In this content, document information on environmental resources of the coast and the shallow sea area was collected and arranged. Moreover, the trend of the ecosystem management technology was considered based on the number of documents according to the specialized field and the research object. As a result, the concern for the environmental preservation of environmental resources and the fishery obtained from the sea area was guessed to be high. Therefore, the proposal to the content of the investigation and the research of living aquatic resources in the future was followed.
Living aquatic resources are bases of continued development of the fishery industry, and it is not possible to lack it for man who uses them as food and a raw material. Therefore, it is important to develop the technology of the circulation type that centers on maintenance of living aquatic resources and the continued use as a technology of the management of the ecosystem of living aquatic resources. However, the distribution situation and the amount of a necessary resource are not understood adequately, and are not clear the level which the resource should maintain to manage living aquatic resources under the present situation. Therefore, it will be necessary to grapple with the problem of the resource control concretely by aiming at enhancement and strengthening the investigation and the research of the resource control, and setting the resource recovery target in the future.
Our country can make the best use of the advantage that surroundings in the country are enclosed in the sea area, and food resource do the circulation use efficiently by continued use of the coast and the shallow sea area. Therefore, the fishery industry of the coast and the shallow sea area is promoted as living thing industry. Promoting use as the biomass and circulating use of a useful element become important.

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It may be possible to recover the qualities of seawater and sediments using the natural purification actions. This means that the breeding of microorganism and seaweed is needed in coastal regions. Therefore, this study examines two materials for the recovery of the natural purification actions, and also a filtering-vessel for purification of seawater.
The results are as follows;
1) Carbon fiber was used to promote the breeding of microorganism and phytoplankton, etc. The COD was decreased by the biological actions and a large amount of P and Fe was absorbed in the bunch of carbon fiber. Many kinds of seaweed were also found on the bunch of carbon fiber.
2) Steel slag was used to control the amounts of H₂S and P from the sediments. Steel slag can also be used as ground base for seaweeds.
3) A full-scale filtering vessel was used to clean up seawater. The COD and SS were effectively removed from the seawater.

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It is possible that around 2030, the entire world will be facing a food crisis. Japan will have to cope with such a crisis using marine resources. In particular, since the fisheries environment in shallow seas offers high biological production, it is essential that the environment be maintained to an absolute high standard. However, in Japan, seaweed beds in shallow seas have been disappearing because of environmental destruction, water pollution, and so forth. Therefore, the development of environmental preservation and restoration of the seaweed beds in shallow seas are important Some of the reasons for environmental destruction are: Ocean dumping of fly ash and clinker ash, the waste from thermal power generations, and sand extraction and gavel extraction for aggregate from shallow areas.
This paper reports on the development of bio-adhesive waste-use-concrete using FA, CL, zeolite, which is waste from locally-established industry and waste molding sand containing Fe. If this material can be realized, conserving and restoring production environments in shallow seas and the recycling of waste would be feasible.
In the first experiment, the durability and the strength of five mortar test pieces were measured to form a seaweed bed. The five test pieces were Plain (normal mortar), FA & CL, FA & CL+zeolite, FA & CL+molding sand and FA & CL+zeolite+molding sand. In the second experiment, harmful materials, extracted from FA & CL mortar test pieces by elution test were investigated to examine their influence on the marine environment and marine life.
Furthermore, to investigate how well aquatic life can grow on the mortar test pieces, the mortar test pieces were immersed in seawater, and then biomass of biofilm was measured the quantity of ATP, chlorophyll a, and FDA decomposition activity.
The results of the first experiment showed that recycled waste-use-concrete containing FA, CL, molding sand and zeolite had sufficient strength for seaweed beds.
The results of the second experiment showed that the test pieces were also safe for seaweed beds since there was hardly any trace of heavy metals or organic phosphorus detected.
The results of last experiment were: (1) The quantity of ATP of three types of zeolite-molding sand system pieces (FA & CL+zeolite, FA & CL+molding sand and FA & CL+zeolite+ molding sand) was almost equal to the Plain or larger than the Plain.(2) The quantity of chlorophyll a was FA & CL+molding sand>FA & CL+zeolite > FA & CL+zeolite+ molding sand=FA & CL > Plain.(3) FAD decomposition activity was roughly the same as that of the Plain.
From these results, bio-adhesion to waste-use-concrete containing FA, CL molding sand as Fe and zeolite were satisfactory, and in particular, waste-use-concrete containing FA, CL and molding sand as Fe was algae flourished remarkably. Thus, it is feasible to use waste-use-concrete for artificial seaweed beds.

