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1.
PLoS One ; 15(12): e0242485, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33382709

RESUMO

The high rates of bat mortality caused by operating wind turbines is a concern for wind energy and wildlife stakeholders. One theory that explains the mortality is that bats are not only killed by impact trauma, but also by barotrauma that results from exposure to the pressure variations caused by rotating turbine blades. To date, no published research has calculated the pressure changes that bats may be exposed to when flying near wind turbines and then used these data to estimate the likelihood that turbines cause barotrauma in bats. To address this shortcoming, we performed computational fluid dynamics simulations of a wind turbine and analytical calculations of blade-tip vortices to estimate the characteristics of the sudden pressure changes bats may experience when flying near a utility-scale wind turbine. Because there are no data available that characterize the pressure changes that cause barotrauma in bats, we compared our results to changes in pressure levels that cause barotrauma and mortality in other mammals of similar size. This comparison shows that the magnitude of the low-pressures bats experience when flying near wind turbines is approximately 8 times smaller than the pressure that causes mortality in rats, the smallest mammal for which data are available. The magnitude of the high-pressures that bats may experience are approximately 80 times smaller than the exposure level that causes 50% mortality in mice, which have a body mass similar to several bat species that are killed by wind turbines. Further, our results show that for a bat to experience the largest possible magnitude of low- and high-pressures, they must take very specific and improbable flight paths that skim the surface of the blades. Even a small change in the flight path results in the bat being hit by the blade or experiencing a much smaller pressure change. Accordingly, if bats have a physiological response to rapid low- and high-pressure exposure that is similar to other mammals, we conclude that it is unlikely that barotrauma is responsible for a significant number of turbine-related bat fatalities, and that impact trauma is the likely cause of the majority of wind-turbine-related bat fatalities.


Assuntos
Quirópteros , Modelos Estatísticos , Centrais Elétricas/ética , Ferimentos não Penetrantes/diagnóstico , Animais , Barotrauma , Camundongos , Ratos , Vento
2.
Sci Eng Ethics ; 24(6): 1801-1807, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29067625

RESUMO

Despite the size and thanks to the rich brown coal reserves, the Czech Republic is one of the leading energy producers in Europe, and the 7th biggest exporter of electricity in the world. However, following the climate change mitigation, the novel energy policy that enhances the reduction of coal mining is about to be implemented. A preliminary material flow analysis of the Czech energy sector was carried out. The data obtained confirmed that this government act would result in a dramatic reduction of revenues from electricity sales. Conversely, increased costs would be necessary in order to modernize nuclear power plants and promote the production of renewable energy. In addition, the economic analysis revealed that the act might be prejudicial to economic relations in Central and Western-European countries as some of them are significantly dependent on the electricity imported from the Czech Republic. Disputes between engineers and politicians were highlighted. The aforementioned interrelations were subsequently analyzed and a conclusion was made stating that global interests should have the highest moral priority.


Assuntos
Carvão Mineral , Conservação de Recursos Energéticos , Eletricidade , Engenharia , Centrais Elétricas , Política Pública , Mudança Climática , Conservação de Recursos Energéticos/economia , Custos e Análise de Custo , República Tcheca , Engenharia/economia , Engenharia/ética , Europa (Continente) , Governo , Humanos , Renda , Princípios Morais , Centrais Nucleares/economia , Centrais Nucleares/ética , Política , Centrais Elétricas/economia , Centrais Elétricas/ética , Política Pública/economia
3.
PLoS One ; 12(10): e0185527, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29040272

