Sharif Digital Repository

River water quality monitoring using traditional water sampling and laboratory analyses is expensive and time-consuming. The application of artificial neural network (ANN) models to simulate water quality parameters is cost-effective, quick, and reliable. This study provides two methods of mathematical and ANN modeling to simulate and forecast five important river water quality indicators (DO, TDS, SAR, BOD5, HCO3) correlated with variables such as EC, temperature, and pH which can be measured easily and almost with no cost. The mathematical method is based on polynomial fitting with least square method and the neural network model was developed using a feed-forward algorithm. The 35 years’... 

the development and enlargement of city structure has caused the environmental problems on watershed of Latian dam which is one of the drinking water resourses of Tehran. The enlargement of Lavasan town and existence of an army garrison that it's effluents of treatment plant discharge to this river necessitate a water quality surveillance in entrance area of the dam. The present research includes the survey of this river's self-purification in the mentioned-above area. Numerical analysis is used in different methods to explain self- purification. Frist, we have the numerical analysis and analytical methods for a known sample in order to determine the accuracy and deviation between two... 

This paper describes a simple and low-cost test strip for on-site monitoring of methiocarb insecticide. Hydrophilic filter paper soaked in agarose solution was bounded by hydrophobic solid wax and then was coated with unmodified gold nanoparticles (AuNPs). AuNPs aggregation caused by methiocarb served as colorimetric response. We demonstrated detection capability of methiocarb both in solution- and substrate-based sensor. A good linear relationship was obtained between the colorimetric response and the concentration of methiocarb ranging from 20 to 80 ng mL -1 with a limit of detection of 5 ng mL -1. Excellent selectivity toward methiocarb was observed among various pesticides and cationic... 

This Regular evaluation and analysis of river quality helps accurate management to reach acceptable quality. In this study, water quality indices (WQI) method applied to evaluate quality of Jajrood River which is one of the main sources of Tehran drinking water. It helps to subsidize management actions in Jajrood watershed. Sampling carried out for 9 years during 2001-2010 in 10 stations along the river in wet and dry stations to identify water quality and the main source of pollution. Results show water quality in all stations classifies as medium according to National Sanitation Foundation (NSF) and water quality index in wet season is better than the corresponding value in dry seasons.... 

Various urban, industrial, and agricultural pollutions discharge more than river self-purification potential damages river ecosystem and increases water treatment costs. As different decision-makers and stakeholders are involved in the water quality management in river systems, a new bankruptcy form of the game theory is used to resolve the existing conflict of interests related to waste load allocation in downstream river. The river restoration potential can allocate to the conflicting parties with respect to their claims, by using bankruptcy solution methods. In this research, dischargeable pollution loads to Karun River are determined by pollution sources in various scenarios using... 

Dam construction in arid and semiarid regions is generally related to the risk of increased salinity, due to water passage in contact with salty formations. Hence, it is important to take reservoir thermal and salinity stratification into account in operational rules. In the present study, a simulation–optimization model was developed to determine the amount of water release from various outlets to discharge the brine from hypolimnion layer considering the downstream water quality limitations. The most appropriate time, rate, and concentration to release brine were determined based on water consumption conditions and downstream water demand and river ecology characteristics. The proposed... 

Recently, remote sensing considered as important tool in studies of water quality issues. The Aras River flows across a transboundary basin in northern Iran. In this study, the aim is to model the water quality parameters (WQPs) using remote sensing and an artificial neural network (ANN), which is a new method proposed to find WQPs based on multivariate regression approaches. The relationship between WQPs and digital data from the Sentinel-2 satellite was determined to estimate and map the WQPs in this river. Using the field data and digital image data, the obtained results show that multivariate regression approaches and high-resolution remote sensing could monitor and predict the... 

Various urban, industrial, and agricultural pollutions discharge more than river self-purification potential damages river ecosystem and increases water treatment costs. As different decision-makers and stakeholders are involved in the water quality management in river systems, a new bankruptcy form of the game theory is used to resolve the existing conflict of interests related to waste load allocation in downstream river. The river restoration potential can allocate to the conflicting parties with respect to their claims, by using bankruptcy solution methods. In this research, dischargeable pollution loads to Karun River are determined by pollution sources in various scenarios using... 

