Document Type : Research Paper
Authors
1 SCWMRI
2 PhD Student, Sari Agricultural Sciences and Natural Resources University
Abstract
This research was carried out to; evaluate the hydrological processes (rainfall, runoff, evaporation, infiltration, etc.), study the water capacity, to simulate the behavior of watersheds. After examining a number of simulation models, the SFBM, AWBM2002, SCS and ISDI were selected and adjusted. Data from 15 catchments and a representative watershed were used. The results such as, simulation parameters, runoff threshold, flow duration curve, snow line, flow recession curve, and base flow index are analysed. The results showed that the models, can well simulate the runoff, and are able to estimate response of ungauged catchments, and form a good capability for design and research. In more than 61.5% of the area, after a rainfall of 5 to 10 mm, runoff generates, hence it was concluded that most of the basins are susceptible to flooding. Also, the highest threshold value in the Bandar Gaz basin is 20 mm, with a maximum specific discharge of 0.27 m3/km2. The lowest value was obtained in Azadshahr and Gonbad-Kavoos basins, respectively, equal to 2 and 4 mm, with a specific instantaneous flow rate of 0.16 in the Gonbad-Kavo basin to 0.26 m3/km2 in the basin no. 171. Also, the highest threshold value in the Bandar Gaz basin is 20 mm, with a specific maximum discharge of 0.27 m3/km2. Among the basins of the similar areas, the Delour Qotorchai Basin with an area of 45.2 km2 with a maximum specific discharge of 0.49 m3/km2, the highest and middle Shor basins, with an area of 37.22 km2and Gorgan Bay with an area of 299.26 km2 with a discharge of 0.04 m3/sec/km2.The results indicated that the runoff threshold has a good correlation with precipitation. The results of the dryness model showed that the model with a high correlation coefficient (83%) simulated the discharge.
Keywords
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