Mohammad Ebrahim Banihabib; Bahman Vaziri
Abstract
Since most of water and soil researches require artificial rainfall simulation, thus rainfall simulators are applied instruments in this field of study. For this reason, various rain simulators have been designed, built and employed in researches till now. Even though all rainfall simulators provide ...
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Since most of water and soil researches require artificial rainfall simulation, thus rainfall simulators are applied instruments in this field of study. For this reason, various rain simulators have been designed, built and employed in researches till now. Even though all rainfall simulators provide good simulation for rainfall intensity, but simulation of varied rainfall by them are expensive and complicated, and field study cannot conducted easily by them. Thus, in this research, in order to simulate rainfall similar to natural rain and applicable for field tests, it is aimed to design and build a simple and affordable rainfall simulator using flow cascades reservoirs (tanks) routing. The result of calibration the simulator shows it has error less than 5%. Moreover simulation of observed hyetograph of Niyavaran station showed error of 6.1%. The simulator can simulate hyetographs with 3 hours duration and 30 millimeter per hour intensity. Consequently, the proposed instrument and its numerical model can be applied for simulating artificial rainfall hyetograph in rainfall erosion and infiltration field research tests.
Mohammad Rostami Khalaj; Ali Salajeghe
Abstract
Rainfall-runoff modeling is on of runoff estimation techniques and an appropriate tool for studying hydrological processes, water resources evaluation and watershed management. But the complexity and the non-linear nature of rainfall-runoff process and not being known factors affecting it and generally ...
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Rainfall-runoff modeling is on of runoff estimation techniques and an appropriate tool for studying hydrological processes, water resources evaluation and watershed management. But the complexity and the non-linear nature of rainfall-runoff process and not being known factors affecting it and generally on discharge at watershed outlet, modeling has become more difficult. Therefore, using the methods that have additionally dynamic, development capability, conceptual structure and user friendly is essential. Therefore, in this study for rainfall-runoff modeling were used system dynamics methods in the Kardeh dam basin of Mashhad. The proposed model includes 6 reservoir including snow storage, canopy storage, impervious storage, surface soil storage, subsurface storage and groundwater storage. The input data required includes average daily precipitation and temperature. To calibrate the model daily discharge data from basin outlet in the period from 1998 to 2008 and for evaluation the discharge from 2009 to 2012 were used. The results of sensitivity analysis showed temperature parameters are more sensitive and have considerable impact on discharge and peak flow. Also the results indicate that the simulated stream flow pattern is quite similar to that observed and Nash-Sutcliffe coefficient obtained in the evaluation period between 0.57-0.67 which represents that the system dynamics methods is high ability to rainfall-runoff modeling.
Aiding Kornejady; Hamid Reza Pourghasemi
Abstract
The current study is aimed to map landslide susceptibility in the Chehel-Chai Basin is located in the Golestan Province. To this end, two data mining models namely support vector machine and boosted regression tree were employed due to their robust computational algorithm. Landslide inventories were ...
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The current study is aimed to map landslide susceptibility in the Chehel-Chai Basin is located in the Golestan Province. To this end, two data mining models namely support vector machine and boosted regression tree were employed due to their robust computational algorithm. Landslide inventories were recorded through several field surveys using global positioning system (GPS), local information and available organizational resources and corresponding map was created in the geographic information system (GIS). Reviewing several worldwide studies, 12 predisposing factors including proximity to fault, proximity to stream, proximity to road, lithological units, soil texture, land use/ cover, slope degree, slope aspect, altitude, plan curvature, profile curvature and topographic wetness index (TWI) were chosen and the corresponding maps were produced in the geographic information system. In order to evaluate models’ results the receiver characteristic curve (ROC) and 30% of landslide inventories were used. Results showed that the SVM model with the AUC value of 0.82 had better performance on landslide susceptibility zonation over the study area and followed by the BRT model with the value of 0.77. Based on the SVM model results, about 45% of the Chehel-Chai Basin has high and very high landslide prone areas.
