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871.
ABSTRACT A methodology for predicting the spatial and temporal levels of conservative water quality constituents within a multibasin water resource system is presented. Dissolved solids, sulfates, and chlorides are the constituents used during this investigation; however, any other conservative ion or mineral can be incorporated into the simulation model. The methodology is tested on the proposed Texas Water System. The water quality model, QNET-I, utilizes monthly canal and river flows and reservoir storage levels calculated by the Texas Water Development Board's systems simulation model. Discharge-concentration relationships are developed for each source of water in the system, including significant waste-water discharges. Reservoirs in the system are assumed to be completely mixed with respect to conservative constituents. A mass balance analysis is performed for each node and each month during the simulation period. The output from the water quality simulation is a table of the concentrations of the conservative water quality constituents at each demand point in the system and in each reservoir and canal for every month the system is in operation. The desired quality of the water at the demand locations is used to determine the economic utility of transporting and mixing water from various sources.  相似文献   
872.
873.
ABSTRACT .Operating rule procedures are developed for the optimal use of desalination in conjunction with surface water impoundments. Results obtained from the use of hill-climbing and dynamic programming methods are compared. Benefits to be obtained from the integrated use of desalination are demonstrated through a case study for the Barcelona area of Spain.  相似文献   
874.
ABSTRACT. In 1970, the Canadian Federal Government passed the Canada Water Act which provides for a co-operative federal-provincial approach to water resource management. The purpose of this paper is to outline our definition of comprehensive planning and the approach being taken under the new legislation. Two basic premises underly the definition. They are that resource management consists of an array of problems and that the prime function of planning is to provide information for decision making. The definition of comprehensive planning is embodied in a general statement and a set of principles. The principles define the approach that should be taken to provide adequate information for decision making in today's complex environment. A brief resume of the jurisdictions for water management in Canada leads to a discussion of a joint federal-provincial comprehensive study of the Qu'Appelle River Basin in Southern Saskatchewan. The basin and the study are described briefly. This is followed by an outline of the economic and social considerations which are being incorporated into the comprehensive planning study for the basin.  相似文献   
875.
The Miami Conservancy District was organized shortly after the disastrous flood of March 1913 to provide flood protection to municipalities along the Great Miami River. The District system is a classic solution which was entirely locally financed and is now operated and maintained by special benefit assessments on 45,000 parcels of property, 9 cities and 5 counties.  相似文献   
876.
ABSTRACT: Extension of basic step methods of backwater computation to reaches of finite length is examined. Accuracies of commonly accepted hydraulic loss equations under particular water surface profile conditions are compared. Simulation of energy lines within a reach by parabolic curves is found to minimize error provided orientation of the axis of the parabola is selected in accordance with prevailing hydraulic conditions. Theoretical basis for an index reach length beyond which single-step computation from end to end of the reach must be in error is developed. Reduction of this reach length by suitable factors tailored to hydraulic conditions yields a mathematically defined allowable reach length for backwater computation. When reach length does not exceed this allowable reach length, no significant error may be detected. Automatic insertion of synthetic cross sections interpolated between surveyed cross sections when these are inadvertently spaced too far apart enables computation to proceed. This device is error-free for prismatic channls but may introduce error for irregular natural channels. Preliminary trials indicate that results so obtained may be accepted provided the fall in the original reach does not exceed from one to two feet. When this is exceeded, additional cross sections should be surveyed.  相似文献   
877.
878.
The hydrocarbons contents (n-alkanes, polycyclic aromatic hydrocarbons) were determined in the sea urchin Arbacia lixula. Multivariate data analysis as principal component analysis, factor analysis and, cluster analysis were applied to elucidate sources of pollution. PCA and FA were performed to establish the relationships between variables (hydrocarbons), samples (sea urchin) and sources of pollution.  相似文献   
879.
Uptake and fate of TNT and RDX by three aquatic and four wetland plants were studied using hydroponic, batch, incubations in explosives-contaminated groundwater amended with [U-14C]-TNT or [U-14C]-RDX in the laboratory. Substrates in which the plants were rooted were also tested. Plants and substrates were collected from a small-scale wetland constructed for explosives removal, and groundwater originated from a local aquifer at the Milan Army Ammunition Plant. This study demonstrated rapid uptake of [U-14C]-TNT derived 14C, concentration at the uptake sites and limited transport in all plants. Per unit of mass, uptake was higher in submersed than in emergent species. Biotransformation of TNT had occurred in all plant treatments after 7-day incubation in 1.6 to 3.4 mg TNT L-i, with labeled amino-dinitrotoluenes (ADNTs), three unidentified compounds unique for plants, and mostly polar products as results. Biotransformation occurred also in the substrates, yielding labeled ADNT, one unidentified compound unique for substrates, and polar products. TNT was not recovered by HPLC in plants and substrates after incubation. Uptake of [U-14C]-RDX derived 14C in plants was slower than that of TNT, transport was substantial, and concentration occurred at sites where new plant material was synthesized. As for TNT, uptake per unit of mass was higher in submersed than in emergent species. Biotransformation of RDX had occurred in all plant treatments after 13-day incubation in 1.5 mg RDX L-1, with one unidentified compound unique for plants, and mostly polar products as results. Biotransformation had occurred also in the substrates, but to a far lower extent than in plants. Substrates and plants had one unidentified 14C-RDX metabolite in common. HPLC analysis confirmed the presence of RDX in most plants and in three out of four substrates at the end of the incubation period.  相似文献   
880.
Different strategies of multivariate analysis of metals concentrations (Mn, Fe, Ni, V, Co, Cu, Cd, Hg, Pb, Na, K) in mussel samples from different spanish markets are used to interpret a data base and identify differences between species and origin of the samples. Principal Component Analysis and Potential curves are applied to properly classify unknown samples from representative mussels samples (Mytilus edulis and Perna canaliculus). Also, Principal Components Analysis is used as display method to visualize the relation between the variables and objects of interest.  相似文献   
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