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Polychaete fauna of South Africa: Part 7. Species from depths between 1000 and 3330 metres west of Cape Town
Oceanographic Abstracts
37
DARBYSHIRE,]V[., 1963. Wave measurements made by the National Institute of Oceanography. In: Ocean Wave Spectra, Proc. Conf., Easton, Md., May 1-4, 1961, Prentice-Hall, N.J. 285-291. The National Institute of Oceanography has been making instrumental measurements of sea waves since 1945. An account is given here of wave measurements made in the North Atlantic Ocean and around the coasts of Britain since that time, indicating what records are available and summarising the information that has been extracted from these records. DAVIS, C. C., 1963. On questions of production and productivity in ecology. Arch. Hydrobiol., 59 (2): 145-161. Confusion of terminology and of thought makes it necessary to examine production-productivity theory in some detail. A fundamental dichotomy in concepts lies between the potential rate of formation of organisms in a given area or volume of water under ideal conditions and the actual rate of formation under actually existing conditions. The former is called productivity and the latter production. A second dichotomy applies equally to each of the above : the dichotomy between the circulation of matter and the flow of energy through an ecosystem. There are, then, four fundamental concepts, energoproductivity, energoprodoction, organoproductivity and organoproduction. Each of these in turn is subdivisible into net and gross production (or productivity), and primary, s~ondary, total, etc., categories. In addition, the concepts of yield, standing stock, biomass and organomass are discussed. An appropriate detailed systematic terminology is suggested to be applied to the specific concepts. This is compared with the varying terminologies used by other authors. DAY, J. H., 1963. Polychuete fauna of South Africa: Part 7. Species from depths between 1000 and 3330 metres west of Cape Town. Ann. S. Africa. Mus., 46 (14): 353-371. Twenty-eight species of Polychaeta are described from abyssal dredgings west of Cape Town. The collection includes four new species and eleven new records for this area. Only four of these species are known from depths less than 100 m; the rest are widespread at abyssal depths. There is no obvious Antarctic component. DE ANGELIS, C. M., 1962. Distribuzione ed ¢cologia di alcune specie di Dinoflagellati di acque salmastre. Pubbl. Staz. Zool., Napoli, 32 (Suppl.): 301-314. Some species of dinoflagcllates more generally found in Italian coastal ponds, and their distribution and adaptability to the surroundings are examined. The importance of salinity, temperature and eutrophic habitat are also pointed out. The author considers some morphological variations found specially in Prorocentrum species. Such individual variations never produce a population selected in races, but make the high degree of variability peculiar to the species evident. DE LEONmUS, P. S., 1963. Power spectra of surface wave heights estimated from recordings made from a submerged hovering submarine. In: Ocean Wave Spectra, Prec. Conf., Easton, Md., May 1-4, 1961, Prentice-Hall, N.J., 243-249. The technique of obtaining surface wave records with an inverted echo sounder from a submerged hovering submarine, and some of the errors associated with such a wave measuring system, are discussed. Examples of digital power spectral estimates obtained from recordings arc presented, Significant wave heights obtained by these wave spectra are compared to hindcast values using the Pierson-Neuruann spectra. The agreement is fair. DELLA CROCE,N., 1962. Zonazione zooplanctonica nel Golfo di Napoli. Problemi ecologici delle zone litorale del Mediterranco 17-23 lugiio 1961. Pubbl. Staz. Zool. Napoli, Vol. 32 Suppl.: 368-379. Some features of the superficial waters of the Gulf of Naples in summer and autumn allow two areas to be distinguished : higher trophic conditions were found in the area along the northwestern coastline. The biological conditions are correlation with these ecological areas. Particular attention was given to Cladocera (Evadne sp., Penilia avirostris) and to Copepoda (Temora stylifera, Clausocalanus sp., Oithona sp.). After having compared the coastal plankton of an open sea area to that of the Gulf, it is believed that knowledge of the hydrology, fertility of the waters, the planktonic population and the physiological needs of its representative organisms might lead to the recognition of different planktonic areas in the neritic province. DICKIE, L. M. and J. C. MEDCOF, 1963. Causes of mass mortalities of scallops (Placopecten magellanicus) in the Southwestern Gulf of St. Lawrence. J. Fish. Res. Bd,. Canad., (20) 2: 451-482. In nine of the years since 1928 there have be~n midsummer mass mortalities of scallops in the southwestern Gulf of St. Lawrence. There is evidence that sudden, groat increases in water temperature sometimes exceeded the upper incipient lethal temperatures of scallops and that these were directly responsible for the more devastating, sudden and widespread mortalities (up to 80 per cent). Unusual and unexplained concentrations of predators, mainly starfish, are considered to have been responsible for several for the slower and less spectacular mass mortalities (up to 25 per cent).
