mehri raoofi; Mahmoud Habibnejad Roshan; Kaka Shahedi; Fatemeh Kardel
Abstract
Rivers are the main arteries of watersheds that play an important role in providing water for agriculture, drinking and industry. On the other hand, the reduction of river water quality has been one of the biggest human concerns in the last century. In order to evaluate the quality of running water, ...
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Rivers are the main arteries of watersheds that play an important role in providing water for agriculture, drinking and industry. On the other hand, the reduction of river water quality has been one of the biggest human concerns in the last century. In order to evaluate the quality of running water, biological indicators and the study of benthic invertebrates can be used. The aim of this study was to investigate the water quality of the main rivers of Babolrood watershed using the Hilsenhof Biological Index (HFBI). For this purpose, sampling of benthic invertebrates in 5 main river stations was performed using a net frame (sorber) with a cover area of 40 cm2 and transferred to the laboratory for identification. Then, using Pennak (1953) and Mellenby (1963) identification keys, the samples were identified by family and sex and counted and weighed. Also, at the same time as sampling of benthic organisms to study the physicochemical properties of water, samples were taken from river water. Pearson correlation coefficient was used to investigate the relationship between biological samples and physicochemical properties of water. The results showed that Babolk station with the lowest FBI and Babolrood-Babol station with the highest FBI were in the category of non-organic pollution and some organic pollution, respectively. The results of correlation of biological samples with physicochemical parameters in most cases were not significant at 95% confidence level. The highest correlation coefficient between Oligochaeta species was with Diversity biodiversity.Keywords: Benthic invertebrates, water quality, HFBI, Babolrood watershed, Mazandaran province
Mahmoud Habibnejad Roshan; Kaka Shahedi; Sayed Hussein Roshun
Abstract
Introduction
Floods are one of the most destructive natural disasters that cause severe injuries and loss of life, major infrastructure damage, significant economic losses, and social unrest worldwide. Due to the fact that flood is a dynamic and multidimensional phenomenon, Geographic Information System ...
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Introduction
Floods are one of the most destructive natural disasters that cause severe injuries and loss of life, major infrastructure damage, significant economic losses, and social unrest worldwide. Due to the fact that flood is a dynamic and multidimensional phenomenon, Geographic Information System (GIS) and Remote Sensing (RS) data are used to a large extent to discover the extent of flooded areas and play a special role in preparing flood risk and susceptibility maps. Flood susceptibility mapping is essential for characterizing flood risk areas and planning flood control schemes.
Materials and methods
In this research, the identification of flooded areas in the Karun Watershed based on the Analytical Hierarchy Process (AHP) in the GIS environment and its validation with the NDWI blue index extracted from Landsat 8 satellite images has been considered. For this purpose, first, 15 effective parameters in floods occurrence including slope, aspect, elevation, curvature, rainfall, distance from stream, stream density, distance from fault, fault density, distance from road, road density, lithology, Curve Number (CN), land use, Topographic Wetness Index (TWI) and Stream Power Index (SPI) were selected and the weighting of these parameters was done based on AHP method in the Expert Choice software environment. Finally, by using the command to combine the layers based on the weighting of the AHP method in GIS, the final flood risk zoning map was obtained. NDWI water index was used to validate the flood risk map obtained.
Results and discussion
The results of the AHP model showed that the most effective factors in the occurrence of flood risk in the Karun Watershed include rainfall, the amount of slope and the height classes, which should be considered in order to reduce flood damage and provide management solutions for these factors. Also, the results show that the downstream areas of the watershed have the highest risk of flooding and more than half of the watershed's surface (52.24%) has a medium flood potential.
Conclusion
Preparing a map of flood-prone areas is one of the most constructive methods that enable the reduction of flood risk damages and help planners, stakeholders and decision-makers to properly monitor flood-prone areas and ensure appropriate and sustainable socio-economic development.
hasan izanloo; kaka shahedi; karim solaimani
Abstract
Assessment of metals absorbed to suspended solids in urban floods, allows managers to take measures to improve the quality of the urban environment. This article examines the changes in the concentration of heavy metals such as lead, zinc and copper in suspended load of runoff from the Bojnourd urban ...
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Assessment of metals absorbed to suspended solids in urban floods, allows managers to take measures to improve the quality of the urban environment. This article examines the changes in the concentration of heavy metals such as lead, zinc and copper in suspended load of runoff from the Bojnourd urban watershed in autumn and spring seasons. For this reason, 52 samples were collected. After preparing the samples, separation of suspended sediment using the Whatman filter paper and then weighing the amount of sediment in runoff, using atomic absorption, the amount of heavy metals dissolved in runoff and heavy metals absorbed to suspended solids in runoff were measured in terms of ppb. The results showed that the amount of suspended sediment weight is higher in spring than autumn. Results indicated that the maximum concentration of insoluble heavy metals and attached to sediments is more than soluble heavy metals in runoff. On the other hand, the results revealed that the mean maximum concentration of zinc and copper, except lead attached to sediments, is higher in the spring than autumn and the spatial concentration of zinc and copper in samples of runoff suspended sediments from Sandalabad Stream (FC3S) is higher. While on the lead, concentration for the samples taken from the runoff pathways and drainage network (FB2S) was higher. However, the difference in location of data for heavy metals absorbed to suspended sediments is not statistically significant. The Pearson correlation test results showed that there is a positive but low correlation between lead and zinc (r =0.166) in the autumn and the lead and copper (r=0.271) in the spring. Significance of this correlation is certified using hierarchical cluster analysis method.
