Zeinab Mohammadi Raigani; kazem Nosrati
Abstract
Accelerated soil erosion poses a serious threat to land management sustainability and water resource utilization in many areas of the world. The objective of this study was to apportion surface (cropland and rangeland) and subsurface (channel bank) sources relative contributions to the supply of suspended ...
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Accelerated soil erosion poses a serious threat to land management sustainability and water resource utilization in many areas of the world. The objective of this study was to apportion surface (cropland and rangeland) and subsurface (channel bank) sources relative contributions to the supply of suspended sediment during the storm event in Kamish mountainous catchment, using a geochemical fingerprinting approach and Bayesian un-mixing model. To this end, thirty-four geochemical tracers were measured as potential tracers to evaluate surface and subsurface sediment sources (69 samples), including 10 target suspended sediments samples collected across the hydrographs of a flood event at the overall catchment outlet. In total, two statistical methods Kruskal–Wallis H test and discriminant function analysis (DFA) were used to select the optimum tracer composition. The results of Bayesian un-mixing model indicated that mean (uncertainty range) relative contribution of cropland and rangeland (surface land-use) and channel bank (subsurface) sources are 31.8 (12.7-50.3), 33.2 (17.5-49), 35.2 (25.6- 44.6) percent, respectively. These results indicate surface and subsurface sediment sources have the same contribution to the supply of suspended sediments during the basin flood event. Although sediment sources contribution in during the flood event change intermittently between subsurface and surface soils. As a result, targeted management practices should focus through erosion and land use control of these sources for minimizing their effects on fine sediment deposition.
kazem Nosrati; sepide imeni; arash talari
Abstract
Sediment yield caused by soil erosion process as the most important land degradation index is considered a main challenge in sustainable development and threats the ecosystems. It is therefore very important to estimate the reliable sediment discharge at watersheds outlets. The large river drainage basins ...
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Sediment yield caused by soil erosion process as the most important land degradation index is considered a main challenge in sustainable development and threats the ecosystems. It is therefore very important to estimate the reliable sediment discharge at watersheds outlets. The large river drainage basins and the lack of sediment gauges have led to apply regional analysis methods, to estimate suspended sediment load in the basins without gauges or the gauges with lack of data. The objective of this study was to estimate regional suspended sediment load using principal components regression in homogeneous regions of Sefidrood drainage basin with an area of 59273 km2as dependent variable and 18 physiographic and hydrologic factors in sediment load were recognized in each homogenous region based on principal components analysis (PCA). Finally, the relationship between suspended sediment load with different return periods and controlling factors were determined. The results showed that the stations located in the study area were clustered in two homogeneous groups. In the homogeneous region one, based on the PCA, 18 variables reduced into 5 factors accounting more than 87% of total variance and in the second homogenous region reduced into 3 factors accounting more than 92%. Using the principal component regression in the first homogeneous region, the first factor with the coefficient of determination of sediment discharge with 25- year return period, 0.67, and in the second homogeneous region, the first and second factors with coefficient of determination 0.32 were entered in model.
kazem Nosrati; mohammad mehdi hossein zadeh
Abstract
Growing population and increasing water resources demand have caused to slump groundwater level in many plains. Therefore there is a necessary to improve the quantity and quality of the aquifers. One of the most important methods to increase water table in recent decade is groundwater artificial recharge. ...
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Growing population and increasing water resources demand have caused to slump groundwater level in many plains. Therefore there is a necessary to improve the quantity and quality of the aquifers. One of the most important methods to increase water table in recent decade is groundwater artificial recharge. The main objective of this study is to select sites more suitable for groundwater artificial recharge in Ravansar plain. In view of this, the raster map layers of criteria including geology, slope, alluvial thickness, infiltration rate, permeability, erodibility, land use, percent of silt and clay were prepared. Then each of these criteria was ranked using analytic hierarchy process (AHP) and weighting liner component (WLC) methods for two artificial recharge methods including flood spreading and spreading basin. The results showed that based on the selected indicators and the zonation map in two methods, the best sites located in northern, northeastern and southwestern of the study area and fluvial fans adapted with the best sites for groundwater artificial recharge.
kazem Nosrati; Saeedeh Jalali
Abstract
Identifying sediment sources is one of important factors in selecting of appropriate method of erosion control and soil conservation. The main objective of this study is to estimateuncertainty and contribution of forest roads to sediment yield in Ziarat Drainage Basin, Gorgan city using geochemical tracers. ...
