Saeid Afkhamifar; Amirpouya Sarraf
Abstract
Today, due to the importance of sustainable groundwater management, groundwater level modeling and forecasting are used to assess and evaluate water resources. The purpose of this study is to evaluate the performance of two models of Extreme Learning Machines (ELM) and Artificial Neural Network (ANN) ...
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Today, due to the importance of sustainable groundwater management, groundwater level modeling and forecasting are used to assess and evaluate water resources. The purpose of this study is to evaluate the performance of two models of Extreme Learning Machines (ELM) and Artificial Neural Network (ANN) and the combination of two models with wavelet transmission algorithms (W-ELM and W-ANN), which ultimately to increases the predictive power and optimization of input weights (the weights between the input and hidden layers) of models, Quantum Particle Swarm Optimization algorithm (QPSO) has been used. Also, in this study, the data of Ground Water Level of observation wells (GWL), precipitation (P) and average temperature (T) of Urmia Plain aquifer with a time series of 36 years (1981 – 2017) which were collected on monthly scale, are used. Also, in order to evaluate the performance of models, correlation coefficient (R), Root Mean Square Error (RMSE) and Mean Absolute Error (MAE) were used. In this regard, 80% of the data (September 1981 to August 2010) are used for training section and 20% of data (September 2010 to August 2017) used for the test section of models. Based on the results of this study, the hybrid model of W-ELM-QPSO with correlation coefficient (R) 0.991, 0.983 and 0.975, respectively for periods of one, two and three months in the test section, have a better performance than other models and also in addition to predicting power, this model has a high speed in terms of training and testing speed than other models.
Zahra Nik; Kouros Yazdjerdi; Hadi Abdolazimi
Abstract
Morphometric analysis is considered as quantitative evaluation of geometric features landforms and landscape. In the study of basin tectonic features, the use of some morphometric parameters can provide very substantial information. Gavkoshak Basin with an area of 46.73 km2 is located in Zagros simply ...
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Morphometric analysis is considered as quantitative evaluation of geometric features landforms and landscape. In the study of basin tectonic features, the use of some morphometric parameters can provide very substantial information. Gavkoshak Basin with an area of 46.73 km2 is located in Zagros simply folded belt. The objective of this research is to use the morphometric indices such as hypsometric integral, basin shape, stream length-gradient, asymmetric factor, and the valley width/height ratio. As a result, these indices are converted to the tectonic activity index. This index can be used to assess the overall performance of the region's tectonic activity.Morphometric indices of area are studied by dividing this area into 43 sub-basins, using the Digital-Elevation Model (DEM) and Geographic Information System) GIS). Morphotectonics index method with the use of geographic information systems provide procedures and a powerful tool for estimating tectonic activity in the region. It should be borne in mind that the results of these indices can show different values in different sectors. By examining the relative index of tectonic activity, the basin in this research is divided into two parts namely active (25.6% of the watershed) and semi-active (74.4 % of the watershed). Through statistical analysis, the area under investigation includes four clusters: cluster one with 91. 83% similarity, cluster two with 95.19% similarity, cluster three with 96.18% similarity, and cluster four with 91.09% similarity. In this way, homogeneous regions were determined based on clustering algorithm ward. The active tectonic basin in this research can be studied in another research project, using other morphometric parameters.
Aliakbar Noroozi; Morteza Miri; Davoud Nikkami; Tayeb Razi; Amir Sarreshtehdari; Ziaedin Shoaei
Abstract
The purpose of this study was to investigate the oak forest dieback with respect to drought occurrence, soil moisture changes and dust occurrences factors in Ilam, Kermanshah, Lorestan and Chaharmahal and Bakhtiari provinces of Iran. The data used were field surveys collected through GPS, MODIS satellite ...
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The purpose of this study was to investigate the oak forest dieback with respect to drought occurrence, soil moisture changes and dust occurrences factors in Ilam, Kermanshah, Lorestan and Chaharmahal and Bakhtiari provinces of Iran. The data used were field surveys collected through GPS, MODIS satellite imagery, GLDAS Soil Moisture, dust and precipitation data of the meteorological stations of the provinces during an 18-years period (2000-2017). The results of the study of greenness values of the forests in the study area showed that the first decline occurred in 2005 and repeated more severely with much wider spatial extent in 2008. Investigation of the relationship between drought events and its spatial and temporal variations with the changes in forests greenness of the study area showed that the reduction in precipitation amount is one of the main reasons for forest greenness reduction in the study area. The increased frequency of periods of rainfall shortage and drought duration, especially at 9 and 12-month time scales, showed a significant relationship between drought occurrences and forests greenness in the study area. The results indicated that by decreasing precipitation drought periods increased, soil moisture decreased, and dust storm occurrences increased. As a result, in most of the years, with decreasing soil moisture and increasing dust storms, the forests greenness of the study area has decreased and vis versa. Therefore, there is a direct relationship between soil moisture and forest greenness while an inverse relationship exists between dust and forest greenness.
kianfar payamani; Ebrahim Karimi Sangchini; iraj vayskarami; Mehran Zand
Abstract
IntroductionManaging a pervasive and effective phenomenon such as drought in different sectors of the economy requires close cooperation and careful planning. Lack of strategic drought planning and delays in decision-making have increased costs to reduce drought damage. The aim of this study was to develop ...