37
DARBYSHIRE,]V[., 1963. Wave measurements made by the National Institute of Oceanography. In: Ocean Wave Spectra, Proc. Conf., Easton, Md., May 1-4, 1961, Prentice-Hall, N.J. 285-291. The National Institute of Oceanography has been making instrumental measurements of sea waves since 1945. An account is given here of wave measurements made in the North Atlantic Ocean and around the coasts of Britain since that time, indicating what records are available and summarising the information that has been extracted from these records. DAVIS, C. C., 1963. On questions of production and productivity in ecology. Arch. Hydrobiol., 59 (2): 145-161. Confusion of terminology and of thought makes it necessary to examine production-productivity theory in some detail. A fundamental dichotomy in concepts lies between the potential rate of formation of organisms in a given area or volume of water under ideal conditions and the actual rate of formation under actually existing conditions. The former is called productivity and the latter production. A second dichotomy applies equally to each of the above : the dichotomy between the circulation of matter and the flow of energy through an ecosystem. There are, then, four fundamental concepts, energoproductivity, energoprodoction, organoproductivity and organoproduction. Each of these in turn is subdivisible into net and gross production (or productivity), and primary, s~ondary, total, etc., categories. In addition, the concepts of yield, standing stock, biomass and organomass are discussed. An appropriate detailed systematic terminology is suggested to be applied to the specific concepts. This is compared with the varying terminologies used by other authors. DAY, J. H., 1963. Polychuete fauna of South Africa: Part 7. Species from depths between 1000 and 3330 metres west of Cape Town. Ann. S. Africa. Mus., 46 (14): 353-371. Twenty-eight species of Polychaeta are described from abyssal dredgings west of Cape Town. The collection includes four new species and eleven new records for this area. Only four of these species are known from depths less than 100 m; the rest are widespread at abyssal depths. There is no obvious Antarctic component. DE ANGELIS, C. M., 1962. Distribuzione ed ¢cologia di alcune specie di Dinoflagellati di acque salmastre. Pubbl. Staz. Zool., Napoli, 32 (Suppl.): 301-314. Some species of dinoflagcllates more generally found in Italian coastal ponds, and their distribution and adaptability to the surroundings are examined. The importance of salinity, temperature and eutrophic habitat are also pointed out. The author considers some morphological variations found specially in Prorocentrum species. Such individual variations never produce a population selected in races, but make the high degree of variability peculiar to the species evident. DE LEONmUS, P. S., 1963. Power spectra of surface wave heights estimated from recordings made from a submerged hovering submarine. In: Ocean Wave Spectra, Prec. Conf., Easton, Md., May 1-4, 1961, Prentice-Hall, N.J., 243-249. The technique of obtaining surface wave records with an inverted echo sounder from a submerged hovering submarine, and some of the errors associated with such a wave measuring system, are discussed. Examples of digital power spectral estimates obtained from recordings arc presented, Significant wave heights obtained by these wave spectra are compared to hindcast values using the Pierson-Neuruann spectra. The agreement is fair. DELLA CROCE,N., 1962. Zonazione zooplanctonica nel Golfo di Napoli. Problemi ecologici delle zone litorale del Mediterranco 17-23 lugiio 1961. Pubbl. Staz. Zool. Napoli, Vol. 32 Suppl.: 368-379. Some features of the superficial waters of the Gulf of Naples in summer and autumn allow two areas to be distinguished : higher trophic conditions were found in the area along the northwestern coastline. The biological conditions are correlation with these ecological areas. Particular attention was given to Cladocera (Evadne sp., Penilia avirostris) and to Copepoda (Temora stylifera, Clausocalanus sp., Oithona sp.). After having compared the coastal plankton of an open sea area to that of the Gulf, it is believed that knowledge of the hydrology, fertility of the waters, the planktonic population and the physiological needs of its representative organisms might lead to the recognition of different planktonic areas in the neritic province. DICKIE, L. M. and J. C. MEDCOF, 1963. Causes of mass mortalities of scallops (Placopecten magellanicus) in the Southwestern Gulf of St. Lawrence. J. Fish. Res. Bd,. Canad., (20) 2: 451-482. In nine of the years since 1928 there have be~n midsummer mass mortalities of scallops in the southwestern Gulf of St. Lawrence. There is evidence that sudden, groat increases in water temperature sometimes exceeded the upper incipient lethal temperatures of scallops and that these were directly responsible for the more devastating, sudden and widespread mortalities (up to 80 per cent). Unusual and unexplained concentrations of predators, mainly starfish, are considered to have been responsible for several for the slower and less spectacular mass mortalities (up to 25 per cent).