32 research outputs found

    The Perfect Spill: Solutions for Averting the Next Deepwater Horizon

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    In this article the authors comment on the oil spill incident from the Deepwater Horizon, particularly on its economic and ecological damages. The authors highlighted the disaster as an event wherein much is needed to be learned so that future oil spills can be avoided. One lesson refers to the valuability of natural capital assets and other public entities that are at risks due to private interests and that better regulations and incentives are needed to protect these assets against risks

    Salt Marsh Zonal Migration and Ecosystem Service Change in Response to Global Sea Level Rise: A Case Study from an Urban Region

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    Coastal wetland plants are expected to respond to global sea level rise by migrating toward higher elevations. Housing, infrastructure, and other anthropogenic modifications are expected to limit the space available for this potential migration. Here, we explore the ecological and economic effects of projected Intergovernmental Panel on Climate Change (IPCC) 2007 report sea level changes at the plant community scale using the highest horizontal (1 m) and vertical (0.01 m) resolution data available, using a 6 x 6 km area as an example. Our findings show that salt marshes do not always lose land with increasing rates of sea level rise. We found that the lower bound of the IPCC 2007 potential rise (0.18 m by 2095) actually increased the total marsh area. This low rise scenario resulted in a net gain in ecosystem service values on public property, whereas market-based economic losses were predicted for private property. The upper rise scenario (0.59 m by 2095) resulted in both public and private economic losses for this same area. Our work highlights the trade-offs between public and privately held value under the various IPCC 2007 climate change scenarios. We conclude that as wetlands migrate inland into urbanized regions, their survival is likely to be dependent on the rate of return on property and housing investments

    Going With the Flow or Against the Grain? The Promise of Vegetation for Protecting Beaches, Dunes, and Barrier Islands From Erosion

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    Coastlines have traditionally been engineered to maintain structural stability and to protect property from storm‐related damage, but their ability to endure will be challenged over the next century. The use of vegetation to reduce erosion on ocean‐facing mainland and barrier island shorelines – including the sand dunes and beaches on these islands – could be part of a more flexible strategy. Although there is growing enthusiasm for using vegetation for this purpose, empirical data supporting this approach are lacking. Here, we identify the potential roles of vegetation in coastal protection, including the capture of sediment, ecological succession, and the building of islands, dunes, and beaches; the development of wave‐resistant soils by increasing effective grain size and sedimentary cohesion; the ability of aboveground architecture to attenuate waves and impede through‐flow; the capability of roots to bind sediments subjected to wave action; and the alteration of coastline resiliency by plant structures and genetic traits. We conclude that ecological and engineering practices must be combined in order to develop a sustainable, realistic, and integrated coastal protection strategy

    Sea Level Rise and the Dynamics of the Marsh-Upland Boundary

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    During sea level rise, salt marshes transgress inland invading low-lying forests, agricultural fields, and suburban areas. This transgression is a complex process regulated by infrequent storms that flood upland ecosystems increasing soil salinity. As a result upland vegetation is replaced by halophyte marsh plants. Here we present a review of the main processes and feedbacks regulating the transition from upland ecosystems to salt marshes. The goal is to provide a process-based framework that enables the development of quantitative models for the dynamics of the marsh-upland boundary. Particular emphasis is given to the concept of ecological ratchet, combining the press disturbance of sea level rise with the pulse disturbance of storms

    An asymmetry in wave scaling drives outsized quantities of coastal wetland erosion.

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    Wetland shorelines around the world are susceptible to wave erosion. Previous work has suggested that the lateral erosion rate of their cliff-like edges can be predicted as a function of intercepting waves, and yet numerous field studies have shown that other factors, for example, tidal currents or mass wasting of differing soil types, induce a wide range of variability. Our objective was to isolate the unique effects of wave heights, wavelengths, and water depths on lateral erosion rates and then synthesize a mechanistic understanding that can be applied globally. We found a potentially universal relationship, where the lateral erosion rates increase exponentially as waves increase in height but decrease exponentially as waves become longer in length. These findings suggest that wetlands and other sheltered coastlines likely experience outsized quantities of erosion, as compared to oceanic-facing coastlines

    Artificial Modifications of the Coast In Response to the \u3ci\u3eDeepwater Horizon\u3c/i\u3e Oil Spill: Quick Solutions or Long-Term Liabilities?

