In thisfind decade and towards theendof 20th century, a number of satellite sensors capable of providing data on radiance from the sea surface are destined to be launched, enhancing opportunities of synoptic observation in the coastal zone. Japan is now at a stage of launching a sensor as well as planning of data reception from relevant sensors. This paper discusses some of the key factors in view of full utilization of coastal zonecolorremotesensing in Japan. Firstly, a peculiarity of the regional atmosphere which may lead erroneous satellite estimate is indicated. Secondly the paper introduces the concept of dominant spatial scales in the marginal seas of Japan which will help interpreting satellite-derived information field. The paper also attempts to provide the technical concepts which may underline the efforts in bridging the gap between the informationsource and targets.

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The variation of concentrations of elements with growth in the calcitic outer shell layer of Mizuhopecten yessoensis (Jay), living in Mutsu Bay, northernJapanwas for the first time presentedin detail.The variation was clarifiedfor the contentsof elevenelements： Li, Na, K, Mg,Sr, Ba, Fe, Mn, Al,B and P. The variation patterns make to divide the elements into the following four groups： (1) magnesium, strontium, barium, iron and manganese； showing the seasonal variation pattern. These are occupied in the lattice sites in the calcium carbonte's crystal. (2) lithium and sodium; showing the seasonal variation, pattern with reverse pattern for the former group. These are associated with inclusions and/or organic matrices. (3) aluminium, pottasium and phosphorous； showing a random variation pattern. These are originated from foreign detrital grains. (4) boron； showing no seasonal variation pattern and partially high content Boron may be exsited as an other phase with small garains. The difference among these variation patterns originates in the difference of phase within shell. The variations of the firstand secondgroupscan beexplained by ”optimum condition model” proposed herein.

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A study of fish scale, along with otolithes, backbones and other hard parts,yields ecological information such asthe source river, the rate ofgrowth, aswell asthe fish age. Consequently, the analysis ofscale pattern has been widely used to determine the fish age and their stock origins. In the present paper, an analytical method ofdetermining the stock discrimination ofchum salmon caught from different origins using scale patterns is developed. The analysis has been made by utilizing an auto-correlation coefficient and power spectrum as a function ofthe circuli number.The authors employed a a^scriminant function incorporated with power specialized values of amplitude of circuli pattern data as explanatory variables. Fish from four different rivers were grouped with an averageaccuracy of 88 %.Thescale samples used in the analysis were collected from four rivers (RTokachi in Hokkido, R. Anadyr in Russia, R. Yukon in Alaska andR.Fraser in Canada.) ( keywords: chum salmon, scale pattern, circuli pattern, stock origin, spectrum analysis, aUscriminant function.)

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Hard tissues such as fish scale and otoliths are continuouslydeposited from fish birth to its death. Therefore hard tissues are recording information that fish experienced. In order to investigate the infomation, scale circuli and trace elements in otoliths of red sea bream, Pagrus major, were analyzed. Scale circuli werecountedto investigate a relationbetween circuli deposition and temperature. Trace element concentration were analyzed by Particle Induce X-ray Emission (PDOE). These studies showed that there were some relations betweenhard tissuesformation and ambientseawatertemperatures.

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Ocean wave image data obtained by ERS-1/AMI (image mode) are analyzed in this study. Ocean wave directional spectrum and other ocean wave parameters are derived by using fast Fourier transform (FFT) and a series of modulation transfer function (MTF) corrections. The instrument modulation transfer function (IMTF) is estimated by the least square fit method in the range and azimuth direction separately. The significant wave height is estimated based on the azimuth smearing effects and compared with buoy data. Finally the integral of ocean wave directional spectrum derived from ERS-1/AMI data is compared with buoy data and the results of numerical predication. The difference of the spectrum in the high frequency range are considered to be due to the azimuth attenuation or noise removal during data processing.

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The possibility of reconstructing Sea Surface Temperatures (SSTs) when the sea surface is masked by clouds from the satellite sensor in aNOAA/AVHRR image by asuccessive correction method is investigated. The reconstruction is carried out after adding artificial clouds to acloud-free image. Two methods of masking SST data by addying artificial clouds to an image are chosen in the present study. In the first method, the shape of an artificial cloud is assumed to be acircle. In the second method, that is assumed by simulating cloudy regions in other images. The resulting SST field detected appears to be similar to the SST field in the original image. Even though the present methodology is quite simple, the results obtained are encouraging.

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Aquatic microorganisms are thought to indicate environmental conditions of their habitats. Both microbial biomass (standing stock) and microfloral composition are closely related to the degree of aquatic pollution such as eutrophication, and to the trophic structure of aquatic biological communities. This article briefly reviews the use of microorganisms as environmental markers to characterize thier natural habitats, taking examples from: (1) eutrophication gradients in coastal waters; (2) hydrothermal plumes; and (3) a deep-sea biological community associated with whale skeleton. Among the microbial environmental markers, the applicability of fatty acid analysis that suggests the possible in situ microbial activity is discussed.

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In order to analyze the water quality, especially COD, T-P and T-N of Tokyo Bay in summer, the hydrodynamical and ecosystem coupled model we have developed was applied. The stationary state results could be obtained over 100 days time integration. For the phytoplankton abundance, COD,T-P, T-N, and inorganic nitrogen concentrations, the model could reproduce the realistic values except an inorganic phosphrous concentration whenwe adopted phytoplankton cellcomposition ratio (N/P ratio by weightin the model) to be 14in place of 8. The discrepancy could not be improved, even if we gave 10times larger phosphrous relaese rate from the sea bottom than standard rate. It maybe improved if weconsider the cell quota mechanism or different decomposition rate of organic matter for nitrogenand phosphrous. The DOC concentrations in the model showed lower values than the ones in the observations. It was implied that when the lowerdecomposition rates of DOCand POC, and changing the POC/DOC ratio in the loading from land were considered, the discrepancy could be reduced. The zooplanktonbiomass distribution showed the influence of fresh water distribution, that is, theinfluence of zero value attheriver boundary. The dominance of physical processes such as diffusion and advection compared to biological processes such as zooplankton growth rate couldbe plausible reason. In phytoplankton case, suchproblem does not occur because of biological processes dominance (high turnover rate).

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