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Temperature distribution below oceanic ridge
190
Oceanographic Abstracts
causes damage. Power spectra of Porto Empedocle sea level records show a dominant peak at about 14.6 min and secondary peaks at about 48, 33.6, 25.8, 18.7, 12.2, 9.1 and 7 min. On the basis of a hydrodynamical numerical model, we suggest these are just the eingenperiods of a particular basin, i.e., the submarine basin situated in front of Sicilian southern coast and here called South Sicily Basin. The phenomenon seems to be excited preferentially by the passage of meteorological fronts over the basin. CRAM D. L. and I. HAMPTON," 1976. A proposed aerial/acoustic strategy for pelagic fish stock assessment..L Cons. int.
Explor. Mer, 37 (1): 91-97. Aerial and acoustic observations on Sardinops ocellata shoals in the Southeast Atlantic show that the extreme patchiness of the shoals, the mobility of the fish and their tendency to avoid vessels, may invalidate the results of quantitative acoustic surveys on the stock. It is suggested that these survey errors can be reduced considerably by employing an aerial/acoustic strategy where the aircraft locates and measures the shoal area, and the vessel makes synchronous measurements of shoal thickness and packing density from as many shoals as possible. The combined data provide a direct estimate of stock size. C U R R I E R . G., 1976. Th,~-spectrum of sea level from 4 to 40 years. Geophys. JIR. Astr. Soc., 46 (3): 513-520. Maximum entropy spectrum analysis of 33 tide-gauge records spanning the late 19th and 20th centuries yields persuasive evidence for the 18.6 yr hinar-nodal term and a heretofore undetected solar-cycle signal in sea level. The mean period and standard deviation (sd) of the observations are T L = 18.5 -+ 1.1 and T s = 10.9 -+ 0.6 yr, respectively, and each has an average amplitude of roughly 9 mm. Additionally, an apparent signal of unknown origin with Tu - 6.3 yr and A u = 14 mm is evidenced. CZECHOWSKI LESZEK, 1976. Temperature d~stribution below oceanic ridge. Acta geophys, pol.. 24 (1): 3-13. This paper presents the calculations of the temperature distribution in the vicinity of the oceanic ridge. The velocity field in the convection cell is given by assumption. The heat transfer equation is solved numerically for a steady state. The equation takes into account radiative and lattice heat conduction, radiogenic heat, viscous heating and heat absorption by adiabatic expansion and phase changes. The results confirm the occurrence of phase changes in the ascending material. The calculated values of heat flow agree with measurements only if heat tTansported by hydrothermal circulation in the oceanic crust is taken into consideration.
CZECZUGA B., 1976. Calotenoids content in some crustaceans from the Baltic Sea. Bull. Acad poL Sci. CI. II, Skr. Sci. biol., 24 (6): 349-353. 21 crustacean species from the Baltic belonging to Thoracica, Isopoda, Amphipoda, Mysidacea and Decapoda were studied in respect to their carotenoids content by tl-in-layer and column chromatographies. The following carotenoids were found: a-carotene, ~3-carotene, "),-carotene, 6-carotene,/Lzeacarotene, echinenone, canthaxanthin, cryptoxanthin, isocryptoxanthin, hitein hitein-5,6epoxide, zeaxanthin, isozeaxanthin, violaxanthin, astaxanthin, astaxanthin ester, 4-keto-t~-carotene, 4-keto-7-carotene, 3,4-diketoa-carotene and 3,4-didehydro-c~-carotene. Astaxanthin appeared to be the most common of these and it was found in all the studied species. The next was 4-keto-a-carotene (found in 13 species), then lutein (in 9 species) and astaxanthin ester (in 8 species). Total content of the carotenoids langed from 0.97 in Gammarus duebeni to 254.49 tag/g of biomass in Pontoporeia affinis. DARE P. J. and D. B. EDWARDS, 1976. Experiments on the survival, growth and yield of relaid seed mussels (Mytilus