Forood Sharifi; Samane Arvandi
Abstract
This research was carried out to; evaluate the hydrological processes (rainfall, runoff, evaporation, infiltration, etc.), study the water capacity, to simulate the behavior of watersheds. After examining a number of simulation models, the SFBM, AWBM2002, SCS and ISDI were selected and adjusted. Data ...
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This research was carried out to; evaluate the hydrological processes (rainfall, runoff, evaporation, infiltration, etc.), study the water capacity, to simulate the behavior of watersheds. After examining a number of simulation models, the SFBM, AWBM2002, SCS and ISDI were selected and adjusted. Data from 15 catchments and a representative watershed were used. The results such as, simulation parameters, runoff threshold, flow duration curve, snow line, flow recession curve, and base flow index are analysed. The results showed that the models, can well simulate the runoff, and are able to estimate response of ungauged catchments, and form a good capability for design and research. In more than 61.5% of the area, after a rainfall of 5 to 10 mm, runoff generates, hence it was concluded that most of the basins are susceptible to flooding. Also, the highest threshold value in the Bandar Gaz basin is 20 mm, with a maximum specific discharge of 0.27 m3/km2. The lowest value was obtained in Azadshahr and Gonbad-Kavoos basins, respectively, equal to 2 and 4 mm, with a specific instantaneous flow rate of 0.16 in the Gonbad-Kavo basin to 0.26 m3/km2 in the basin no. 171. Also, the highest threshold value in the Bandar Gaz basin is 20 mm, with a specific maximum discharge of 0.27 m3/km2. Among the basins of the similar areas, the Delour Qotorchai Basin with an area of 45.2 km2 with a maximum specific discharge of 0.49 m3/km2, the highest and middle Shor basins, with an area of 37.22 km2and Gorgan Bay with an area of 299.26 km2 with a discharge of 0.04 m3/sec/km2.The results indicated that the runoff threshold has a good correlation with precipitation. The results of the dryness model showed that the model with a high correlation coefficient (83%) simulated the discharge.
Ayyub Moradi; Ali Najafinejad; Majid Ownegh; Choghi Bairam Komaki
Abstract
Simulation of runoff and sediment in watersheds require different modelling approaches, each provided for certain condition. Semi-distributed hydrological model (SWAT model) is one of the most widely used modelling approaches in this context. Among the most important spatial information needed by SWAT ...
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Simulation of runoff and sediment in watersheds require different modelling approaches, each provided for certain condition. Semi-distributed hydrological model (SWAT model) is one of the most widely used modelling approaches in this context. Among the most important spatial information needed by SWAT model, is the map of digital elevation model (DEM) which plays an important role in the model results for the exploration of hydrographic properties of watersheds, estimation of the spatial distribution of runoff and sediment load and its accuracy. The aim of this study was to evaluate the effect of different digital elevation models on runoff and suspended sediment in Galikesh watershed, Golestan Province. For this purpose, three types of DEM with the spatial resolutions of 30, 90 and 1000 meters were selected and for a period of 27 years, SWAT model was implemented. SWAT-CUP software and SUFI2 method were used for the model calibration and validation. Nash-Sutcliffe (NS) criterion for discharge and in calibration phase (1990-2007) for the resolutions of 30, 90 and 1,000 meters, was obtained respectively, 0.63, 0.63 and 0.62 and for suspended was obtained respectively 0.69, 0.68 and 0.67 which is considered satisfactory, given the presumed numerical ranges acquired from the previous studies. The amounts of watershed’s annual runoff for the resolutions of 30, 90 and 1000 meters, were respectively, 11.23, 11.30 and 11.39. The results that the use of different of digital elevation models would result in essentially similar results in runoff and sediment estimations, although changes in suspended sediment was slightly overestimated. This is attributable to the inverse modelling logic and lack of considering the parameters which arise directly from the DEM map. , due to data limitations in the Swat model calibration, the digital elevation model used to simulate the runoff did not have much impact on runoff and sediment estimations.
