Dissolved oxygen concentrations in the lower reaches of the Tualatin River in northwest Oregon are the result of many processes. Temperature imposes a seasonal signal through the solubility of oxygen in water. Streamflow determines the travel time through the system and affects the amount of oxygen consumed via processes such as ammonia nitrification and the decomposition of organic material in...

background: the spread of urbanization in floodplains as well as increase of industrial and agricultural activities in river discharges may lead to water pollution by physical, chemical and biological pollutants. one of the major concerns in monitoring the water resources system is indentifying major quality parameters and determining a relationship between physical and chemical parameters. thi...

The objective of this study was to evaluate the treatment efficiency of a gravel contact oxidation treatment system which was newly constructed under the riverbed of Nan-men Stream located at the Shin Chu City of Taiwan. The influent and effluent water samples were taken periodically for the analyses of pH, temperature, dissolved oxygen, total suspended solids, five-day biological oxygen demand...

wastewater contains many organic and inorganic contaminants that can cause serious damage to the environment and health of people, therefore, they have to be eliminated before being downloaded into sensitive areas. different methods of wastewater purification have been used for contaminants removal. however, they present some technical and economic limitations. thus, new methods of nutrients re...

aims: textile wastewaters are the most important health and environmental problems in kashan. this research was aimed to compare the poly aluminum chloride and chlorinated cuprous efficiency for removal of chemical oxygen demand (cod) and color from kashan textile industries company wastewater. materials & methods: this experimental bench scale study in a batch system was conducted on 20 compos...

anaerobic digestion is the breakdown of biodegradable organic material by microorganisms in the absence of oxygen or in an oxygen-starved environment.this technology is superior to the landfilling and also the aerobic composting. the aim of the present study was to examine whether the effluent volatile fatty acids from the anaerobic acidogenesis of the food waste can be used du to its high valu...

background: survey of pollution and evaluation of water quality in rivers with oregon water quality index (owqi) and gis are effective tools for management of the impact of environmental water resources. the information in calculating the wqi of moradbeik river allowed us to take our tests results and make a scientific conclusion about the quality of water. gis can be a powerful tool for develo...