To develop the point-of-use water treatment by gravity-driven low-pressure membrane filtration in developing countries, we investigated the influence of membrane materials on fouling layer formation. We performed ultrafiltration experiments under the constant low-pressure using PES and PAN membranes. The resistance of fouling layers on PES membranes was one-third of that on PAN membranes. Application of the blocking model showed that cake filtration was predominant on PES membranes after second day, but the blocking model was not applicable to PAN membranes because the resistance of membrane was much higher than fouling resistance. CLSM observation and quantitative analysis of fouling layer structure showed that the fouling layer on the PES membranes had larger surface-to-volume ratio and porosity than those of the PAN membranes. These results suggested that it is preferable to utilize the high-flux membranes to mitigate membrane fouling in gravity-driven membrane filtration systems.

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 Individual behavior is more emphasis toward the realization of a sustainable society. It has become important to understand the relationship between the environmental improvement actions and the philosophy of values. In this study, discriminant analyses are used to to clarify the relationship between the environmental improvement actions and the emphasize level of each value (such as the environment, education et al.). Moreover, this study specially focus on the lifestyle with low environment load. The results show that values have a significant impact on the environmental improvement actions. People who emphasizes environment is likely to take different environmental improvement actions. People who do not emphasizes environment is also take actions by values when the value of electric and gas increase. People who emphasizes income and employment is likely to choose cost saving, while those who emphasizes society and living is likely to buy photovoltaic power generation facilities. This research revealed that analysis and encourage of values is effective in order to spread the environmental measures.

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 Payments for Ecosystem Services (PES), mainly designed for local farmer groups, have been practiced since 2011 in Japan. The main purpose of this PES is to compensate farmers' implementation of environmental-friendly agriculture. However, it is still problem that most of farmers do not participate the PES scheme despite of monetary incentive. The aims of this study are to test whether it has spatial autocorrelation and to reveal farmer's adoption factors using data from Shiga prefecture, Japan. Therefore spatial econometric approaches are applied. Results indicate that (1) positive spatial autocorrelation is important factors to join the PES for farmers, (2) some geographical position including the distance from Biwako-lake has an influence on farmers' adoption and (3) some conditions of farmer groups (e.g. diversity in age, large farmer ratio and social capital) has a crucial role in participating PES. These results suggest that targeting in incentivize strategies, formation of social capital, and increasing the number of large farmer can contribute significantly to motivate farmer group to participate PES. Incentivizing scheme in PES should be more flexible and tailor-made one.

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 Antibiotics are used worldwide for treating livestock. Because a part of the antibiotics administered to livestock is excreted as feces and urine, the antibiotics in the excrement used as compost may adversely affect agricultural soils and the surrounding environment. In this study, the sorption kinetics and the degradation of the macrolide antibiotic tylosin were investigated in the following three types of soils to clarify the behavior of antibiotics in soils: andosol, brown forest soil, and gray lowland soil. Microbial degradation of tylosin occurred in andosol and brown forest soil, which contain a relatively large amount of organic matter. In gray lowland soil, the residual ratio of tylosin was remarkably low under any temperature conditions, suggesting that the high degradability of tylosin is due to a physicochemical reaction with clay minerals in the soil.

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 In order to clarify the influence of shotcrete in the underground facility on the groundwater chemistry, an in-situ closed test of the mock-up tunnel was conducted at the depth of 500 m in granite. Portlandite, ettringite, gibbsite, K₂CO₃, natron, amorphous silica, calcite and brucite / nesquehonite were identified as the dominant minerals affecting the water chemistry. Furthermore, the shotcrete constructed in the tunnel has a reaction capacity which can produce about 570 m³ of alkaline groundwater (pH 12.4) saturated with Ca(OH)₂. The estimation would improve the accuracy of prediction analysis of the long-term chemical influence of cement materials after the tunnel closure.

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 An overpass for wildlife was constructed in Obihiro-Hiroo highway to resolve the habitat fragmentation. We monitored mammal species using the overpass with camera traps from May to November 2017. Recorded species and frequency in adjacent forests and the overpass did not differ. Therefore, we considered that mammals inhabiting in the local area recognized and used the overpass. The sika deer and the red fox frequently and continuously used the overpass. In particular, the sika deer used not residential individuals but also individuals of seasonal migration. Our results showed that the overpass is effective for middle and large mammals.

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