Tayebeh Irani; Mir Hassan Miryaghoubzadeh
Abstract
Land use is referred to the use of land in existing condition that includes all uses in different parts. Land use change is affected by several factors. In this research, land use Changes in the Zarrinehroud watershed and its effect on water quality were investigated in three periods (1987, 2004 and ...
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Land use is referred to the use of land in existing condition that includes all uses in different parts. Land use change is affected by several factors. In this research, land use Changes in the Zarrinehroud watershed and its effect on water quality were investigated in three periods (1987, 2004 and 2013) using Landsat satellite TM and OLI sensors. The results indicate that land use changes in the watershed is going to reduce of pasture and increasing of agriculture. Wilcox and Schuler diagrams were used to evaluate the chemical quality of agricultural water, and drinking water, respectively. Based on the Wilcox diagram, only year 2004 (dry period) was on the C3-S1 class and the remaining years were on the C2-S1 class. Based on the Schuler diagram, the year 2004 (dry period) is considered acceptable in the drinking category and the remaining years are in good drinking category and have no restrictions on drinking. Water quality assessment of the Zarrinehroud watershed shows a decrease in water quality, as a result of increasing the EC, TDS and SAR characteristics in year 2004 that indicates a decrease in river water quality due to land use change and accordance with the occurrence of droughts in the year 2003-2004.
Abdol Rassoul Zarei
Abstract
Drought is an inseparable part of climatic fluctuations which caused to lot of damages to different sections annually. Therefore, drought prediction can be effective in reducing the damages of it. Markov Chain method is one of the drought prediction methods. In this study using climatological data of ...
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Drought is an inseparable part of climatic fluctuations which caused to lot of damages to different sections annually. Therefore, drought prediction can be effective in reducing the damages of it. Markov Chain method is one of the drought prediction methods. In this study using climatological data of 5 synoptic stations of Iran with different climate condition during 1967 to 2014, effect of Markov Chain order (orders 1, 2 and 3) in drought forecast accuracy (Based on SPEI Index) using Markov Chain method were evaluated. Based on the results, transition probability from all drought classes to class 4 (normal) had the most frequency and to class 1 (extreme wet) had the lowest frequency. According to results, in the conditions that observed and predicted drought classes had not difference, Markov with order 3 has the best results. In the conditions that observed and predicted drought classes had one class difference, in 60% of cases Markov with order 3 and in 40% of cases Markov with order 2 has the best results. In the conditions that observed and predicted drought classes had two or three classes difference, Markov with order 3 has the best results. So it’s recommended, to forecast drought using SPEI index and Markov Chain method, in the first grad Markov with order 3 and in the second grad Markov with order 2 to be used.
Mosayeb Heshmati; Yayah Parvizi; Mohamad Gheitury; Mojtaba Sanee; Samad Shadfar; Masud Goodarzi
Abstract
Abstract: land degradation, air pollution, food deficient, poverty as well as inequality are the main challenges worldwide. However, overcome these challenges are impossible without local inhabitants’ participation. The objective of this research was to evaluate the watershed management measures ...
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Abstract: land degradation, air pollution, food deficient, poverty as well as inequality are the main challenges worldwide. However, overcome these challenges are impossible without local inhabitants’ participation. The objective of this research was to evaluate the watershed management measures which measured through joint project by Forests, Rangelands and Watershed Organization (FRWM) and Middle East and North Africa Regions Program for Integrated Development (MENARID) in Razin watershed, Kermanshah, Iran during 2013-16. Local inhabitants were interviewed using questionnaire. The results explored that constructed measures comprise the pit- seeding, rain-fed orchard, stony dam, gabion and dyke. However, most of respondents did not agree with biological measures (pit- seeding, rain-fed orchard) due to limitation for their animal grazing, persuading land-use change and enhancing conflicts among them, while rare inhabitants were willing to rain-fed orchard due to their expects on rangeland ownership and loan opportunity. Approximately 85% of local people confirmed that they did not consult or collaborated during watershed management measures, although they had environmental friend ideas. They believed that mechanical measures are impossible solutions in terms of soil conservation, flood control, runoff harvesting and supplemental irrigation. Overall, local communities worried about climate change and its sever negative impacts on agricultural activities and livelihood, thus watershed management and governance should be taken urgent steps overcome or adapting hits of droughts due to their literacy and experience during recent years. It is concluded that local inhabitant's ideas and their participations should be considered as the necessary step to obtain the effective results and sustaining watershed management measures.