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IntroductionManaging a pervasive and effective phenomenon such as drought in different sectors of the economy requires close cooperation and careful planning. Lack of strategic drought planning and delays in decision-making have increased costs to reduce drought damage. The aim of this study was to develop strategic for drought adaptation using the SWOT model in Lorestan Province. Materials and methodsIn this research, the methods of reviewing sources and interviewing with a questionnaire were used in order to provide macro strategies to adapt to drought. For this purpose, the current status of ecological resources, environmental changes, economic sectors and their dependence on water resources, population and employment, management of ecological resources, organizations and institutions were analyzed, then by reviewing the upstream laws and documents, interview with resource managers, local and national decision makers, experts, published background and other available information identified the causes of problems and obstacles to drought management in the province. The statistical sample consisted of 27 experts and scientific and executive experts were selected. Scoring was done on two occasions by experts, and finally, by averaging the opinions of experts and scientific and executive experts, the weight of internal and external factors was determined. In the final stage, in addition to identifying important factors in each of the criteria of strength, weakness, opportunity and threat, necessary management strategies were determined based on the conditions of Lorestan Province through SWOT analysis. These issues were categorized in the form of environmental opportunities and threats and internal strengths and weaknesses, then analyzed by SOWT analysis approach and Delphi method. Results and discussionThe study of strength factors shows that the existence of companies and organizations with resource monitoring units in the province with a weight of 0.25 has a higher effectiveness and degree of importance among other factors. Lack of proper planning and organization for monitoring and evaluation of drought weighing 0.33 has a very high effectiveness among the factors of poor adaptation to drought in the province. Among the opportunities, the factor of technological advances in the field of precision agriculture with a weight of 0.1 have a very high effectiveness. The factor of endangering the livelihood of farmers in case of drought is the most effective among the studied factors of threats with a weight of 0.22. Factors of irrigation of lands in some areas with polluted water and gradual destruction of agricultural soil and population increase and as a result increase in demand for water with a weight of 0.02 were recognized as having the least effectiveness among the threats of drought adaptation in Lorestan Province. ConclusionAfter scoring using the Delphi method, it was found that the presence of faculties and centers of agricultural education and natural resources in Lorestan Province was recognized as the most important strength. But despite this strong point in the province, unfortunately, the lack or inappropriateness of available data and information for the purpose of monitoring and evaluating the effects of drought is known as the main weakness. According to these results, in the direction of the conservative strategy, the strategy of balancing aquifers with the priority of aquifers with a negative water balance was suggested. The government's support for water harvesting projects at the level of cities and villages and the monitoring of better water management in cities provide suitable opportunities to improve the ability of farmers to deal with the negative effects of drought. The final result has been the presentation of drought coping strategies for different regions of the province in the areas of surface and groundwater supply, irrigated and rainfed agriculture, urban and rural drinking water and river water environment.
Nader Oveisi; Reza Jafarinia; Lobat Taghavi; Jamal Ghoddousi
Abstract
Preservation of river ecosystem depends on the quantity and quality of the river flow regime, and the construction of large dams causes quantitative and qualitative changes in downstream rivers, so it is necessary to pay attention to the quality of rivers in addition to the quantity of water needs. Therefore, ...
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Preservation of river ecosystem depends on the quantity and quality of the river flow regime, and the construction of large dams causes quantitative and qualitative changes in downstream rivers, so it is necessary to pay attention to the quality of rivers in addition to the quantity of water needs. Therefore, in this study, a 22 km long section of the river at the bottom of Taleghan Dam located in Alborz Province (103 km of Karaj City) was selected with the aim of determining the minimum flow quantitatively in accordance with aquatic biological standards. Based on this, the average annual and monthly flow of the river in four stations in the study period with an approximate distance of six km from each other was estimated. Since there is a relationship between river hydraulic parameters such as depth and flow velocity with the habitat of the target species (such as the index fish), the measured field value was calculated to determine the optimal habitat conditions. Also, in this study period, to compare the possible change in the concentration of pollutants, each of the water quality parameters with its standard concentration for salmon survival was used as an ecological indicator and it was found that among 17 physicochemical parameters of water quality, Sulfate parameter (SO4) and its concentration can be considered as the most appropriate indicator for determining the minimum environmental flow for red-spotted trout in the Taleghan River. SPSS-24 software and One Sample T Test method were used to determine the mean concentration comparison test with standard concentrations of water quality parameters for Salmon biology.
mehdy teimory; Asadollah Khoorani; Masoud Bakhtiarikia
Abstract
Runoff estimation is a fundamental activity in water resource management, and plays an important role in the best usage of a hydrologic system. Runoff estimation is usually based on different hydrological models. Calculation of intensity and duration of precipitation is not efficient in the most regions ...
