Mohammad Ali Zanganeh Asadi; Mahnaz Naemi tabar; Mokhtar karami
Abstract
Desertification is a problem that is currently affecting many countries in the world, including Iran. This problem is seen not only in arid and semi-arid areas, but also parts of semi-humid areas. The purpose of this study is to investigate and zoning the intensity of desertification using the modified ...
Read More
Desertification is a problem that is currently affecting many countries in the world, including Iran. This problem is seen not only in arid and semi-arid areas, but also parts of semi-humid areas. The purpose of this study is to investigate and zoning the intensity of desertification using the modified Medalus Model and hierarchical clustering method in the Baqous Plain of Sabzevar. For this purpose, effective criteria in desertification including climate, vegetation, soil, erosion, and selection management, and the geometric mean of the indicators were calculated. Data layers indicators related to each criterion were prepared using the GIS system. This information was scored based on the Medalus method and from the geometric mean of the indicators of each criterion, the final map of the status of each criterion was prepared and from the geometric mean of the criteria, the current map of the desertification of the region was prepared. Results showed that the criteria of vegetation, climate, and erosion were more effective than other factors in desertification of the region and high sensitivity and critical type was matched with the poverty of vegetation and the dryness of the climate, and work units 1 and 2 have the largest area of desertification types with high intensity. The results also showed that 21% of the study area is in the high sensitivity zone, 28% in the high and critical sensitivity zone, 17% in the low sensitivity zone, 28% in the low and critical sensitivity zone, and 6% in low sensitivity zone to erosion. 55.6% of the results of modified Modalus Model were obtained by significant clustering methods. According to the spatial distribution map of desertification intensity extracted from the model, it can be used as an auxiliary tool against desertification and prevent excessive destruction of the region in the future.
Ali Khodaie; Rahman Zandi
Abstract
Occurrence of numerous floods in different regions of the country has always caused a lot of damages in various fields. Therefore, it seems necessary to prepare and compile a comprehensive plan in the field of flood control. The study area is influenced by the Mediterranean climate and within the radius ...
Read More
Occurrence of numerous floods in different regions of the country has always caused a lot of damages in various fields. Therefore, it seems necessary to prepare and compile a comprehensive plan in the field of flood control. The study area is influenced by the Mediterranean climate and within the radius of the Caspian and Caucasian climates. Due to the high altitude differences, it has a variety of climates and high variability in rainfall, and known as one of the areas exposed to destructive floods. The purpose of this study is to identify flood prone areas based on multi-criteria decision making and neural network model in Khodaafarin Watershed. For this purpose, according to the factors affecting the occurrence of floods, the information layers of the region including Curve Number (CN), Gravilius coefficient, runoff height, precipitation, distance from waterway, soil retention, waterways, slope, drainage density, geology and vegetation, according to the study of maps, reports, satellite images and field surveys. In order to weight the criteria in the present study, network analysis method (ANP) and Super Decisions software were used. The factor of runoff height with the amount of 0.241, slope with the amount of 0.207 and precipitation with the weight of 0.169 were the most important in relation to flood occurrence. Finally, by combining these layers according to their weight in the GIS environment, a flood risk zoning map was extracted in five classes. The results also showed that, 43 square kilometers (3% of the area) of the watershed is in the very high flood risk class and 288 square kilometers (18% of the area) in the high flood risk calss. More than 21% of the area is among the areas with high and very high flood potential. Therefore, it seems that the need for surface water management in the region in order to prevent floods and the proper use of water in the region is necessary.
Ali Khodaie; Abbas Pahlavani; Zahra Ghelichipour; rahman zandi
Abstract
The protection and management of each user in different areas should be based on ecological conditions, which can be achieved by assessing the ecological potential in each area. Assessing ecological potential means examining the potential power of the land and determining its natural use by humans. The ...