Razieh Saboohi; Hossein Barani; Morteza Khodagholi; Ahmad Abedi Sarvestani; Asghar Tahmasebi
Abstract
Climate change is one of the most important phenomena in recent years have been affected on natural resources and especially the communities whose livelihoods in relation to natural resources, as well as prediction of climate parameters in order to achieve future changes and regard to adaptations to ...
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Climate change is one of the most important phenomena in recent years have been affected on natural resources and especially the communities whose livelihoods in relation to natural resources, as well as prediction of climate parameters in order to achieve future changes and regard to adaptations to deal with climate change is interest of researchers. Therefore, in this study with purpose of previous trend analysis and prediction of precipitation, mean minimum and maximum temperature were used non-parametric Mann-Kendall test and General Circulation Models, HadCM3, respectively. For this purpose, the output data of HadCM3 with three scenarios A1B, A2 and B1 by LARS-WG model were downscale in Semirom region. The results showed that temperature parameters (mean temperature, mean minimum and mean maximum temperature) had increased trend in winter, autumn seasons and annual scale in six studied stations and temperature parameters showed different trend in spring and summer seasons and the annual precipitation is showed negative trend in most of the stations. Also, the results of minimum temperature prediction showed that minimum temperature will generally increase with three scenarios during 21 century and the largest increase in mean minimum temperature compared to the current period is observed in November with more than 0.8 °C increase. The maximum temperature prediction represents a change in the maximum temperature threshold and warming this century in all months of the year, except January and precipitation will increase in all months except June and September using all three scenarios.
Amirhossein Halabian; Nasrin Nikandish; Motahare Akbari
Abstract
In the present study is to identify patterns causing floods in the Mazandaran province to predict these patterns through before the flood could necessary precautionary measures to prevent the damage and take advantage of precipitation. In this reserch, two databases composed of two variables is necessary. ...
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In the present study is to identify patterns causing floods in the Mazandaran province to predict these patterns through before the flood could necessary precautionary measures to prevent the damage and take advantage of precipitation. In this reserch, two databases composed of two variables is necessary. a group of variables and atmospheric data including geopotential height at 500 hPa, zonal wind(uwnd), meridional wind(vwnd) and specific humidity(shum) in Synoptic four hours in the range 0 to 80 degrees north and 0 to 120 degrees east at a spatial resolution 2.5 × 2.5 degree from the database (NCEP / NCAR) have been harvested and other group of precipitation and discharge data in area, during the is 28 Aban to 2 Azar 1388. Then, taking advantage of environmental- circulation approach to mapping 500hpa circulation patterns, atmosphere thickness patterns of the levels1000-500 hPa, moisture flux convergence function and frontogenesis function in 500,925 and 1000 hPa levels on the occurrence of floods. The results of this research have shown that flood generating precipitation in the Mazandaran area are mainly caused by the eastern Mediterranean frontal lows. At the same time, thickness patterns have illustrated intense depressure zone that caused by meeting of cold air mass of the high latitude with humid and hot air mass of the southern Mediterranean. Analysis of the moisture flux convergence(MFC) patterns also have shown that flood generating precipitation are caused by moisture flux of water masses of the Caspian Sea and Black Sea to the Mazandaran area. Analysis of the frontogenesis function maps indicate that occurrence of flood generating precipitation in the study area is caused by the formation and occurrence of front in the Caspian sea and the Black sea in middle levels and east these two of water masses at lower levels of atmosphere (925 and 1000 hPa).
