مجله علوم و مهندسی آبخیزداری ایران
پیاپی 55 (زمستان 1400)

The main aim of this study is to estimate the Curves Number based on remote sensing and fuzzy methods for use in precipitation-runoff modelling. For this purpose, Landsat-7 satellite images were used for the second degree basin of Gorgan River, northern Iran. By making the corrections and satellite images processing using ENVI, the NDVI index of vegetation and the type of vegetation were extracted. Then, using soil map, obtained from the National's Resources Comprehensive Plan, and land slope map the type of vegetation, the CN of the sub-basins with fuzzy logic and non-fuzzy approaches calculated. To evaluate the calculated CN, a rainfall-runoff event was selected and by simulating the rainfall-runoff using HEC-HMS model, the runoff simulation was performed. The results showed that the calculated CN involving Landsat-7, using fuzzy logic simulated the runoff more accurately than non-fuzzy. So that the coefficients of determination between the observed and simulated hydrographs, obtained from non-fuzzy, fuzzy Gaussian and fuzzy trapezoidal functions were obtained equal 0.76, 0.94 and 0.84, respectively. Also, the maximum flow rate of the simulated hydrograph compared to the observed hydrograph in the fuzzy state has a difference of less than 2 m3/s compared to the non-fuzzy with a difference of 5 m3/s.

Integrated water resources management is recognized as one of the main needs of any society due to population growth and technological advancement. To implement integrated water resources management, modeling of this system is essential. On the other hand, water resources systems are highly complex and affected by various factors that are very difficult to identify and determine their role in water resources management. The purpose of this study is to prepare an integrated model taking into account economic, social and environmental dimensions using the system dynamics approach in the southern region of Kerman. To conduct this research, first in the framework of DPSIR cause and effect, a conceptual model of the region was prepared, in which the effective factors on water resources were identified. Then, different components of the basin were modeled with the approach of systems dynamics by specifying the patterns governing the region. Vensim software was used for modeling based on the system dynamics approach. After modeling, the model was validated and evaluated in different ways and it was used in the evaluation, policy-making and planning stages of the basin. The results showed that the cause-and-effect framework of DPSIR and the system dynamics-based approach for evaluating and simulating different policies in the study area are efficient and useful. In addition, the results showed that in the current scenario, the water adequacy ratio for agriculture will decrease from 0.55 in 2006 to 0.2 in 2031, but in the scenario of increasing water supply resources, the water adequacy ratio for agriculture will reach 0.9 in 2031.

The purpose of this study was investigating the effect of eleven gabion and five masonry dams on trapping eroded particles in the razin watershed located north of Kermanshah township. The frequency of sand particles increased by 40.67 percent and the percentage of gravel, silt and clay particles decreased by 14.37, 56.55 and 69.93 percent in sediments behind the gabion dams as compared to the watershed soil, respectively. The frequency of gravel particles decreased by 18.89 percent and the percentage of sand, silt and clay particles increased by 5.98, 19 and 23.39 percent in sediments behind the masonry dams as compared to the watershed soil, respectively. Gabion check dams were more useful in trapping sand particles, while the masonry check dams showed more efficiency in trapping silt and clay particles. Gabion and masonry check dams upstream of the watershed had more sand and less silt and clay than the lower dams. Percentage of silt and clay particles increased, unlike the percentage of sand particles, from the beginning of the sedimentation area to the back of the dam. This study showed that in selecting the dam type, it is necessary to investigate the particles size distribution of watershed soil and the combination of the two dam types can be more effective in trapping sediment in the watershed.

The removal of alluvial deposits from the riverbeds causes changes in the balance of the rivers. These changes are not limited to extraction and harvesting, but the miles appear higher and lower. Due to the rapid growth of industrial activities, urbanization and related developments, demand for sand has increased over the past few decades worldwide, especially in developing countries. In the present study, the HEC-RAS5.0.6 model was used to simulate the sediment flow of Allah Ramhormoz River and the hydrometric statistics of the junction stations as the upstream boundary conditions and the hydrometric statistics Meshrageh of the station as the lower boundary conditions in the 44 years old(1352-1396), transverse sections of the river, which were taken in year 87, longitudinal profile of the river, aggregate of the bed material was introduced into the model. The results of this study showed that the Ichres-White sedimentation transfer function with R2 equaled 0.87 best results have given. Also, the study of erosion and sedimentation in the river showed that from the beginning of the Allah River range to the intersection of Allah River and Zard River with an equivalent of 165 thousand cubic meters per year, the best area for harvesting.

Rainfall-Runoff simulation is one of the main subject of hydrology and environmental management. Therefore, researchers are constantly interested in finding new ways to solve this problem and modify existing models or modeling methods. However, the lack of statistics and information from the poor development of hydrological networks has always been a major problem in countries that facing financial, human and technical crises. There are also cases in border areas that have catchments shared with other countries and access to statistics and information from these catchments will be very difficult to modeling. This problem can be partially solve today by extracting the require data for modeling from global climate centers. Therefore, in this study, in order to solve this problem, try to extract the necessary information for modeling by SWAT and IHACRE integrated distribution models from NCEP CFSR climate center in the upper basin area of Dez Dam. Finally, in order to determine the ability of the models to simulate the runoff of the basin, the criteria of Nash-Satcliffe coefficient (NS) and correlation coefficient (R2) were used. The results showed that the two models performed well in using climate database information Based on this, the values ​​of Nash coefficient and correlation coefficient in SWAT model in calibration stage are 0.78 and 0.84, respectively  and In the validation stage, 0.78, 0.89  and in the IHACRES model, in the calibration stage, 0.83, 0.75, and in the validation stage, 0.77 and 0.81, respectively.

Hydraulic simulation of dam failure and estimation of damages From it, it will be of great help in the field of relief activities and proper planning in the downstream areas. In the present study, the hazardous areas due to the failure of the Ghare Aghach dam of piping type have been investigated using satellite images. Parameters due to dam failure were calculated using the BREACH model and its information was entered into HEC-RAS software. The results showed that using the BREACH model, the peak flow due to dam failure is 3318.8 cubic meters per second. The time due to dam failure was estimated to be 3.31 hours. According to HEC-RAS software, the results show that the maximum output flow due to the failure of the dam occurred 165 minutes after the simulation and is 3160.1 cubic meters per second. The flooding area of the downstream areas was estimated to be approximately 18.6 square kilometers. The area of endangered residential areas in Mehrgerd and Hosseinabad villages was estimated to be approximately 66995 and 12543 square meters, respectively. The radius of flooding relative to the coastline of the flow in the mentioned areas was estimated to be 443 and 3362 meters, respectively.