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Runoff estimation is a fundamental activity in water resource management, and plays an important role in the best usage of a hydrologic system. Runoff estimation is usually based on different hydrological models. Calculation of intensity and duration of precipitation is not efficient in the most regions of the globe for determining general properties of precipitation because these calculations are based on pointed data of ground observation, whereas precipitation is a spatial phenomenon. The aim of this paper is simulating monthly runoff of Kalam Basin based on satellite data of precipitation using SWAT model. In order to running SWAT, precipitation data of TRMM and GPCP, temperature, relative humidity, wind speed and solar radiation is used for the period of 1998 to 2012 for study area. Also, soil and land use maps and DEM are converted to the model format for study area. Period 2001 to 2009 is used for calibration and 2010 to 2012 for validation of the model. Nash Sutcliffe Efficiency Index and Weighting Coefficient was 0.41, 0.44, 0.32 and 0.37 for TRMM and GPCP respectively for calibration and 0.52, 0.71, 0.10 and 0.19 for validation. The results indicated that SWAT achieved a reasonable fit after calibration by using TRMM and not reasonable using GPCP data the model.
Golamabas Falah Qalhar; Rasol Sarvestan
Abstract
The aim of this study is to predict and verify the number of days of dust phenomenon selected stations in Khuzestan Province using Box-Jencks model. Study in eight selected stations of the province to compare the Box-Jenkins model and predict the effect of dust has been done. Using the Minitab 17 software ...
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The aim of this study is to predict and verify the number of days of dust phenomenon selected stations in Khuzestan Province using Box-Jencks model. Study in eight selected stations of the province to compare the Box-Jenkins model and predict the effect of dust has been done. Using the Minitab 17 software Box-Jykyz time series model, number of days of dust monthly was checked and best models were fitted, the accuracy of the model using normal distribution of residuals, assuming constant variance, charts left over time, Mvntv Perth test was confirmed. Finally, Arc-GIS10.4 software was used for output mapping. Results showed that the best monthly pattern for Ramhormoz, Aghajari, Behbahan, Abadan, Dezful, Omidiyeh, Ahwaz and Masjed Soleiman are ARIMA (2,0,1)(1,1,1), ARIMA (2,1,1)(1,1,1), ARIMA (3,0,1)(2,1,1), ARIMA (1,0,1)(2,1,1), ARIMA (2,0,1)(2,1,1), ARIMA (3,1,1)(1,1,1), ARIMA (3,0,1)(1,1, 1) and ARIMA (4,0,3) (1,1,1), respectively. These models have a good accurately for predicting dust and the numbers of dusty days for 2018 to 2027. Also, results showed that Agajari, Abadan and Masjed Soleiman are more exposure with dust phenomena in Khuzestan Province that needs for further attention to city officials and planners in facing with this phenomena.
Rahim Kazemi
Abstract
During the last two decades, there has been a lot of research on the base flow issue in the country, but so far, no comprehensive and specific article review of base flow research has been conducted, untill the various aspects of this issue be identified and the cases ignored, be introduced and addressed. ...
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During the last two decades, there has been a lot of research on the base flow issue in the country, but so far, no comprehensive and specific article review of base flow research has been conducted, untill the various aspects of this issue be identified and the cases ignored, be introduced and addressed. In this research, first, by literature review at the global and national level, the progress of studies in different fields of this issue were investigated and then dissertations, articles and reports published in international journals and related conferences have been classified and discussed for the past two decades. The main purpose of this research was to identify issues of research at base flow and to identify lesser and overlooked issues in country research. The articles reviewed in this research were analyzed based on spatial domain, research method, theory, data analysis techniques and topic. Results showed that research orientation in base flow in Iran can be divided into four general categories; 28.21% of studies related to applied orientation; 37.18% to comparison and introduction of proper baseflow separation method; 19.23% to investigation of factors affecting base flow and 15.38% to general use and description of hydrological conditions of the study area. The overall conclusion, indicates limited studies, lack of innovative, and focus on the use of conventional and repetitive methods and also lack of attention to this issue by scientific and research centers of the country.
Saeedeh Khaledi; Mohammad Nohtani; Mohammad reza Dahmardeh ghaleno
Abstract
In arid areas, water resources management and utilization is of great importance in minimizing the damage caused by water shortages in these areas while maximizing water resources efficiency. The present research aims to assess water resources management in Sistan with an approach to cope with dust storms ...
