فهرست مطالب آریان صلواتی

Having knowledge on the quantitative amount of watershed sediment yield is one of the most basic information to deal with soil erosion and conservation as well as design of dams. In Iran, the estimation of suspended sediment load is often based on measurement curve methods. Since sediment discharge data are random and discontinuous, in practice, their internalization and extrapolation is associated with many errors. This review is to evaluate the number of data available to estimate daily sediment load with Loadest regression models. Therefore, daily discharge data of Ghazaghli station in Gorganrood forest watershed were used. So that different percentages of available data were accidentally deleted and the amount of sediment load was estimated by 11 methods. According to the evaluation results (Taylor diagram), model number 2 has the best accuracy and in the absence of up to 50% of the daily sediment data, the correlation coefficient of more than 0/5 in the annual sediment estimation and only for the first year And in the rest of the years under study the correlation coefficient is unacceptable. Therefore, the use of sediment measurement curve methods with the data available at the level of Iranian stations, if the number of data available to construct the measurement curve is less than 185 will be associated with very little accuracy. Also, the higher the amount of available data belonging to the periods of low sediment transport (autumn and dry years), the lower the efficiency of the Loadest method will be.

Flooding is one of the natural disasters that causes many financial and financial losses every year in different parts of the world. Prioritizing natural and urban sub-basins based on vulnerability to flood can play an important role in management policies and practices in order to optimize the management of urban and natural watersheds. To this end, the combination of two AHP and Fuzzy AHP decision-making techniques with Chang's method for selective selection was used among available options for controlling and controlling flood. Sanandaj, the capital of Kurdistan province, covers an area of 3688.6 hectares in western Iran and in the southern part of Kurdistan province. Based on the aim of the study, using nine factors of area, the mean slope of the sub basin upstream, the average slope of the sub basin, basin coefficient, the ratio of impervious to permeable surfaces, drainage density, subsoil height, age of the building and height of buildings from the ground. The two methods “AHP and Fuzzy AHP” were examined and the results showed that the highest relative weight value belongs to the criterion of "the ratio of impervious surfaces to permeable surfaces", which was also based on the sensitivity analysis. There are a number of rankings differing in two techniques, which were done using the mean relative weighting method of the final prioritization. Sub-basin No. 4 in priority 1 while the Sub-basin No. 5 is in the last priority in order to consider management and control measures.