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The temporal and spatial patterns of species composition and the abundance of fish in the mangrove estuaries of the Gesashi River on Okinawa Island, the Shimajiri River on Miyako Island, the Nagura River on Ishigaki Island and the Urauchi River on Iriomote Island were studied during August, from 2000 to 2002. Fish samples were collected by cast nets, hand nets, and angling. In total, 5,747 individuals representing 13 orders, 47 families, 104 genera and 155 species were recorded from four mangrove estuaries. The number of species was found to increase from north to south. In terms of individual numbers, several species represented dominant key species, which comprised over 50% of the total number of individuals collected in each estuary. In terms of the number of species per family, the most dominant family was the Gobiidae in each river and accounted for 25.5% of the total number of species that appeared in the Gesashi River, 30.2% in the Shimajiri River, 40.7% in the Nagura River, and 38.1% in the Urauchi River. The diversity of fish species found in the Okinawan mangrove estuaries was considered to be similar to or greater than those in other tropical regions.

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The potential of near infrared (NIR) spectroscopy to determine Cl^- concentration of concentrated-seawater was investigated. The NIR spectra (1100-1800nm) of concentrated-seawater with different Cl^- concentrations were measured at three sample temperatures of 5°C, 25°C and 40°C. Calibration model with a temperature-correction function was developed using the partial least squares (PLS) regression method. The model obtained from the second derivative spectra gave a correlation coefficient of 0.99 and standard error of prediction of 1.66 g/l for Cl^-concentrations of concentrated-seawater.

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The chlorine resistance of reverse osmosis membranes was investigated with a cross-linked aromatic polyamide composite membrane, an N-substituted polyamide composite, and a cellulose acetate asymmetric. The degradation was observed as the increase in both solute and water permeation coefficients, which can be expressed as functions of a quantity of chlorine concentration to the Xth power times the chlorine exposure time. It was found that values of X are in the range of 0.5-0.7 for the cross-linked aromatic polyamide composite, 1.2 for the N-substituted polyamide composite, and 1.5 for the cellulose acetate asymmetric. The value of X seems closely related to the degradation mechanism. In the case of rapid degradation, the degradation might be mainly caused by chlorination, and the value of X should be close to 0.5. On the other hand, in the case of slow degradation, the degradation might be mainly caused by oxidation, and the value of X should be close to 2. The morphological and structural changes due to the chlorination degradation were observed using electron microscopy and ESCA, and the membrane transport characteristic change was discussed from the observed results such as membrane thickness, its looseness, and its fixed charge density.

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To provide fundamental information for the design of a response plan when accidental spills of an emulsified fuel (Orimulsion) occur, a laboratory-scale study was carried out On the fuel's behavior in saline, quiescent waters. The emulsifier in the fuel was made ineffective, when the fuel was dispersed in saline waters. The degree of ineffectiveness increased with an increase in salinity of the water. As a result, the droplets in Orimulsion coalesced with each other shortly after being dispersed in saline water. Most of the coalesced bitumen drops were finally re-floated when dispersed in seawater. This re-floated amount depended on the salinity of the saline water. Although in the saline water with a density from 1.012 to 1.015g/cm³ at 15°C, the re-floated part of the bitumen drops dominated, there was also found a significant part deposited on the floor. This deposited part of the bitumen in Orimulsion was relatively unsticky, and was considered to be the asphaltic fraction of the bitumen. The presence of this sinking part in the bitumen will make the behavior of Orimulsion further complicated when it is spilled in an estuary area.

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