The purpose of this analysis is to show the relation between household characteristics and the amount of domestic refuse generated, using data collected from questionnaires and waste generation surveys from households in the Tokyo wards over a 3 year period.
First, we analyzed what factors relating to household characteristics (i. e. occupation, number of occupants, type of residence) affect the waste amount by employing quantification theory type-1 and found that there was a close relationship between the number of occupants and their waste amount. Secondly, we classified the data into five groups according to the number of occupants, and carried out a statistical test to find their waste amount per capita. For single occupancy households, a strong correlation was found between the awareness of waste reduction and waste amount.
Also, focusing on single occupancy households, we conducted a comparative analysis between a group of single occupancy households generating much waste and a group of single occupancy households generating less waste and it was revealed that the daytime lifestyle (absent or at home) is a major factor affecting the amount of domestic refuse.

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As global environment problems are getting serious, green power promotion schemes have been carried out in many countries. This paper provides the information about what class of consumers would purchase green power, and what would gives them motivation to contribute by analyzing Japanese consumers' stated preference data collected through the questionnaire. Main findings from the analysis demonstrate that green pricing program would attracts many consumers among these schemes and they would be willing to pay for it higher than the others if the operating body which decide the application of the fund or issue certificates that the power come from renewable energy are managed competently.

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Preference of goods in household controls consumption of goods, and consequently influences supply and demand equilibrium of the country goods market. Also and more important, it determines the quantity and quality of households wastes. In order to project future waste amount generated by households, the abovemechanism must be taken into account. In this study, we developed a model of household waste generation based on Becker's household production approach. The model can consider the impact of lifestyle change on household generation. Also, it was applied to forecast Japanese household waste generation in near future.

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In order to evaluate “ability to pay” and “willingness to pay” to drinking water for low-income residents in Kathmandu, Nepal, we have conducted a field survey, mainly consisted of interview to the residents. As a result, we conclude that (1) there is big difference between the have and the have-not of the piped water in regard of economic and health burden, therefore urgent counteraction is needed, (2) there is distribution in household income even in low-income settlements, and relatively rich group has higher income than average household income in whole Kathmandu, (2) residents, even the poor, show willingness to pay for water, namely beneficiary to pay principle is adaptable even to the poor, (3) incremental tariff structure will be crucial for controlling water demand.

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In recent years globalization has proceeded, and there is growing concern about Carbon-Leakage problem. In this paper we have calculated the index of embodied CO₂ emission intensity among Japan, U. S. A. and Asian countries, which was derived from the I-0 table originally, and also factors of its change were examined. As a result, it was found that Asian countries had heavily induced the CO₂ emission loads on Japan, U. S. A. and China, and major factor of the change for the worse of it was sudden increase of the trade with foreign countries. In particular, increase of the trade with China seems to cause several countries worse off about it.

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This study aims to indicate the possibility of environmental economic valuation by the travel cost method which can measure only the use value, from the viewpoint of correlation between each value of environmental resources; use value, option value, bequest value, vicarious value and existence value. Andit shows the percentage of environmental economic value that can be explained by its use value. The resultindicates that, firstly, there are significant correlations between each value of environmental resources, so the value is not independent of each other. Secondly, the use value can explain 80. 17% of option value, 57. 79% of bequest value, 76.60% of vicarious value, 36. 71% of existence value and 78.98% of total value, so it is shown that the considerable part of environmental economic value can be explained by its use value and be measured by the travel cost method.

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The influence of winds and topography changes on the salinity environment in Yoshino River mouth was examined. As results of field observations, it was confirmed that the winds in the northwest greatly contributed to the recovery of salinity. The variation of salinity at the bottom layer was small both in summer and in winter was also clarified. As results of the numerical simulations, it was clarified that the topography changes at the river mouth influenced on the process of salinity recovering. In particular, the river-mouth bar greatly affects the salinity environment around Yoshino River mouth.

