DOM characteristics along the continuum from river to receiving basin: a comparison of freshwater and saline transects     

Brandon M. Stephens  Elizabeth C. Minor 《Aquatic Sciences - Research Across Boundaries》2010,72(4):403-417

The chemical characteristics of bulk (sterile-filtered) and high molecular-weight dissolved organic matter (HMW DOM) were analyzed for freshwater (St. Louis River, Minnesota to Lake Superior) and saline (Elizabeth River, Virginia to Chesapeake Bay) river-to-receiving basin transects. Dissolved organic carbon concentrations and UV–Visible spectroscopy of bulk DOM demonstrated a reduction in organic carbon, colored DOM and aromatic compounds downstream in both transects. The proportion of DOM recoverable via ultrafiltration as HMW material also decreased downstream in both transects, although there was an offset in recoveries between the transects that may be explained by the effects of ionic strength and/or differences in ultrafiltration technique. The analysis of HMW DOM by Fourier transform infrared spectroscopy illustrated similar trends between transects, with a general shift from aromatic/carboxylic compounds nearshore to aliphatic/carbohydrate materials offshore. The parallel changes observed along saline and freshwater transects imply that similar processes play significant roles in the down-gradient alteration of DOM and that ionic strength or pH changes cause second-order effects.  相似文献   

The shape of dark matter haloes: dependence on mass, redshift, radius and formation     

Brandon Allgood  Ricardo A. Flores  Joel R. Primack  rey V. Kravtsov  Risa H. Wechsler †  reas Faltenbacher  James S. Bullock 《Monthly notices of the Royal Astronomical Society》2006,367(4):1781-1796

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Climate governance,justice, and transnational civil society     

Brandon B. Derman 《Climate Policy》2014,14(1):23-41

Justice dilemmas associated with climate change and the regulatory responses to it pose challenges for global governance, arguably hampering progress and raising concerns over efficacy and relevance. Scholarly literature suggests that transnational civil society groups can help address problems of governance and injustice that cross borders and pit states against each other. Findings of a comparative, qualitative study of climate justice advocacy suggest, however, that civil society groups' work in the US and EU is significantly shaped by institutional factors specific to those regimes, limiting advocates' broader impact. Moreover, political opportunities for the pursuit of climate action, and justice particularly, have diminished in those settings. By contrast, the United Nations Framework Convention on Climate Change (UNFCCC) provides greater opportunities for discussions of justice, although civil society actors are significantly constrained within it. It is argued that greater roles for civil society in the UNFCCC could prove constructive in the face of current challenges connected with justice issues. Three themes in civil society advocacy linking principles of global justice with current climate policy debates are summarized. Finally, it is suggested that the first iteration of the UNFCCC Periodic Review provides timely opportunities to more fully draw upon civil society's potential contributions toward a fair and effective global climate regime.

Policy relevance

The roles of civil society organizations in climate governance were examined in three policy contexts: the UNFCCC, the US, and the EU, with special attention to advocacy addressing issues of equity and justice, identified as key challenges for a post-2012 global agreement. Findings suggest that (1) civil society roles are significantly constrained in each context, and (2) political opportunities for climate advocacy have diminished since 2009 in the US and EU, underlining (3) the continued salience of the UNFCCC as a forum for engagement and the construction of effective and equitable climate policy. Potential exists for increased civil society involvement at the UNFCCC to help resolve obstacles based in divergent national priorities. Three areas of justice-focused civil society activity are reviewed for current negotiation topics and the governance structure of the institution. The current UNFCCC Periodic Review is identified as an opportunity to increase civil society involvement.  相似文献