Now, our aim in the coastal reconstructing must be the creation of ecological surroundings in the coastal area. The seawater purifying facilities that utilize oxidizing microbes in rock bed are expected to create ecological surroundings in the seashore. At first, we investigated changes in the water quality in the coastal sea with the rubble-mound breakwater. And we built a simulation model for estimation of purifying performance of each seawater purifying facility. Secondly, we estimated the effect of purifying seawater in the closed and polluted sea with the seawater purifying facility by our simulation. From the results of simulation, we concluded that these facilities could purify polluted seawater and that, particularly, seawater purified by the rubble-mound breakwater could create water front area for marine recreation.

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In Japan, we have to reduce the environmental impact caused by recycling, because there will become serious recycling age by the execution of the law regarding with vessels and packages. In this paper, we applied LCA method fundamentaly, we assessed the environmental influence with collection and recycling system of the waste packagzings by using environmental indicators that were got by weighting to the amount of the environmental load. And we found the most effective collection and recycling system for the packagings through the examination about the environmental impact caused by the packagings collection and recycling systems in the subject city.

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An investigation was made of the way of runoff non-point pollution control with storm-water reservoir for flood control in order to improve water quality in the public water body in urban area. We suggested separating the one storm-water reservoir for two reservoirs functionally. One is the reservoir for non-point pollution control and the other is the reservoir for flood control. “First flush” of runoff non-point pollution loads flows into the first reservoir and peak runoff storm water flows into the second reservoir. These “Two-step reservoirs” are effective for non-point pollution control when we establish adequate volume of reservoirs and height of inflow weir. And “Two-step reservoirs” are effective to reduce combined sewer overflows.

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Life cycle assessment (LCA) was conducted for the Fukuoka Island City Project being undertaken in the eastern area of Hakata Bay. The analysis included coastline construction and reinforcement, dredging and reclamation works, and construction, operation and maintenance of the facilities and buildings to be built on the island. The inventory analysis for life cycle energy consumption (LCE) and carbon dioxide emission (LC-CO₂) was accomplished by breaking down the construction processes and materials into parts for which relevant energy data were available. As for the items for which relevant energy data were not available, values reduced by I-O analysis were utilized as proximate values. Thus the environmental loading for each individual process was determined and the cumulative total was calculated.

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Based on detailed field observation, runoff characteristics and runoff loadings of fungicides to a river from paddy fields were investigated in this study. In addition, the authors calculated the runoff rate of pyroquilon of which applied amount was obviously grasped. Behaviors of pyroquilon which differed from those of other three kinds of fungicides (flutolanil, isoprothiolane, pencycuron) in a paddy fields and rivers were examined in detail. Using a fugacity model, the distribution rate of pyroquilon in each phase was calculated. It is clarified that pyroquilon is one of low degradable fungicide and the grater part of the applied pyroquilon residues in a water phase. According to the results, the runoff loadings of the fungicides from paddy fields caused by deficiency of water management were clearly characterized.

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A combined biological activated carbon (BAC) and biological zeolite (BZ) reactor was applied to treatment of scrubber-washed wastewater from sludge drying process. Successful treatment performance of both organics and nitrogen was accomplished. Appropriate nitrogen loading rate for fine and stable treatment was shown to be less than 7mgNOx^--N·(gGAC·d)^-1 for denitrification in BAC tank and less than 4mgNH₄⁺-N·(gZeolite·d)^-1 for nitrification in BZ tank. DOC/NOx^--N loading ratio to BAC tank was required to be more than 2.0mgDOC·(mgNOx^--N)^-1 for successful denitrification. ORP control in the anoxic tank in the range from -150 to -250mV was shown to be also important.

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The objective of this study is to establish the methodology of toxicity test of detrimental substances using conchospores and their germlings of Porphyra yezoensis. Release of conchospores from mature free-living conchocelis took place after 7 days when the culture transfered from 23°C to 15°C temperature conditions with 10hL:14hD in 1/20PES medium, and 80% of conchospores were released for first 3 hours when the light condition was changed from off to on in a day. As substrata to be adhered conchospores, the glass plate was the most adequate and concerning the method of adhering conchospores, natural sedimentation of conchospores onto the glass plate was the most adequate. Adhesion and survival ratios of conchospores were constant, even if the date and the number of collecting conchospores were different.

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The purpose of the management of coastal environment including the fisheries stocks in the Seto Inland Sea by using a shallow sea ecological model, which can predict to the inflluence on fisheries stocks caused by human impact factors, such as oxygen deficient water mass and loading abatement were discussed. According to annual variation of fisheries catchment, the pressure of that was shown to the large in 1982. From the simulated result of fisheries stocks, it was indicated that the distribution of them was showed relatively diffluence between the western sea and the eastern sea in the Seto Inland Sea. Otherwise, it seemed to increased the distribution of fisheries stocks as demersal-fish and benthos in the Seto Inland Sea by means of loading abatement.

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We theoretically considered the distribution of ⁶⁰Co and ⁸⁵Sr to ion exchangers from solution that contained Ca⁺⁺ and Mg⁺⁺ simultaneously as major cations, and derived a equation that expresses the quantity of ⁶⁰Co or ⁸⁵Sr adsorbed to an ion exchanger under the influence of these two major cations. Then we performed column experiments to determine Kd values of these two radionuclides in solutions containing Ca⁺⁺ and Mg⁺⁺ simultaneously to three ion exchangers, Amberlite IR-120B, Green sand and KUR sand. Experimental results of this study certifies that the equation is applicable to estimate the influence of Ca⁺⁺ and Mg⁺⁺ on adsorption of tracer ⁶⁰Co or ⁸⁵Sr.

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This paper presents the diagrams of the nitrogen (as nitrate, ammonium and organic) and phosphorus material cycle in Japan, in 1992. These diagrams are expected to give the basic database to whoever study the improvement on the sustainablity of the current material cycle.
Various data sources, concerning such as food distribution, livestock food, waste, feces, sewage, water quality, water flux, fertilizer etc. are utilized.

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