Elham Rezaei; Babak Shahinejad; Hojatola Yonesi
Abstract
One of the important issues in rivers qualitative discussion is the prediction of amount of Total Dissolved Solids (TDS) in water. In this study, the performance of the intelligent models Support Vector Machines (SVM) with different kernel functions, Gene Expression Programming (GEP) and Bayesian Network ...
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One of the important issues in rivers qualitative discussion is the prediction of amount of Total Dissolved Solids (TDS) in water. In this study, the performance of the intelligent models Support Vector Machines (SVM) with different kernel functions, Gene Expression Programming (GEP) and Bayesian Network (BN) was investigated in the prediction of amount of total dissolved solids (TDS) in Kashkan River. For this purpose, quality parameters obtained monthly from Poldokhtar station in Lorestan Province from year 1991 to 2016, including hydrogen carbonate, chloride, sulfate, magnesium, calcium, sodium, electric conductivity, flow rate and PH these parameters were applied to predict the amount of total dissolved sediments of water in this reach. Correlation Coefficient (CC), Nash-Sutcliff coefficient (NS), Root Mean Square Error (RMSE), and bias were used to evaluate the performance of the models. The results showed that in all three models, the combined structures have acceptable accuracy. Also, based on the evaluation criteria, Support Vector Machines with kernel of the radial base functions (RBF) had the highest accuracy 0.982 and the lowest root mean square error (mg / lit) 0.232, and the lowest bias 0.001 and the Nissan Sutcliff coefficient 0.963 compared to other models.
Mehran Zand
Abstract
This research was designed and implemented with the aim of determining the Effectiveness of Reclamation Operations of watershed management implemented by the forest, rangeland and watershed management organization in increasing the carbon sequestration potential of the land and selecting the optimally ...
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This research was designed and implemented with the aim of determining the Effectiveness of Reclamation Operations of watershed management implemented by the forest, rangeland and watershed management organization in increasing the carbon sequestration potential of the land and selecting the optimally implemented patterns. In order to estimate the carbon sequestration of three basins were selected as three sites. Then, samples were weighed and their weighs were identified according to plot in each area and hectare. After that, 10 grams of each sample was transferred to the laboratory and the amount of sequestration was determined per unit area.The Research results show that sample basin of Rimeleh with 2025 kg per ha is the maximum carbon sequestration amount while control sample Abkandari Kohdasht with 122 kg has the minimum carbon sequestration among biological projects.From biological operations. point of view, seeding project with wheat in Rimeleh basic with 1064.56 kg per had the best performance in terms of carbon sequestration and was ranked highest. According to the results of experiments and analysis of data from the study sites, was determined In Bio-mechanical project of flood spreading Rumshkan, that they have been cultivated Eucalyptus species ,Conditions of carbon sequestration are better than the other varieties cultivated in Rimele and Koohdasht and the average rate is 37/31 ton/ha. The amount of soil carbon sequestration from mechanical operations was estimated to be 45.7, 45.4, 78.4, 54.8 ton / ha Respectively for the three catchment basins of Rimla, Rumshkan and Kohdasht, and the average of the control samples was 26 tons per hectare. Finally acccordind to results of this research Flood spreading Rumshkan project with carbon sequestration of almost 78 tons in each hectar is a successful project from carbon sequestration with a correct management and for mechanical and biological operations of watershed.
Abstract
Homogeneous sub watershed Are useful for comparison and better understanding of the complex structure of watershed and thereby facilitating the development and management approaches specific to each class to deal with the destructive phenomena such as soil erosion, drought and flood. In this study, the ...
