2332-2632-CoastalZone-2016_Posters-Accepted-Abstracts

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Page 105
Coastal Zones 2016
May 16-18, 2016
Volume 4, Issue 1(Suppl) Oceanography 2016
ISSN:2332-2632, OCN an open access journal
conferenceseries .com
May 16-18, 2016 Osaka, Japan
Coastal Zones International Conference on
Oceanography 2016, 4:1(Suppl)
From Coast to Coast – Keeping the Ocean Integrity through Articulated Governance Regimes
Yves Henocque
IFREMER (JAMSTEC; OPRI), France
Ocean is one but governance regimes are legions and uncoordinated. Any coastal zone management initiative needs to be
put into context at the next larger scale and so on as a contribution to the regional seas and global ocean integrity. The
other way around, any global vision needs to be rooted into regional, national and local implementation. More than 20 years
ago, the first Rio conference on environment and development (1992), then comforted in Johannesburg (2002) and again in
Rio (2012), gave us the framework and principles of action towards the construction of new forms of governance including
catchment and coastal areas integrated management,together with the ecosystem approach principles of the Convention of
Biological Diversity and, a bit later, the Reykjavik Declaration on Responsible Fisheries (2001). Since then, many initiatives,
policies or programmes have been launched and carried out all around the world but it seems like these new forms of governance
are better achieved at small scale and the closer one gets to shore. There are still few practical examples in offshore systems
and even fewer in wider systems that couple nearshore and pelagic areas. These experiences will be reviewed and lessons
drawn regarding best practices in scaling up management to scales appropriate to vast, interconnected systems through actual
holistic, cross-sectoral, and truly integrated management.
Causes, Consequences and Mitigation of Hypoxia in Coastal Habitats
Gilbert T Rowe
TAMUG,USA
The generally accepted causes of hypoxia (oxygen concentrations < 2 mg/Liter) in the coastal zone are 1. eutrophication
resulting from nutrient loading, 2. water column stratification created by a freshwater plume and 3. excess terrestrial
organic matter, but the relative importance among these varies between ecosystems and likewise has been the subject of intense
debate. The consequences of hypoxia are 1. preservation of organic matter in the sediments, 2. elimination of both sessile and
motile megafauna, and 3. a decrease in mean animal size and diversity among sediment dwelling invertebrates. Enhanced
production of trace gases from anaerobic metabolism and diminished fisheries production may also be significant but remain
open to question. Blooms of sediment-dwelling sulfide-oxidizing bacteria may prevent toxic sulfide from diffusing into the
water column. Mitigation strategies include reducing nutrient loading, reducing freshwater flow and altering freshwater flow
into wetlands, but there is wide-spread disagreement on which of these is most effective or even tractable. Climate change and
human impacts in the coastal zone may increase the frequency and extent of hypoxia by increasing nutrient loading. Sea level
rise may exacerbate loss of wetlands. Diminished supplies of freshwater to estuaries may increase salinities in estuaries and
shrink the length of the fresh to salt water gradient in estuaries and near-shore, while flooding and sea level rise may extend
the fresh-to-salt zonation pattern and increase stratification, thus enlarging areas of hypoxia. Increases in temperature will
enhance vertical stratification and metabolic rates, both of which would add to the geographic areal extent of hypoxia and
biological stresses. 'Ecosystem services' must be considered when remedial actions are to be considered, but these will differ
depending of the ecosystem in question.