edulis L.) in the Menai Straits, North Wales. J. Cons. int. Explor. Mer, 37 (1): 16-28. The survival, growth and yield of young mussels relaid on small plots, at densities of 8.75 and 13.25 kg/m 2 five weight, were studied at low-water mark of spring tides in the Menal Straits, North Wales. Populations grew from mean lengths of 27 mm to minimum market size (50 mm) in 15 - 20 months, and to 55 - 58 mm in two years, but good growth was offset by high mortality so that no significant gains in live crop weight resulted. Heavy predation by shore-crabs (Carcinus maenas (L.)) upon mussels smaller than 45 mm shell length was the major factor restricting crop growth. During the first year, mortality of unprotected mussels was very high (70 - 85%), whereas losses within crab-proof cages were significantly less (17 - 41%). Second-year mortality on open plots fell significantly to 22 - 57%, most losses then being caused by storms and bird predators, but that in cages rose to 27 - 54% due to overcrowding and smothering in biodeposits ('mussel-mud'). Dry-flesh biomass (ash-inclusive) of unprotected mussels amounted to 4 - 6% of live crop weight (shell inclusive) and fluctuated seasonally, attaining peak values in late summer and early autumn. Standing crops were usually between 0.4 kg/m 2 and 0.8 kg/m 2, with a maximum of 1.2 kg/m 2. Total production of dry-flesh over the two year growing period was 0.75 - 1.43 kg/m 2, most production (about 69%) occurring in ~pring and summer of the first year. For optimum utilisation of mussel stocks and cultivation grounds the relaid mussels should ~e harvested at peak biomass, in late summer and autumn, and at a smaller size (45 - 50 ram) than at present. DAUMAS R. A., 1976. Variations of particulate proteins and dissolved amino acids in coastal seawater.. Mar. Chem., 4 (3): 225-242. The relationships existing between the protein-containing fraction of particulate matter and amino acids dissolved in seawater were studied in the Gulf of Marseille at different periods of the year. The concentration of particulate proteins was almost zero in
Oceanographic Abstracts
causes damage. Power spectra of Porto Empedocle sea level records show a dominant peak at about 14.6 min and secondary peaks at about 48, 33.6, 25.8, 18.7, 12.2, 9.1 and 7 min. On the basis of a hydrodynamical numerical model, we suggest these are just the eingenperiods of a particular basin, i.e., the submarine basin situated in front of Sicilian southern coast and here called South Sicily Basin. The phenomenon seems to be excited preferentially by the passage of meteorological fronts over the basin. CRAM D. L. and I. HAMPTON," 1976. A proposed aerial/acoustic strategy for pelagic fish stock assessment..L Cons. int.
Explor. Mer, 37 (1): 91-97. Aerial and acoustic observations on Sardinops ocellata shoals in the Southeast Atlantic show that the extreme patchiness of the shoals, the mobility of the fish and their tendency to avoid vessels, may invalidate the results of quantitative acoustic surveys on the stock. It is suggested that these survey errors can be reduced considerably by employing an aerial/acoustic strategy where the aircraft locates and measures the shoal area, and the vessel makes synchronous measurements of shoal thickness and packing density from as many shoals as possible. The combined data provide a direct estimate of stock size. C U R R I E R . G., 1976. Th,~-spectrum of sea level from 4 to 40 years. Geophys. JIR. Astr. Soc., 46 (3): 513-520. Maximum entropy spectrum analysis of 33 tide-gauge records spanning the late 19th and 20th centuries yields persuasive evidence for the 18.6 yr hinar-nodal term and a heretofore undetected solar-cycle signal in sea level. The mean period and standard deviation (sd) of the observations are T L = 18.5 -+ 1.1 and T s = 10.9 -+ 0.6 yr, respectively, and each has an average amplitude of roughly 9 mm. Additionally, an apparent signal of unknown origin with Tu - 6.3 yr and A u = 14 mm is evidenced. CZECHOWSKI LESZEK, 1976. Temperature d~stribution below oceanic ridge. Acta geophys, pol.. 24 (1): 3-13. This paper presents the calculations of the temperature distribution in the vicinity of the oceanic ridge. The velocity field in the convection cell is given by assumption. The heat transfer equation is solved numerically for a steady state. The equation takes into account radiative and lattice heat conduction, radiogenic heat, viscous heating and heat absorption by adiabatic expansion and phase changes. The results confirm the occurrence of phase changes in the ascending material. The calculated values of heat flow agree with measurements only if heat tTansported by hydrothermal circulation in the oceanic crust is taken into consideration.
