Sharif Digital Repository

Lake Urmia in northwest Iran is an important water body at the national and international level and plays a significant role in the natural, social, and economic aspects of life in the region. Unfortunately, as a result of natural and anthropologic factors, the lake has suffered a severe water decline in recent decades and was even on the verge of complete drying. Being aware of the catastrophic consequences of lake Urmia's desiccation, a megaproject called Urmia Lake Restoration Program (ULRP) aiming to revive the lake was launched in 2013. Failure in megaprojects is common and frequent in which a high level of uncertainty is one of the main contributing factors. The purpose of this study... 

The purpose of this research is to first provide an algorithm to reduce the scale of large-scale microwave soil moisture images and then develop an algorithm based on it to manage the release of dams downstream of which are agricultural lands and wetlands. Considering that providing irrigation needs is the purpose of building dams and agriculture is the main consumer of water in dams, optimizing the related releases has a significant effect on reducing water consumption and the possibility of releasing more water for water needs. It has a downstream environment, also agricultural water management has a direct impact on the production of agricultural products and preservation of natural... 

Surface water quality management needs water contaminants monitoring and information about water quality parameters. Field measurement is a costly, time-consuming procedure that limits information about the whole surface of a water body. Remote sensing methods are valuable ways that prepare water quality information using different characteristics between reflectance detected from each parameter. This study aimed to investigate the water quality parameters of Gorgan Bay using field sampling and a feasibility study using Landsat-8 and Sentinel-2 images to estimate the spatial and temporal changes of optically active parameters (such as sea surface temperature (SST), salinity, electrical... 

The Mashhad plain is one of the most important plains in Khorasan-e-Razavi province. In the last decades, rapid population growth coupled with agricultural expansion has tremendously increases pressure on the groundwater resources. Large increases in water demands with little recharge have strained the plain groundwater resources resulting in declines in water level in last decades. Due to declining of groundwater level, digging new wells has been forbidden since 1965. In this thesis, users in agricultural, municipals and industrial sections have been modeled with Multi-Agent System, and results of their water extraction on groundwater level have been modeled with GMS. There are two... 

understanding basin’s sediment transportation forms and river’s bed erosion in next years in addition to rivers’ response to watershed upstream activities, gives useful information to relevant experts for fundamental studies on expanding of development projects in neighborhood of kan River. This project is an effort to assess the amount of sediment production of Kan River’s basin using SWAT, modeling calibration by using measured data with SWAT-CUP and also prediction of river’s response to watershed activities in modeling river’s sediment in next years by using HEC-RAS. Several management approaches in different scenarios has been studied in order to control the sediment production and... 

Iran like other Developing countries is prone to natural disasters. Not only these countries are situated in areas exposed to geological and climatic hazards, but they most significantly lack policies for hazard prevention and mitigation. A considerable amount of residential areas and installations in Tehran are on the mountainous hillsides, therefore the risk related to debris flows has been enlarged. Debris flows represent one of the most dangerous geomorphologic hazards that occur in mountainous areas. Their high mobility can cause damage, not only inside and adjacent to the torrent, but also on the debris fan. The main purpose of this thesis is to present a straight forward procedure to... 

Since physical variables are almost dependent, uncertain and have significant time and spatial changes, nature of hydrological and environmental systems is so complicated, nonlinear and dynamic. Many models have been developed for studying and analyzing various phenomena in these systems. Recently data mining approaches have been used as new methods for modeling of complicated engineering systems. In this study, performance of several data mining tools in analyzing two phenomena in water quality management have been evaluated. These algorithms are Multilayer Perceptron Neural Network (MLP), Radial Basis Function Neural Network (RBFN), Support Vector Machines (SVMs) in the field of Artificial... 

In recent decades, local, regional and national research programs have discovered stormwater runoff as the principal cause of water pollution in most urban areas. To solve urban stormwater runoff problems, we should use revisory measures. This is possible by using Best Management Practices (BMPs). BMPs are innovative technologies to reduce the movement of pollutants from land into surface or groundwaters, in order to protect water quality within natural and economic limitations.Three types of BMPs are discussed in this study; swale, bioretention systems and pond. They have different installation requirements, costs and pollutant removal efficiency. The main objective of this research is to... 

study has been divided into two main sections. In the first section, six climate variables have been analyzed in 15 synoptic stations in Iran’s west region through parametric and non-parametric statistical tests in order to find the climate varibility. The results illustared that, in general, there is no climate variability in the western part of Iran. Investigation of climatic indices and changes in the meteorological data in the entire study area (including a large portion of Middle East), in a 30 year period (1979-2008), is eloquent of a drought during the last 10 years of the period. In the second section, by means of the Aerosoal Index (AI) extracted from TOMS and OMI tools, it was... 

Urbanization and increase in impervious areas owing to building construction, pavements of streets, parking lots and sidewalks, amount of surface runoff in cities has been rose. One of the environmental problems of Tehran during the rainfall is the high polluted runoff flowing in the city and eventually transfers pollution to aquifers. So in order to decline the consequences of this polluted surface runoff, it is crucial to understand how the runoff and pollution form. One way of decreasing pollution in runoff is hiring swales attenuation potential. In this study, problems associated with runoff, particularly in relation to the formation, transformation and removal of pollutants from runoff... 

