پژوهشی
Sayyad Asghari Sarskanroon; Batool Zeinali; Nader Poornariman
Volume 2, Issue 3 , January 2017, Pages 1-20
Abstract
Rivers are dynamic systems that lateral boundaries and their morphologic characteristics are changing in time continuously. This instability is created by erodibility of river bed and consequently river patterns changing. Case study of this research is Germi Chay in East Azerbaijan province. ...
Read More
Rivers are dynamic systems that lateral boundaries and their morphologic characteristics are changing in time continuously. This instability is created by erodibility of river bed and consequently river patterns changing. Case study of this research is Germi Chay in East Azerbaijan province. The purposes of this study are investigation of river patterns and determining erodibility of river route. For these used Landsat satellite images, digital elevation model (DEM), vegetation, geologic and land use maps. In order to determining of river pattern and its Effective factors were used Sinuosity, Central angle indexes and longitudinal profile analysis. Finally river erodibility classes were determined in 5 classes by overlaying effective layers in erodibility. Results indicated pattern of studied river is meandering. Longitudinal profile analysis in both intervals indicated that changing of situation is not seen in longitudinal profile and these changes are in a normal state. This is indicator regular trend in effective factors of river morphological actions. Also results indicated that erodible areas of Medium to high and high are in parts with Structures sensitive to erosion (mainly Quaternary sediments), the lack of suitable and dense vegetation that are caused slope movements in river bed.
پژوهشی
Abolgassem Amir Ahmadi; Maliheh Mohammadnia; Negar Golshani
Volume 2, Issue 3 , January 2017, Pages 21-42
Abstract
Methods used for identification, separation and prioritization of flood prone areas generally consider the basin as a whole, or as regional regardless of the physical borders of the basin or the sub-basin. Hnnenjan Zrchshmh basin is located in Shahreza in Esfahan province. Every year, floods inflict ...
Read More
Methods used for identification, separation and prioritization of flood prone areas generally consider the basin as a whole, or as regional regardless of the physical borders of the basin or the sub-basin. Hnnenjan Zrchshmh basin is located in Shahreza in Esfahan province. Every year, floods inflict considerable damage to large areas of its lands, rivers and orchards. Identifying and predicting the flood volume of these basins which undoubtedly condition the downstream areas and identifying the priorities and sensitivity of the sub-basins for flood control programs, is of great necessity. This study uses hydrological simulation method via HEC-HMS software to reconstruct and evaluate the routing flood hydrographs in the basin and analyze the sensitivity of flood discharges with respect to the parameters of the watershed in addition to CN, slope and area of each sub-basin in its logical extension. Calculation of the results in this study show that the kind of sub-basin participation in output flood are not necessarily proportional to the peak and that the sub-basins with high peak are not necessarily more effective in sealing the watershed outlet. Therefore, for any flood control operation or reduction of the peak flows in the watershed outlet, the effect of each basin after routing of the main channels must be determined. Then according to the share they have in the output seal, they should be prioritized and divided. Implementing the individual omission method of basins in the Hunejan Zrchshmh basin model with HEC-HMS software it was determined that the S13 sub-basin has the most and the S3 has the least decreasing effect on the output peak flow of the basin. Furthermore, increased CN in sub-basins S13-S5-S11-S12-S10-S15-S6 have increased the peak flow. Sub-basins S12-S13-S5-S10 showed greater sensitivity to changes in the area. Also the slope increase in the sub-basins S2, S4, S5, S7, S10, S12, S13, S15, S16, S17, S21, S22, and S24 has had a direct impact on the increase in peak flow output, having the reverse effect on other sub-basins.
پژوهشی
Hashem Rostamzadeh; Mohammad Reza Nikjoo; Ismaeil Asadi; Jafar Jafarzadeh
Volume 2, Issue 3 , January 2017, Pages 43-60
Abstract
Ardabil Plain is an intermountain area of approximately 820 square kilometers in northwestern Iran, located in the eastern plateau of Azerbaijan within the province of Ardabil. Plain water needed for agriculture, industry and drinking are provided from rivers, deep and semi-deep wells and springs in ...
