Continental Shelves: (Ecosystems of the World)

Although continental shelves take up only a small part of the ocean's surface, they have their own economic importance. This book describes the biological characteristics of continental shelves between land masses on one side and the open ocean on the other. The influence of the land often causes increased fertility of inner shelf water, including a higher production, but can also increase environmental stress which on marine organisms. Tidal currents cause rapid water mixing and promote exchange of sediments and organic materials between the sea floor with its benthic communities and the overlying water. Offshore, intrusions of ocean eddies and upwelling introduce oceanic species. The book provides a review of general principles of shelf ecosystems, and describes their relation with physical, chemical and geological conditions. It also provides a description of a number of specific shelves from polar to tropical regions. Continental Shelves will be of interest to marine biologists, marine chemists, microbiologists, those working in fisheries science and in ecological modelling. It is hoped that it will give an impetus to accelerated research of continental shelves.

Table of Contents:
1. Introduction (H. Postma, J.J. Zijlstra). 2. Physical and Chemical Oceanographic Aspects of Continental Shelves (H. Postma). Periodic water movements. Residual currents. Stratifications. Upwelling and downwelling. Fronts. The fate of chemical elements. Summary. 3. An Introduction to the Geology of Continental Shelves (D. Eisma). Extent and origin of continental shelves. Sea-level changes. Bottom sediment patterns. Sediment transport on the shelf. Geotechnical properties of shelf sediments. Summary. 4. Plankton Characteristics (V. Smetacek). Basic processes of pelagic ecosystems. Distinguishing features of continental shelves. Organisms of the shelf plankton. Regional and temporal considerations. Acknowledgements. 5. Characteristics of the Benthic Fauna (D.S. McLusky, A.D. McIntyre). Structure of the benthic communities. Methods of study. Dynamics of the ecosystem. Variations with latitude. Economic aspects. 6. Fish Populations and Fisheries: Their Perturbations, Natural and Man-induced (G.D. Sharp). Setting the scene. Neritic habitats. Neritic fish populations. Environments, life-history patterns and observed variations. Scales of productivity and dispersion in the marine ecosystem. Geographic variations of the neritic zone. Dominant ambient influences on the neritic regime. The habitat matrix. Ecosystem perturbations and long-term processes. Conclusions. 7. The Flow of Energy in Marine Ecosystems, with special reference to the Continental Shelf (D.H. Cushing). Methods. The forms of production. The quantities produced. The regions of production. The transfer of energy. Conclusions. 8. The North Sea Ecosystem (J.J. Zijlstra). Topography. Hydrography. Nutrients. Phytoplankton. Zooplankton. Benthos. Fish and fisheries. Conclusions. 9. The Continental Shelf Ecosystem off the Northeast Coast of the United States (K. Sherman et al.). Bathymetry. Hydrography. Primary productivity. Nutrients. Zooplankton. Benthos. Fish fauna of the New England shelf region. Fish biomass and yield. Production in different trophic levels of Northwest Atlantic shelf ecosystems. Possible explanations for production differences. Appendix. 10. The Barents Sea (O. Dragesund, J. Gjosaeter). Boundaries and bottom topography. Hydrography. Nutrient salts. Phytoplankton. Zooplankton. Benthos. Fish. Interrelations of the ecosystem of the Barents Sea. 11. The Gulf of Thailand (D. Menasveta, V. Hongskul). General characteristics. Living resources. Fisheries. Resource management. Summary and conclusions. Author Index. Systematic Index. General Index.