The respiration rates of copepod larvae and a ciliate (Placus sp.) from a tropicalsea were measured with an oxygen electrode method. The general range of body size ofthese animals was 40-161 μm (diameter equivalent to a sphere), and the respiration ratemeasured was 0.00076-0.00176 34μl O₂ (animal) ^-1h^-1 (or 2.02-9.05μl O₂ (mg wet weight) ^-1h^-1) at25.5-29.2°C. There was no marked difference observed between the respiration rates ofcopepod larvae and the ciliate. The respiration rates obtained here are relatively higher thanthe rates of other similar sized protozoans found in the literature, but lower than the rateextrapolated from larger planktonic copepods in tropical seas.
The present results and other information available on microzooplankton biomass suggestthat microzooplankton respiration is of near equal importance to that of net zooplankton inthe study of energy flow through tropical, pelagic ecosystems.

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Long ocean waves with periods of several minutes (surf-beats) were observed ata marine observation tower. We have analysed time series data of an envelope of incidentswell, long period current velocity and surface elevation fluctuations. Current velocity wasmeasued by an electromagnetic flow meter. Surf-beats amplitude H^(l) is shown to be proportionalto 3/2 power of incident swell amplitude H ^(L) , and decreases with increase of depthh in proportional to h-1/2 such that H ^(l) H ^(s) (H ^(s) /h) ^1/2. Frequency energy density function PLL (f) of surface elevation had two dominant peaks whose frequencies were highly stablethrough the entire observational period. Cross-spectral analysis suggested that those peakscorrespond to traveling edge waves caused by the excess momentum and mass flux in thesurf zone. The forced long ocean waves predicted by LONGUET-HIGGINS and STEWART (1964) was ditected. Phase-shift and wave height of the wave with respect to those of incidentswell envelope are shown to be in remarkable agreement with the predictions.However the forced long wave is only a minor component in the total energy of surf-beats.Current fields are shown to be largely composed of non-surface modes.

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The nature of the autocovariance function and power spectrum of time series ofspike-array type is discussed: As the spacing of spikes is not easily seen directly in powerspectrum, prudence should be exercised in interpreting the gradient spectrum of oceanicfine-structure. We calculated the autocovariance function and lag joint probability density ofthe record of the vertical profile of the vertical temperature gradient measured in the San Diego Trough. The results obtained support the results of the bispectral analysis in theprevious paper (NAGATA, 1978) that the predominant length scale of about 5 m has twomeanings: spacing of the spikes and wavelength of a sinusoidal wave. The results seem toshow the existence of n: ernal waves having a vertical wavelength the same as the spacingof the spikes or the thickness of the homogeneous layer in the oceanic fine-structure.

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Experiments of sorption of Mn, Co, Ni, Cu and Zn on manganese oxides, hydratedferric oxide, Na-montmorillonite and treated red clay are carried out in connection withthe mechanisms by which transition metals are removed from seawater in marine environments.
The order of sorption affinities of transition metals for Na-montmorillonite, treated redclay and hydrated ferric oxide is Mn<Co<Ni<Zn<Cu, although their distribution coefficientsfor hydrated ferric oxide are about two orders of magnitude larger than those for Na-montmorilloniteand treated red clay. The distribution coefficients of manganese and cobalt formanganese dioxides are much larger than those for hydrated ferric oxide, and the order ofsorption affinities for manganese dioxdes is Ni<Zn<Co<Mn≤Cu.
From the distribution coefficients of transition metals for manganese and iron oxides, andsilicate minerals, it is inferred that manganese oxides play a more important rolethan ironoxides and silicate minerals in removing transition metals from seawater and interstitialwater in deep-sea environments.

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A theory of the coastal Kelvin wave is presented in which the pressure is assumednot to be hydrostatic. The results show that the non-hydrostatic Kelvin wave is dispersiveand that the e^-1 decay distance of the wave amplitude from the coast decreases as the wavelength becomes shorter. Similar conclusions can be drawn on the equatorial Kelvin wave.

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Particulate matter was collected in the Bering Sea and the northern NorthPacific Ocean during the cruise of R. V. Hakuho-maru, Ocean Research Institute of TokyoUniversity in summer of 1975. The particulate matter was analyzed for organic carbon andnitrogen, chlorophyll α and amino acids.
The concentrations of particulate organic carbon and nitrogen were measured with therange of 16-422 μgCl^-1 and 1-85 μgNl^-1, 19^-186 μgCl^-1 and 1-26 μgNl^-1, 46^-1, 038 μgCl^-1 and6-79 μgNl^-1 and 19-246 μgCl^-1 and 2-25 μgNl^-1 in the Oyashio, the Deep Bering Sea, thecontinental shelf of Bering Sea and the northern North Pacific, respectively. Particulateorganic carbon and nitrogen decreased with depth throughout the areas. The average concentrationsof organic carbon and nitrogen in the entire water column tended to decrease inthe following order; the continental shelf>Oyashio>northern North Pacific>Deep BeringSea.
C/N of particulate matter varied in the range of 3^-15 (7 on average) in surface watersthroughout the areas and these values tended to increase with depth to 5-20 (11 on average) in deep waters without significant regional variability.
Linear regressions between chlorophyll a and particulate organic carbon in the euphoticlayers indicate that detrital organic carbon accounted for 34.2, 44.9, 49.1 and 25.2 % of particulateorganic carbon in the Oyashio, the Deep Bering Sea, the continental shelf and thenorthern North Pacific, respectively.
Particulate amino acid was determined in the range of 10.3-78.0 μgl^-1, 104-156 /μgl^-1 and10.4-96.4 μgl^-1 in the Deep Bering Sea, the continental shelf and the northern North Pacific, respectively. Aspartic acid, glutamic acid, serine, glycine and alanine were found as dominantspecies of amino acid of particulate matter.

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[in Japanese]

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