RESUMO

Tropical forest fragmentation creates insular biological communities that undergo species loss and changes in community composition over time, due to area- and edge-effects. Woody lianas thrive in degraded and secondary forests, due to their competitive advantage over trees in these habitats. Lianas compete both directly and indirectly with trees, increasing tree mortality and turnover. Despite our growing understanding of liana-tree dynamics, we lack detailed knowledge of the assemblage-level responses of lianas themselves to fragmentation, particularly in evergreen tropical forests. We examine the responses of both sapling and mature liana communities to landscape-scale forest insularization induced by a mega hydroelectric dam in the Brazilian Amazon. Detailed field inventories were conducted on islands created during reservoir filling, and in nearby mainland continuous forest. We assess the relative importance of variables associated with habitat fragmentation such as area, isolation, surrounding forest cover, fire and wind disturbance, on liana community attributes including abundance, basal area, diversity, and composition. We also explore patterns of liana dominance relative to tree saplings and adults ≥10 cm diameter at breast height. We find that 1) liana community composition remains remarkably similar across mainland continuous forest and islands, regardless of extreme area- and edge- effects and the loss of vertebrate dispersers in the latter; and 2) lianas are increasing in dominance relative to trees in the sapling layer in the most degraded islands, with both the amount of forest cover surrounding islands and fire disturbance history predicting liana dominance. Our data suggest that liana communities persist intact in isolated forests, regardless of extreme area- and edge-effects; while in contrast, tree communities simultaneously show evidence of increased turnover and supressed recruitment. These processes may lead to lianas becoming a dominant component of this dam-induced fragmented landscape in the future, due to their competitive advantage over trees in degraded forest habitats. Additional loss of tree biomass and diversity brought about through competition with lianas, and the concurrent loss of carbon storage, should be accounted for in impact assessments of future dam development.


Assuntos
Conservação dos Recursos Naturais , Plantas Daninhas/fisiologia , Centrais Elétricas/ética , Árvores/fisiologia , Biomassa , Brasil , Ecossistema , Florestas , Humanos , Rios , Especificidade da Espécie , Clima Tropical
4.
Sci Eng Ethics ; 21(2): 359-79, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24744115

RESUMO

Community acceptance still remains a challenge for wind energy projects. The most popular explanation for local opposition, the Not in My Backyard effect, has received fierce criticism in the past decade. Critics argue that opposition is not merely a matter of selfishness or ignorance, but that moral, ecological and aesthetic values play an important role. In order to better take such values into account, a more bottom-up, participatory decision process is usually proposed. Research on this topic focusses on either stakeholder motivations/attitudes, or their behavior during project implementation. This paper proposes a third research focus, namely the 'objects' which elicit certain behavioral responses and attitudes-the wind turbine and parks. More concretely, this paper explores Value Sensitive Design (VSD) as way to arrive at wind turbines and parks that better embed or reflect key values. After a critical discussion of the notion of acceptance versus acceptability and support, the paper discusses existing literature on ecology and aesthetics in relation to wind turbine/park design, which could serve as 'building blocks' of a more integral VSD approach of the topic. It also discusses the challenge of demarcating wind park projects as VSD projects. A further challenge is that VSD has been applied mainly at the level of technical artifacts, whereas wind parks can best be conceptualized as socio-technical system. This new application would therefore expand the current practice of VSD, and may as a consequence also lead to interesting new insights for the VSD community. The paper concludes that such an outcome-oriented approach of wind turbines and park is worth exploring further, as a supplement to rather than a replacement of the process-oriented approach that is promoted by the current literature on community acceptance of wind parks.


Assuntos
Atitude , Comportamento do Consumidor , Meio Ambiente , Centrais Elétricas/ética , Características de Residência , Valores Sociais , Vento , Ecologia , Fontes Geradoras de Energia , Estética , Humanos , Princípios Morais , Motivação , Comportamento Social
6.
Risk Anal ; 24(1): 147-56, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15028007

RESUMO

A common problem in ethics is that people often desire an end but fail to take the means necessary to achieve it. Employers and employees may desire the safety end mandated by performance standards for pollution control, but they may fail to employ the means, specification standards, necessary to achieve this end. This article argues that current (de jure) performance standards, for lowering employee exposures to ionizing radiation, fail to promote de facto worker welfare, in part because employers and employees do not follow the necessary means (practices known as specification standards) to achieve the end (performance standards) of workplace safety. To support this conclusion, the article argues that (1) safety requires attention to specification, as well as performance, standards; (2) coal-mine specification standards may fail to promote performance standards; (3) nuclear workplace standards may do the same; (4) choosing appropriate means to the end of safety requires attention to the ways uncertainties and variations in exposure may mask violations of standards; and (5) correcting regulatory inattention to differences between de jure and de facto is necessary for achievement of ethical goals for safety.


Assuntos
Minas de Carvão/ética , Saúde Ocupacional , Centrais Elétricas/ética , Poluentes Radioativos do Ar/análise , Minas de Carvão/legislação & jurisprudência , Monitoramento Ambiental , Humanos , Exposição Ocupacional/prevenção & controle , Saúde Ocupacional/legislação & jurisprudência , Centrais Elétricas/legislação & jurisprudência , Gestão de Riscos , Estados Unidos , United States Occupational Safety and Health Administration
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