Read More
The protection and management of each user in different areas should be based on ecological conditions, which can be achieved by assessing the ecological potential in each area. Assessing ecological potential means examining the potential power of the land and determining its natural use by humans. The main purpose of this study is to identify the ecological potential in Khodaafarin City with an area of 161,607 ha, using the multi-criteria assessment method, the common land management model of Dr. Makhdoom and using GIS. In this study, after identifying ecological resources (sustainable and unstable), the resources were analyzed and summarized. Then, in the software environment (ArcGIS 10.6), the information layers were combined and then the maps were evaluated. Finally, according to the existing values, the potential strengths and bottlenecks of the region were estimated and the permitted uses were prioritized in the region. As a result, after combining the necessary maps and correcting them, the environmental capacities and ecological potential of the region were estimated as area (percentage) in Khodaafarin City. According to the objectives of the research, areas prone to segregation of aquaculture-agriculture (2.65), aquaculture-rangeland management (0.14), aquaculture-urban and rural development (0.2), aquaculture-extensive tourism (0.049), conservation-extensive tourism (0.45), conservation-forestry (0.12), centralized tourism-forestry (0.021), aquaculture (6.34), extensive tourism (12.61), centralized tourism (2.64), rangeland management (33.1), agriculture (7.51), conservation (13.57), urban, rural and industrial development (1.8), forestry (18.8) were zoned and identified. The results also showed that the highest potential is related to the rangeland management with an area of 61567.55 ha of which less than 50% (30457 ha) is consistent with the current conditions.
Hersh Entezami; Sayed Kazem Alavipanah; Hamidreza Matinfar; Ali Darvishi; Kamran Chapi
Abstract
The importance of snow and its water equivalent in water resources supply has caused many studies and researches to measure snow characteristics and runoff. Conducted in the Saqqez Watershed, this research attempted to estimate snow–induced runoff in a mountainous area and the SRM Model was ...
Read More
The importance of snow and its water equivalent in water resources supply has caused many studies and researches to measure snow characteristics and runoff. Conducted in the Saqqez Watershed, this research attempted to estimate snow–induced runoff in a mountainous area and the SRM Model was selected to simulate daily runoff from snow-melt. Based on the data and variables for four consecutive years of 2006 to 2009 collected and snowmelt runoff was estimated. MODIS satellite images were used to calculate the snow coverage area. After segregating the snow coverage from the images, the daily snow area was calculated using GIS, and along with the other variables, imported into the model. For better evaluation of efficiency of the model, the model was calibrated and validated. The process of calibration was led to the best estimate for each parameter. To evaluate the accuracy of model and comparing results with field data Nash-Sutcliffe coefficient and the percentage difference were used. The results of the Nash-Sutcliffe coefficient were between 0.90 to 0.94 and the differences in the volume were 6.8 to 7.2 percent, which indicates the high-performance of modeling.
Mehdi Khalajzadeh; Gorban Vahabzadeh; Sadat Feiznia; Aliakbar Nazarisamani; Seyed Ramzan Mousavi
Abstract
Identification of hydrogeomorphic processes such as normal flood, debris flood and debris flow on alluvial fan (at the outlet of the watershed) is essential due to the type of sedimentary regime and various hazards. In recent years, the lack of field information has led to the need to use models based ...
Read More
Identification of hydrogeomorphic processes such as normal flood, debris flood and debris flow on alluvial fan (at the outlet of the watershed) is essential due to the type of sedimentary regime and various hazards. In recent years, the lack of field information has led to the need to use models based on basic watershed information. The aim of this study is to develop a practical method for predicting the occurrence of various types of flood flow, using physical and geomorphological characteristics of watersheds. In this study, a descriptive-analytical method and some of tools, such as aerial photographs, satellite images, topographic maps were used. First, by descriptive method, field evaluation of sediments of various types of flood currents was carried out on July 19, 2015 in 70 sub-watersheds of in Karaj Dam Watershed. Results showed that out of 70 sub-basins, 30 sub-basins, debris flow, 16 sub-basin debris flood and 24 sub-basins were normal floods. Then, in the analytical method, 32 geomorphometric features of watersheds by 25-meter spatial digital model (DEM) and five geomorphological features of sub-watersheds by mass movement maps were extracted and then were transferred to the SPSS statistical program to determine the relationship with the type of flood flow. The results of ANOVA and Bonferroni multiple comparisons showed that four morphometric factors “main channel length, basin perimeter, mean basin width and basin length” were identified in differentiation of flood flow types. To achieve the two appropriate key parameters and threshold values, four variable pairwise were copaird by pair in six triple scatter plots. The results showed that “The main channel length (Lm) and the mean basin width (Wb)” has the least total errors of the observation streams, were selected as the most appropriate factors for predicting flood flows. In long basins with Lm>4 km, normal flooding occurs, and in short basins with Lm1 km, floods occur, and if Wb
mohammad ekrami; Rasool Mahdavi Najaf abadi; Marzieh Rezai; hassan vagharfard; Jalal Barkhordari
Abstract
In recent decades, among natural disasters, the frequency of agricultural drought has been higher than other natural disasters. The best way to management of agricultural drought was to management drought-stricken society. The purpose of this study was to assess the vulnerability and spatial analysis ...
