The Benguela ecosystem: part V. The coastal zone
Branch, G.M.; Griffiths, C.L. (1988). The Benguela ecosystem: part V. The coastal zone, in: Barnes, H. et al. Oceanogr. Mar. Biol. Ann. Rev. 26. Oceanography and Marine Biology: An Annual Review, 26: pp. 395-486
In: Barnes, H. et al. (1988). Oceanogr. Mar. Biol. Ann. Rev. 26. Oceanography and Marine Biology: An Annual Review, 26. Aberdeen University Press: Aberdeen. ISBN 0-08-036397-0; e-ISBN 0-203-02079-0. 615 pp., more
In: Oceanography and Marine Biology: An Annual Review. Aberdeen University Press/Allen & Unwin: London. ISSN 0078-3218; e-ISSN 2154-9125, more
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| Authors | | Top |
- Branch, G.M.
- Griffiths, C.L.
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| Abstract |
This review covers rocky shores, sandy beaches and kelp beds of the Benguela region, on the west coast of southern Africa. Early work concerned taxonomy, biogeography, zonation, and physiological tolerances, but has given way to studies of energy flow, physiological adaptations, and biological interactions. On rocky shores, important features include the effect of wave action on community structure, the impact of seabirds (as predators and guano producers); the role of limpets in controIling algal growth and their domination of certain zones; and the effects of various predators, particularly on mussels. New concepts have emerged with respect to competition, metabolic adaptations and bacteriolysis by mussels. Kelp wrack dominates some sandy beaches, underpinning a food-web of meiofauna and air-breathing insects and crustaceans. On such beaches diversity and biomass are greatest high on the shore, reversing normal zonation patterns. Beaches lacking wrack support suspension-feeding bivalves (Donax serra) and scavenging whelks (Bullia spp.). Flows of energy, nitrogen, and carbon through kelp beds have been quantified, leading to the novel concept of a 'faeces loop' as a means of recycling materials. UpweIling and downwelling dominate the availability of food to filter-feeders. Rock lobsters fulfil a critical role as predators, controlling benthic community structure. Under certain circumstances, however, they can be excluded by whelks, apparently leading to an alternative stable state. |
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