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In arid areas, water resources management and utilization is of great importance in minimizing the damage caused by water shortages in these areas while maximizing water resources efficiency. The present research aims to assess water resources management in Sistan with an approach to cope with dust storms and desertification phenomena using lexicographic goal programming method. Lexicographic goal programming is one of the most important multi-objective optimization problem solving methods. GAMS programming was considered to design research model. The results showed that according to the experts, in order to coping with dusts phenomenon, followed by meeting domestic demands in Sistan, water transfer priorities are related to critical control point of Hamoon Wetland and plantation areas in wind sedimentation. For this, once research model was run and under optimal water resources management, in addition to meeting all domestic consumption demands, the amount of water transmitted to Hamoon Lake to supply its minimum water requirement was 61.4 million cubic meters. Hence, the water needed for the stabilization of the critical control point of Hamoon Wetland was fully supplied. In addition, under optimal management conditions, water transportation to plantation farms of northern Mohammad Shahkarm and Jazinak cities was increased by 13.22 and 7.76 million cubic meters, respectively, i.e. up to twice a current value. As a result, all of water demands in these sectors have been met completely. According to the results, under optimal water management conditions in addition to meeting basic needs, water transferring to critical control point of fine grain sediment origins to stabilize them.
Zeynab Hosseinpour; Mahdi Radfar; Rasoul Mirabbasi
Abstract
One of the resources that have been severely affected by drought is groundwater, however it has been considered less than other water resources. Due to the recent droughts especially in the central regions of Iran, investigating the impact of droughts on water resources is very important. The main aims ...
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One of the resources that have been severely affected by drought is groundwater, however it has been considered less than other water resources. Due to the recent droughts especially in the central regions of Iran, investigating the impact of droughts on water resources is very important. The main aims of this study are characterization of meteorological and hydrogeological droughts, assessment the effects of drought on groundwater level fluctuations and determining the critical regions of Shahrekord Plain Aquifer. For this purpose, modified Standardized Precipitation Index (SPImod) and Groundwater Resource Index (GRI) were used to assess meteorological and groundwater droughts, respectively. Also, the cross-correlation test was used to investigate the relationship between the meteorological drought and the groundwater drought. In this research, the monthly precipitation data of Shahrekord synoptic station and monthly groundwater level data of 35 piezometers in this plain in the period of 1984-2015 were used. Based on the result of GRI index, Shahrekord Aquifer was divided into three regions which cover the north and northwest, central and south-east and southwest. The results of correlation between modified SPI in various time scales of 1, 3, 6, 9, 12, 18, 24 and 48 months and GRI index indicates the highest correlation between 18-month modified SPI and GRI. The results also showed that the effect of meteorological drought on GRI index appears with 6 and 18-month delay on northern and central areas, respectively, and without delay on the South West of the Shahrekord Aquifer.
Volume 10, Issue 4 , January 2019
seid omid aleyasin; bahman shamsesfandabad; Hamid Toranjzar; abas ahmadi; Shahro Mokhtari
Abstract
Abstract: Wetlands are one of the most productive ecosystems in the world. They provide a unique and rich habitat for creature .they also perform a wide range of economic and service functions such as water conservation, runoff regulation, water quality treatment and recreational services. The aim of ...
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Abstract: Wetlands are one of the most productive ecosystems in the world. They provide a unique and rich habitat for creature .they also perform a wide range of economic and service functions such as water conservation, runoff regulation, water quality treatment and recreational services. The aim of this study was to evaluate the ecosystem health of Meyghan Wetland of Arak based on different methods. To evaluate the Meyghan Wetland of Arak and also to evaluate the status of benthic organisms and other parameters, sampling of sediments of the wetland floor was performed. Sampling was performed at 10 points of the wetland and at 5 replications at each point. Several indicators were used to assess the health of Meyghan Wetland. Which included a biotic-index (BI) based on the work of Borja et al. (2000). In addition to the above, the main framework includes bio-indicators, heavy metal pollution index and water quality index, which have been considered in this study. The ecosystem health of Meyghan Wetland was evaluated based on the mentioned indicators and the map of ecosystem health of Meyghan Wetland was prepared. The results of this study showed that except for the nickel, zinc and lead as well as pH, for other elements (EC, Na, Cl, Mg, Ca, HCO3, SO4 and TDS), the lowest and highest values belong respectively To stations 3 and 6. The high amount of these elements in station 6 can be due to the activity of sodium sulfate factory in the northern part of the wetland, which causes changes in the wetland ecosystem by removing sediments from the wetland floor. In the case of copper, zinc and lead, the lowest concentration is seen in the northwestern part of the wetland and the highest concentration is seen in the western and southeastern parts of the wetland.
