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1.
Can J Microbiol ; 67(11): 813-826, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34171204

RESUMO

Microbial communities are an important aspect of overall riverine ecology; however, appreciation of the effects of anthropogenic activities on unique riverine microbial niches, and how the collection of these samples affects the observed diversity and community profile is lacking. We analyzed prokaryotic and eukaryotic communities from surface water, biofilms, and suspended load niches along a gradient of oil sands-related contamination in the Athabasca River (Alberta, Canada), with suspended load or particle-associated communities collected either via Kenney Sampler or centrifugation manifold. At the phylum level, different niche communities were highly similar to each other and across locations. However, there were significant differences in the abundance of specific genera among the different niches and across sampling locations. A generalized linear model revealed that use of the Kenney Sampler resulted in more diverse bacterial and eukaryotic suspended load community than centrifugal collection, though suspended load communities collected by any means remained stably diverse across locations. Although there was an influence of water quality parameters on community composition, all sampled sites support diverse bacterial and eukaryotic communities regardless of the degree of contamination, highlighting the need to look beyond ecological diversity as a means of assessing ecological perturbations, and consider collecting samples from multiple niche environments.


Assuntos
Rios , Poluentes Químicos da Água , Alberta , Monitoramento Ambiental , Eucariotos/genética , Mineração , Campos de Petróleo e Gás , Poluentes Químicos da Água/análise
3.
Environ Sci Technol ; 48(5): 2660-70, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24446583

RESUMO

The objective of this study was to identify chemical components that could distinguish chemical mixtures in oil sands process-affected water (OSPW) that had potentially migrated to groundwater in the oil sands development area of northern Alberta, Canada. In the first part of the study, OSPW samples from two different tailings ponds and a broad range of natural groundwater samples were assessed with historically employed techniques as Level-1 analyses, including geochemistry, total concentrations of naphthenic acids (NAs) and synchronous fluorescence spectroscopy (SFS). While these analyses did not allow for reliable source differentiation, they did identify samples containing significant concentrations of oil sands acid-extractable organics (AEOs). In applying Level-2 profiling analyses using electrospray ionization high resolution mass spectrometry (ESI-HRMS) and comprehensive multidimensional gas chromatography time-of-flight mass spectrometry (GC × GC-TOF/MS) to samples containing appreciable AEO concentrations, differentiation of natural from OSPW sources was apparent through measurements of O2:O4 ion class ratios (ESI-HRMS) and diagnostic ions for two families of suspected monoaromatic acids (GC × GC-TOF/MS). The resemblance between the AEO profiles from OSPW and from 6 groundwater samples adjacent to two tailings ponds implies a common source, supporting the use of these complimentary analyses for source identification. These samples included two of upward flowing groundwater collected <1 m beneath the Athabasca River, suggesting OSPW-affected groundwater is reaching the river system.


Assuntos
Monitoramento Ambiental , Água Subterrânea/análise , Resíduos Industriais/análise , Campos de Petróleo e Gás/química , Poluição por Petróleo/análise , Poluentes Químicos da Água/análise , Alberta , Cromatografia Gasosa-Espectrometria de Massas , Dióxido de Silício/análise , Espectrometria de Fluorescência , Espectrometria de Massas por Ionização por Electrospray
4.
J Environ Monit ; 14(12): 3118-28, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23103968

RESUMO

The assessment of the adequacy of sampling locations is an important aspect in the validation of an effective and efficient water quality monitoring network. Two geostatistical approaches (e.g., kriging and Moran's I) are presented to assess multiple sampling locations. A flexible and comprehensive framework was developed for the selection of multiple sampling locations of multiple variables which was accomplished by coupling geostatistical approaches with principal component analysis (PCA) and fuzzy optimal model (FOM). The FOM was used in the integrated assessment of both multiple principal components and multiple geostatistical approaches. These integrated methods were successfully applied to the assessment of two independent water quality monitoring networks (WQMNs) of Lake Winnipeg, Canada, which respectively included 14 and 30 stations from 2006 to 2010.


Assuntos
Lógica Fuzzy , Modelos Estatísticos , Análise de Componente Principal , Poluentes da Água/análise , Qualidade da Água/normas , Manitoba , Modelos Químicos , Análise Espacial , Poluição da Água/estatística & dados numéricos , Abastecimento de Água
5.
Artigo em Inglês | MEDLINE | ID: mdl-17616873

RESUMO

Several oil sands mines and refineries are currently recovering oil from the Athabasca River region near Fort McMurray, Alberta. Planning and construction of additional oil sands mines are in various stages of completion. Due to environmental concerns for aquatic life in areas downstream from current and future oil sands activities, surveys were conducted between 1998 and 2000 to determine whether the quality of water and sediments in tributaries of the Athabasca River are affected by flowing through reaches with exposure to natural oil sand deposits. This paper presents the results for metals in bed and suspended sediments collected from the Mackay, Steepbank, and Ells rivers during those surveys. The suspended sediments had a clay content (n = 7) ranging from 36.2% to 65.0%, while bed sediments, which consisted of a predominant sand fraction, had percent clay (n = 39) ranging from 0.0% to 38.1%. A Mann-Kendall non-parametric analysis to assess the longitudinal trend of the metals in the bed sediments found no significant (alpha = 0.05) downstream trend in the Mackay or Steepbank rivers; however, the Ells River displayed a generally decreasing tend from upstream to downstream. The results provide no indication that metal concentrations in the bed sediments and/or suspended sediments of the Mackay, Steepbank, and Ells rivers increase significantly as the three tributaries flow through reaches that have natural oil sand exposures (McMurray Formation).


