Seyed Hamidreza Sadeghi
Abstract
Awareness of the variety, quality and quantity of sediment transport rates in different time scales, is inevitable for monitoring the hydraulic behavior of channel and flow affected by the mining activities and proper management of sand removal. However, less comprehensive studies have been conducted ...
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Awareness of the variety, quality and quantity of sediment transport rates in different time scales, is inevitable for monitoring the hydraulic behavior of channel and flow affected by the mining activities and proper management of sand removal. However, less comprehensive studies have been conducted on fluvial behavior and characteristics of the bed load under different conditions. The present study therefore aimed to investigate the effect of sand mining with different harvesting and hydrological conditions on particle size distribution and morphometric characteristics of bed sediments for three sand and gravel mines viz. Vaze-e-Olia, Vaze-e-Sofla and Alesh-Roud in Mazandaran Province, Iran. In order to achieve the study purposes, different bed sediments characteristics were computed by GRADISTAT and GIAS softwares after extracting bed sediments morphometric specifications with the help of Gravelometer and Paint software for sampling sites located in the upstream and the downstream of the study mines. The samplings were taken place on monthly basis during a year from February 2012 to January 2013. The results of the study showed that the different natural and sand and gravel mining conditions and other anthropogenic activities affected the particle size distribution and morphometric characteristics of riverbed sediments. According to the statistical analyses, most of the variables were non-significantly (P>0.07) differed in the upstream and the downstream sites in the study mines.
L. Gholami; H.R. Sadeghi; A. Khaledi Darvishan; A. Telvari
Abstract
Abstract
Application of empirical models is a must owing to complexity of process, different features, spatial and temporal variation of soil erosion and non-existence or lack of pertaining data. In this study, the efficiency of rainfall and runoff variables of 11 storms during winter 2006 and spring ...
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Abstract
Application of empirical models is a must owing to complexity of process, different features, spatial and temporal variation of soil erosion and non-existence or lack of pertaining data. In this study, the efficiency of rainfall and runoff variables of 11 storms during winter 2006 and spring 2007 in explanation of storm-wise sediment yield in Chehelgazi watershed of Gheshlagh Dam basin in Kurdistan province was evaluated with the help of bivariate and multivariate regression models by using different transformed data. The models’ efficacy was then assessed by using coefficient of determination, error of estimation and verification. The results showed that bivariate regression models, using different transformed data with determination coefficient of beyond 66%, and respective error of estimation and verification of below 40 and 30%, had a better efficiency in estimation of storm-wise sediment yield than multivariate regression models. The results also verified that the rainfall variables could explain storm-wise sediment yield variations better than runoff relating factors with overall contribution of some 80%.
Key words: Sediment yield, regression models, Gheshlagh dam, Chehelgazi watershed, Kurdistan province, Iran