Seyed Pedram Nainiva; Kaka Shahedi; Salahudin Zahedi; Hersh Entezami
Abstract
Snow cover has a significant role in management and supply of water resources in mountainous basins. In this order, this study aimed at estimating of contribution the snowmelt runoff in Chehelgazi Sub-basin at Kurdistan Province in supplying water requirements of its farmlands during 2012 and 2014. To ...
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Snow cover has a significant role in management and supply of water resources in mountainous basins. In this order, this study aimed at estimating of contribution the snowmelt runoff in Chehelgazi Sub-basin at Kurdistan Province in supplying water requirements of its farmlands during 2012 and 2014. To do so, SRM model and MODIS satellite images were applied to estimate runoff from the snowmelt and CROPWAT model was implemented to determine water requirements of farmlands. Through the findings, it was found that SRM model with coefficient of determination (R2) of 0.97 and volume difference percentage of 0.14 for the calibration year (2012-2013) and coefficient of determination of 0.96 and volume difference percentage of 0.66 for validation year (2013-2014) was able to estimate snowmelt runoff. Moreover, the result from CROPWAT model showed that water requirement for farmlands in Chehelgazi Sub-basin was 1939371 m3yr-1. Ultimately, it was shown through the model that runoff from the snowmelt has 100 % potential in supplying water requirements in the basin. The result from this study can be used to provide a model for water planning in Chehelgazi Sub-basin.
Salahudin Zahedi; Kaka Shahedi; Mahmod Habibnejad Rawshan; Karim Solimani; Kourosh Dadkhah
Abstract
This study was conducted to evaluate the capability of the DHSVM model to simulate hydrological processes in a mountainous watershed with a minimum agricultural land use. The required climatic parameters were set for the daily time step. The inverse distance method was used to interpolate the climatic ...
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This study was conducted to evaluate the capability of the DHSVM model to simulate hydrological processes in a mountainous watershed with a minimum agricultural land use. The required climatic parameters were set for the daily time step. The inverse distance method was used to interpolate the climatic variables from the stations to the network cells. Time inputs to the model were prepared for the years 2008 to 2013. The land cover map was prepared using the supervised classification method of Landsat TM data. The stream network map was generated using the DEM map in ArcGIS software. The soil texture map was prepared using field sampling and in the laboratory. Primary tests to the determine sensitivity of input parameters showed that this model is sensitive to lateral hydraulic conductivity, exponential coefficient of hydraulic conductivity, porosity, field capacity, and minimum stomatal resistance. In this study, except for the lateral hydraulic conductivity and exponential decrease coefficient, all other parameters (soil and vegetation) were determined based on previous studies and field measurements in a similar way for both categories of data. The time series of the data were divided into three, warm- up or preparation periods (2008-2009), calibration (2009-2011) and validation (2011-2013). The model was calibrated using streamflow data from 2008 to 2010. Different efficiency criteria were calculated between simulated and observed flows. NSE value for calibrating was 0.59 and for validation was 0.606. In general, the results of this model implementation in the studied basin with the quality and quantity of input data to the model are satisfactory.
Hamid Darabi; Kaka Shahedi; Mehdi Mardian
Abstract
Because of data lacking in the most of watersheds, many researchers applied spatial analysis in GIS environment to study the hydrological and flooding condition. This study aims to map flood susceptibility through frequency ratio technique using some parameters such as digital elevation technique, slope, ...
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Because of data lacking in the most of watersheds, many researchers applied spatial analysis in GIS environment to study the hydrological and flooding condition. This study aims to map flood susceptibility through frequency ratio technique using some parameters such as digital elevation technique, slope, curvature, topographic wetness index, stream power index, average rainfall, distance from river, geology, soil type and land use in Pole-Doab, Shazand Watereshed, Makazi Province, Iran. First, digital map of all of the parameters were prepared based on raster format using Arc GIS 10.1 and SAGA GIS2 softwares. To prepare land-use map IRS-1C satellite image, ENVI 4.8 software and maximum likelihood algorithm were applied. Then flood inventory map was produced by mapping 95 flood prone locations in the study area using documented information on the May-2003, May-2004 and March-2004 floods. These 95 locations divided into two groups including 67 points (70%) and 28 points (30%) for calibration and validation, respectively. For calibration, flood prone locations defined as dependent variable and ten parameters that are affecting flooding condition were introduced to frequency ratio as independent variables. Then flood probability was determined for each class of each parameter. Finally, obtained weights for each class in GIS were implemented in corresponding layers and using the overlay algorithm, susceptibility and probability maps were prepared. Based on the susceptibility map, study area was divided into 5 classes as very high, high, medium, low and very low sensitivity. The findings of the assessment of frequency ratio histogram indicated that the likelihood of very high and very low flooding classes are equal to 67.86 and zero percent, respectively. Therefore, the obtained frequency ratio histogram confirms the adequacy of the implemented method in flood susceptibility and probability mapping for the case study.