Assuntos
Sedimentos Geológicos/química , Metais/análise , Poluentes Químicos da Água/análise , Alberta , Tamanho da Partícula
6.
Environ Monit Assess ; 113(1-3): 71-85, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16525883

RESUMO

The Northern River Ecosystem Initiative (NREI), 1997-2004, has provided new scientific knowledge in response to specific recommendations from its predecessor, the Northern River Basins Study (NRBS), 1990-1996. The two initiatives together provide a remarkable body of science which is, and will continue to be, used by resource managers responsible for economic and environmental sustainability in the northern watersheds of Alberta. The NREI focused its investigative efforts on improving our understanding related to ecological considerations of changes in river flow, effect of climate change on flow, ecological responses to pollution and cumulative effects, vulnerability of drinking water quality, and to a lesser degree, wildlife (birds) response to large scale changes within the watersheds. Key findings are briefly presented in this paper and discussed in greater detail in the other NREI papers included in this. Commensurate with the undertakings of NREI, provincial and territorial governments, First Nation and Métis communities, and other administrative organizations such as the Mackenzie River Basin Board, undertook policy, regulatory, and watershed initiatives towards achieving sustainability and providing reliable drinking water quality.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Monitoramento Ambiental/métodos , Poluição Ambiental/prevenção & controle , Desenvolvimento de Programas , Rios , Alberta , Abastecimento de Água/normas
7.
Artigo em Inglês | MEDLINE | ID: mdl-15663297

RESUMO

At present, there are two large industrial plants recovering oil from the lower Athabasca oil sands area and there are plans for several more mines in the area. There are environmental concerns for aquatic life in areas downstream of current and future oil sands activities. To assess and predict potential impacts of industrial activities, it is important to separate impacts from those produced by naturally occurring oil sands deposit. Studies were therefore conducted to determine whether the water quality of tributaries to the Athabasca River, which have not been impacted by anthropogenic activities, is affected by inorganic constituents resulting from flowing through reaches with natural oilsands deposit. Three tributaries, Steepbank River, Mackay River, and Ells River at upstream and downstream locations on each stream were investigated during four surveys from 1998 to 2000. In addition to some physical parameters such as pH, conductance and hardness and the major ions (calcium, magnesium, sodium, potassium, bicarbonate, chloride, sulfate, and silicates), seventeen trace metals were investigated. Some of these metals, especially iron and manganese, were of high concentrations and in some instances, particularly in a survey conducted during the spring freshets in April 1999, exceeded guidelines for the protection of aquatic life. The observed concentrations of metals seem to be of natural origin and can be used as base-line data for future assessment of anthropogenic activities in the oil sand region.


Assuntos
Metais/análise , Mineração , Petróleo , Poluentes Químicos da Água/análise , Alberta , Bicarbonatos/análise , Cloretos/análise , Monitoramento Ambiental , Metais/normas , Rios/química , Silicatos/análise , Dióxido de Silício , Sulfatos/análise , Poluentes Químicos da Água/normas
8.
Artigo em Inglês | MEDLINE | ID: mdl-15137690

RESUMO

The Athabasca Oil Sands is one of the four natural oil sands deposits in Northern Alberta, Canada, and are by far the largest oil sand deposit in North America, covering an area of 46,000 km2. Sediment samples were collected from the bed and bank of several tributaries that have naturally occurring exposures of oil sand material. Oil sand deposited along the lower Athabasca River, more than 100 km downstream of naturally occurring oil sand exposures, were also sampled. The levels of alkylated polycyclic aromatic hydrocarbons (PAHs) in samples collected from these various locations ranged from not detected to almost 50 ppm. Using dibenzothiophene/chrysene (C2/D2 vs. C3/D3) double ratio plots, it is possible to approximate the relative degree of degradation or weathering of the PAHs from these various sediment deposits along the lower Athabasca River and its tributaries. Similarly a plot of dibenzothiophene/phenanthrene (D2/P2 vs. D3/P3) indicate the possible origins of the oil. A combination of these plots, D3/P3 vs. D3/C3, was particularly useful in identifying weathering characteristics of different sources of the oil. Comparison of alkylated PAH distributions between the lower Athabasca River and the tributaries show slight differences consistent with different petrogenic sources and/or different weathering patterns.


