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7881852 
Journal Article 
Food supply mechanisms for cold-water corals along a continental shelf edge 
Thiem, O; Ravagnan, E; Fossa, JanH; Berntsen, J 
2006 
Yes 
Journal of Marine Systems
ISSN: 0924-7963
EISSN: 1879-1573 
60 
3-4 
207-219 
WOS:000238331500002 
In recent years it has been documented that deep-water coral reefs of the species Lophelia pertusa are a major benthic habitat in Norwegian waters. However, basic information about the biology and ecology of this species is still unknown. Lophelia live and thrive under special environmental conditions of which factors such as temperature, water depth, water movement and food supply are important. The present work explores the hypothesis that Lophelia forms reefs in places where the encounter rate of food particles is sufficiently high and stable over long periods of time for continuous growth. This is done by relating the distribution of reefs with the results of numerical ocean modelling. Numerical simulations have been performed with an idealized bottom topography similar to what is found outside parts of the Norwegian coast. In the simulations the model is first forced with an along slope jet and then with an idealized atmospheric low pressure. The model results show that the encounter rates between the particles and the water layer near the seabed are particularly high close to the shelf break. This may indicate that many Lophelia reefs are located along the shelf edges because the supply of food is particularly good in these areas. A sensitivity study of the particle supply in the area close to the seabed for increasing latitude has also been done. This shows that the Ekman transport in the benthic layer tends to create a steady supply of food for benthic organisms near the shelf edge away from the equator. (c) 2005 Elsevier B.V. All rights reserved. 
numerical ocean modelling; coral reef location; shelf edge; geophysical fluid flow