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Identifying sediment sources is one of important factors in selecting of appropriate method of erosion control and soil conservation. The main objective of this study is to estimateuncertainty and contribution of forest roads to sediment yield in Ziarat Drainage Basin, Gorgan city using geochemical tracers. For this purpose, 47 soil samples were collected from different sources with different land uses and 14 suspended sediment samples collected from basin outlet. In order to identify sources of basin sediment yield and determine individual contribution of each source, 11 geochemical tracers including OC (Organic Carbon), Sr, Ni, Na, K, Cu, Fe, Mn, Ca, Mg, and Pb were measured in sediment and suspended-sediment samples. By comparing the tracers in the sediment sources and using statistical analyses of Kruskall-Wallis test and discriminant function analysis (DFA), three tracers of OC, Cu, and Fe were selected as optimum set of tracers in separating sediment sources. Eventually, using Bayesian model, land uses of agriculture, road construction and forest with 67.1(61.6-71.8), 31.4(27.1-35.9), and 1.2(0.1-5.1) percent, respectively were determined as the relative contribution from each source in sediment yield, and the highest uncertainty is related to the agricultural land use. The results of this study can be used to select the best appropriate method of erosion control in the study area and similar areas.
Kazem Nosrati; Frouzan Ahmadi; Ali Akbar Nazari Samani; Mohammad Reza Servati
Abstract
Soil erosion is one of the most destructive phenomena which cause significant ecological changes in many areas. Soil conservation and erosion control is essential because of the irreparable damage caused by soil erosion. Soil conservation programs will not achieve until to find adequate methods of combating ...
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Soil erosion is one of the most destructive phenomena which cause significant ecological changes in many areas. Soil conservation and erosion control is essential because of the irreparable damage caused by soil erosion. Soil conservation programs will not achieve until to find adequate methods of combating land degradation and ways to reduce the sediment. Therefore, we need to have enough knowledge of the sediment sources and identify places to be at high risk to soil erosion. In this study we used fingerprinting technique in the Taleghani catchment, Khorram Abad city, Lorestan Province to determine the contributions of sediment sources including agricultural, rangeland, and forest in sediment yield. In view of this, 39 soil were collected from different sources: agriculture, rangeland, forest and channel bank and 19 sediment samples including 11 samples from bed sediment and 8 samples from suspended runoff, respectively. 11 tracers including C, N, P, Na, K, Cu, Zn, Mg, Mn, Fe and Ca were selected as the primary tracers. The results showed that discriminant function analysis were selected Mg, C, Zn and Ca as the optimum set of tracers that can discriminate 3 sediment sources. Mixing model results showed that the contribution of each sediment source is 53.37, 30.37, and 16.26 percent for agriculture, rangeland, and forest, respectively. These results were consistent with the evaluation results of nitrogen and organic carbon stocks. The results of this study can be used in selecting most appropriate erosion control method the study area and generalized to similar areas.
kazem Nosrati; Mohsen Mohseni Saravi; Hasan Ahmadi; Hosein Aghighi
Abstract
Estimation of evapo-transpiration is necessary in cases such as irrigation planning, determining of evaporation of the water bodies, water balance assessment, estimation of runoff and watershed management and ecological and meteorological studies. Evapo-transpiration can be determined precisely using ...
