watershed
Mahnaz Saber; Bromand Salahi; Roghayeh Maleki Meresht
Abstract
The SWAT model was used in this research to simulate the hydrological conditions of the Aras River basin in the future period. The model was calibrated based on the data of 1987-2006 and its validation was done in 2007-2014 with the SUFI2 algorithm and the SWAT model was calibrated based on the monthly ...
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The SWAT model was used in this research to simulate the hydrological conditions of the Aras River basin in the future period. The model was calibrated based on the data of 1987-2006 and its validation was done in 2007-2014 with the SUFI2 algorithm and the SWAT model was calibrated based on the monthly flow rate of the selected hydrometric station. After selecting the optimal parameters and running the simulation in 350 simulator rounds, the values of the evaluation criteria were obtained in the calibration period and in the validation phase. To evaluate the water balance changes of the basin under the conditions of climate change from the downscaled data of the CNRM-CM6 climate model in the historical period (1985-2014) and the future period (2025-2100) under the SSP5-8.5 scenario were used as input data to the SWAT model. The findings showed that evapotranspiration of the Aras basin has wasted a large share of the precipitation of 272mm in the historical period and 351 mm in the future period of the basin, and the amount of infiltration and lateral flow, which are necessary to feeding underground and surface resources, is very low. Also in terms of land use, the minimum ET of the basin was calculated in the use of good pastures. Also, the findings showed that although in the future period the annual rainfall will be 79 mm more than the historical period, but a major part of it will be spent on evapotranspiration in the months of May to July.
watershed
mehdi feyzolahpour
Abstract
Changes in land cover and land use due to human activities have left adverse effects on the environment. The eastern regions of Ardabil province are a clear example of this phenomenon. The purpose of this research is to analyze spatial and temporal changes in land cover and land use and its effects on ...
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Changes in land cover and land use due to human activities have left adverse effects on the environment. The eastern regions of Ardabil province are a clear example of this phenomenon. The purpose of this research is to analyze spatial and temporal changes in land cover and land use and its effects on the temperature of the surface of the earth in Lake Neor. To estimate land use and land cover, random forest models (RTC), maximum likelihood model (MLC) and support vector machine (SVM) were used and the efficiency of each was estimated by the Kappa coefficient and it was observed that the SVM model has the highest Kappa coefficient (0.87) Bands 6, 5 and 10 of Landsat 8 were also used to extract the LST index, and it was observed that the western part of the lake faced an increase in the temperature of the earth's surface. During the time period of 2002, 2013 and 2022, significant changes were observed in the water area of Neor Lake and its nearby vegetation. Barren lands had the largest extent in all studied periods. Vegetation has increased by 1.04 square kilometers based on SVM model. The surface area of the lake was estimated as 3.19 square kilometers based on the MLC model in 2002. The area of the water zone in the MLC model has decreased by 1.56 square kilometers between 2002 and 2022, and this decrease is 0.67 and 0.69 square kilometers for the RTC and SVM models, respectively.
watershed
Sepideh siyooti; Alireza Ildoromi; Behnoosh Farrokhzadeh
Abstract
In this research, the flood-blocking nodes of the drainage network in Khako (Faqira-Khidr) urban basin of Hamedan were measured and evaluated using the SWMM model. The results showed that the infiltration and runoff height of the project in the SCS method are equal to 50.86 and 16.14 mm, respectively, ...
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In this research, the flood-blocking nodes of the drainage network in Khako (Faqira-Khidr) urban basin of Hamedan were measured and evaluated using the SWMM model. The results showed that the infiltration and runoff height of the project in the SCS method are equal to 50.86 and 16.14 mm, respectively, and this indicates that the SCS method is a more accurate assessment of the infiltration and runoff values for the Hamadan urban watershed. and has an acceptable efficiency. The results show that out of the total rainfall of 120 mm, 33 mm is related to infiltration losses and 87 mm is related to surface runoff, and the flow volume is equal to 2.41 million cubic meters, which is 1.98 1 million cubic meters is related to Faqireh sub-basin and 0.43 million cubic meters is related to Khizr sub-basin. According to the efficiency coefficient of NS, which is calculated as 0.66 for the peak discharge and 0.73 for the flood volume, and these numbers are acceptable. The results showed that the highest volume of rainfall runoff of the project with 1.28 million cubic meters is related to Faqirah sub-basin due to the physical development of Hamedan city in recent years in this sub-basin and the lowest amount with 0.46 million cubic meters is related to the sub-basin. It is Khedrkhako. The results of this research showed that residential uses have the largest share in the flood potential of the study area.
watershed
Masoud Motaghian; Reza Ghazavi; Seyed Hassan Alavinia
Abstract
Comprehensive management is a new concept and a new approach in planning, development, management of water resources and vegetation with special emphasis on economic, social and environmental issues. The purpose of this research is to present the comprehensive management strategies of the Dubai Basin ...