Ali Abdi Nam; Mohammad Mahdavi
Volume 1, Issue 1 , May 2009, , Pages 9-20
Abstract
Existing coarse materials produced during surface erosion in the marl watershed basins in tributary beds and impermeable subsurface layers (marl layers) lead to produce a subsurface flow. This subsurface flow can be used in order to develop vegetation cover in order to make the biological stabilization ...
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Existing coarse materials produced during surface erosion in the marl watershed basins in tributary beds and impermeable subsurface layers (marl layers) lead to produce a subsurface flow. This subsurface flow can be used in order to develop vegetation cover in order to make the biological stabilization of tributary beds. This method is very useful in the watersheds basins in which were performed the watershed practices such as Gabion dams and sediment ponds. This paper was the result of the research plan, which was considered as development of vegetation cover to biologically stabilize the tributary beds in Sardehat village areas as a split plot factorial statistical design. The three kinds of trees including: Almond, Elaeagnus, and Acacia as the main treatments, and the mixed of soil with manure and clay, and natural soil as the sub-treatments in three replications were studied in the selected area. During the performance of this study variables like stump diameter, height growth, and canopy cover were measured. Final results showed that considering the planting pattern Almond, Acacia and Elaegnus, and without considering the planting pattern Elaeagnus, Acacia, and Almond were preferred respectively in order to stabilize biologically the marl tributary beds.
Gholamreza Chamanpira; Gholamreza Zehtabian; Hasan Ahmadi; Arash Malekian
Abstract
Drought is the most hazardous natural phenomenon. Although not preventable, its negative effects can be reduced through taking some measures. One of the systems severely affected by drought while less considered is the groundwater. In this study, drought status and its impact on groundwater resources ...
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Drought is the most hazardous natural phenomenon. Although not preventable, its negative effects can be reduced through taking some measures. One of the systems severely affected by drought while less considered is the groundwater. In this study, drought status and its impact on groundwater resources was investigated in Alashtar Plain using Standardized Precipitation Index (SPI) at monthly, quarterly, and annual scales and the Groundwater Resource Index (GRI) during the statistical period of 1991-2010. After data collection, statistical errors were corrected by subtraction and ratios method. Then, to determine the status, SPI and GRI were calculated with DIP software on an annual, seasonal, and three, six, nine, 12, 18, 24, and 48-month time scales for Alashtar Plain. Then, according to SPI and GRI value, the moisture status were determined for each period. Results indicated that the trend of plain meteorological and groundwater drought is negative. Correlation between SPI at different time scales with and without the time delay and with average groundwater level and GRI was analyzed. Statistical analysis showed that SPI was significant at the level of 0.01, in the 24-month time scale without any time delay with mean groundwater level and GRI and had the highest correlation coefficient, suggesting the impact of drought on Alashtar plain groundwater. Regression relation between the mean level of the water table and SPI_24 showed that 64.4% of the variance at the mean level of water table was affected by SPI_24 and 35.6% was affected by other factors. Drought magnitude (DM) analysis showed that meteorological and groundwater droughts are consistent with winter and autumn, respectively. Undoubtedly, optimized utilization management, especially in spring and summer, may have a critical impact on preventing damages to the groundwater resources of the region.
Ali Rezaei
Volume 2, Issue 1 , May 2010, , Pages 11-17
Abstract
Increasing runoff coefficient and flood intensity and extending dry land areas over the country basins are due to the destruction of vegetation cover. For monitoring the trend of temporal variation, maximum peak flows and maximum 24 hr rainfall data have been gathered from all climatologic and hydrometric ...
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Increasing runoff coefficient and flood intensity and extending dry land areas over the country basins are due to the destruction of vegetation cover. For monitoring the trend of temporal variation, maximum peak flows and maximum 24 hr rainfall data have been gathered from all climatologic and hydrometric stations of Ghizilozan basin. The acquisition data repaired and standardized within a period of 30 years. Then the data were divided into three categories with period of 10 years and finally six categories with period of 10 to 30 years were produced. The mean of variables for every period was calculated based on two years return period by fitting the distribution function of Pearson type III to selected data series. The mean of every category plotted with time period and fitted a line to them. The results showed that based on Kendall’s Tau method, there are significant and positive harmonizing between measured variations respect to time only in two climatology stations named Gitoo and Salamatabad and so two hydrometry stations named Sarcham and Dehgolan and in the others there aren’t any positive or negative harmonizing of data variations respect to time. But the slope of regression line of maximum 24 h of annual rainfall as an index of climate variations to the time, equal 0.031 and in contrast the slope of regression line of peak flow to time equal 0.059. Therefore, the slope of peak flow is 1.9 times of maximum 24 h of annual rainfall with time. This finding says that the vegetation cover because of dry land extending is destroyed and runoff coefficient and flood intensity is increased at studied basin.
