین 93/0 بعنوان منحنی سنجه رسوب مناسب انتخاب گردید و سپس با استفاده از روش‌های مختلف گذر حجمی، میزان بار معلق رودخانه برآورد شد. این روش‌ها شامل تلفیق منحنی سنجه حد وسط دسته‌ها با: دبی متوسط روزانه، دبی متوسط ماهانه، منحنی تداوم جریان و روش تلفیق دبی متوسط ماهانه و روزانه می‌باشد. در نهایت نتایج حاصل از این 4 روش باهم مقایسه گردید و روش منحنی سنجه حد وسط دسته ها و تلفیق آن با دبی متوسط روزانه، بعنوان مدل بهینه در برآورد بار رسوب معلق رودخانه سیاهرود مازندران انتخاب شد. ضمنا میزان بار رسوب معلق در محل ایستگاه هیدرومتری به روش انتخابی، 55855 تن در سال برآورد شد. Manuscript profile
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  6 - Investigation of sediment rating curves error for estimating flood events sediment yield in Gharachay river
  J. Varvani Sh. Khalighi
  Estimating flood events sediment yield and its temporal variation are of the main and basic issues in watershed management strategies. On the other and there are little investigations about sediment yield behavior of the flood events and applicability of the sediment ra More

  Estimating flood events sediment yield and its temporal variation are of the main and basic issues in watershed management strategies. On the other and there are little investigations about sediment yield behavior of the flood events and applicability of the sediment rating curves to estimate sediment load of flood events. In this study in order to investigate bias and errors of the sediment rating curves in estimating sediment load of the flood events, the estimated values of 10 types of rating curves compared by the observed values of some hourly monitored flood events in the Gharachay River of  Markazi provinces. By considering accuracy and precision indexes the results shows that in all of treated sediment rating curves underestimated (40-80%) flood hydrograph sediment yield in this case the FAO’s method has relatively closer estimates to the observed data and despite of suitable applicability of the MVUE method in estimating annual  sediment yield  it could not prove to be applicable in the flood events cases. Manuscript profile