CZECZUGA B., 1976. Calotenoids content in some crustaceans from the Baltic Sea. Bull. Acad poL Sci. CI. II, Skr. Sci. biol., 24 (6): 349-353. 21 crustacean species from the Baltic belonging to Thoracica, Isopoda, Amphipoda, Mysidacea and Decapoda were studied in respect to their carotenoids content by tl-in-layer and column chromatographies. The following carotenoids were found: a-carotene, ~3-carotene, "),-carotene, 6-carotene,/Lzeacarotene, echinenone, canthaxanthin, cryptoxanthin, isocryptoxanthin, hitein hitein-5,6epoxide, zeaxanthin, isozeaxanthin, violaxanthin, astaxanthin, astaxanthin ester, 4-keto-t~-carotene, 4-keto-7-carotene, 3,4-diketoa-carotene and 3,4-didehydro-c~-carotene. Astaxanthin appeared to be the most common of these and it was found in all the studied species. The next was 4-keto-a-carotene (found in 13 species), then lutein (in 9 species) and astaxanthin ester (in 8 species). Total content of the carotenoids langed from 0.97 in Gammarus duebeni to 254.49 tag/g of biomass in Pontoporeia affinis. DARE P. J. and D. B. EDWARDS, 1976. Experiments on the survival, growth and yield of relaid seed mussels (Mytilus
edulis L.) in the Menai Straits, North Wales. J. Cons. int. Explor. Mer, 37 (1): 16-28. The survival, growth and yield of young mussels relaid on small plots, at densities of 8.75 and 13.25 kg/m 2 five weight, were studied at low-water mark of spring tides in the Menal Straits, North Wales. Populations grew from mean lengths of 27 mm to minimum market size (50 mm) in 15 - 20 months, and to 55 - 58 mm in two years, but good growth was offset by high mortality so that no significant gains in live crop weight resulted. Heavy predation by shore-crabs (Carcinus maenas (L.)) upon mussels smaller than 45 mm shell length was the major factor restricting crop growth. During the first year, mortality of unprotected mussels was very high (70 - 85%), whereas losses within crab-proof cages were significantly less (17 - 41%). Second-year mortality on open plots fell significantly to 22 - 57%, most losses then being caused by storms and bird predators, but that in cages rose to 27 - 54% due to overcrowding and smothering in biodeposits ('mussel-mud'). Dry-flesh biomass (ash-inclusive) of unprotected mussels amounted to 4 - 6% of live crop weight (shell inclusive) and fluctuated seasonally, attaining peak values in late summer and early autumn. Standing crops were usually between 0.4 kg/m 2 and 0.8 kg/m 2, with a maximum of 1.2 kg/m 2. Total production of dry-flesh over the two year growing period was 0.75 - 1.43 kg/m 2, most production (about 69%) occurring in ~pring and summer of the first year. For optimum utilisation of mussel stocks and cultivation grounds the relaid mussels should ~e harvested at peak biomass, in late summer and autumn, and at a smaller size (45 - 50 ram) than at present. DAUMAS R. A., 1976. Variations of particulate proteins and dissolved amino acids in coastal seawater.. Mar. Chem., 4 (3): 225-242. The relationships existing between the protein-containing fraction of particulate matter and amino acids dissolved in seawater were studied in the Gulf of Marseille at different periods of the year. The concentration of particulate proteins was almost zero in