Read More
In recent decades, among natural disasters, the frequency of agricultural drought has been higher than other natural disasters. The best way to management of agricultural drought was to management drought-stricken society. The purpose of this study was to assess the vulnerability and spatial analysis of drought in Pishkuh watershed in Yazd province. the effective parameters in the vulnerability of agricultural drought in the region became information layers, and after weighting the layers in terms of the importance of agricultural drought vulnerability in the framework of multi-criteria decision making (MCDM) Agricultural drought in the study area was prepared. In order to control, monitoring and evaluation the final map, field studies of the study area were also used. The results showed that the highest weight of the effective parameters in drought vulnerability was related to the precipitation parameter, the value of which is equal to 0.31, and the lowest weight was related to the slope parameter with a value of 0.05. According to the obtained results, the most vulnerable agricultural droughts were related to Sanich, Darashir, Darasir, Eshkaft, Morok, etc. Geomorphologically, these areas were considered to be high and mountainous, more severe than plain areas due to the low depth of sediments, coarse-grained soil texture and aquatic resources (Qanats), mainly their vulnerability to drought, and In terms of time, they suffer more quickly, in other words, they suffer a lot of damage in the short term. While areas such as Islamia, Nasrabad, Mazrea Akhund, Hemmatabad , etc. were in a lower degree of agricultural drought damage. The results indicate that the degree of damage to agricultural drought estimated in the final map is in line with the findings of field studies. Therefore, the map of agricultural drought vulnerability has acceptable and desirable accuracy.
Roya Jafari; Mohsen Hosseinalizadeh; Hasan Rezaii Moghadam
Abstract
Accurate estimation of a watershed response to rainfall events plays an important role in its soil and water resources management as well as civil works design within watersheds and over or around its downstream rivers. Nowadays, due to improvement in our knowledge and understanding from watershed systems ...
Read More
Accurate estimation of a watershed response to rainfall events plays an important role in its soil and water resources management as well as civil works design within watersheds and over or around its downstream rivers. Nowadays, due to improvement in our knowledge and understanding from watershed systems and enhancement in hardware and software technology as well as facilitation in learning and application of these technologies, researchers prefer to design and apply their required models themselves according to their aims and availability of data. The aim of this research is to develop a spatio- temporally distributed model within PCRaster GIS and programming environment to achieve a better representation of watershed processes at a small scale agricultural micro-watershed. In this study, based on the available local data, an event based rainfall – runoff hydrological simulation model was developed within PCRaster GIS and programming software and its performance was evaluated using observed data from a 27.6 ha agricultural micro-watershed discharging to the Shahrak – Behzisti residential area in the Gorgan city. This is a tightly coupled GIS model. During the research period, only two rainfall events leading to runoff generation occurred on 2/11/2014 and 16/9/2015 which were, respectively, used for calibration and validation of the model. Statistical comparison of the simulated and observed hydrographs of the rainfall - runoff events on 2/11/2014 and 16/9/2015 showed the correlation coefficients of of 0.69 and 0.65 and Nash-Sutcliffe criteria of 0.5 and 0.51, respectively. The results indicate that the developed model has a good performance at simulating rainfall-runoff processes during events.
Soghra Malekpurlarki; Zohre Khorsandi kouhanstani; Mohammad Faraji
Abstract
Conservation and utilization of water resources are principles of sustainable development of each country. Surface waters or rivers are one of the most important water resources which have important role in supplying water demands in different sectors such as agriculture, industry, drinking water and ...
Read More
Conservation and utilization of water resources are principles of sustainable development of each country. Surface waters or rivers are one of the most important water resources which have important role in supplying water demands in different sectors such as agriculture, industry, drinking water and energy. Shavoor River which is one of the effective rivers in Shoosh City is important due to its quality in water urban and agricultural usages. Land use and its changes have important effects on river water quality. In this research, the effect of land use change is investigated in water quality of Shavoor River in 1985-2015. For this reason, land use maps of 1985 and 2015 were prepared by satellite imageries and land use changes were investigated. Results showed an increase in residential and agricultural lands and a reduction in rangelands and forests. Also, the changing trend of water quality factors in Shavoor River was studied with Mann-Kendall test and graphs. Results demonstrated that the changes overall trend of Hco3, Cl, TDS, EC, Ca, Mg and So4 were increasing in the period. According to meaningful changes of parameters, it can be concluded that the increase in residential and agricultural lands and reduction in rangelands and forests cause the water quality of Shavoor River in the study period.