Fateme Mohammadzadeh; Mohammadreza Ekhtesasi; Seyed Zein Alabedin Hosseini
Abstract
Underground aquifers are one of the main sources of water supply in most parts ofIranwhich are affected by natural and manmade factors in recent decades. Land and geological formations are from the natural factors in any region. In this study, the investigation of the quality of groundwater resources ...
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Underground aquifers are one of the main sources of water supply in most parts ofIranwhich are affected by natural and manmade factors in recent decades. Land and geological formations are from the natural factors in any region. In this study, the investigation of the quality of groundwater resources and their correlation with geology formations were considered. For this purpose, using the geological map of the area geological formations were extracted. Then, to determine the water brigade, the qualitative data of 76 operation wells and three control operation wells, were entered in the Chemistry software. Next, formations were classified according to the type of production and the effects of their dissolution (quality); in the next step, buffers in intervals of one, three, five, seven and 10 km were created around wells and their layers were overlaid with geological maps. The t-test results showed that at 95%, at one, three, five and seven km from the wells, the impact of formations is significant on operation wells, but, at a distance of 10 km and with increasing distance, this effect was less and significant effect there is not in this respect, but, their total impact of non-quaternary formations increases on the wells. Also, the results from Boulian logic showed that that formation (Qt2) has the most spreading near the wells, including alluvial fans and young alluvial sediments which are the original location for feeding aquifers. But, by increasing the distance from the wells, the impact of non-quaternary formations like Cretaceous limestone and Batholith rocks (volcanic) that have the ability to produce water Brigade of sodium chloride and carbonate increases.
Haniyeh Asadi; Hamid Reza Moradi; Seyed Hamid Reza Sadeghi; Abdolrasoul Telvari
Abstract
The proper application of instantaneous unit hydrograph theory is very efficient for watershed with lack of rainfall data. Therefore, the present study has been conducted to evaluate the efficiency of Clark instantaneous unit hydrograph modelwith the help of geographical information system in regenerating ...
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The proper application of instantaneous unit hydrograph theory is very efficient for watershed with lack of rainfall data. Therefore, the present study has been conducted to evaluate the efficiency of Clark instantaneous unit hydrograph modelwith the help of geographical information system in regenerating flood unit hydrograph in Kasilian watershed in Mazandaran province. The comparative evaluation is conducted between the 3h-unit hydrographs simulated using Clark model and the one obtained from averaging the observed ones. This comparison is made with the help of statistical criteria viz. relative error, root mean square of error, coefficient of efficiency and bias. It verified high level of compatibility between two unit hydrographs using the Clark model and the hydrograph obtained by averaging the observed data.
Hossein Rastgar; Mehdi Habibi
Abstract
Sedimentation is one of the most important problems in watershed management. The characteristics of geological formations are the most basic factors which have an important role in sediment yield. There are several methods for sediment estimation, but sediment transport equations and formulas have been ...
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Sedimentation is one of the most important problems in watershed management. The characteristics of geological formations are the most basic factors which have an important role in sediment yield. There are several methods for sediment estimation, but sediment transport equations and formulas have been developed for special conditions which may not represent all conditions. Therefore to find out which method is suitable for a specific river, it is required to compare each method with the measured data. The purpose of this research is to evaluate efficiency of different methods of sediment discharge estimation in Jagin River at Panhan hydrometric station. The methods of modified Einstein, Engelund-Hansen, Yang, Habibi and Van Rijn are used in this investigation. The required data was collected from Water Regional Organization of Hormozgan Province. The sediment yield is estimated based on concentration of collected samples of floodwater. Then, the collected data were checked and corrected. The conclusion shows that the modified Einstein method is the most suitable method for sediment estimation in the study area.
Farzaneh Ghaemizadeh; Safar Marofi; Amin Toranjian; Alireza Ildoromi; Abbas Maleki
Abstract
In many regions especially dry areas such as Iran, groundwater resources are the main sources of drinking and agricultural water. In areas where natural supply and discharge of aquifer are not balanced, the water table will be dropped and the quality and quantity of aquifer water will be affected. The ...
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In many regions especially dry areas such as Iran, groundwater resources are the main sources of drinking and agricultural water. In areas where natural supply and discharge of aquifer are not balanced, the water table will be dropped and the quality and quantity of aquifer water will be affected. The aims of present study, was to use decision support tools to provide appropriate management method for artificial recharge of Hamedan-Bahar’s aquifer, using Boolean and Fuzzy pattern in GIS environment. Also, to provide a more economical solution, the possibility of using industrial wastewater treatment in the area, has been investigated. For this purpose, seven geographical information layers including slope, land use, surface infiltration, aquifer depth, aquifer quality, net feeding and transfer capability were interpolated. The resulted output maps showed that according to Boolean pattern 2.34 percent of the lands (equivalent to 10.95 km2 of the aquifer) are located in the central and eastern areas and according to fuzzy pattern 9.44 percent of the lands (equivalent to 44.22 km2 of the aquifer) which are scattered distributed, rated very good in terms of artificial recharge of Hamedan-Bahar aquifer. Also, the results showed that the Bu-Ali industrial estate water treatment plan outlet can be used to recharge the aquifer.
