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Groundwater protection: the science and practice of land surface zoning
1995
Foster, S. | Skinner, A.C.
[Cultivation agreements: development of a tool to protection of the groundwater]
1999
Vangsgaard, C. | Schroeder, L.
Ecological indicators of water quality at the Arctic region: Critical levels of integrating impacts
1999
Moiseenko, T. (Kola Science Centre, Apatity (Russia))
Water Quality Assessment and Control: the Case of Italy
2001
Trisorio-Liuzzi, G. (Centre International de Hautes Etudes Agronomiques Méditerranéennes, Bari (Italy). Institut Agronomique Méditerranéen) | Hamdy, A.
Monitoring of Natural Hydrocarbon Release from Oilsands Deposits in a Canadian River Basin
2001
Headley, J. (National Water Research Centre, Cairo (Egypt)) | Tawfic, T. A.
Athabasca Oil Sands are found in the McMurray formation in the Athabasca River Basin in Northern Alberta, Canada. Monitoring studies conducted during 1998-1200, have indicated that there is a preponderance of oil sands-derived hydrocarbons, primarily PAHs, their C14 alkylated analogues, and biomarkers, in downstream sediment samples of the tributaries relative to the upstream samples. The relative composition of these hydrocarbons are diagnostic of a petrogenic source, and provides a fingerprint for characterization of biofilm samples, aquatic invertebrates, and sediments in northern rivers and tributaries. Results of GC-MS analyses of sediments, confirm that the tributaries passing through the Fort McMurray oil sands regions contain significant levels of naturally derived hydrocarbons (2-50 mg/g). Field activities in heavily impacted areas should therefore continue to emphasize the tributaries draining through oil sands deposits, as opposed to the main-stem of the Athabasca River where hydrocarbon levels are subject to dilution from high sedimentation rates.
Mostrar más [+] Menos [-]Abatement of Polar Organics in Natural Wetlands and Rivers. Analitycal Methods
2001
Headley, J. (National Water Research Centre, Cairo (Egypt)) | Tawfic, T. A.
Here are described three innovative and complementary methods for the characterization of polar organics in natural waters. A simple and rugged GC/MS procedure is shown to be well suited for the determination of sulfolane, (tetrahydrothiophene 1,1-dioxide, C4H8O2S; a water miscible chemical used in the sweetening of sour-gas) a compound that is known to be readily sequested by wetland vegetation. In contrast, LC/MS employing electrospray ionization is ideal for the quantification of two other classes of polar chemicals, namely (a) alkanolamines in vegetation and (b) mixtures of naphthenic acids in natural waters in oilsands regions of Northern Alberta, Canada. The modem techniques take advantage of quite simple extraction procedures, with no need for derivatization steps and exploit the polar nature of the chemicals to separate the analytes from high back ground non-polar components. For the alkanolamines, MS/MS is a prerequisite for obtaining diagnostic product ion scans of the molecular ion formed under soft-ionization conditions.
Mostrar más [+] Menos [-]Effect of Agricultural non-point Source Contaminants on Canadian Great Lakes Coastal Marshes
2001
Millette, J.A. (National Water Research Centre, Cairo (Egypt)) | Gutzman, D.W. | Gamble, D.S. | Bourgoin, B.P. | Mudroch, A. | Day, K. | Roshon, R.
As part of the Canadian Great Lakes Action Plan, the transport and effect of non-point source agricultural contaminants in wetlands were evaluated. Due to the broad scope of this study, the abilities of many individuals with different domains of expertise were employed. Stages of the study reported here include: 1) Survey of cropping and pesticide/fertilizer practices of farms in the selected watersheds; 2) Sampling and analysis of creek water and sediments for pesticides and other parameters; 3) Study of the reversible "loss" of pesticides by adsorptive and diffusive interaction with sediment particles; 4) Investigation of the effect of the agricultural contaminants on macrophytes and invertebrates. Among the findings of this work were the detection of some pesticides years after their last use as well as the presence of microorganisms, in all creek sediments tested, capable of rapidly and completely mineralizing atrazine.
Mostrar más [+] Menos [-]Water Quality Modelling
2001
El-Sayed, A. (Drainage Research Institute, Open Drainage Dept.)
Criteria for Protecting the Groundwater in Egypt
2001
Fadlelmawla, A.A.
The vitality, vulnerability, and evidence of pollution of the groundwater resources in Egypt are all necessitating the protection of the valuable resource. However, due to the historic dependence on Nile water and also due to the misconception of complete natural protection, major actions regarding regulation and protection were restricted to surface water. This situation resulted in total absence of a framework for the management of groundwater protection in the country. Experiences in Europe and the United States have shown that groundwater protection is technically a complex issue, requiring the preparation of a conceptual framework that addresses/identifies the main technical issues/tools of the protection. In this paper, a description of the criteria proposed for the groundwater protection management in Egypt is given. The criteria were prepared in the form of guidelines constituting of a conceptual framework and the technical tools needed for achieving the proposed framework. Along with the technical tools, recommendations regarding their application and other specific protection issues were given based on pilot area application.
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