Experimental research was established on the influence of temperature on the anaerobic degradation characteristics of highly concentrated organic wastewater when permeating the soil. A column experiment, using a column which contains sand at a depth of 50cm, was made at the temperature of 10°C, 20°C and 30°C over a 44 week period. Under the condition of 10°C, the removal rate of COD was about 3% due to the accumulation of volatile fatty acids. Under the condition of 20°C and 30°C, the generation of methane was observed and the removal rate of COD was about 90%. The removal of COD proceeded in the same way under the condition of 20°C and 30°C.

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The purpose of this paper is to propose an evaluation method for coastal environmental restoration technologies using an ecosystem modeling technique. An ecosystem model of artificial lagoon, which is one of the environmental restoration technologies, has been developed based on field surveys at Rinku Park in Osaka Bay. Carbon and nutrient fixation effects of the artificial lagoon have been estimated as an index of the restoration efficiencies. The results of estimations have shown that the total fixation effects decreases year by year because of the accumulation of the sedimentary organic matter, and the fixation efficiency increases with decreasing the depth of the artificial lagoon.

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Many types of artificial reefs have been developed and settled to create fishery ground for the production enhancement in marine areas. There are many issues to be clarified about the suitable installation of artificial reefs, such as the relation between flow conditions and the biological effect of them. In this paper, a set of technologies newly developed to restore marine biological environment is introduced. It consists of a numerical simulation to select out the most appropriate area for marine habitat restoration and a new artificial reef that embodies multiple functions. The set of technologies was applied to two coastal areas of different characteristics and was verified to improve biological environment.

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In this study, we propose the support system to select the most useful development project for the natural environmental preservation and existence of species from some plans. We first describe the usual simulator and outline of the cellular automaton and the group method of data handling. Then we explain the structure and dynamics of proposal hybrid system which includes the cellular automaton and the group method of data handling. In simulation, finally, the effectiveness of proposal system is shown by applying the selection problem of development strategy.

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LCA was applied to the wooden bridges constructed by creosote- and CCA-impregnated wood. Results were compared with those of concrete and steel bridges, and environmental performance of preservative-treated wood was discussed. Conclusions obtained in the current assessment are as follows: 1) Wooden bridges (creosote and CCA) are most advantageous scenarios for climate change, photo-oxidant formation, acidification, and eutrophication. However, wooden bridge (CCA) is disadvantageous scenario for human toxicity and ecotoxicity; 2) Main reason of disadvantage of wooden bridge (CCA) is the discharges of As, Cr, and Cu to the environment in service and when CCA-impregnated wood is incinerated; 3) Effective reduction in toxic impacts of CCA-impregnated wood can be achieved by collection of CCA components at the incineration site.

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The proposed heat transfer theory of the Bore-hole Heat Exchange System (BHES), incorporating the thermal interaction between a bore-hole heat exchange pile and groundwater flow, could reproduce the measured fluid temperature distribution along a heat exchange pile during the operation and in the following fluid temperature recovery period. From the numerical simulation, the proposed model predicted the enlargement and disappearance of groundwater temperature variation associated with the operation of heat injection and extraction, and showed that the surviving period of the temperature variation is shorter than two months after ceasing the operation. Finally it was seen that the performance of heat injection and extraction is remarkably improved with the increase in the Peclet number, Pe, at the upstream side element contiguous to the heat exchange pile for Pe≤5.

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Arisaema ehimense is morphologically intermediate between A. serratum and A. tosaense. The species is very similar to that of their artificial hybrid, which suggests a hybrid origin between two species. However both species rarely grow in same areas. And furthermore flowering period of A. serratum is earlier than that of A. tosaense. Therefore it has been considered that there is no opportunity of hybridization between the species. In this study we observed the flowering period of the two species at Ohshima in Yamaguchi Pref. where both species grew at same area. There we found that a part of the A. serratum could hybridize a part of A. tosaense. This fact shows that hybridization ought to have occurred between two species. This is an example of hybridization which could generate new species. It also suggests that we need to consider the importance of the habitats where more than two kin species are alive for a new species birth area, and must preserve them.

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The process of risk communications is important for designing future water supply systems. The purpose of this study is to investigate the structure of customer's risk perception on water supply system. A queationnairing for the people in Osaka prefecture by a semantic differential method was carried out. A structural model of constructs concerning risk perception of water supply system was developed by confirmatory factor analysis. It was shown that the amount of information, unknown risk, and sense of security was linked by a causal structure. It was pointed out that sense of security does not always increase by knowing bettter on the quality of tap water.

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Material and heavy metal balance in a MRF of household bulky waste were estimated. Nine truck-loads of waste were shredded separately, and recovered fractions of materials were weighed. Metal contents were analyzed for every waste material. By composition analysis of oversize and undersize of a Trommel separator, up to 40 percent of combustible materials was transferred into undersize which is disposed of in landfill, while transfer rate of incombustible material into oversize was less than 20 percent. Mass balance calculated based on the number, composition, and average weight were well correlated with measured values, but weights were underestimated. Finally, contribution rates of manufactured goods for heavy metals in bulky waste were estimated.

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An experimental structure was established at Komatsushima port in Tokushima Prefecture to study the environmental problems of vertical structure in port and harbor. Organisms inhabiting intertidal and subtidal zones of the structure are expected to play an role to reduce the amount of organic matter accumulated onto the sea bottom. The results suggested that concentration of organic matter in the deposited seston decreased at the bottom in front of the experimental structure. Accumulation of organic matter on the bottom, however, differed between the types A and B with different depths of flat bottom substrate, indicating that a flat bottom substrate shallower than DL-2m should be designed.

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