The effects of the luminous color and luminance of LED (Light Emitting Diode) lighting on the larvae of firefly, Luciola cruciata and Luciola lateralis were studied in the laboratory. Preference tests were conducted using five colors of LED ray, namely white, blue, green, yellow and red. Negative phototactic response by both species of larvae was detected to white, blue and green LED of 0.1 lx or more. The larvae of L. cruciata avoided the yellow LED of 30-40 lx or more. While, the larvae of L. lateralis avoided the yellow LED of 5 lx or more. Larvae of L. cruciata and L. lateralis avoided the red LED of 60 lx or more and 40 lx or more, respectively. The present studies showed that the lighings of the street and car inhibit the behavior of the larvae of firefly.

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This study is aimed at estimating shear stress caused by rising bubbly flow working on submerged flat-sheet-type membrane surface using CFD method in MBRs. Shear stress was calculated using CFD code (ANSYS CFX11.0) and was also directly measured using a shear force sensor. Comparison of measured shear stress values with calculated ones revealed that measured time-averaged shear stress values were almost 1.8 times larger than calculated mean shear stress values due to smaller water-phase upward velocity near the wall than observed velocity which was measured by Laser Doppler Velocimeter. A simple method was developed to modify the simulation model changing the gravitational force term in the momentum transfer equation. The modification successfully made both of the calculated and measured shear stress values in good agreement. Standard deviation values of time-series shear stress data were calculated considering a momentum transport equation inside the viscous sub-layer and turbulent energy just outside the sub-layer. The calculated standard deviation values were larger than measured ones probably due to problems of sensitivity of the sensor caused of rather large area of the sensing part of the shear force sensor. The proposed CFD method was found to be an effective tool for estimating time-averaged and temporal fluctuation of shear stress on submerged flat-sheet membrane surface in MBRs.

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The characteristics of fine particles such as grain size and mineral composition contained into the sediment in three dam reservoirs (Dokawa, Matsuo and Kawaharu dams) along river Omaru in Miyazaki were investigated. The size of particles, which were difficult to settle as the cause factor of the turbid dam water for a long period, were average 2μm, and the shape was plane. By examining from the particles composition, the origin of fine particles in Matsuo and Kawaharu dams was identical with the fine particles in sediment of Dokawa dam. The content of fine particles was 10 mg/g-dry sediment and the settling velocity was markedly low (2 mm/hr). It was indicated that the clarification of suspension water in the dam reseroir containing the large amount of fine particles would be difficult by gravity sedimentation.

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Domestic tradable permits are one of the policies for reducing water pollution in closed sea areas. In this paper, a Computable General Equilibrium model is proposed for evaluating the economic impacts of introducing domestic tradable permits for water pollution control. The model-parameters are estimated using the Ise-Bay region as the study area, and the economic impacts of introducing domestic tradable permits for water pollution control in the Bay are shown numerically. The results of this analysis clarify the following points: 1) in the case of introducing tradable water pollution rights to only the mining and manufacturing industries, water pollution in the Yokkaichi and Gifu regions will be decreased and regions in Aichi prefecture will purchase the tradable permits; 2) in the case of adding agriculture to the tradable permits, water pollution in regions in Gifu prefecture and the Toyohashi and Ise regions will decrease, and the Nagoya, Toyota and Yokkaichi regions will purchase the tradable permits; and 3) in the case of adding agriculture, the economic impacts will be smaller than introducing tradable permits to only the mining and manufacture industries.

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We investigated effects of water flow paths on relationships between dissolved organic carbon (DOC) concentration and discharge, i.e., C-Q relationships in a headwater stream and discussed the estimation approach for DOC concentration. We found a strong positive C-Q relationship when the saturated overland flow (SOF) generated from the bottom of hillslope was the dominant flow path. On the other hand, we also found a weak positive C-Q relationship when the saturated subsurface flow (SSF) derived from the upslope area was the dominant flow path, but the slope of regression line was much smaller than that of SOF-dominated period (4%). The shift of dominant flow path from the SOF to SSF during a same storm event resulted in lower stream DOC concentration than expected value based on the regression line of the SOF dominated-period. In conclusion, we interpreted that occurrence of SSF had a dilution effect for stream DOC concentration. Moreover, we pointed out that analysis of flow path-based C-Q relationships can be helpful to estimation of stream DOC concentration.

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Scenario planning, in which multiple future scenarios are described to prepare for an uncertain future, has become more active. In this paper, we established several different scenarios on resource / waste flows and resource recycling / waste management systems in the near future (10−20 years) in Japan. 1) We identified “international markets and trade scheme,” “resource prices,” and “technology” as driving forces that have important and uncertain impacts in the near future. 2) Based on these we established four future scenarios: “international circulation of recyclables,” “international competition for resources,” “high-tech regional material cycles,” and “organized regional material cycles.”

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Satisfaction level for solid waste management was evaluated in Sapporo and Suita, Japan, by questionnaire survey method. Citizens were selected by three ways: random sampling based on Basic Resident Register and Internet monitors, and selection of Environmental NPOs. Internet survey shows uncertain bias, but NPO survey could be used to monitor the effect of solid waste management policies.
Questionnaires were designed to cover all aspects of waste management services, but satisfaction levels vary among a group of question related to one aspect such as collection of waste. To find groups of correlated questions, Cluster Analysis and Factor Analysis were conducted. The both methods formed almost identical groups, and the resulted grouping were almost the same between two cities. By using the satisfaction groups, which could be used as benchmarking index for solid waste management, the influence of citizens attributes and waste management service level were discussed.

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A large amount of carbon is accumulated in wooden house. To prevent the carbon dioxide discharge from urban buildings, the integrated building material circulation system to co-ordinate environmentally efficient recycle technologies and appropriate social circulation policy programs are needed. In this paper, the effects of environmental improvement by applying the integrated circulation system for the wooden construction material are evaluated.
Firstly, the recycling technologies of high-value added engineered wood and energy recovery were investigated. Secondly, to attempt an appropriate integrated circulation system in the wooden houses, integrated policy scenarios were designed to combine recycling technologies in the life cycle of the wooden houses. Thirdly, about each integrated policy scenario the effect of eco-efficiency from lumbering stage, transportation stage, operation stage, dismantlement stage, recycling stage, and landfill stage was evaluated.

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