Assuntos
Sedimentos Geológicos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Alberta , Monitoramento Ambiental , Fenômenos Geológicos , Geologia , Rios
9.
Environ Monit Assess ; 67(1-2): 195-215, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11339699

RESUMO

There are millions of small isolated wetlands in the semi-arid Canadian prairies. These sloughs' are refuges for wildlife in an area that is otherwise intensively used for agriculture. They are particularly important as waterfowl habitat, with more than half of all North American ducks nesting in prairie sloughs. The water levels and ecology of the wetlands are sensitive to atmospheric change and to changes of agricultural practices in the surrounding fields. Monitoring of the hydrological conditions of the wetlands across the region is vital for detecting long-term trends and for studying the processes that control the water balance of the wetlands. Such monitoring therefore requires extensive regional-scale data complemented by intensive measurements at a few locations. At present, wetlands are being enumerated across the region once each year and year-round monitoring is being carried out at a few locations. The regional-scale data can be statistically related to regional climate data, but such analyses cast little light on the hydrological processes and have limited predictive value when climate and land use are changing. The intensive monitoring network has provided important insights but it now needs to be expanded and revised to meet new questions concerning the effects of climate change and land use.


Assuntos
Clima , Conservação dos Recursos Naturais , Ecossistema , Movimentos da Água , Animais , Aves , Canadá , Monitoramento Ambiental/métodos , Previsões
10.
J Nurs Adm ; 30(5): 227-40, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10823176

RESUMO

OBJECTIVE: This study 1) identified the research evidence; 2) assessed the state-of-the-science surrounding hospital ownership, performance, and outcomes in acute care hospitals in the United States; and 3) identified measurable components of hospital performance and outcomes for the organization, patient, and community. BACKGROUND: As the size of the nonprofit sector decreases and the size of the for-profit sector increases, hospital ownership warrants examination. Most research has focused on either ownership and performance or ownership and outcomes, rather than the potential interaction of all three variables. METHODS: A comprehensive, computerized search of the healthcare research literature yielded 69 data-based references published between 1985 and 1999. Coding sheets were developed to abstract the articles. Analysis involved synthesizing the research evidence for each of the three major variables and their components. RESULTS: Hospital ownership has an impact on hospital performance in relation to system operations; costs, prices, and financial management practices; and personnel issues. Organizational outcomes are similar among hospital ownership types in relation to increasing administrative costs and overall mediocre efficiency. Organizational outcomes differ among hospital ownership types in relation to nursing staff mix and professional satisfaction. The association of hospital ownership with patient outcomes varies depending on the dimension measured. The evidence is mixed or inconclusive regarding hospital ownership and access to care, morbidity, and mortality. The association of hospital ownership and adverse events is consistently supported. Hospital ownership status has an impact on the type and magnitude of community benefits. Differences among the three hospital ownership types are minimized in a competitive market. CONCLUSIONS: This study reinforces the position that nurse researchers need to include hospital ownership as an important structural variable in their studies of hospital-based nursing. Examining the conceptual links between ownership, performance, and outcomes requires the integration of macro-level and micro-level theory.


Assuntos
Hospitais com Fins Lucrativos/organização & administração , Hospitais Públicos/organização & administração , Hospitais Filantrópicos/organização & administração , Avaliação de Resultados em Cuidados de Saúde , Propriedade , Relações Comunidade-Instituição , Eficiência Organizacional , Administração Financeira de Hospitais , Humanos , Pesquisa em Enfermagem/métodos , Gestão de Recursos Humanos , Estados Unidos
11.
Nurs Econ ; 15(5): 253-61, 264, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9362868

RESUMO

The authors present their findings following an exhaustive literature review of research on differentiated nursing practice (DNP) that used a number of tools to measure various aspects of DNP that are applicable across the health care delivery continuum. Issues related to DNP include: optimal nursing care, matching patient needs with nurse competencies, effective use of nursing resources, equitable compensation, career satisfaction, loyalty to employers, and enhanced prestige of the nursing profession. One 1992 Massachusetts study of a three-role oncology unit project (including patient care manager, clinical nurse, and patient care technician), showed positive change in five criteria including: standards of nursing care, actual care hours, average labor costs, job satisfaction and patient satisfaction. A 1990 Arizona study that included unit assistants concluded that DNP supported a decline in the use of supplemental staff and staff overtime which led to cost savings, and increases in the actual hours of care and nurse satisfaction.


Assuntos
Descrição de Cargo , Modelos de Enfermagem , Enfermeiros Administradores/organização & administração , Assistentes de Enfermagem/organização & administração , Recursos Humanos de Enfermagem Hospitalar/educação , Recursos Humanos de Enfermagem Hospitalar/organização & administração , Equipe de Enfermagem/organização & administração , Redução de Custos , Educação Técnica em Enfermagem , Bacharelado em Enfermagem , Humanos , Satisfação no Emprego
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