Read More
Ardabil Plain is an intermountain area of approximately 820 square kilometers in northwestern Iran, located in the eastern plateau of Azerbaijan within the province of Ardabil. Plain water needed for agriculture, industry and drinking are provided from rivers, deep and semi-deep wells and springs in the current area. To check the quality of groundwater in Ardabil, the data on 56 deep wells, 3 semi-deep wells, 3 aqueducts and fountains, and 7 mouthpiece of streams based on 1389 Regional Water Authority records were sampled. The purpose of this study was to provide an overview of the quality of potable groundwater of Ardabil Plain by using electrical conductivity, PH, SO4--, Cl-, Na and total hardness (in CaCo3) and geostatistical techniques in GIS software through ArcGIS10.3 to produce thematic maps of groundwater quality is Ardabil Plain. The ordinary kriging interpolation method to obtain the spatial distribution of parameters and simple additive weight for weighting and ranking layers were also used. Finally, with regard to the quality of the final map, it was detected that approximately 34 percent (about 280 kilometers) of groundwater for drinking at an optimal level in Ardabil Plain is located on the east side and that the lower quality water belonged to the southwest and northwest of the plain. Also, it was found that there is a direct relationship between the density of population and density of existing wells in the Plain.
پژوهشی
Asadollah Hejazi; Sogra Andariani; Farhad Almaspour; Abolfazl Mokhtari Asl
Volume 2, Issue 3 , January 2017, Pages 61-80
Abstract
Flood is the main destructive phenomena in Iran which causes human casualties and financial damages every year. The purpose of this research is to define flood susceptible zones in Ligcanchai Catchment. To achieve this end this study provided different information layers such as slope, elevation, ...
Read More
Flood is the main destructive phenomena in Iran which causes human casualties and financial damages every year. The purpose of this research is to define flood susceptible zones in Ligcanchai Catchment. To achieve this end this study provided different information layers such as slope, elevation, soil hydrological units, curve number, runoff height, lithology, land use and landcover, hydrography density, compactness coefficient of 23 basins by using maps, reports, satellite images and field studies. All layers were then weighted with criteria and sub criteria. The study used the hierarchical method to weight criteria and fuzzy logic to weight sub criteria. Then 5 flood susceptible zones were defined by using multi-criteria evaluation and linear combination was weighted. The results show that around 28 percent of the Catchment has high and very high flood risk and that these areas are located near Tabriz city. Since flood events destroy the infrastructures and cause human casualties every year, substantial actions must be taken to prevent the high and very high flood risks. These activities must be planned in the integrated watershed management plans, and the flood risk management in order to improve the watershed vegetation in the watershed to minimize financial damages and human life losses.
پژوهشی
Amir Saffari; Mariyam Jan Ahmadi; Monireh Raeati Shavazi
Volume 2, Issue 3 , January 2017, Pages 81-97
Abstract
Nowadays, one of the main problems that the societies encounter is discharging of the ground waters and the lack of suitable substitution for that. In Bushkan Plain vast use of agricultural lands has caused a drop in groundwater level. One of the suitable solutions to reduce this crisis is artificial ...
Read More
Nowadays, one of the main problems that the societies encounter is discharging of the ground waters and the lack of suitable substitution for that. In Bushkan Plain vast use of agricultural lands has caused a drop in groundwater level. One of the suitable solutions to reduce this crisis is artificial feeding of groundwaters. To this end, the most important step in the floodwater spreading plan is suitable zonation for water spreading and forcing the water to penetrate into underground water tables. In this study, a hybrid AHP-Fuzzy method in Geographic Information Systems (GIS) and 8 parameters of the slope, alluvium thickness, electrical conductivity, geology, land use, drainage density, conductivity and altitude are used. First, these layers were converted to Fuzzy and then were evaluated using Analytical Hierarchy Process (AHP) and Expert Choice software. The values achieved in ARC GIS 10/2 on fuzzy layer were multiplied to Fuzzified layers by using Raster calculator and were combined with Fuzzy overlay command and the final maps were then prepared. The results show that gamma value of 0/9 has the best overlapping and eventually, the optimal gamma was found on 5 classes as high improper, improper, average, proper and high proper in the plain. 7/11 percent of the study area was calculated within high improper class, and 11/1 percent of the study area belonged to the high proper class. The southwestern parts of the plain, where pasturage density is low, are the best areas for flood spreading.
پژوهشی
Mousa Abedini; Mohammad Hossein Fathi
Volume 2, Issue 3 , January 2017, Pages 99-120
Abstract
Flood is one of the most common natural worldwide hazards that causes enormous losses of life and property throughout the world. Therefore, the development of flood mapping forecast models is curial in decision making before the flood and for the after flood management. The aim of this study is to determine ...