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    The Deepwater Horizon oil spill threatened many coastal ecosystems in the Gulf of Mexico during the spring and summer of 2010. Mitigation strategies included the construction of barrier sand berms, the restriction or blocking of inlets, and the diversion of freshwater from rivers to the coastal marshes and into the ocean, in order to flush away the oil, on the premise that these measures could reduce the quantity of oil reaching sensitive coastal environments such as wetlands or estuaries. These projects result in changes to the ecosystems that they were intended to protect. Long-term effects include alterations of the hydrological and ecological characteristics of estuaries, changes in sediment transport along the coastal barrier islands, the loss of sand resources, and adverse impacts to benthic and pelagic organisms. Although there are no easy solutions for minimizing the impacts of the Deepwater Horizon disaster on coastal ecosystems, we recommend that federal, state, and local agencies return to the strategic use of long-term restoration plans for this region

    Going with the flow or against the grain? The promise of vegetation for protecting beaches, dunes, and barrier islands from erosion

    Get PDF
    Coastlines have traditionally been engineered to maintain structural stability and to protect property from storm‐related damage, but their ability to endure will be challenged over the next century. The use of vegetation to reduce erosion on ocean‐facing mainland and barrier island shorelines – including the sand dunes and beaches on these islands – could be part of a more flexible strategy. Although there is growing enthusiasm for using vegetation for this purpose, empirical data supporting this approach are lacking. Here, we identify the potential roles of vegetation in coastal protection, including the capture of sediment, ecological succession, and the building of islands, dunes, and beaches; the development of wave‐resistant soils by increasing effective grain size and sedimentary cohesion; the ability of aboveground architecture to attenuate waves and impede through‐flow; the capability of roots to bind sediments subjected to wave action; and the alteration of coastline resiliency by plant structures and genetic traits. We conclude that ecological and engineering practices must be combined in order to develop a sustainable, realistic, and integrated coastal protection strategy

    Divulgação do risco de crédito antes e após a crise financeira de 2008: o caso das empresas do setor bancário do PSI-20

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    Dissertação apresentada para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Contabilidade e FinançasA crise financeira de 2008 evidenciou a necessidade da qualidade da informação divulgada sobre os riscos, assim como a falta de transparência nos relatórios das empresas. Para colmatar este deficit de transparência, as empresas do setor bancário estão sujeitas ao cumprimento das normas emitidas pela Comissão de Mercado e Valores Mobiliários (CMVM), pelo International Accounting Standards Board (IASB), bem como da legislação que resulta dos Acordos de Basileia. O presente estudo procura analisar as práticas de divulgação de informação sobre o risco de crédito antes e “após” a mais recente crise financeira em quatro empresas do setor bancário português cotadas na Euronext Lisboa e incluídas no Portuguese Stock Index (PSI) 20. Para o efeito foi utilizado o método qualitativo e o método da análise de conteúdo. Os dados foram extraídos dos relatórios e contas de 2006 e 2012 das empresas da amostra. Verifica-se que, em geral, as empresas cumpriam os requisitos previstos no normativo contabilístico, regras, regulamentos e outra legislação aplicável.); e que a informação mais divulgada referia-se aos objetivos e políticas de gestão do risco de crédito. Verifica-se, ainda, que a informação divulgada em 2012 melhorou significativamente face a 2006; e houve um grande envolvimento por parte dos órgãos reguladores na adequação das normas e legislações às novas realidades proporcionadas pelo sistema financeiro.Abstract:The financial crisis of 2008 has highlighted the need for the quality of information disclosed about the risks, as well as the lack of transparency in corporate reporting. To overcome this deficit of transparency, companies in the banking sector are subject to compliance with the rules issued by the Comissão de Mercado e Valores Mobiliários (CMVM), by the International Accounting Standards Board (IASB), as well as by the legislation that has derived from the Basel Accords. The present study seeks to analyse the information disclosure practices on credit risk before and "after" the latest financial crisis in four Portuguese banking companies listed on Euronext Lisbon and included in the Portuguese Stock Index (PSI) 20. For this purpose we used the qualitative method and the method of content analysis. The data were extracted from the 2006 and 2012 Annual Accounts of the companies included in the sample. It turns out that, in general, the companies met the requirements set out in accounting standards, rules, regulations, and other applicable law.); and that the information disclosed was referring to the goals and policies of credit risk management. It, also, turns out that the information disclosed in 2012 has significantly improved compared to 2006; and there was a great involvement on the part of regulators on the appropriateness of standards and legislation to the new realities offered by the financial system
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