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Resonant cavity measurements of the effects of ‘red water,’ plankton on the attenuation of underwater sound
Oceanographic Abstracts
103
Coastal Engineering, Congr~s 1961 de I'A.I.R.H., article paru dans !e bulletin du C.O.E.C. de juin 1961). Principe et exemples du calcul sur machine /t calculer 61ectronique. Methods for calculating tidal level differences and currents in coastal sea areas and oceans have been discussed in papers submitted to the Seventh Congress on Coastal Engineering, the 1961 I.A.H.R. Congress, and in an article published in the June 1961 issue of the C.O.E.C. Bulletin. Electronic machine calculation principles, and calculated examples. GRICE G. D., 1961. Calanoid eopepods from equatorial waters of the Pacific Ocean. Fish. Bull.,
U.S. Fish. and Wildlife Service (Fish. Bull. 186), 61: 172-246. A systematic study was made of the calanoid copepods found in 14 zooplankton samples, four of which were obtained from within the recently discovered equatorial undercurrent (Cromwell current), collected between 5°N and 5°S and 130OE and 120W. One hundred and ten species belonging to 18 families were recorded. Descriptive notes, measurements and figures were given for most species with citations to previous occurrences in the Pacific Ocean. Except for Scolecithricella tenuiserrata (Giesbrecht), the copepod species in samples collected from within the equatorial undercurrent were not very different from those in samples obtained adjacent to the current. The numerical abundance and species diversity in equatorial waters were briefly compared with that reported for the northwestern Pacific Ocean. Acrocalanus andersoni Bowman, Chirundina indica Sewell and Haloptilus fertilis (Giesbrecht) were reported for the first time from the Pacific Ocean. Three species, Xanthocalanus dilatus, Amallophora smithae and Scolecithricella tropica, are described as new, and hitherto unknown males of Gaetanus miles Giesbrecht and G. minor Farran are briefly illustrated from juvenile specimens. It was proposed that Euchirella brevis Sars is a synonym for E. amoena Giesbrecht; Euchaeta consimilis Farran for E. concinna Dana; Scoecithrix hmgicornis Scott, and Scolecithricella spinipedata Mori for Scolecithricella ctenopus (Giesbrecht); and Centropages pacificus Chiba for C. elongatus Giesbrecht. GUNNERSON C. G. and K. O. EMERY, 1962. Suspended sediment and plankton over San Pedro Basin, California. Limnol. and Oceanogr., 7 (1): 14-20. The distribution of suspended sediment and plankton throughout the upper 275 m of water over San Pedro Basin, California, was observed on 4 cruises in 1957-58. In general, plankton concentrations varied inversely with depth while suspended sediment concentrations varied inversely with distance from shore. On 3 of the cruises, localized high concentrations of 2 ~. diameter sediment were found near the bottom at depths between 200 and 275 m. Evidence of entrainment and subsequent sinking of plankton along with the suspended sediment suggests turbidity currents originating within the upper 50 m on the continental shelf.
HANSEN,K., 1962. The structure of the salt-marsh area at Ballum, SW Jutland. Medd. SkallingLab., 17: 75-86. Reprint from: Medd. Dansk Geol. Forening, Kobenhavn, 15: 75-86. Borings through the Ballum salt marsh area indicate, that in late glacial time, and in the beginning of the postglacial time the river Bredeaa ran in a much wider and deeper valley than today. In the shallow basins on both sides of the river bed homogeneous clay was deposited. When the transgressing North Sea entered the river by extraordinary high tides, sand was deposited in the outer part of the river bed and a sapropelitic gyttja farther upstream. As the postglacial transgression continued the outermost part of the river bed silted up and low ridges (klints) of stratified clay were built upon the marsh surface, in the same way as it does in the wadden today, HANSEN P. G. and E. G. BARHAM,1962. Resonant cavity measurements of the effects of ' red water,' plankton on the attenuation of underwater sound. Limnol. and Oceanogr., 7 (1): 8-13. During the summer of 1958, a ' red water' bloom caused by the dinoflagellate, Gonyaulax poh,edra, occurred off San Diego, California. Using resonant cavity instrumentation, high attenuations were measured at sea (64 db/kyd max), and these measurements were repeated in the laboratory with collected samples. The mechanism of sound absorption has not been demonstrated, but it might be related to gaseous metabolic by-products of the planktonic organisms. HART T. J., 1962. Notes on the relation between transparency and plankton content of the surface waters of the Southern Ocean. Deep-Sea Res., 9 (2): 109-114, Secchi disc readings and corresponding phytoplankton values obtained during the 1938-9 season, in the surface waters of two areas of the southern ocean remote from land, are recorded. They show an inverse correlation strong enough to suggest that phytoplankton quantity is the main factor changing the penetration of light into those waters with change of season. It is concluded that in open sea areas where precision data on light penetration are not available, some knowledge of the seasonal cycle of the microplankton should give a good rough indication of the variations in transparency to be expected.
