971 resultados para Water quality biological assessment


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"Prepared for the Illinois Environmental Protection Agency."

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"IEPA/WPC/89-275"--Cover.

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Although Microcystis-based toxins have been intensively studied, previous studies using laboratory cultures of Microcystis strains are difficult to explain the phenomenon that microcystin concentrations and toxin variants in natural blooms differ widely and frequently within a short-term period. The present study was designed to unravel the mechanisms for the frequent variations of intracellular toxins related to the differences in cyanobacterial colonies during bloom seasons in Lake Taihu, China. Monitoring of Microcystis colonies during warm seasons indicated that the variations in microcystins in both concentrations and toxin species were associated with the frequent alteration of Microcystis colonies in Lake Taihu. High concentration of microcystins in the blooms was always associated with two Microcystis colonies, Microcystis flos-aquae and Microcystis aeruginosa, whereas when Microcystis wesenbergii was the dominant colonial type, the toxin production of the blooms was low. Additionally, environmental factors such as temperature and nutrition were also shown to have an effect on the toxin production of the blooms, and may also potentially influence the Microcystis species present. The results of the present study provides insight into a new consideration for quick water quality monitoring, assessment and risk alert in cyanobacterium- and toxin-contaminated freshwaters, which will be beneficial not only for water agencies but also for public health. (C) 2009 Elsevier Ltd. All rights reserved.

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Due to growing urbanization and industrialization, the environment is suffering from pollution of rivers, degradation of soils and deteriorated air quality. Quality indices appear to be useful to evaluate the conditions of these media. The aim of this study was the development of a water quality index using a fuzzy inference system, since such an approach has proved advantageous in addressing problems that are subjective by nature or for which the data are uncertain. The methodology employed was based on this inference system, and considered the nine water quality parameters employed by CETESB (Companhia de Tecnologia de Saneamento Ambiental, São Paulo, Brazil) to evaluate water quality. After assessment of the data using the index, a comparison was made with the WQI (Water Quality Index), which is used for the monitoring of various water bodies, including in the study region. The results obtained using the index developed on the basis of fuzzy inference were found to be more useful than those derived from the method currently used by CETESB, since losses and/or omissions concerning individual parameters were minimized. © 2010 IEEE.

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According to Section 305(b) of the Clean Water Act (i.e. a generic name that refers to the Federal Water Pollution Control Act of 1972, the Clean Water Act of 1977, and subsequent amendments) and guidance provided by the United States Environmental Protection Agency (USEPA), each state must prepare and submit annually to the U.S. Congress and the USEPA report that describes the resource quality of the surface waters of the state. Every other year, this report, commonly referred to as the "305(b) report," must be provided in written form, whereas in alternate years each state may submit an electronic database to meet the reporting requirement. In the 305(b) report, states must also explain how they determined the resource quality of the waters of the state in terms of the degree to which predefined beneficial uses of those waters are supported. Also, in the 305(b) report when any designated use for any water body is not fully supported, the state must report potential reasons for the impairment. Herein, is explained how the Illinois Environmental Protection Agency determines the resource quality of Illinois streams, inland lakes, and Lake Michigan.

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This executive summary report summarizes the results of an alternative evaluation and preliminary design study for improvements to, or removal of, the Glen D. Palmer Dam in Yorkville, Illinois. This study was conducted to recommend the best method of improving the hydraulic conditions at the downstream face of the dam, reconnect the river with respect to fish movement, and provide safe canoe passage through the dam site. The recommended alternative was developed by working with a Citizen Advisory Committee to involve the public throughout the study.

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The first bilateral study of methods of biological sampling and biological methods of water quality assessment took place during June 1977 on selected sampling sites in the catchment of the River Trent (UK). The study was arranged in accordance with the protocol established by the joint working group responsible for the Anglo-Soviet Environmental Agreement. The main purpose of the bilateral study in Nottingham was for some of the methods of sampling and biological assessment used by UK biologists to be demonstrated to their Soviet counterparts and for the Soviet biologists to have the opportunity to test these methods at first hand in order to judge the potential of any of these methods for use within the Soviet Union. This paper is concerned with the nine river stations in the Trent catchment.

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In recent collaborative biological sampling exercises organised by the Nottingham Regional Laboratory of the Severn-Trent Water Authority, the effect of handnet sampling variation on the quality and usefulness of the data obtained has been questioned, especially when this data is transcribed into one or more of the commonly used biological methods of water quality assessment. This study investigates if this effect is constant at sites with similar typography but differing water quality states when the sampling method is standardized and carried out by a single operator. An argument is made for the use of a lowest common denominator approach to give a more consistent result and obviate the effect of sampling variation on these biological assessment methods.

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"Prepared for the Illinois Environmental Protection Agency."

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"Prepared for the Illinois Environmental Protection Agency."

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"Prepared for the Illinois Environmental Protection Agency."