Read More
Flood is one of the most common natural worldwide hazards that causes enormous losses of life and property throughout the world. Therefore, the development of flood mapping forecast models is curial in decision making before the flood and for the after flood management. The aim of this study is to determine the flood hazard zones in the khiav Chai basin using the network analysis process. To implement this model in the area under study, various data such as rainfall, land use, slope-morphological characteristics such as convexity (profile curvature) convergence divergence slopes (plan curvature), steep slopes, vegetation index (NDVI), distance from major rivers and drainage network density were considered. The results obtained from the network Analyzer model shows the fact that more than 15 percent of the area affected by the floods with very high potential risk of occurrence are mainly located at the bottom of the basin. These levels are often less than 35% in slope, with low vegetation density profiles, converged areas with concave surfaces, and areas near rivers. Analysis of the final weights derived from the AHP in relation to flood risk shows that the slope of the geological formations operating by 0/99, and 0/822 value, have the highest impact and influence, regarding the high degree of control and influence they have on the amount of runoff and discharge of the surface area. The importance and influence of the SPI with 0/226 and 0/065 STI are of less important compared to other factors.
پژوهشی
Ezzatollah Ghanavati; Feridoun Babaee Agdam; Taher Hemmati; Masoud Rahimi
Volume 2, Issue 3 , January 2017, Pages 121-135
Abstract
Khiav Chai basin is located in Ardabil province as the sub basin of Gharasou basin. The
main river of this basin is Khiav Chai basin originating from the Sabalan Mountain,
which after passing through the Moeil valley flows into Gharasou River. Since the
Meshkin Shahr city is located downstream of ...
Read More
Khiav Chai basin is located in Ardabil province as the sub basin of Gharasou basin. The
main river of this basin is Khiav Chai basin originating from the Sabalan Mountain,
which after passing through the Moeil valley flows into Gharasou River. Since the
Meshkin Shahr city is located downstream of this basin and is facing the frequent
danger of flooding, there should be special attention to prevent the flooding risk in this
area. This study focuses on the zoning potential floods in Khiav Chai basin using the
Fuzzy logic. To achieve this end, 8 parameters are used in this study including
vegetation density, drainage density, distance from drainage, lithology, land use,
rainfall, altitude and slope. In this model, all the layers with raster format were uploaded
into the Arc GIS software. Then the layers were fuzzified according to their functions.
In the next step, using different Fuzzy model functions, the zoning of the flooding of the
basin was completed. The results showed that the valleys, thalwegs with concave
slopes, and downstream areas were the most effective watershed areas in preventing
flood hazards. The results of this research can help reduce the loss of life and property
in downstream residential parts in the area, and can also be used as a basis for further
studies in relation to natural hazards.
پژوهشی
Mojtaba Yamani; Abolghasem Gourabi; Zahra Abedini
Volume 2, Issue 3 , January 2017, Pages 137-157
Abstract
Rivers are dynamic systems and their space-time characteristics are constantly changing. This change and displacement creates problems in the human and ecological functions and the study of such changes are the main issues in the fluvial geomorphology. In this study, survey morphological changes in one ...
Read More
Rivers are dynamic systems and their space-time characteristics are constantly changing. This change and displacement creates problems in the human and ecological functions and the study of such changes are the main issues in the fluvial geomorphology. In this study, survey morphological changes in one section of the Babolroud (Bobol River) will be examined during the time period of 1334-93 from Babol city to Kardgarkola village within 18/45 km. Using aerial photo from 1334 and 1383 and satellite images Landsat 8, 1393 the path of the river was digitalized in three time periods with Arc GIS software. To determine the type of changes in each of the beaches spatial and temporal interval were studied and the position of the coastline was compared to the previous coastline. Then, for each beach in each period shifts named layer was prepared and its surface was measured. Then for each time interval (period) studied, the spatial interval was specified. The statistical tables were considered for each time interval to provide possible comparisons between the spatial intervals. Finally, changes in the left and right of each interval in each period was compared to the period before. For a detailed analysis, changes in the stream in each of the study periods were considered after determining the thalweg, the fixed line and the taken transects within the interval of 1000 to 1000 meters. Then, in the Arc GIS, after the determining the transects and thalwegs, and creating a polygon, the area of polygon was compared to the previous periods. Finally, through the implementation of existing disputes, thalweg changes in the riverbed, which determined the cause of the change, was found in each transect. The results show that the interval in the regression process has three periods. The second interval depicted the greatest change. The main reason for this fact in the period of change is excessive land use and human intervention.