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Homogeneous sub watershed Are useful for comparison and better understanding of the complex structure of watershed and thereby facilitating the development and management approaches specific to each class to deal with the destructive phenomena such as soil erosion, drought and flood. In this study, the database contains 6 groups of information such as climatic and socio-economic, topography, soil, water, remote sensing were studied.These Factors converted to raster and then the pixel data converted to text data (ASCII). So matrix was produced with dimensions of 27 * 147 506. Eigenvalues and the variance associated with each factor showed that 6 first component includes a total of 83.27% of the changes. In order to select the optimal number of clusters and clustering evaluation and validation of the method, hierarchical clustering and discriminant analysis and clustering using k- mean cluster of the data was performed. Karoon Sub watersheds were classified into 16 groups.
Reza Talaei; Mohsen Shariat Jafarei; Bayramali Beyrami
Abstract
Landslides are the major causes of erosion and sediment yield in the sloping and mountainous basins. However, evidence suggests that the amount of sediment to the river of the mountainous regions in Ardabil province due to landslides is significant, but in quantitative terms it has not been provided ...
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Landslides are the major causes of erosion and sediment yield in the sloping and mountainous basins. However, evidence suggests that the amount of sediment to the river of the mountainous regions in Ardabil province due to landslides is significant, but in quantitative terms it has not been provided the certain value based on scientific research for it. In this study, the subject was evaluated in the Balekhlou-Chay catchment of Ardabil province using data extracted from the aerial photographs, field investigations and the sediment discharge measured data at Pole-Almas hydrometric station. Sediment volume in the sediment measurement stations associated with the catchment was estimated by determining the relationship between flow rate and it′s corresponding sediment discharge. It was attempted to compare the estimated amount of sediment at different time periods with its amount in the periods of activity of landslides and to determine the possible effects of the landslides in increasing erosion and sediment yield in the catchment. The noted large landslides have caused a significant increase in the sediment load of the available rivers. The effects of these slides can be observed in the suspended load passing through Pol-e-Almas station. The mean of the suspended sediment concentration of Balekhlou-Chay catchment has been estimated about 46566.30 tons per year based on sediment discharge values from field data during 40 years (from 1972 to 2001), however the mean of the suspended sediment concentration is 30831 tons per year based on sediment discharge values from field data during 36 years, which means with the elimination of the data related to landslide years (from 1980 to 1983). In conclusion, according to the calculated sediment carried by the Balekhlou-Chay river after the occurrence of the Sarighaye and Ilanjigh landslides during the period of 4 years (from 1980 to 1983) has been increased rapidly.
Mohammad Reza Dahmardeh Ghaleno; Mohammad Nohtani; Sadegh Askari Dehno
Abstract
The purpose of this research is to study the changes in some features of the topsoil and vegetation in the land affected by flood and comparing its results with the control area in koh khajeh flood spreading station in hamoon area of Sistan. For this purpose, four sites were considered as flood spreading ...
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The purpose of this research is to study the changes in some features of the topsoil and vegetation in the land affected by flood and comparing its results with the control area in koh khajeh flood spreading station in hamoon area of Sistan. For this purpose, four sites were considered as flood spreading area and two sites were selected as control area. Samples were taken in six sites using the random-systematic method. To this aim, 3 transects of 100 meters was established in each field and each one had 10 plots of 1 square meters regarding the dispersion of vegetation. Canopy cover percentage and density were calculated through use of plots and clipping and weighing was used to measure current year's growth as production. Also, to measure soil properties, sampling along each transect and in six points (3 points in shrubs understory and three points in bare soil), and factors as EC, pH, nitrogen percentage of the soil, and organic matter percentage were calculated. In order to compare the results regarding soil features, we used 2*2 factorial tests and for the factors regarding vegetation we used non-paired t test in spss. Data normality was assessed using Kolmogorov test. The results indicated that flood water spreading has a significant effect on canopy cover percentage and plant production respectively in probability level of 5 and 1 percent, but there is not significant difference between vegetation density in flooded and control area. Results showed that flood has led to significant increases in soil nitrogen percent and organic matter as well as low acidity and EC in probability level of 5 %.at the same time, organic matter, nitrogen and acidity are low compared to shrub understory soil in both treatments. However, EC in soil under shrub is higher than bare soil in both treatments
Hassan Goleij; Amirhamze Haghiabi; Mojtaba Saneie; Hojattallah Yonesi
Abstract
The percentage of flow diversion is the major cause of the formation of dimensions of separation zone such that with increasing the percentage of flow diversion, width and length of the separation zone decreased in the basic and sill experiments. However, by adding a 10ᵒskimming wall, the changing ...
