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1.
Integr Environ Assess Manag ; 18(2): 428-441, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34331737

RESUMO

The desire to document and understand the cumulative implications of oil sands (OS) development in the ambient environment of northeastern Alberta has motivated increased investment and release of information in the past decade. Here, we summarize the knowledge presented in the theme-based review papers in this special series, including air, surface water, terrestrial biology, and Indigenous community-based monitoring in order to (1) consolidate knowledge gained to date, (2) highlight key commonalities and gaps, and (3) leverage this knowledge to assess the state of integration in environmental monitoring efforts in the OS region and suggest next steps. Among air, water, and land studies, the individual reviews identified a clear focus on describing stressors, including primarily (1) contaminant emission, transport, transformation, deposition, and exposure, and (2) landscape disturbance. These emphases are generally partitioned by theme; air and water studies focus heavily on chemical stressors, whereas terrestrial monitoring focuses on biological change and landscape disturbance. Causal attribution is often stated as a high priority objective across all themes. However, studies often rely on spatial proximity to attribute cause to industrial activity, leaving causal attribution potentially confounded by spatial covariance of both OS- and non-OS-related stressors in the region, and by the complexity of interacting pathways between sources of environmental change and ecological receptors. Geospatial and modeling approaches are common across themes and may represent clear integration opportunities, particularly to help inform investigation-of-cause, but are not a replacement for robust field monitoring designs. Cumulative effects assessment remains a common focus of regional monitoring, but is limited in the peer-reviewed literature, potentially reflecting a lack of integration among monitoring efforts beyond narrow integrated interpretations of results. Addressing this requires greater emphasis on a priori integrated data collection and integrated analyses focused on the main residual exposure pathways, such as atmospheric deposition. Integr Environ Assess Manag 2022;18:428-441. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).


Assuntos
Monitoramento Ambiental , Campos de Petróleo e Gás , Alberta , Ecotoxicologia , Monitoramento Ambiental/métodos
2.
Integr Environ Assess Manag ; 18(2): 333-360, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34676977

RESUMO

This review is part of a series synthesizing peer-reviewed literature from the past decade on environmental monitoring in the oil sands region (OSR) of northeastern Alberta. It focuses on atmospheric emissions, air quality, and deposition in and downwind of the OSR. Most published monitoring and research activities were concentrated in the surface-mineable region in the Athabasca OSR. Substantial progress has been made in understanding oil sands (OS)-related emission sources using multiple approaches: airborne measurements, satellite measurements, source emission testing, deterministic modeling, and source apportionment modeling. These approaches generally yield consistent results, indicating OS-related sources are regional contributors to nearly all air pollutants. Most pollutants exhibit enhanced air concentrations within ~20 km of surface-mining activities, with some enhanced >100 km downwind. Some pollutants (e.g., sulfur dioxide, nitrogen oxides) undergo transformations as they are transported through the atmosphere. Deposition rates of OS-related substances primarily emitted as fugitive dust are enhanced within ~30 km of surface-mining activities, whereas gaseous and fine particulate emissions have a more diffuse deposition enhancement pattern extending hundreds of kilometers downwind. In general, air quality guidelines are not exceeded, although these single-pollutant thresholds are not comprehensive indicators of air quality. Odor events have occurred in communities near OS industrial activities, although it can be difficult to attribute events to specific pollutants or sources. Nitrogen, sulfur, polycyclic aromatic compounds (PACs), and base cations from OS sources occur in the environment, but explicit and deleterious responses of organisms to these pollutants are not as apparent across all study environments; details of biological monitoring are discussed further in other papers in this special series. However, modeling of critical load exceedances suggests that, at continued emission levels, ecological change may occur in future. Knowledge gaps and recommendations for future work to address these gaps are also presented. Integr Environ Assess Manag 2022;18:333-360. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Alberta , Monitoramento Ambiental/métodos , Campos de Petróleo e Gás , Compostos Orgânicos
3.
Integr Environ Assess Manag ; 18(2): 388-406, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34510725

RESUMO

In the past decade, a large volume of peer-reviewed papers has examined the potential impacts of oil and gas resource extraction in the Canadian oil sands (OS). A large proportion focuses on terrestrial biology: wildlife, birds, and vegetation. We provide a qualitative synthesis of the condition of the environment in the oil sands region (OSR) from 2009 to 2020 to identify gaps and progress cumulative effects assessments. Our objectives were to (1) qualitatively synthesize and critically review knowledge from the OSR; (2) identify consistent trends and generalizable conclusions; and (3) pinpoint gaps in need of greater monitoring or research effort. We visualize knowledge and terrestrial monitoring foci by allocating papers to a conceptual model for the OS. Despite a recent increase in publications, focus has remained concentrated on a few key stressors, especially landscape disturbance, and a few taxa of interest. Stressor and response monitoring is well represented, but direct monitoring of pathways (linkages between stressors and responses) is limited. Important knowledge gaps include understanding effects at multiple spatial scales, mammal health effects monitoring, focused monitoring of local resources important to Indigenous communities, and geospatial coverage and availability, including higher attribute resolution in human footprint, comprehensive land cover mapping, and up-to-date LiDAR coverage. Causal attribution based on spatial proximity to operations or spatial orientation of monitoring in the region is common but may be limited in the strength of inference that it provides. Integr Environ Assess Manag 2022;18:388-406. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).


