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41.
Marine legislation world-wide has, as a recent final objective, the maintenance of a good environmental or ecological status for marine waters, habitats and resources. The concept of environmental status takes into account the structure, function and processes of marine ecosystems, bringing together physical, chemical, physiographic, geographic and climatic factors: subsequently, integrating such conditions, with anthropogenic impacts and activities undertaken in the area concerned. Such an approach is intended to permit an assessment of the environmental status at the ecosystem level, i.e. ‘ecosystem-based approach’, or ‘ecosystem-based management’.Such legislation emphasises the need for the development of methodologies, to assess environmental status. As such the knowledge acquired within Regional Seas, discussed at International Symposia and, finally, published as Special Issues, can serve as the basis for a regional ecosystem-based approach to management and the integrative assessment of marine systems. Hence, the Bay of Biscay is used in this contribution, as an example, to show past and present research, together with perspectives for the future. It is concluded that collaboration between institutions (marine research institutes, universities) and countries (France, Spain, Portugal, the United Kingdom and Ireland) could result in an interesting ‘case-study’, for the further implementation of the European Marine Strategy Framework Directive, at the level of this particular Regional Sea. In this way, the experience gained in the implementation of the Water Framework Directive within the ecoregion, together with the information collated in the eleven International Symposia of Oceanography of the Bay of Biscay, celebrated until now, can be very useful, for an ecosystem-based management approach for this Regional Sea. 相似文献
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Jonathon Collins 《The Australian geographer》2014,45(3):289-307
ABSTRACTBangladesh is at the forefront of countries experiencing and debating climate change, despite having contributed little to global emissions, and has the greatest vulnerability to climate change due to inadequate institutional support for the dense population dispersed in low-lying terrain. A micro-level study of livelihoods in the Panpatti Union, a district of the coastal zone exposed to climate stress and an array of other social, economic and political stresses, demonstrated that adaptation strategies to a range of shocks were both reactive and proactive. The persistent nature of shocks, and the limited margins in which to respond, meant that achieving sustainable long-term livelihoods was unusually difficult. Despite cases of dynamism and flexibility, where livelihoods had been effectively diversified, rural people largely failed to reduce their exposure to vulnerability. That was especially true of extremely poor, landless and female-headed households. In such challenging circumstances external interventions were required to ensure sustainable development, but were unlikely because of the isolation of Panpatti and the number of villages and people in similar circumstances. This emphasised the need to develop a more robust livelihoods framework to support the most vulnerable communities in severe economic and environmental contexts where climate change is likely to exacerbate all existing problems. 相似文献
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Manuela Magliocchetti Steve J. Maddox Ed Hawkins John A. Peacock Joss Bland-Hawthorn Terry Bridges Russell Cannon Shaun Cole Matthew Colless Chris Collins Warrick Couch Gavin Dalton Roberto de Propris Simon P. Driver George Efstathiou Richard S. Ellis Carlos S. Frenk Karl Glazebrook Carole A. Jackson Bryn Jones Ofer Lahav Ian Lewis Stuart Lumsden Peder Norberg Bruce A. Peterson Will Sutherland Keith Taylor 《Monthly notices of the Royal Astronomical Society》2004,350(4):1485-1494
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The 2dF Galaxy Redshift Survey: the bJ -band galaxy luminosity function and survey selection function
Peder Norberg Shaun Cole Carlton M. Baugh Carlos S. Frenk Ivan Baldry Joss Bland-Hawthorn Terry Bridges Russell Cannon Matthew Colless Chris Collins Warrick Couch Nicholas J. G. Cross Gavin Dalton Roberto De Propris Simon P. Driver George Efstathiou Richard S. Ellis Karl Glazebrook Carole Jackson Ofer Lahav Ian Lewis Stuart Lumsden Steve Maddox Darren Madgwick John A. Peacock Bruce A. Peterson Will Sutherland Keith Taylor 《Monthly notices of the Royal Astronomical Society》2002,336(3):907-931
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Peder Norberg Carlton M. Baugh Ed Hawkins Steve Maddox John A. Peacock Shaun Cole Carlos S. Frenk Joss Bland-Hawthorn Terry Bridges Russell Cannon Matthew Colless Chris Collins Warrick Couch Gavin Dalton Roberto De Propris Simon P. Driver George Efstathiou Richard S. Ellis Karl Glazebrook Carole Jackson Ofer Lahav Ian Lewis Stuart Lumsden Darren Madgwick Bruce A. Peterson Will Sutherland Keith Taylor 《Monthly notices of the Royal Astronomical Society》2001,328(1):64-70
We investigate the dependence of the strength of galaxy clustering on intrinsic luminosity using the Anglo-Australian two degree field galaxy redshift survey (2dFGRS). The 2dFGRS is over an order of magnitude larger than previous redshift surveys used to address this issue. We measure the projected two-point correlation function of galaxies in a series of volume-limited samples. The projected correlation function is free from any distortion of the clustering pattern induced by peculiar motions and is well described by a power law in pair separation over the range . The clustering of galaxies in real space is well-fitted by a correlation length and power-law slope . The clustering amplitude increases slowly with absolute magnitude for galaxies fainter than M *, but rises more strongly at higher luminosities. At low luminosities, our results agree with measurements from the Southern Sky Redshift Survey 2 by Benoist et al. However, we find a weaker dependence of clustering strength on luminosity at the highest luminosities. The correlation function amplitude increases by a factor of 4.0 between and −22.5, and the most luminous galaxies are 3.0 times more strongly clustered than L * galaxies. The power-law slope of the correlation function shows remarkably little variation for samples spanning a factor of 20 in luminosity. Our measurements are in very good agreement with the predictions of the hierarchical galaxy formation models of Benson et al. 相似文献
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Ian Lewis Michael Balogh Roberto De Propris Warrick Couch Richard Bower Alison Offer Joss Bland-Hawthorn Ivan K. Baldry Carlton Baugh Terry Bridges Russell Cannon Shaun Cole Matthew Colless Chris Collins Nicholas Cross Gavin Dalton Simon P. Driver George Efstathiou Richard S. Ellis Carlos S. Frenk Karl Glazebrook Edward Hawkins Carole Jackson Ofer Lahav Stuart Lumsden Steve Maddox Darren Madgwick Peder Norberg John A. Peacock Will Percival Bruce A. Peterson Will Sutherland Keith Taylor 《Monthly notices of the Royal Astronomical Society》2002,334(3):673-683
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V. R. Eke Carlos S. Frenk Carlton M. Baugh Shaun Cole Peder Norberg John A. Peacock Ivan K. Baldry Joss Bland-Hawthorn Terry Bridges Russell Cannon Matthew Colless Chris Collins Warrick Couch Gavin Dalton Roberto de Propris Simon P. Driver George Efstathiou Richard S. Ellis Karl Glazebrook Carole A. Jackson Ofer Lahav Ian Lewis Stuart Lumsden Steve J. Maddox Darren Madgwick Bruce A. Peterson Will Sutherland Keith Taylor 《Monthly notices of the Royal Astronomical Society》2004,355(3):769-784