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The percentage of flow diversion is the major cause of the formation of dimensions of separation zone such that with increasing the percentage of flow diversion, width and length of the separation zone decreased in the basic and sill experiments. However, by adding a 10ᵒskimming wall, the changing trend is different. At low percentage of flow diversion, dimensions of the eddy area decreased significantly and it increased with increasing the percentage of flow diversion. However, in general, the simultaneous usage of a 10 degree skimming wall and sill structures compared to basic and sill experiments, dimensions of separation zone in lateral intake decreased and the useful width of outlet flow at lateral intake increased and the separation zone and sediment accumulation at the entrance of lateral channel decreased. By examining the effect of the Froude number of flow (inlet flow) on dimensions of the eddy region, this parameter did not have any significant effect on it and its low impact could be connived. By investigating the width of separation line of flow in the surface and near the bed of channel bend, it was found that the flow diversion rate was the most important factor affecting this hydraulic parameter; since, at surface level of flow with increasing flow diversion ratio, this parameter increases and due to the creation of secondary flow and the change of surface flow pattern under the influence of the simultaneous application of a 10 degree skimming and dike structures, this parameter increases more. However, near the bed, in basic and sill experiments, this parameter increases with increasing flow diversion rate. However, the simultaneous application of 10-degree skimming and sill structures, the width of separation line of flow near the bed reduces by increasing the diverted flow
Zahra Veiskarami; Babak Pilehvar; Ali Haghizadeh
Abstract
This study aimed to detect the effects of anthropogenic disturbance on vegetation changes based on conservatism species concept and its relation to environmental factors in two protected vs disturbed area. The study area, Shine Qelaii gall oak forests, located in 88 Km from the north west of Khoramababd. ...
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This study aimed to detect the effects of anthropogenic disturbance on vegetation changes based on conservatism species concept and its relation to environmental factors in two protected vs disturbed area. The study area, Shine Qelaii gall oak forests, located in 88 Km from the north west of Khoramababd. Multiscale sampling plots were used randomly to collect data on forest floor vegetation, trees, soils, and other environmental factors. Among collected plant specimens, conservatism species were identified and DCA and CCA ordination methods were applied to determine correlation between plant species and environmental factors, plant diversity also were investigate by nonparametric numerical diversity indices. The most effective environmental factors on distinction among vegetation communities were determined by PCA ordination method. Based on the results, more invasive species and less richness and diversity indices were seen on the disturbed forest type compare to the protected one. A positive correlation was seen in ground flora vegetation and soil nutrients. Altitude, canopy cover, exposure, OC, K, N, P, clay, sand, and bulk density were the most effective environmental factors on vegetation types. This study showed that conservatism species concept together choosing two close and same watershed can eliminate confused factors and resulted to more accurate determination of conservation management effects on vegetation composition
arezoo kheyrkhah
Abstract
Correct and consistent uses of natural resources preserve this valuable wealth. Using optimization knowledge can assist us to achieve this object. Thus, this study aims to compare linear programming as a classical method of optimization with genetic evolutionary algorithm for land use optimization of ...