103
Coastal Engineering, Congr~s 1961 de I'A.I.R.H., article paru dans !e bulletin du C.O.E.C. de juin 1961). Principe et exemples du calcul sur machine /t calculer 61ectronique. Methods for calculating tidal level differences and currents in coastal sea areas and oceans have been discussed in papers submitted to the Seventh Congress on Coastal Engineering, the 1961 I.A.H.R. Congress, and in an article published in the June 1961 issue of the C.O.E.C. Bulletin. Electronic machine calculation principles, and calculated examples. GRICE G. D., 1961. Calanoid eopepods from equatorial waters of the Pacific Ocean. Fish. Bull.,
U.S. Fish. and Wildlife Service (Fish. Bull. 186), 61: 172-246. A systematic study was made of the calanoid copepods found in 14 zooplankton samples, four of which were obtained from within the recently discovered equatorial undercurrent (Cromwell current), collected between 5°N and 5°S and 130OE and 120W. One hundred and ten species belonging to 18 families were recorded. Descriptive notes, measurements and figures were given for most species with citations to previous occurrences in the Pacific Ocean. Except for Scolecithricella tenuiserrata (Giesbrecht), the copepod species in samples collected from within the equatorial undercurrent were not very different from those in samples obtained adjacent to the current. The numerical abundance and species diversity in equatorial waters were briefly compared with that reported for the northwestern Pacific Ocean. Acrocalanus andersoni Bowman, Chirundina indica Sewell and Haloptilus fertilis (Giesbrecht) were reported for the first time from the Pacific Ocean. Three species, Xanthocalanus dilatus, Amallophora smithae and Scolecithricella tropica, are described as new, and hitherto unknown males of Gaetanus miles Giesbrecht and G. minor Farran are briefly illustrated from juvenile specimens. It was proposed that Euchirella brevis Sars is a synonym for E. amoena Giesbrecht; Euchaeta consimilis Farran for E. concinna Dana; Scoecithrix hmgicornis Scott, and Scolecithricella spinipedata Mori for Scolecithricella ctenopus (Giesbrecht); and Centropages pacificus Chiba for C. elongatus Giesbrecht. GUNNERSON C. G. and K. O. EMERY, 1962. Suspended sediment and plankton over San Pedro Basin, California. Limnol. and Oceanogr., 7 (1): 14-20. The distribution of suspended sediment and plankton throughout the upper 275 m of water over San Pedro Basin, California, was observed on 4 cruises in 1957-58. In general, plankton concentrations varied inversely with depth while suspended sediment concentrations varied inversely with distance from shore. On 3 of the cruises, localized high concentrations of 2 ~. diameter sediment were found near the bottom at depths between 200 and 275 m. Evidence of entrainment and subsequent sinking of plankton along with the suspended sediment suggests turbidity currents originating within the upper 50 m on the continental shelf.
HANSEN,K., 1962. The structure of the salt-marsh area at Ballum, SW Jutland. Medd. SkallingLab., 17: 75-86. Reprint from: Medd. Dansk Geol. Forening, Kobenhavn, 15: 75-86. Borings through the Ballum salt marsh area indicate, that in late glacial time, and in the beginning of the postglacial time the river Bredeaa ran in a much wider and deeper valley than today. In the shallow basins on both sides of the river bed homogeneous clay was deposited. When the transgressing North Sea entered the river by extraordinary high tides, sand was deposited in the outer part of the river bed and a sapropelitic gyttja farther upstream. As the postglacial transgression continued the outermost part of the river bed silted up and low ridges (klints) of stratified clay were built upon the marsh surface, in the same way as it does in the wadden today, HANSEN P. G. and E. G. BARHAM,1962. Resonant cavity measurements of the effects of ' red water,' plankton on the attenuation of underwater sound. Limnol. and Oceanogr., 7 (1): 8-13. During the summer of 1958, a ' red water' bloom caused by the dinoflagellate, Gonyaulax poh,edra, occurred off San Diego, California. Using resonant cavity instrumentation, high attenuations were measured at sea (64 db/kyd max), and these measurements were repeated in the laboratory with collected samples. The mechanism of sound absorption has not been demonstrated, but it might be related to gaseous metabolic by-products of the planktonic organisms. HART T. J., 1962. Notes on the relation between transparency and plankton content of the surface waters of the Southern Ocean. Deep-Sea Res., 9 (2): 109-114, Secchi disc readings and corresponding phytoplankton values obtained during the 1938-9 season, in the surface waters of two areas of the southern ocean remote from land, are recorded. They show an inverse correlation strong enough to suggest that phytoplankton quantity is the main factor changing the penetration of light into those waters with change of season. It is concluded that in open sea areas where precision data on light penetration are not available, some knowledge of the seasonal cycle of the microplankton should give a good rough indication of the variations in transparency to be expected.