Majid Mahmoodabadi; Samira Zamani; Najme Yazdanpanah
Abstract
Interrill erosion is one of the most important types of erosion in agricultural lands, causing organic carbon (OC) loss from the soil surface. However, soil OC deficiency is a challenge facing agricultural production in most arid and semi-arid regions of Iran. In these regions, rainfall may be associated ...
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Interrill erosion is one of the most important types of erosion in agricultural lands, causing organic carbon (OC) loss from the soil surface. However, soil OC deficiency is a challenge facing agricultural production in most arid and semi-arid regions of Iran. In these regions, rainfall may be associated with high-speed winds that may remove large amounts of soil and OC. Therefore, the present study was carried out to investigate the role of wind and rain as erosive factors on the soil and OC losses and sediment enrichment during erosion events in some contrasting soils. For this purpose, using a simultaneous wind and rain simulator, combinations of three rain intensities (20, 40 and 60 mm h-1) and four wind speeds (0, 6, 9 and 12 m s-1) were introduced on three soils (sandy, sandy loam, and loam), each at three replicates. The results showed that the OC loss from the soils changed from 0.04 to 4.04 mg m-1 s-1. Synergistic interaction between rain and wind on OC loss was detected. In addition, a threshold limit (9 m s-1) was observed for wind velocity, above which soil and OC losses increased sharply. On the other hand, with increasing soil loss, the OC loss from each soil increased linearly. The contribution of OC loss in the total soil loss for sandy, sandy loam and loam soils was 0.36, 0.17 and 2.19%, respectively. Moreover, the enrichment ratio of OC in the sediments of soils was 8.2, 1.01 and 12.2, respectively. Based on the findings of this study, the wind speed reduction is recommended in agricultural lands, especially in windy areas to control the losses of OC due to interrill erosion.
Seyed Ahmad Hosseini
Abstract
Sediment dams are built with multi-purpose goals including flood control, erosion, sedimentation and aquifer feeding. These dams, with the aim of controlling the sediment from transferring part of it to the reservoirs of the dams in the downstream, and by causing a delay in the surface runoff, they control ...
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Sediment dams are built with multi-purpose goals including flood control, erosion, sedimentation and aquifer feeding. These dams, with the aim of controlling the sediment from transferring part of it to the reservoirs of the dams in the downstream, and by causing a delay in the surface runoff, they control a part of the flood and feed the aquifer of the area. Improper design or lack of optimal implementation of these structures causes the reduction of useful life and sometimes premature destruction of these structures. Evaluating the function and technical performance of such plans with the aim of improving and managing the system is of special importance. For this reason, in this article, a number of sediment dams implemented in Abdanan City of Ilam Province were investigated and evaluated. This research was conducted in the form of hydraulic simulation and comparison of the current situation with the conditions before the implementation of the project, in a section of the waterway about seven kilometers long. It should be mentioned that six stone and mortar dams have been built during the last decade. The results of the hydraulic simulation of the flooding of waterways and constructed structures showed that, based on the discharge with a return period of 100 years, the average overflow width of the construction dams is about 25% larger than the required value and the length of the stilling basin is about 40% less than the required value. In general, in all construction dams, the length of the stilling pond is not chosen correctly, so that the short length of the stilling pond has caused the hydraulic jump to leave the pond or to form at its end. Due to the high flow speed in the area of the hydraulic jump, erosion and destruction in the end zone of the calm pond has intensified, which has been extended to the upstream side and the main structure of the sediment dam. Based on the hydraulic simulation of the flood and the relative comparison of the results in the conditions before and after the construction of the dams, it was found that the constructed dams have a positive effect on the parameters of flow speed, flow strength and flow shear stress, which are all factors that aggravate erosion in the waterway. So that for discharge with a return period of 25 years, the speed, power and shear stress parameters of the flow have decreased by 23, 29 and 27%, respectively, during the research period. Therefore, the average reduction of these parameters locally and at the construction site of the six dams was estimated as 73, 85 and 82%, respectively. In general, according to the field visits and investigations, the implementation of the plan has been effective in controlling floods and sediments, and in case of annual protection and repair, its effects will be doubled.