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We investigated the relationship between the population densities of aquatic animals and environmental characteristics of abandoned ponds in Aina, Kobe-City, Hyogo Prefecture. The main results are as follows:
(1) The most abundant aquatic animal in this area is crayfish. Populations of crayfish in irrigation ponds are larger during winter compared to summer.
(2) As the surface area of each irrigation pond decreases, the ratio of the crayfish per square meter increases.
(3) The geographical range of crayfish in these irrigation ponds shows characteristics of the naturalization process.

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In this paper, a new method by the regression tree model for the quantitative habitat evaluation is proposed. We compared the regression tree model with Suitability Index (SI) models of the Habitat Evaluation Procedure (HEP) or that of the Physical Habitat Simulation Model (PHABSIM). For our comparison, we used habitat characteristics of fish spawning beds in floodplain pools. Our results indicated that the error of regression tree model was smaller than that of SI models, and suggested that the regression tree method can be used for the habitat suitability calculation method of the HEP or the PHABSIM.

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Natural riverbanks are now disappearing rapidly because of river improvement and urbanization. In this study, we invetigated the features of natural riverbanks through field surveys and examined a method to measure the strength, for conservation and restoration of natural riverbanks. As a result that we surveyed the distribution of natural riverbanks using aerial photos, natural riverbanks has decreased remarkably in Kanagawa prefecture. And through field surveys, we understood the features of natural riverbanks, such as shapes, materials, vegetations and so on. Furthermore we estimated the riverbank erosion rate in Sakaigawa river and found that the riverbank erosion rate is slow and the channel has almost not changed since the Meiji period.

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This paper describes how the NDVI-based evapotranspiration estimation changes as the spatial resolution of the remote sensing image becomes coarser, and estimates the past or future evapotranspiration using land use data. With the 20-m SPOT/HRV image, the simulated images are produced using the degradation algorithm on the MTF. The images have resolutions of 30, 50, 80, 250, 700, 1100 and 2000m. The authors investigate the effect of the spatial resolution on the estimated evapotranspiration using these images, and show that the mean of estimated evapotranspiration does not change remarkably as the spatial resolution become coarser. This paper also proposes the F-C-U diagram to estimate regional evapotranspiration using the land use data. The F-C-U diagram can estimate easily the future or past evapotranspiration using the future or past land use data. The authors estimate the evapotranspiration change from the 1900s to the 1985s using the F-C-U diagram and LUIS (Land Use information System), which is the 2-km grid digital land use data set.

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An analysis of vegetation in urban area by using precedent satellite image has been inadequate in terms of accuracy. Recently many researchers have started conducting IKONOS, high-resolution satellite image. Firstly, this study compares the accuracy of LANDSAT data with IKONOS data concerned about vegetation measurement. Second, from the IKONOS data, we propose an index which could explain spatial vegetation patterns over the surface of urban area and show the validity in comparable analysis of Nagoya City and Saga City. Finally, we analyze the relationships between vegetation spatial patterns with land use pattern of Nagoya, in 10m grid's detailed digital information.

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We showed the effect of habitat isolation on rescue data of raccoon dogs, Nyctereutes procyonoides viverinus, in suburban area. We analyzed the factors associated with the rescue data from the relationship between the distribution of rescue points and the landscape patterns using GIS. We found that the populations in areas scoring the high isolation index (0.4 to 0.8), 10⁵ m² to 10⁶m² areas of forest landscape, and the low proportion (<0.4) of grassland landscape were suffered from high numbers of rescue data. The area proportion of the isolation index in forest landscapes which did not exceeded 0.4 were 0.10; the area proportion of the averaged area of forest landscape that exceeded 10⁶ m² were 0.51 and the area proportion of grassland landscape around the forest landscape exceeded 0.4 were 0.34 in the Kanagawa Prefecture.