Elham Afrough; Masoud Masoudi; Seyed Yousef Erfanifard
Abstract
Destroying natural resources and environment is one of the most important problems in different regions around the world, especially in arid zones. So that extent areas of these zones are being destroyed in extensive spectrum of these destruction processes. For this reason, evaluating and providing vulnerability ...
Read More
Destroying natural resources and environment is one of the most important problems in different regions around the world, especially in arid zones. So that extent areas of these zones are being destroyed in extensive spectrum of these destruction processes. For this reason, evaluating and providing vulnerability map of vegetation degradation in our country can considerably help the management and executive planning. In the present research, the criteria used in a new model called NIDLTS are proposed for evaluating the vegetation degradation. These criteria are natural index(N), human indirect index (I), human direct index (D), livestock pressure (L), trend of degradation (T) and state indicators (S). In order to estimate each criterion, a number of risk index were used. Natural indices studied in this research were climate change, draught, climate and suitability of lands. Human indices which were studied are population density, population growth, governmental expenses from executive works and researches, changing natural resources land to agricultural lands, percentage of unemployment, percentage of illiteracy. The indices of studied status are percentage of crown cover, production of the present biomass and production of the present biomass to the potential. Hazard index related to each destruction group were classified in to five classes of hazard intensity with numerical values in order to be analyzed in GIS. Then, the weight of each index and each main group of NIDLTS framework were calculated by Hierarchy Analysis Process (AHP); so that giving priority was done through investigating their share and effects in the vegetation decline. Finally, the vulnerability map of vegetation risk was generated through overlaying all the layers for each criterion in GIS. Results showed that among the human factors, the changing land use from natural resources to agriculture is the most important factor, whereas among the natural factors, drought is the most important factor in the study area. Also, among all the criteria, natural index has the highest effect and the trend of degradation of natural resources lands has the lowest effect in the vegetation degradation during the time. The final hazard map showed that the most widespread hazard class is moderate, followed by no-hazard in the region. It seems logical that the proposed model of NIDLTS for assessing the hazard of vegetation degradation can provide a more accurate estimation of vegetation degradation in a region with taking into consideration of the ecological, anthropogenic and hazard trend in comparison with some other evaluations that only consider the current state of vegetation degradation.
Raziyeh Motamedi; Mahmood Azari; Reza Monsefi
Abstract
Landscape is one of the main factors influencing hydrological processes of the watershed. Changes in structure and spatial pattern of land use play important role in surface runoff and sediment yield. Determining the relationship between landscape patterns and hydrological processes can be used as an ...
Read More
Landscape is one of the main factors influencing hydrological processes of the watershed. Changes in structure and spatial pattern of land use play important role in surface runoff and sediment yield. Determining the relationship between landscape patterns and hydrological processes can be used as an indicator of watershed soil erosion and sediment yield. Therefore, due to the problems in field measurement of sediment yield, its estimation using landscape properties and land use pattern is an appropriate alternative for current estimation methods. The purpose of this research is to determine the relationship between watershed sediment yield and landscape metrics in the selected sub-watersheds of Golestan Province. To this end, suspended sediment concentration data for all hydrometric stations of the studied province were obtained from the relevant resources and appropriate sub-watersheds were selected. Then, using the land use map of Golestan Province, 15 landscape metrics related to sediment yield were determined for different land uses by Fragstats 4.2 software. In order to determine the relationship between watershed sediment yield and landscape metrics, a partial least squares regression was used which combines the methods of principal component analysis and multiple linear regression. The relative importance of landscape metrics was determined through examining the values of Variable Importance for the Projection (VIP) and Regression Coefficients (RCs). The results of this study indicated that the watershed sediment yield is densely associated with land use patterns. The main indices in reducing sediment yield were the Largest Patch Index (LPI), the average of the nearest neighbor distance (ENN-MN) and the average of perimeter-area ratio (PARA –MN) with values of VIPs of 1.296, 1.184 and 1.747, and regression coefficients of -0.014, -0.039, and -0.002, respectively. The main indices in incrising sediment yield were Landscape Shape Index (LSI) and mean patch size (AREA-MN) with regression coefficients of 0.020 and 0.017, respectively. The landscape characteristics in watersheds could account for as much as 71% of the variation in sediment yield of watershed. The results of study showed that the landscape characteristics can be used for watershed sediment yield modeling.
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 ...
Read More
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.
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 ...
Read More
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.