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Comprehensive management is a new concept and a new approach in planning, development, management of water resources and vegetation with special emphasis on economic, social and environmental issues. The purpose of this research is to present the comprehensive management strategies of the Dubai Basin using the SWOT model and determine the implementation priority with QSPM. For this purpose, first the weaknesses, strengths, opportunities and threats of the studied basin were extracted using the brainstorming method and group decision-making for the Doabi watershed in Tehran province, and then the relative importance and final value of each factor in the matrix was determined and analyzed. In order to prioritize the strategies, the QSPM matrix was also used. The results of this study showed that the component of the presence of springs, aqueducts and rivers in the basin with a weight of 0.24 as the most important strength, two weak components of lack of water and humidity in the downstream areas of the basin and low rainfall in the outlet area of the basin with a weight score of 0.24 as The most important weak points, the component of grade 1, 2 and 3 asphalt and dirt roads with a weight of 0.16 have been identified as the most important opportunity and the component of flood and its resulting damages with a weight of 0.18 as the most important threat. The results also showed that the evaluation matrix of internal and external factors was 3.15 and 3.16, which indicated the dominance of strengths over weaknesses and opportunities over threats. In other words, the Doabi watershed is in an aggressive strategy. In order to manage opportunities and strengthen those, strategies were proposed and based on the QSPM matrix, management operations were placed as the first priority and biological operations were placed as the second executive priority.
watershed
Karim Solaimani; Seyedhossien Alavi; Fatemeh Shokrian; Esmaeil Mokhtarpour
Abstract
This study investigated the trend of hydroclimate parameters of the Miankaleh wetland using the Mann-Kendall test and Sen slope estimator. Temperature, precipitation, and evaporation parameters were used from the synoptic stations . Also, the discharge data were used from the hydrometric stations of ...
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This study investigated the trend of hydroclimate parameters of the Miankaleh wetland using the Mann-Kendall test and Sen slope estimator. Temperature, precipitation, and evaporation parameters were used from the synoptic stations . Also, the discharge data were used from the hydrometric stations of Khalil Mahalleh, Tazeh Abad, Baghoo, and Vatana stations. The results of the Mann-Kendall test showed that the temperature in the Dashte-Naz station in spring and summer seasons has a significant increasing trend with 95% confidence and a significant decreasing trend in winter. Also, there is an increasing trend in Hashem Abad station, with a 95% confidence level in the spring and autumn seasons. Precipitation in Dashte-Naz station with a 95% confidence level has a decreasing and increasing trend, respectively. The most frequent trend changes in Dubai are related to Vatana station, which has a decreasing trend on an annual scale. Evaporation in Dashte-Naz station has a decreasing trend in the autumn and winter seasons and has an increasing trend in spring. Also, in Hashem Abad station, the evaporation rate in autumn has a decreasing trend. The Sen slope estimator method results showed that precipitation in Dashte-Naz station in December was -2.983, and on the annual scale, it is related to Hashem Abad station with -6.283. The highest monthly positive trend line slope of all parameters is related to August precipitation in Dashte- Naz station with a value of 3.20, and the highest annual scale is related to evaporation in Hashem Abad station with a value of 2.157.
watershed
Razieh Izanloo; Ebrahim Omidvar
Abstract
The damming can cause changes in the hydrological regime of the river. There is a crucial need to understand the potential impacts of water structures on river hydrologic regimes in order to set managed environmental flows. In this study, the statistics of Tang Esferjan hydrometric station at the outlet ...
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The damming can cause changes in the hydrological regime of the river. There is a crucial need to understand the potential impacts of water structures on river hydrologic regimes in order to set managed environmental flows. In this study, the statistics of Tang Esferjan hydrometric station at the outlet of Hoonejan watershed (Isfahan province) were used to investigate the monthly average discharge and flow duration curve alteration using IHA software (version 7.1). The amount of monthly flow has decreased in the post impact compared to the pre impact period. The flow duration curve is higher in all seasons before the construction of check-dams than after construction. The interpretation of flow duration curves shows the reducing effect of correction clauses in all types of flow. The hydrological indicators of the stream (normal discharge index in the high flow condition, normal discharge index in the low flow condition and normal discharge index) have decreased in the post-impact period compared to the pre-impact period. In all months of the year, except for February, March and April, the rate of decrease of the normal discharge index in the low flow condition (Q75) was higher than the normal discharge index in the high flow condition (Q25). The normal discharge index in the high flow condition has decreased more in the spring season than in other seasons after damming. The normal discharge index in the low flow condition in winter, autumn (91%) and summer (90%) has decreased more than in spring.