Seyed Hamidreza Sadeghi; Raoof Mostafazadeh; Amir Sadoddin
Abstract
Assessment of suspended sedimentgraph (SG) and rating loops are important tools for analyzing the behavior of watersheds and successful implementation of watershed management measures in reducing sediment. However, the development and analysis of SGs and rating loops and influencing factors need more ...
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Assessment of suspended sedimentgraph (SG) and rating loops are important tools for analyzing the behavior of watersheds and successful implementation of watershed management measures in reducing sediment. However, the development and analysis of SGs and rating loops and influencing factors need more attention in watershed-scale. Therefore, the present study aimed to conduct the analysis of 13 observed and simulated sedimentgraphs (SGs) during October 2011 and November 2012, in Galaz-Chai Watershed with an area of 103km2 located in West-Azarbaijan Province, Iran. Towards this attempt, the SG of observed events was derived using instantaneous unit sediment graph (IUSG) concept, and the effects of different land uses were investigated. Also, the variation and patterns of the simulated sedimentgraphs (SGs) and rating loops were plotted and interpreted with the respective land use types. Based on the results, an early peak occurred in SGs with respect to the observed hydrograph peak rates and consequently had clock-wise pattern. Increase in falling limb of hydrograph could be attributed to the participation of sediment production from agricultural land in watershed upstream. The model predicted SGs with good accuracy according to the Nash-Sutcliffe criterion (70%). Analysis of results indicated that the type and distribution pattern of different land uses had significant effect on the shape of SGs and sediment rating loops.
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.
Saeed Najafi; Habib Nazarnejad; Hedieh Mohammadnezhad
Abstract
Since most of soil erosion studies in the watersheds are conducted by consultant and executive companies (as contractors) using the semi-quantitative MPSIAC model under the supervision of provincial natural resources and watershed administrations (as employers), so in this study, the results and findings ...
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Since most of soil erosion studies in the watersheds are conducted by consultant and executive companies (as contractors) using the semi-quantitative MPSIAC model under the supervision of provincial natural resources and watershed administrations (as employers), so in this study, the results and findings of the aforesaid studies in West Azerbaijan Province were considered. Analysis of the studies showed that in the last three decades a total of 76 watersheds of the province with an approximate area of 4100 km2 have been studied in terms of soil erosion and sediment yield states using the MPSIAC Model. Estimated mean annual soil erosion was 13.95, 16.30, and 15.59 t.ha−1.yr−1 for northern, central, and southern sections, respectively. Meanwhile, based on the model, the mean sediment yield of mentioned sections has been calculated equal to 5.39, 5.64, and 6.09 t.ha−1.yr−1. Nevertheless, a detailed investigation based on the resistance of different lithology units to erosion in the studied watersheds, as well as land use and vegetation cover as the two most important factors of the MPSIAC Model showed less reliability of the reported results. It seems one of most important reasons for such unreliable results refers to one of the most important weaknesses of the MPSIAC model which estimation of the soil erosion is depended on the estimated amounts of sediment yields and sediment delivery ratio. According to our findings, it can be concluded and suggested that the Forests, Rangelands, and Watershed Management Organization should replace the MPSIAC Model, with USLE family models, especially RUSLE, at least in estimating the soil erosion, in the services description of consultant and executive companies. Implementation of this change should also be taken seriously by the provincial natural resources and watershed management administrations.
Mohammad Gheitury; Mosayeb Heshmati; Mohammad Roughani
Abstract
Water resources scarcity is the negative impact of climate change, which is more severe in arid and semi-arid regions, including Iran. However, harvesting water through micro-catchment is one of the possible issues for combating this problem. This research was conducted in Kaboodeh-Olya Village to compare ...
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Water resources scarcity is the negative impact of climate change, which is more severe in arid and semi-arid regions, including Iran. However, harvesting water through micro-catchment is one of the possible issues for combating this problem. This research was conducted in Kaboodeh-Olya Village to compare the effects of three different micro catchment systems on runoff harvesting and increasing soil moisture. The experimental plots were constructed at a 20% hill slope in northern direction. Research was carried out in randomized experimental block with tree replications. Micro catchments were constructed in rhomboid-shape (1.7×1.7 m) and treatments included plastic with pebble pavement (PPP), compacted surface soil with crop residue (CSCR) and control plot (CP) which was a natural surface soil. The harvested runoff from each plot was stored in a container with 100 litter capacity at the downward. The valium of overland flow was measured after each rainfall occurrence. Results demonstrated that harvested runoff rates through PPP, CSCR and CP were 88, 44 and 16 percent, respectively indicating significant effects (p<0.05) of both PPP and CSCR on runoff harvesting. Furthermore, the effective rainfall for triggering runoff at the PPP, CSCR and CP were 0.8, 1.5 and 3.4 mm that significantly was lower in PPP. Consequently, in limited CSCR building, the SSS can be used for maximum runoff harvesting and soil moisture storage.