Hassan Vagharfard; Hassan Moghim
Abstract
Flood spreading is an effective way to increase the groundwater level, rectify the critical conditions of groundwater, and prevent flooding at Naeim-Abad, Fars Province. The most important step in the successful implementation of artificial recharge is the selection of recharge areas in the studied region. ...
Read More
Flood spreading is an effective way to increase the groundwater level, rectify the critical conditions of groundwater, and prevent flooding at Naeim-Abad, Fars Province. The most important step in the successful implementation of artificial recharge is the selection of recharge areas in the studied region. In this research, the GIS technique and Analytical Hierarchical Process (AHP) method have been used. We considered nine factors–land, slope, and distance from the road, altitude, thickness of the alluvium, distance from the stream, surface permeability, land use, and fault for analysis in this research. Each layer was prioritized using the AHP method and the different layers were integrated. Expert Choice software was used to prioritize nine considered factors. The results showed that 3.6% of the Naeim-Abad area was suitable for flood spreading based on the AHP method and GIS technique. In this research, hydrologic factors with a weight of 0.687 had the most impact among the main criteria for locating areas prone to flood spreading. Among the sub-criteria of this criterion, surface permeability with a weight of 0.558 had the greatest influence. In addition, the sub criterion of land use was weighted equal to 0.701, which had the highest weight among the sub criteria. The lowest weight among the sub criteria was attributed to the distance from the road with a weight of 0.106, which indicated the least influence on locating suitable areas for flood spreading.
Narges Ghasemiamin; Nasim Arman; Hossein Zeinivand
Abstract
Land use and its fluctuations is one of the most important factors that affects on the natural cycle in the ecosystem. Land use changes cause change in watershed hydrological cycles, water balance between precipitation, evaporation, infiltration and runoff response. Understanding the relationship between ...
Read More
Land use and its fluctuations is one of the most important factors that affects on the natural cycle in the ecosystem. Land use changes cause change in watershed hydrological cycles, water balance between precipitation, evaporation, infiltration and runoff response. Understanding the relationship between land use changes and its factors and secondary effects on the hydrological regime provides the necessary information for planning of land use and sustainable management of natural resources. At first, land use maps related to years of 2000 and 2014 were prepared, then CLUE-s model was applied to simulate land use map of 2025. For simulating runoff, WetSpa model was employed to simulate daily runoff with land use maps related to years of 2000, 2014 and 2025. According to the results, the Nash-Sutcliffe evaluation criterion was calculated 68.26 % and 66.75 % for the calibration and validation periods, respectively. In addition, model Aggregate Measure (AM) was calculated 64 % and 54.15 % for the calibration and validation periods, respectively. Land use maps comparison showed, the main land use changes in Nojian Watershed was the conversion of forest and rangeland areas to agricultural lands .As a result of these changes the annual runoff volume, peak discharge, mean daily discharge increased to 16.20, 11.35 and 9.15 percent, respectively. Results of statistical analysis using paired t-test showed that land use change has effect on discharges in the study area at the level of 1%.
Mohammad Hassanzadeh Nafooti; Ehsan Emami Maybodi
Abstract
This research aims to study temporal and spatial variations of groundwater quality of Marvast Plain to manage these recourses. For this purpose, total anion and cation, a percentage of sodium, Ca, Cl, EC, HCO3, K, Mg, Na, pH, SRA, So4, TH parameters were prepared and a statistical period of 14 years ...
Read More
This research aims to study temporal and spatial variations of groundwater quality of Marvast Plain to manage these recourses. For this purpose, total anion and cation, a percentage of sodium, Ca, Cl, EC, HCO3, K, Mg, Na, pH, SRA, So4, TH parameters were prepared and a statistical period of 14 years (1377_1390) was selected using the evaluation of incomplete data. Semivariograms and cross semivariograms were potted to perform geostatistcal methods and the best model was selected with regard to more R2, less RSS and a strong spatial structure, and an exponential model was fitted for most parameters. Then, interpolation methods, such as Radial Basis Function (RBF), Inverse Distance Weighting with powers of 1 and 2 (IDW), Kriging and coKriging were used. The most accurate method was selected for parameters using cross validation method and error estimation indexes such as Mean Absolute Error (MAE), Mean Bias Error (MBE) and Root Mean Square Error (RMSE). The results showed that coKriging is the best method for estimating most parameters (total anion and cation, EC, Cl, Ca, K, Mg, Na, TH). Kriging is defined as the most suitable method for estimating SRA, So4 and pH, and RBF and IDW with power 1 are the most fitted methods for a percentage of Sodium and HCO3, respectively. The results showed that the density of most parameters increases from west to east and south to north of the study area. Also, decreasing underground water quality is observed over the time.