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Estimation of evapo-transpiration is necessary in cases such as irrigation planning, determining of evaporation of the water bodies, water balance assessment, estimation of runoff and watershed management and ecological and meteorological studies. Evapo-transpiration can be determined precisely using field measurements. However, these methods provide evapo-transpiration just for limited areas from spatial point of view. This limitation has motivated the development of using remote sensing data to evaluate evapo-transpiration over vast area. Surface Energy Balance Algorithm for Land (SEBAL) is a new model that has been used at different areas all over the world for estimating of evapotranspiration. Due to the fact that no written report in evapo-transpiration estimation using this algorithm in the country has been published yet, the objective of this study is to investigate the validation of revised SEBAL model in mountainous region. In this project, actual evapo-transpiration values were estimated using MODIS image data and revised SEBAL model for mountainous region in 22 different dates in 2006 in Taleghan Drainage Basin. The result showed that the correlation between estimated and measured values is significant (R2=0.88, p<0.001). Thus, MODIS image data and revised SEBAL model were able to estimate actual daily evapo-transpiration values in Taleghan Drainage Basin. Therefore this revised algorithm could recommend as suitable method for further studies in different area with variation topography.
Mohammad Reza Sarvati; Kazem Nosrati; Shima Hassanvandi; Babak Mirbagheri
Abstract
Landslides and slope instabilities are major hazards for human activities often causing economiclosses and property damages. Sikan River Basin (Ilam province) due to the topography, tectonic,lithology, and climate has enough potential for occurrence of this phenomenon. The objectives of thisstudy were ...
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Landslides and slope instabilities are major hazards for human activities often causing economiclosses and property damages. Sikan River Basin (Ilam province) due to the topography, tectonic,lithology, and climate has enough potential for occurrence of this phenomenon. The objectives of thisstudy were to determine effective parameters controlling the landslide occurrence and to preparezonation map of landslide risk in Sykan River Basin. In view of this, 11 geophysical characteristicsincluding (height, slop, slop direction), geomorphologic (the slop of land surface), geology (lithology,the distance from the fault), hydrography (the distance from the river), coverage, land use (land useand the distance from road, the distance from village), pedology (soil texture), and dependent variable(landslide distribution) were selected an independent variable and were analyzed using logisticregression model. The results showed that the influential factors on landslides occurrence in the basinare the distance from river, land use, the distance from village, the materials (lithology), slope, and theshape of land surface. Finally, the study area was classified into five major area based on landslideoccurrence risk which 19.1 km2 of total area had very low risk, 15.9 km2 had low risk, 14.9 km2 hadaverage risk and 14.6 km2 had high risk and 9.1 km2 had also very high risk. The model evaluationshowed a high accuracy 74.2% in the study area. The results of this study can be useful for landsliderisk management and for controlling the accelerated parameters.
Kazem Nosrati
Abstract
The term hydrological drought is applied to represent low water levels in streams, reservoirs and lakes as well as a low groundwater level. Base flow index (BFI) as one of low flow indices gives the ratio of base flow to total flow and investigates basin’s ability to store and release of water in drought ...
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The term hydrological drought is applied to represent low water levels in streams, reservoirs and lakes as well as a low groundwater level. Base flow index (BFI) as one of low flow indices gives the ratio of base flow to total flow and investigates basin’s ability to store and release of water in drought periods. The objectives of this study were to determine BFI and to validate this index in drought studies of Sefidrood Drainage Basin. To view of this, first three homogenous regions were identified based on the threshold level using cluster analysis. Then, daily BFI was calculated in 28 gauging stations of the homogenous regions. The results showed that the regional mean of BFI with value of 0.65 (SD=0.19) is stable during long-period data. BFI ranged between 0.17 and 0.86 and also based on the 25, 50 and 75 percentiles, river flow regime in the study area is divided into four categories that show more than 50 percent of the catchments in the study area have low or unstable regime. So it would be hard that the catchments able to provide river flow during drought periods. Therefore the results of this study can be used in assessment of groundwater recharge, water supply system, irrigation management, and hydrological drought monitoring as well as regional modeling of water resources storage and hydrological drought in ungauged areas