Non-point source pollution of phosphorus (P) is a primary cause of eutrophication of aquatic ecosystems, and poses a persistent management challenge due to the dynamic and poorly understood processes controlling the transport and transformation of P at the watershed scale. We examined phosphorus inputs, retention, and riverine losses in 62 diverse watersheds that included a wide range of land cover and use (minimally disturbed to human dominated) and human P inputs in Minnesota, USA. Fertilizer inputs from row crop cultivation were the dominant source of P to agricultural watersheds. A large majority of P inputs was retained in watershed soils or removed in agricultural products. However,... 

We revisit and shed light on the millennium-old hydrogeology textbook The Extraction of Hidden Waters by the Persian mathematician and engineer Karaji. Despite the nature of the understanding and conceptualization of the world by the people of that time, ground-breaking ideas and descriptions of hydrological and hydrogeological perceptions such as components of hydrological cycle, groundwater quality and even driving factors for groundwater flow were presented in the book. Although some of these ideas may have been presented elsewhere, to the best of our knowledge, this is the first time that a whole book was focused on different aspects of hydrology and hydrogeology. More importantly, we... 

Lake Urmia is a thalassohaline ecosystem. It is an extremely simple ecological pyramid. This makes it a very sensitive ecosystem. This ecosystem has been facing various threats regarding the amount of water released from the associated basin. To calculate the lake water requirement with an ecological approach, we identified three variables: ecology, water quality, and water quantity indices as environmental indicators. The ecological index represented by Artemia urmiana is considered as an independent variable; while, the water quality index represented by concentration of NaCl, and the water quantity index represented by water elevation are regarded as dependent variables. The salinity... 

Thermal stratification accompanied by a release of nutrients from sediment is a serious problem for the management of water quality. Water aeration and mixing technology can be widely used to control endogenous pollution and algae growth in reservoirs and lakes by water quality managers. In this research, a diffuser aeration system, was installed in a water column, in the Mamloo stratified Reservoir; and the impact of artificial aeration was brought under extensive assessment in relevance with the qualitative and biological parameters of the water, during the preliminary 6 d of aeration. The results showed that the thermal stratification was remarkably disturbed. After aeration, the amount... 

Water quality is one of the most important factors contributing to a healthy life. From the water quality management point of view, TDS (total dissolved solids) is the most important factor and many water developing plans have been implemented in recognition of this factor. However, these plans have not been perfect and very successful in overcoming the poor water quality problem, so there are a good volume of related studies in the literature. We study TDS and the water flow of the Karoun river in southwest Iran. We collected the necessary time series data from the Harmaleh station located in the river. We present two Univariate Seasonal Autoregressive Integrated Movement Average (ARIMA)... 

All of the man-made objects and anthropogenic activities related to the oil industries in water bodies (e.g. drilling, equipment installation, construction of oil platfonns and especially oil spillages) have enviromnental impacts on water ecosystems. The assessment of oil field operations and oil platfonns impacts on water quality have become a necessity throughout the world. Phytoplanktons have the lowest trophic level in water enviromnent; therefore the life of all of the other marine animals is highly relevant to phytoplanktonic population. Hence it seems necessary to monitor the spatiotemporal effects of different activities and events, related to oil industries on phytoplanktons.... 

Efficient environmental management calls for the consideration of multiple pollutants, for which two main types of transferable discharge permit (TDP) program have been described: separate permits that manage each pollutant individually in separate markets, with each permit based on the quantity of the pollutant or its environmental effects, and weighted-sum permits that aggregate several pollutants as a single commodity to be traded in a single market. In this paper, we perform a mathematical analysis of TDP programs for multiple pollutants that jointly affect the environment (i.e., interactive pollutants) and demonstrate the practicality of this approach for cost-efficient maintenance of...