Mahnaz Babaei; Seyed Zeynalabedin Hosseini; Aliakbar Nazari Samani; Seyed Ali Almodaresi
Abstract
Recently soil erosion and sediment yield has become one of the most important problems of the environment. Soil erosion risk assessment and sediment yield are first steps to confront with this problem. In this regard, various models and methods proposed. What is certain, first of all must be verified ...
Read More
Recently soil erosion and sediment yield has become one of the most important problems of the environment. Soil erosion risk assessment and sediment yield are first steps to confront with this problem. In this regard, various models and methods proposed. What is certain, first of all must be verified the functionality of these models. The present study is carried out to KanSoleghan watershed in order to estimate the soil erosion risk and sediment yield. RUSLE 3D was used in geographical information system platform. Rainfall Erosivity (R), were obtained from monthly and annual data and IDW techniques, Soil Erodibility (K) were obtained from soil data and regin map, Land cover Management (C) using remote sensing techniques (with use of NDVI), LS using digital elevation model, Soil Conservation Practice with using slope percent map. Eventually based on RUSLE 3D model combining these factors together, annual average risk of soil erosion was obtained 22.20 t.ha-1.y to estimate the sediment delivery ratio was used several models, accordingly, the estimated annual sediment yield was overestimated in all models. Sedimentation basin was calculated using statistics gauging stations sooleghan (1.82 tons per hectare per year). Our study indicated that LS factors of the RUSLE 3D model (r2=0.68) were the most effective factors controlling soil erosion in the region. In general, it can be said that the reliability of the used data and used methods is too low and too many uncertainses exist for areliable calculation of soil loss amounts in kan soleghan watershed using the RUSLE 3D Model.
Behrouz Mohseni; Hadi Razzaghian; Abdollah Darzi-Naftchali; Esmaeel Nikzad
Abstract
Runoff as one of the water balance components of a basin, is of great importance in watershed and water resources management. Suitable estimation of runoff is requires to determination of runoff coefficient. In this study, runoff coefficient was estimated for return periods of 25 and 50 years using rational, ...
Read More
Runoff as one of the water balance components of a basin, is of great importance in watershed and water resources management. Suitable estimation of runoff is requires to determination of runoff coefficient. In this study, runoff coefficient was estimated for return periods of 25 and 50 years using rational, SCS and Cypress-Creek methods for basins up to 50 square kilometers. GIS software was used to overlay layers and basin analysis. Chow, s table was used to correspondence different methods. Due to the lack of compliance with Chow, s table and estimating lower runoff coefficients than reality in most of the study area, Rational Method did not provide suitable results. Cypress-Creek method was also effective in some basins due to it similarity with the SCS method. Average equivalent runoff coefficient of C25=0.37 and C50=0.41 demonstrated high accuracy of SCS method compared with two other methods. According to the soil conservation service method, minimum and maximum runoff coefficients of 25- year return period were related to Chalakrud 1 (0.06) and Safarood 4 (0.61) watersheds, respectively. Also, the minimum and maximum runoff coefficients of 50- year return were 0.1 (for Chalakrud 1) and 0.65 (for Safarood 4), respectively. According to the results of three methods, the lowest runoff coefficients were obtained for watersheds with the highest area and the lowest rainfall intensity.
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 ...
Read More
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.
Somayeh Jafari; Reza Bayat; Amirhossein Charkhabi; Nader Jalali; Fazel Iranmasnesh
Abstract
Sand dunes developed in 15 provinces with an area of 4.4 million hectares and 56 Citadel, are one of the most important geomorphological features in Iran. Sand and desert stabilization technical office studies, according to project results identify focal and present four regions including Ahvaz, Dasht-e-Azadegan, ...
Read More
Sand dunes developed in 15 provinces with an area of 4.4 million hectares and 56 Citadel, are one of the most important geomorphological features in Iran. Sand and desert stabilization technical office studies, according to project results identify focal and present four regions including Ahvaz, Dasht-e-Azadegan, Susa and the Omidiyeh in Khuzestan province. The mentioned area includes 279,505 hectares of land in Khuzestan. This study has used remote sensing technology, GIS techniques and analyzed effective recorded winds data. Toward were reviewed and analyzed the wind regime of the area for direction of source area using Windrose Diagrams. In this study, based on utilizing and composing of image processing techniques such as image enhancement, threshold, false color composition, filtering and analysis and results of wind data analysis, with other investigations is useful to find the source of sand dunes. The results from direction of source area confirm that source of sand dune located in NW to W, notice Windrose in Khuzestan. The source area are flood alluvial fan plain, alluvial fan, agriculture land, meandering rivers and sensitive formation to erosion including Aghajari formation and Bakhtiari formation that located in the in NW to W section.