Assuntos
Monitoramento Ambiental , Campos de Petróleo e Gás , Alberta , Animais , Aves , Ecotoxicologia
4.
Neotrop. ichthyol ; 12(1): 133-143, Jan-Mar/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-709816

RESUMO

Bonito, in Mato Grosso do Sul State, is an important destination for ecotourism in Brazil and the main challenge of sustainable ecotourism here has been to accommodate and adjust the increase of tourism without compromising the ecological integrity of the local ecosystems. In this study we aimed to assess the environmental impact of ecotourism on the fish fauna of Sucuri River in Bonito by integrating ecological, behaviour and physiological criteria and using the fish species Crenicichla lepidota and Moenkhausia bonita as indicators. Two distinct sites were defined to collect data: (1) affected daily by ecotourism (Tourism) and (2) undisturbed (No Tourism). The "stationary point count" method was performed to assess variations in ecological parameters and "ad libitum" and focal animal methods were used to collect behaviour data. The cortisol response of M. bonita to a stress protocol was measured from holding-water. Results showed a significantly increase in species richness, density and diversity at the Tourism site. Nevertheless, behaviour patterns indicated a higher stress at the Tourism site for both species as well higher cortisol levels for M. bonita. In opposition to the ecological measures, the behaviour and physiological ones may be interpreted as an early sign of negative impact caused by ecotourism, prior to changes at community level. Bonito, no estado de Mato Grosso do Sul, é atualmente um importante destino de ecoturismo no Brasil e o seu principal desafio tem sido o de acomodar e ajustar de forma sustentável a crescente procura de turistas sem comprometer a sua integridade ecológica. O objetivo deste estudo consistiu em avaliar o impacto do ecoturismo na ictiofauna do rio Sucuri localizado em Bonito, através da utilização integrada de critérios ecológicos, comportamentais e fisiológicos e utilizando as espécies de peixes Crenicichla lepidota e Moenkhausia bonita como indicadores. Para tal foram determinadas duas áreas distintas de amostragens no rio: (1) local onde ocorrem visitas turísticas diárias (Tourism) e (2) local sem qualquer tipo de impacto humano (No Tourism). O método de censos visuais por pontos fixos foi utilizado para determinar variações nos parâmetros ecológicos e os métodos "ad libitum" e animal focal foram utilizados para coletar dados comportamentais para as duas espécies em estudo. A resposta fisiológica à presença de turistas foi testada em M. bonita através da determinação de cortisol na água por um método não-invasivo de captura, transporte e confinamento. Os resultados obtidos indicam que no local exposto ao turismo há um aumento significativo da riqueza específica, densidade e diversidade de espécies. No entanto, a nível comportamental C. lepidota apresenta mudanças significativas de comportamento alimentar, agonístico, de fuga e guarda do ninho entre os dois locais. Moenkhausia bonita apresenta mudanças significativas não só a nível do seu comportamento alimentar e de fuga, mas também apresenta níveis de cortisol significativamente superiores no local com turismo. Contrariamente aos dados ecológicos, os resultados comportamentais e fisiológicos poderão ser interpretados numa primeira análise como impactos negativos do ecoturismo que surgem em antecipação a mudanças significativas na estrutura e composição das comunidades.


Assuntos
Animais , Ecologia , Hidrocortisona/análise , Viagem , Peixes/classificação
5.
Mol Ecol ; 17(2): 519-32, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18179442

RESUMO

The study of phylogeographical patterns may contribute to a better understanding of factors affecting the dispersal of organisms in ecological and historical times. For intertidal organisms, islands are particularly suitable models allowing the test of predictions related to the efficacy of pelagic larvae dispersal. Here, we study the phylogeographical patterns and gene flow within three groups of species of the genus Patella present in the Macaronesian Islands that have been previously shown to be monophyletic. The genetic variability of around 600 bp of the mitochondrial gene cytochrome c oxidase subunit I was studied by single strand conformation polymorphism and/or sequencing for seven species of limpets. A total of 420 samples were analysed from the Macaronesian archipelagos, North Africa, and Atlantic and Mediterranean shores of the Iberian Peninsula. No clear geographical pattern or temporal congruence was found between the three groups of species, pointing to independent histories and colonization events. However, for the three groups, the split between the Macaronesian and the mainland forms most probably occurred before 3.9 million years ago, predating the establishment of the current circulation patterns. The presence of pelagic larvae in these species is shown to be insufficient to ensure gene flow between continental and Macaronesian populations and between the Macaronesian archipelagos. In the endangered Azorean populations of Patella candei, there is restricted gene flow to Flores and Graciosa.


Assuntos
Evolução Molecular , Gastrópodes/genética , Fluxo Gênico , África Ocidental , Animais , Açores , Complexo IV da Cadeia de Transporte de Elétrons/genética , Gastrópodes/classificação , Gastrópodes/crescimento & desenvolvimento , Geografia , Funções Verossimilhança , Dados de Sequência Molecular , Filogenia , Portugal , Análise de Sequência de DNA , Espanha , Especificidade da Espécie
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