A Continuous experiment on the hydrogen fermentation of glucose was conducted to investigate the relationship between the hydrogen productivity and the microbial community of the mixed micro-flora. A total of five different kinds of inoculums including digested sludge, heat treated digested sludge, activated sludge, compost and a special consortium were used as the seeds for five chemostat-type reactors. Each reactor was continuously operated at the same condition of 35°C, a hydraulic retention time 12 hrs and a pH5.5 using a medium with glucose of 10000 mg/L for over two months. It was found that the fermentative pattern and the hydrogen productivity depend on the initial inoculums. The analysis results of PCR-DGGE method and DNA sequence indicates that Clostridium acetobutylicum and Clostridium pasteurianum were the important bacteria in hydrogen fermentation for obtaining a high H₂ yield.

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With economic globalization, countries are strengthening interdependence of environmental loads through trade of goods and services. While some countries are transferring economic activities with higher environmental loads to foreign countries, other countries are enjoying economic growth by specializing in the production of export goods that embody larger environmental loads. Analysis of this international interdependence is useful for better understading of the common but differentiated responsibilities of countries to protect the environment. This paper quantifies the transaction of energy, CO₂ and land embodied in goods and services traded in the Asia-Pacific region for the years of 1985, 1990 and 1995. The result demonstrates the largest flow of environmental loads is formed centering the United States and China. China, in particular, is achieving economic growth by taking over the responsibilities for CO₂ emissions.

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The development characteristics of restored and created intertidal flat ecosystems were examined by using data from an indoor mesocosm experiment and field studies conducted at a created intertidal flat in Mikawa Bay. The drastic elevation change in the created intertidal flat caused a decrease in macrofaunal abundance, preventing self-stabilization of the ecosystem. Macrofaunal species richness reached a dynamic equilibrium between two and greater than six years, indicating that long-term monitoring is necessary to assess restoration success. The rate of ecosystem development appeared to be determined by the efficiencies of larval recruitment and adult access to the site.

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Because the Japanese archipelago is surrounded by sea and important social-economic activities concentrate in areas below sea-level, it is prerequisite to predict impacts of sea-level rise on groundwater systems in coastal aquifers. For applying numerical models to areas with inclined land surface which allows storage of surface water, we developed a simulation code, SIFEC, based on coupling of finite elements for density-dependent flow and method of characteristics linked with finite elements for mass transport. To improve accuracy for interpolating concentrations in solving transport equation, single-step reverse particle tracking is used with biquadratic interpolation scheme. Accuracy of the technique was compared with results of experiments and other simulation techniques, and excellent results were obtained.

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Reservoir obstructs gene flow of stream invertebrates along a channel, which takes place via larval drift and adult flight. It may result in genetic differentiation between above and below reservoir, which would reduce genetic diversities in fragments. Gene flow across a reservoir may be more strongly obstructed if the area of standing water is larger. Using RAPD, we investigated the genetic structure of Stenopsyche marmorata populations found above and below the reservoir, and the reference stream of 6 reservoirs in small to large water surface area. As a result, out of the 6 reservoirs, significant genetic differentiations were detected in the biggest 2 reservoirs with an area of standing water larger than 3.27 km². However, these genetic differentiations did not result in the reduction of genetic diversities in the fragments.

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The restoration of damaged mire is important as it comprises of unique habitat which rarely found anywhere else. Among many techniques, damming has gained widespread use in mire restoration. However, its effect on the restoration of water quality has yet to be examined, because the objectives of damming have been mainly hydrological. This study attempts to clarify how dams affect the water quality in a bog-mire wetland by comparison with previously gathered data from a point of natural conditions and two points of disturbed conditions. The effect of the dams in re-establishing the natural vegetation was also studied.

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