Maryam Azinmehr; Abdolreza Bahremand; Atena Kabir
Abstract
The various types of land cover and land use have significant roles and impacts on runoff and flood; but how and to what extent is not clear and highly uncertain. The models are becoming more capable for flood prediction, landuse impacts on floods, and decision making in watershed management. The main ...
Read More
The various types of land cover and land use have significant roles and impacts on runoff and flood; but how and to what extent is not clear and highly uncertain. The models are becoming more capable for flood prediction, landuse impacts on floods, and decision making in watershed management. The main objective of this research is to assess the impacts of land use changes on flow hydrograph by means of distributed modeling and GIS. A grid-based spatially distributed hydrologic model, WetSpa, which has been developed at the Department of Hydrology and Hydraulic Engineering of VUB, is used in this research to fulfill the aim. The basic model inputs are a digital elevation model (DEM), land use and soil maps of the study area in GIS raster format, and hydrometeorological data. The model is applied to the Dinvar river basin (1717 km2), and its main tributaries. The Dinvar river located in Kermanshah, is one of the main tributaries of the Karkheh River. The model predicts the daily hydrographs with a good accuracy, 66% according to the Nash-Sutcliffe. For assessing the impact of landuse changes on floods, the calibrated model is applied for nine scenarios using the hourly data. The potential of Dinvar cachment, nine landuse change scenarios in GIS was determined and entered the calibrated model for simulation. changes in processes and hydrological parameters were investigated by comparing the output hydrograph of present landuse with simulation result of 9 scenarios. Results show that model simulation is acceptable as for the result of model.
Keivan Khorrami; Ghorban Vahab Zadeh; Karim Soleimani; Reza Talaei
Abstract
The use of groundwater is one of the ways to overcome the seasonal shortages of water.Underground dam that can be noted as one of the techniques to help the improvement of water resources management and increase the efficiency of these resources, is one of the water storage practices to use the groundwater. ...
Read More
The use of groundwater is one of the ways to overcome the seasonal shortages of water.Underground dam that can be noted as one of the techniques to help the improvement of water resources management and increase the efficiency of these resources, is one of the water storage practices to use the groundwater. . It is a simple method for the collection and storage of water in arid and semi-arid areas. In this study, selection of suitable areas of underground dam in Gharasou watershed is investigated. Many factors are influenced in determining the suitable areas of underground dam. In this research, physiography, geology, hydrology, hydrogeology and land use of the watershed were investigated and analyzed with the use of information, maps, reports, required data and geographic information system. Then, derived maps from different stages were combined and finally suitable areas and streams for construction of underground dam were mapped. Results showed that about 30 percent of Gharasou watershed is suitable for construction of underground dam.
Reza Bayat; Bagher Ghermez Cheshmeh; Hoseingholi Refahi
Abstract
The rate of soil erosion and sediment yield depends on different factors. Vegetation cover is more variable factor effecting occurrence of soil erosion in comparison to the other factors in a given watershed. The main purpose of this study was to investigate the role of canopy cover resulting from land ...
Read More
The rate of soil erosion and sediment yield depends on different factors. Vegetation cover is more variable factor effecting occurrence of soil erosion in comparison to the other factors in a given watershed. The main purpose of this study was to investigate the role of canopy cover resulting from land management on sediment yield. Taleghan watershed was selected as a study area due to the availability of sufficient data. Necessary information was provided for MPSIAC model and was made in GIS environment and all needed calculations were done for preparing sediment yield map. The result of the comparison of the calculated and the estimated sediment yield indicated similarity of them (i.e. 98.3% similarity). For impact assessment of vegetation cover effect on sediment control, canopy cover was changed in a range of ±5 to 25% percent with 5% interval in both good and bad conditions. The effect of these changes was applied to bare soil percentage as well. The related thematic maps were prepared and sediment yield was determined. The result showed that sediment yield varied because of changing canopy cover. The increase and decrease of canopy cover by 25%, affected the sediment yield to change by -29.6% and 26.8% respectively.
Hamid Reza Matinfar; Fereydoun Sarmadian; Seyed Kazem Alavipanah
Volume 2, Issue 4 , January 2011, , Pages 211-220
Abstract
Soil salinity is one of the main increasing problems of the world. In the recent years application of remote sensing and GIS techniques in order to assess saline soils is used because they bring about vast uniform coverage of ground phenomena in a short time. The images of LISS III sensor of the Indian ...
