The regional variation in aquatic organisms by water region is an important topic, especially in the process of segmenting water areas to determine environment standards for the conservation of aquatic life. This study demonstrates a method to analyze the regional characteristics of freshwater fish fauna, using multivariate analysis of fish assemblage structure. Applying this method, the analysis was conducted on a total of 47 fish species recorded in field surveys and drawn from existing literature surveys conducted in the Naka River in Fukuoka, Japan, which were then classified into five groups. The factor involved in the classification were explained as the habitat altitude and the types of biological life cycle. By comparing to the indicator species provided by the Ministry of the Environment (MOE), a classified list including local species in the area was presented in which the five groups were categorized by their preferences for low-temperature zone or high-temperature zone environments. This classified list was applied to the fish distribution data for six rivers flowing into Hakata Bay. It is noted that local species were found in all of the survey sites, while the indicator species specified by the MOE were absent in some sites. This suggests that considering local species as indicator species would provide more information on the conditions of the rivers.

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 1,4-dioxane is a toxic chemical substance which means to be difficult to take on-site soil investigation, compared with VOCs, because it has not been elucidated scientifically on geo-environmental behaviors. This study focuses on the partitioning and the distribution of 1,4-dioxane in soil, water and gas phases for inorganic soil and organic soils. The equilibrium concentrations in soil interlarded by 1,4-dioxane have been obtained under various conditions (pH, moisture content and water retention). The results showed that the distribution ratio of 1,4-dioxane to soil was 0.1 ~ 5.0%. However, under alkaline condition (pH 13), 1,4-dioxane could be distributed in the soil by an amount as much as 20%. The phrase soil water retention ability, 1,4-dioxane concentration largely changed due to the dilution of pore water in the soil with low organic content. Thus, it can be concluded that the majority of released 1,4-dioxane into the environment migrates to pore water in soil structure or into groundwater, unless it changed to a distinctive environmental conditions of high alkali and/or low water retention.

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 Flotation technique is very useful for removing residual contaminated particles in the sand fraction. Chemical scrubbing in a scrubber unit detaches contaminated particles from the surface of soil/sand particles. In a flotation unit, contaminated particles are selectively made hydrophobic by modifying their surface properties with selective flotation reagents. The hydrophobic particles are attached to air bubbles and are carried to the froth layer. The contaminated particles are scraped away with the froth layer.
 The objective of this experimental study was to understand the performance and validity of soil washing system which consisted of mainly hydrocyclone and flotation processing. A variety of soils contaminated with mercury, agrichemicals (BHC and DDT), dioxins, mineral oil, and radiocesium (radio-Cs) were examined. A surface-adsorption model and dimensionless load curves of feed soils were introduced and used in analyzing characteristics of contaminant distributions in soils.
 Removal ratios of hydrocyclone fluctuated greatly with contaminant distributions in feed soils. Flotation made up for the low ratios of hydrocyclone, and was able truly to improve the total ratios at high levels. The average removal ratio of hydrocyclone was 68.8%, and the average ratio was greatly improved to more than 90%, when flotation technique was employed for further treatment of hydrocyclone underflow (UF). A figure showing a relation between a recovery ratio to froth and a froth-to-UF ratio enabled us to provide a very effective way to visually grasp the flotation performance. The froth-to-UF ratios ranged at relatively high levels of 25~41 times, and the recovery ratios to froth remained at low levels below 5% for soils contaminated with dioxins, agrichemicals, and mercury. It is concluded that the flotation can work very effectively to remove contaminated particles that remain in the hydrocyclone underflow especially for above contaminated soils.

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 This paper discusses the economic impacts of climate change, including those on ecosystems. Using the dynamic integrated climate economy (DICE) model, we developed a new model (CEEM) to calculate the optimal path by considering new backstop technologies, such as CO₂ capture and storage (CCS). We identify the effects of parameter changes based on the resulting differences in CO₂ leakage and sites to analyze the feasibility of new backstop technologies. In addition, we focus on ocean acidification and consider the impact on economic activity. As a result, we find that new backstop technologies can only delay the effects of climate change, but its use is necessary to achieve strict targets, such as a 1.5°C limit.

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 The objective of this study to determine the latent factors influencing people to lead their pro-environmental personal norm. The subjects consist of 141 residents living in the upstream area of Cimanuk River, Indonesia. We used the data collected from a questionnaire survey. The data was verified to fit with our model which hypothesized “pro-environmental personal norm” attitudes towards “ascription of responsibility”, “awareness of consequences” and “new ecological paradigm” in relation to the Value-Belief-Norm theory made by Stern. Our results suggested that a causal chain of “awareness of consequences” and “intellectual desire for environmental education”. In conclusion, we formulated our model of pro-environmental personal norm as influenced by factors that the relationship between “ascription of responsibility”, “intellectual desire for environmental education” and “awareness of consequences”.

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 Nitrate contamination of groundwater has been recognized as an important public health issue. In this study, hydroxypropylcellulose (HPC) gel was used as an external electron donor in the in-situ biological denitrification process. In the continuous experiments using the bench-scale model aquifer, total nitrogen (TN) concentration in the groundwater was decreased along the flow direction. Although the denitirification efficiency in the model aquifer was low at around 15%, the problems such as clogging of the sand stratum and generation of nasty smell gas were not recognized through the experiment. From the results of the gene analysis, it was considered that the decrease in TN concentration in the model aquifer was due to reduction of nitrate to molecular nitrogen by denitrifying bacteria. These results showed that HPC gel could be utilized as the external electron donor in the in-situ denitrification.

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