Omid Kavoosi; Khaled Ahmadaali; Aliakbar Nazari Samani
Abstract
Soil erosion and its consequences, such as soil destruction at the source, silting of rivers and filling of reservoirs of dams, are one of the most important natural hazards in watersheds, which reduce ecosystem durability. To be one of the most important practical solutions to control sedimentation ...
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Soil erosion and its consequences, such as soil destruction at the source, silting of rivers and filling of reservoirs of dams, are one of the most important natural hazards in watersheds, which reduce ecosystem durability. To be one of the most important practical solutions to control sedimentation and reduce peak flow is to build a check dam. Therefore, determining the quantitative variables affecting the volume of the structure is an important factor in determining the construction costs and their effectiveness. The present study was conducted to model checkdam volumes at the level of 100 sub-basins in different provinces of Iran (Alborz, East Azerbaijan, Ilam, Isfahan, Bushehr, Tehran, Qazvin, Fars, Mazandaran, and Hamadan). The database used for modeling includes 27 environmental features extracted in each of 100 sub-basins and the modeling was done using Genetic Expression Algorithm (GEP). The results of modeling showed that the most important characteristics in estimating the volume of checkdam among the 27 characteristics are: precipitation, temperature, TWI index, shape factor, height difference, concentration time, slope, drainage density and NDVI index. The results of estimating the volume of the structures using the nine selected variables showed that the R2, RRMSE and NSE values for the training phase are .088, .035 and 0.92, respectively, and for the test phase, they are 0.91, 0.29 and 0.91, respectively. Also, based on the results, the characteristics of environmental precipitation can be used with great accuracy to estimate the volume of sediment control structures in a short time, and therefore, before their implementation, the related costs were known in order to prioritize the areas.
Amir Hossein Parsamehr; Ali Salajegheh; Shahram Khalighi; Khaled Ahmadaali
Abstract
Aim: The aim of this study is to propose an approach for modeling spatiotemporal changes in rainfall that can be used as input for rainfall-runoff models.Research Method: To achieve this, rainfall data from four rain gauge stations in the Paskouhak catchment were used. Five parameters, including elevation, ...
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Aim: The aim of this study is to propose an approach for modeling spatiotemporal changes in rainfall that can be used as input for rainfall-runoff models.Research Method: To achieve this, rainfall data from four rain gauge stations in the Paskouhak catchment were used. Five parameters, including elevation, slope, aspect, longitude, and latitude, were identified. The different combinations of these five parameters were prioritized using the gamma test in WinGammaTM software. After the use of different regression models, the best model was selected based on evaluation criteria such as R2, RMSE, and the Taylor diagram. A raster map of a selected rainfall event was drawn in the Arc GIS environment. Finally, using the proposed approach of relative equations, the spatiotemporal changes in rainfall were modeled.Results: The results showed that using a second-degree nonlinear model and parameters of elevation and latitude, it is possible to accurately obtain the spatial distribution of rainfall in the form of a regular pixel grid (100 square meters) with high precision (R2=0.917 and RMSE=0.2277).Conclusion: In different rainfall events in small catchment areas, the variation in rainfall in each pixel is almost constant relative to other pixels, including the rain gauge station, the proposed approach in this study can model the spatiotemporal changes of each rainfall event as a three-dimensional matrix in the study area. The approach can be valuable in predicting potential flood events and in water resource management and planning. However, further research is required to validate the results and test the approach in other areas.
Golnoosh Savartondrow; Salman Zare; Khaled Ahmadaali; Mohammad Jafari
Abstract
Due to the lack of water in the deserts of Iran and the high rate of evaporation, the establishment of vegetation and their irrigation are associated with many problems. Therefore, in the management programs for the sustainable development of dry and desert areas, it is very necessary to use less water. ...
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Due to the lack of water in the deserts of Iran and the high rate of evaporation, the establishment of vegetation and their irrigation are associated with many problems. Therefore, in the management programs for the sustainable development of dry and desert areas, it is very necessary to use less water. Among these methods, deep subsurface irrigation using PVC pipes can be mentioned. In this study, a hole with a depth and diameter of 50 cm was dug, and then two pipes were mutually placed at a distance of 20 cm from each other on both sides of the pit. After placing the pipes, the pit was filled with soil. The wetting pattern in eight treatments has been examined in terms of the location of the water exit holes, the diameter of the pipe, the number of holes in the upper and lower half of the pipe, as well as the diameter of the holes. The results demonstrated that pipes with a diameter of 12.5 cm and a height of 55 cm, with five double rows of 6 mm holes in the upper half of the pipe at a distance of 3 cm from each other and two holes in the lower half of the tube at a distance of 10 cm from each other, The best depth of wetting pattern is created. The depth of the wetting pattern created in the soil around the plant root as a representative of water use efficiency is very important in the management and correct use of water resources as well as encouraging the plant to take deep roots. .
Roghaye Shad; Mehdi Ghorbani; Khaled Ahmadaali; Aliakbar Nazari Samani; Maryam Yazdanparast
Abstract
Land use changes in countries like Iran, which is facing space limitations, should be thoughtful and in accordance with proper planning, just like water consumption. On the other hand, the inherent dynamism of human beings and their needs has made the way and extent of land use change over time. Therefore, ...