Read More
Soil salinity is one of the main increasing problems of the world. In the recent years application of remote sensing and GIS techniques in order to assess saline soils is used because they bring about vast uniform coverage of ground phenomena in a short time. The images of LISS III sensor of the Indian satellite (IRS) were used in this research. The Brightness index (BI) could discriminate highly saline soils from non –saline and the salinity index (SI) show high potential to separate very high, high and non- saline soils. Results of supervised classification without combination DEM and remote sensing data have overall accuracy of 76%, producer accuracy of 78% and user's accuracy of 82%. While in supervised classification combination of remotely sensed data and DEM have overall accuracy of 98.1% , producer accuracy of 98.28% and user's accuracy of 98.4% .The reason for low accuracy of the classification , before combination of remote sensing and topographic data , can be explained by highly moist saline soils spectral interference with non-saline soils (soil with 25 to 65% gravels) , but these two soils had different topographic condition with 200 meters elevation difference , thus , with combination of the DEM , this kind of area and other areas with similar conditions have been separated from each other.
Ali Mohammadi Torkashvand; Davood Nikkami; Mehrdad Esfandiari; Seyed Kazem Alavipanah
Volume 2, Issue 3 , October 2010, , Pages 150-160
Abstract
Rill erosion map is one of the basic maps in erosion and sediment studies and also watershed management programs. Some methodologies for preparing rill erosion map (1:250000) by using RS and GIS were compared in a research carried out in Kan-Sologhan and Jajrood sub-basins in North-west and North-east ...
Read More
Rill erosion map is one of the basic maps in erosion and sediment studies and also watershed management programs. Some methodologies for preparing rill erosion map (1:250000) by using RS and GIS were compared in a research carried out in Kan-Sologhan and Jajrood sub-basins in North-west and North-east Tehran, Iran. At the first phase, four working units' maps were prepared by integration of a) plant cover, geology and slope b) land use, geology and slope c) land use, rocks sensitivity to erosion and slope and d) land use, rocks sensitivity to erosion and land units’ layers in Kan-Sologhan basin. For comparing the efficiency of four working units’ maps, 53 ground control points were investigated. Results showed that map "d" was better than "a", "b" and "c" in providing rill erosion regarding economic and executive considerations. At the second stage, map "d" was compared with three maps of e) land units f) rocks sensitivity to erosion and g) satellite image photomorphic units (ETM+ images) in a broader basin of Jajroud. Rill erosion intensities in 314 ground control points were controlled and ground truth rill erosion map was prepared. Rill erosion map was crossed with different working unit maps where results showed that the highest accuracy is related to the images interpretation (81.0% accuracy). Accuracy was 78.4, 66.8 and 59.9 percent for methods of "d", "e" and "f", respectively. Root Mean Squared Error was the highest for map "f" and the least for integrated layers method (map "d"). The greatest precision is related to image interpretation and the images interpretation method is better than other methods in preparation of rill erosion map.
Reza Sokouti Oskooei; Mohammad Hossein Mahdian; Shahla Mahmoodi; Mohammad Hasan Masihabadi
Volume 2, Issue 3 , October 2010, , Pages 161-169
Abstract
Planning and suitable management is necessary for optimal use of soil and for this; spatial variability of soil characteristics is important which may be edcarried out through geostatistical methods of parametric and non-parametric predictors such as TPSS, WMA, Kriging and Co-kriging. This research work ...
Read More
Planning and suitable management is necessary for optimal use of soil and for this; spatial variability of soil characteristics is important which may be edcarried out through geostatistical methods of parametric and non-parametric predictors such as TPSS, WMA, Kriging and Co-kriging. This research work was done in Southern part of Uromieh plain with 36690 ha surface area in order to study the spatial variability of soil lime, sand and saturation moisture percentage. Distance between soil profiles ranged 1300 to 4700 meters. For estimation and prediction of them in non-sampled points, the Kriging, Co- kriging and Weighted Moving Average were used in Geographic Information System environment. For selecting suitable interpolation method, Cross validation and MAE and MBE parameters were used. Selected method was also used for estimating and mapping of the selected soil characteristics. The Sturges rule was used for defining map classification. Results showed that the Kriging method has the highest accuracy with correlation coefficient of 0.83 and error of 3.98 percent for prediction of soil characteristics in non-sampled points.