Groundwater resources are considered as important resources of fresh water specifically in arid and semi-arid regions like Iran. Urmia Lake (UL) basin is one of these regions where groundwater resources play an important role in supplying water and due to inappropriate water resources management during the last two decades it has faced serious problems, like declination of water level in UL. Groundwater and surface water form an integrated system in the UL basin and have a mutual effect on each other. Hence, any improvement in exploitation of aquifers in that region could benefit UL water demand management. Appropriate water resources management in Miandoab plain which transfer almost 50... 

Due to water resources restriction and increase in water demand, optimum use of existing available resources is more essential. This needs accurate prediction of streamflow with lag time from one to several months. In recent decades identification of long term climate variables as predictors of hydrological process has made considerable evolution in climatic predictions and several studies have been made in this field. In this research streamflow volume of Dez Dam in dry season (April to August) has been predicted by using multiple regression models and considering seasonal rainfall data, climate indices and ocean-atmospheric variables including surface temperature of adjacent seas and... 

Structural best management practices (BMPs) are often used to mitigate the impact of storm water runoff on receiving waters. Vegetative filter strips (VFS) are an example of a structural BMP that has been used to treat storm water and highway runoff. In this study (the first in Iran), field-quality data were collected from a native VFS treating urban runoff in North of Tehran. At first field data were used to test the design concepts of the VFS treatment train and to modify and calibrate simulation model for evaluating the impact of physical factors such as slope, type of vegetation and impermeable surface on sediment removal then more field data were used to evaluate and modify the... 

Chitgar Lake, lake located in the north-west of Tehran City, Iran, is an artificial and recreational lake. The total area and volume of this lake are about 132 hectares and 6.9 million cubic meters, respectively. According to the increased temperature, the lake ecosystem is faced with problems such as augmentation of vermin, frogs and algae in the lake area. Qualitative measurements of 59 well taken samples from March 2013 to June 2014, demonstrate that ratio of total nitrogen to total phosphorus is in the range of 21 to 82 with an average of 42. Consequently, phosphorus is the restricting factor for eutrophication in this lake. In this study, by scrutinizing various scenarios, factors... 

Construction of some structures including parks, bridges and leading walls conducted on the rivers in urbanization leads to the change in the form of the rivers and consequently the change in the hydraulic.The response of river to these changes which are in the form of changes in morphologic features seems to pose some threats such as flood, damage to the buildings located on the route, weakening the bridge of highways and aggradation and degradation of the ecosystem. Kan river, one of the biggest urban rivers in the mega city of tehran, has had some changes such as resort purposes, canalization, the change of slip and roughness and intersection with different bridges during recent... 

Urmia Lake is a strong electrolyte containing various salts, with a thermodynamic identity. Changes in the temperature and volume of lake water cause a change in the concentration of ions in this brine as well as the composition and precipitation of salts in the lake. As a result of these changes, the thermodynamic properties of brine are also changed. The purpose of this study was to investigate the effect of mixing the rivers entering the lake and calculate and analyze the changes in the quality and hydrogeochemical characteristics of Urmia Lake and the amount of precipitation and dissolution of the main minerals in Urmia Lake during the period of 2007-2013 per month. For this purpose,... 

Nowadays, urban storm water management and wastewater reuse are of main concerns of urban managers. Changes in surface specifications such as imperviousness, manning coefficient, pollutant buildup … during catchment transformation of land use from natural to urban can lead to undesirable change in quality and quantity of catchment's outlet runoff that could cause serious damage to receiving bodies. In recent decades, urban designing's approach has been using detention and quality improvement systems in order to manage urban runoff. Urban runoff and its treatment system (BMP: best management practices) and urban lake (as a receiving body) have been modeled in this research. Velenjak stream's... 

Urbanization increases impervious surfaces and therefore reduces land permeability. As a result, higher amount of runoff is produced which leads to environmental degradation and economic loss. Use of pervious/permeable pavements is an efficient approach to reduce runoff volume and improve the quality. In this study, different design methods of pervious/permeable surface are first described using structural and hydrological modules. Then, a software program for pervious/permeable surface design is put forth. Supported by various available design methods (focusing on pervious surfaces in Iran), the software employs structural, hydrological, economic (cost estimation) and qualitative... 

Each country needs water for growing and developing. Water is necessary not only for expansion of cities and industries but also for agricultural development. Agriculture alone uses more than 90 percent of available water in our country. Water limitation and improper and noneconomic use of water are the main factors that limit agricultural development and food production in Iran. So taking appropriate decisions on this issue is necessary to optimize water use. Continuous assessment of water use at different levels in the basin, field and irrigation network is necessary for determining the current status and knowing its strengths and weaknesses and finding practical solutions to improve all... 

Desiccation of different salty lakes around the world has been considered as one of the most critical environmental events. Gradual desiccation of the Lake Urmia and retreatment of its shoreline with respect to ecological level (1274.1 meters) have resulted in new hotspots for dust outbreaks, especially in east and south-east peripheries, which were previously under water. These areas, part of which are salty, are now exposed to open air and susceptible to wind-erosion. Soil moisture, as one of the most important parameters for dust prevention, determines the threshold friction wind speed over playa because it increases the cohesion between soil particles. Therefore, compared with dry soil,...