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Land use changes in countries like Iran, which is facing space limitations, should be thoughtful and in accordance with proper planning, just like water consumption. On the other hand, the inherent dynamism of human beings and their needs has made the way and extent of land use change over time. Therefore, the aim of this research is the dynamic modeling of land use changes based on the human-environmental system in Taleghan watershed. For this purpose, land use maps for the years 1994, 1999, 2002, 2009, 2014, 2019 were classified into six classes of pasture, forest, agricultural land, barren land, residential land, and water using Landsat satellite time series images. After the validation of the maps and the detection of changes, under the three scenarios of current economic growth, rapid economic growth and sustainable development, simulation was carried out until 1435 using dynamic system modeling. The results of detecting land use changes during the period show that the trend of changes in agricultural lands, pastures, forests, has been decreasing, and barren lands and residential areas have always had an increasing trend during the survey period. The results of the simulation show that among the three scenarios examined, the sustainable development scenario of coordination between the amount of land utilization and meeting the needs of the community and economic growth has been acceptable. Therefore, it can be concluded that the sustainable development scenario is an important basis for land use planning in the coming years in order to reduce the destruction of natural resources and maintain a stable state in it, and this scenario will bring favorable economic growth in the future.
Masoomeh Salehi Mourkani; Salman Zare; Maryam Mombeni; Ghasem Ghoohestani; Khaled Ahmadaali; Bijan Khalili Moghadam
Abstract
The influx of quicksand in the desert areas of Iran causes damage to various aspects of life of the inhabitants of these areas. Oil mulching is one of the measures that has been used for many years to stabilize quicksands. Because oil mulch is made up of heavy petroleum products, it can contaminate water ...
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The influx of quicksand in the desert areas of Iran causes damage to various aspects of life of the inhabitants of these areas. Oil mulching is one of the measures that has been used for many years to stabilize quicksands. Because oil mulch is made up of heavy petroleum products, it can contaminate water resources in these areas with heavy elements and hydrocarbons by entering water sources. To investigate the effect of heavy elements and hydrocarbons on water resources, samples of oil mulch in short-term, medium-term and long-term periods from Hamidiyeh sands of Khuzestan province and also samples of oil mulch of Abadan refinery in laboratory conditions with Simulations of natural conditions and 24-hour residence time in contact with water were investigated. The results of this study showed that the amount of pollution of heavy metals other than elemental, which in the long-term, medium-term, short-term and control area increased by 95%, 115%, 123% and 129%, respectively, than the allowable limit. Oil mulch does not have a significant effect on increasing the pollution of water resources in terms of heavy elements. Examination of oil mulch on the amount of hydrocarbons in water showed that with the exception of Naphtalene and Benzo (g, h, i) Perylene, which decreased in the medium and short term compared to the control area, the difference of other hydrocarbons compared to the control area increased. Been; But in general, the amount of all hydrocarbons studied in the studied treatments was less than their allowable limit.
Ali Yazdanpanahi; Khaled Ahmadaali; Salman Zare
Abstract
Biochar, as a soil reclamation material, has received attention by researchers during recent decades. In this study, a greenhouse experiment was conducted in a randomized complete block design (RCBD) in factorial arrangement in order to investigate the effect of natural and municipal waste compost biochars ...
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Biochar, as a soil reclamation material, has received attention by researchers during recent decades. In this study, a greenhouse experiment was conducted in a randomized complete block design (RCBD) in factorial arrangement in order to investigate the effect of natural and municipal waste compost biochars on the chemical properties of sandy soils from Kashan's sand dunes. The experimental treatments consisted of natural and municipal waste compost biochar each with four levels (0, 1, 3 and 5%) with the total of 16 culture media. Chemical analysis was performed for soil, biochar, and for 16 culture media resulting from these combinations in three replications. The results of analysis of variance and comparing means of measured characteristics (EC, pH, Ca, Mg, K, and OM) showed that these characteristics were significantly affected by the different levels of natural biochars. Soil pH decreased in some treatments and treatment No 5 had the most pH reduction. Both biochar treatments increased soil EC, pH, Ca, Mg, and OM by 5.5, 3.9, 2.4, 1.9, and 3.7 times, respectively. In general, treatment No 13 (soil + 5% natural biochar + 5% municipal waste compost biochar) had the highest influence on soil characteristics. As a practical application, the use of studied biochars as sources of Ca, Mg, K, and OM can be considered in soil reclamation projects and fertilizer management.
Ali Yazdanpanahi; Khaled Ahmadaali; Salman Zare; Toraj Shabani Omran
Abstract
This study looked into the effect of different natural and urban waste compost biochar levels (0, 1, 3, and 5%), incorporated in sandy soil (total of 16 soil types), on the saturated hydraulic conductivity coefficient. For this purpose, the hydraulic conductivity of all 16 soil samples was determined ...
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This study looked into the effect of different natural and urban waste compost biochar levels (0, 1, 3, and 5%), incorporated in sandy soil (total of 16 soil types), on the saturated hydraulic conductivity coefficient. For this purpose, the hydraulic conductivity of all 16 soil samples was determined using the constant head method. Then, for all soils, parameters of Van-Genuchten-Mualem (VGM) model for soil moisture characteristic curve (SMC) were determined by RETC and ROSETTA software and inverse modeling based on easily accessible parameters such as soil particle size percentage (sand, silt, and clay), bulk density, field capacity, and permanent wilting point. These parameters were soil residual water content (θr), soil saturated water content (θs), α, m, n and Ks. Results indicated that increasing biochars results in an increase in the Ks for all soils. Soil No. 11 (soil + 5% natural biochar + 1% urban waste compost biochar) and then soil No. 13 with 64 and 61% reduction, respectively, had the highest reduction percentage in Ks. The maximum and minimum value of Ks were 707.9 and 254.8 cmd-1 which were related to soil No. 1 and 11, respectively. All doses of biochars had a significant effect on all VGM parameters (P<0.01) and increasing biochars resulted in an increase in θr, n, and m and decrease in θs and α.