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Correct and consistent uses of natural resources preserve this valuable wealth. Using optimization knowledge can assist us to achieve this object. Thus, this study aims to compare linear programming as a classical method of optimization with genetic evolutionary algorithm for land use optimization of the Bayg watershed. Results showed that linear programming reduced dry farming acreage and increased the acreage of irrigated agriculture. After minimization, surface runoff and sediment yield declined by 1.16, 12.91 percent, respectively. Genetic algorithm led to an increase in rangeland, irrigated agriculture and horticulture acreages, while almond orchard and dry farming acreages were reduced. Furthermore, surface runoff and sediment yield declined by 13.95 and 31.99 percent, respectively. Linear programming acted stronger in satisfying the constraints, as compared with genetic algorithm. The constraint “total acreage” was satisfied by linear programming, while genetic algorithm could not meet this constraint. Sensitivity analysis of linear programming showed that the most critical factor in minimizing runoff and sediment yield function was the coefficient of dry farming with a reduced cost of 67.52. Results also established that the constraints “total acreage and minimum acreage of rangeland” with the shadow prices of 397.40 and 233.28, respectively had the highest negative impact on the optimal solution. Meanwhile, the constraints “maximum acreages of irrigated horticulture and almonds garden” with the shadow prices of -134.97 and -118.44, respectively had the highest positive impact on the optimal solution. As a general conclusion it can be stated that in land use optimization problems with a large number of constraints, genetic algorithm show poorer performance in satisfying constraints, as compared with linear programming.
Hassan Moghim; Masoud Nejabat
Abstract
From the viewpoint of landslide occurrence, Parsian dam Watershed is one of the high risk regions for landslide hazard based on its geological and climatological conditions. Landslide occurrence usually make huge damages and also high amount of sediments. Landslide control and management is planned according ...
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From the viewpoint of landslide occurrence, Parsian dam Watershed is one of the high risk regions for landslide hazard based on its geological and climatological conditions. Landslide occurrence usually make huge damages and also high amount of sediments. Landslide control and management is planned according to Landslide Hazard Zonation (LHZ) that is obtainable through empirical models. The aim of this research was to assess the efficiency of two empirical models, Modified Nilsson and Relative Effect in LZH. First, prepared maps such as landslide distribution, slope, geology, land use, land cover, roads, drainages, faults, isohyet and hypsometric were imported into GIS environment and then the landslide hazard zonation was carried out by applying Modified Nilsson and Relative Effect models. Capability assessment of two models and determination of the more efficient one were evaluated using two statistical analysis methods namely quality summation (Qs) and correlation coefficient (R). Comparison of results from above two models with real map of happened landslides at Parsian dam Watershed showed that the relative effect model with quality summation of 1.00 and correlation coefficient of 0.941, is more efficient for landslide hazard zonation in Parsian dam Watershed.
Fahimeh Mirzaei-Nodoushan; Omid Bozorg Haddad; Majid Khayat Kholghi
Abstract
In groundwater resources management, continuous monitoring of wells discharge and charge and groundwater quantitative and qualitative variations are very important. Groundwater monitoring network could provide information on quantitative and qualitative variations in groundwater situations. Hence it ...
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In groundwater resources management, continuous monitoring of wells discharge and charge and groundwater quantitative and qualitative variations are very important. Groundwater monitoring network could provide information on quantitative and qualitative variations in groundwater situations. Hence it would be used to predict the behavior of the aquifer in the future. This study describes an optimizing method to design the optimum groundwater-level monitoring network in aquifer of Eshtehard. Two scenarios were considered to optimize the locations of the observation wells: (1) exploring optimal locations of existing observation wells and (2) adding optimal observation wells to existing well network. Kriging method was utilized to estimate groundwater-level for preparing the database. Optimization of groundwater monitoring network with two objectives: (1) minimizing root mean square error and (2) minimizing number of wells, was implemented by non-dominated sorting genetic algorithm (NSGA-II). The results show that by using this method it is possible to remove redundant wells in a monitoring network or to add new wells in case of shortage of observation wells in a network having acceptable accuracy.