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In this study, first we present the framework of the land use impact assessment method which is designed as a component of the life-cycle impact assessment system of endpoint damage approach in the National LCA project in Japan. Ecosystem is selected as safeguard subject by land use in this method. The output indicator of the endpoint damage in this study is loss of net primary productivity (NPP) of vegetations. Then, in order to make this method operational, we show the result of calculation of the damage factors by NPP. The factors are based on the calculated actual and potential NPP distribution by using vegetation and land use map, and climatic data, etc. in Japan.

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Natural open-spaces are amenities for residents in daily life and these are spaces decreasing damage in case of earthquake disaster. This paper shows that making process of alternatives for earthquake disaster mitigation by environmental creation. The region is regard as hierarchy relation of districts and chou-chou-moku in this process. Adjacency relation of districts and chou-chou-moku are represented by graph. These are nodes in these graphs. These nodes have information of factors about hazard of earthquake disaster. These graph expresses bias of earthquake risk in region. Alternatives for earthquake disaster mitigation by environmental creation are made using these information and graphs. Finally, analyses were done and making alternatives in Hokusetsu region.

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The aim of this study is to evaluate the bicycle compatibility of narrow back streets, which can be alternative routes for arterial roads like bypassed old type high streets. Bicycle users' sense and physical conditions, on cycling such as speed, vibration, conflicts with other road users, and air quality were compared between back streets, narrow streets, carriageway, and sidewalks. Back streets have better reputation than sidewalks shared with pedestrians, but have problems on the safety at junctions and conflicts with vehicles when it is narrow.

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Conventional estimation methods of environmental load from vehicle traffic generally use macroscopic emission factors explained by average travel speed. However, it cannot analyze the microscopic effects by traffic flow improvement on bottleneck mitigation or signal control. The study aims to estimate the amount of environmental load due to various microscopic traffic conditions using acceleration indicator, which strongly affects emission level. It is shown that estimated result of the reduction effect of environ mental load by microscopic estimation is greater than that of the macroscopic one when the frequency of ‘stop-and-go’ is reduced due to traffic mitigation.

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Developing countries in Asia have attached increasing importance to the development of urban environmental infrastructure (UEI), primarily in sewerage treatment and garbage disposal facilities, to overcome serious water pollution and solid waste pollution in urban areas. Funding difficulties are recognized as a barrier to accelerating UEI construction in this area, as large-scale initial investments are required. This paper argues that the expansion of possible roles for private finance initiatives (PFI) in UEI construction and operation is an important strategy for sustainable development in Asia to overcome governmental limitation in financing UEI.
This paper presents the situation of PFI projects development in Asia and identifies the principle of PPP and the risks of PFI project, as well as designs the framework for promoting PFI including to establish special governmental organizations, make appropriate measures to avoid risks and provide preferential policies for administration and financial support, and develop a manual for the formation of PFI projects.

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This research aims at explaining environment evaluation structure from the comfortableness and the protection disasters. The research to examine “The effect of the comfortableness” after the 1980's has been done abundantly. However, by this research, it is caught as a space, which it can make use of the river space for the time of the disaster as well, two space functions of “the comfortable space” and “the disaster prevention space” considered what kind of structure to be evaluated with it was aware. As for the utility of the synthetic space, it became clearer that it was strongly more aware of the protection against disasters from this research than comfortableness.

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In the paper, we built the Spatial Computable General Equilibrium (SCGE) model which is based on Geographic Information Systems (GIS), makes one mesh one region and incorporates the established physical evaluation model of water environment to economic evaluate the improvement measures of the water environment in the continuous point in a river. It confirmed that this model is able to apply as an economic evaluation method by calculating the cost and benefit and analyzing the impact on the social economy system caused by a water environment improvement measure in Yoshida River which is branch river of Nagara River.

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Viewpoints of several stakeholders were introduced to the concept of eco-efficiency in order to use it for incorporating the evaluation criteria of outsider into decision-making of the company, and to help dialog between factory and outsiders over the company policy. Value and environmental impact differ among stakeholders. Eco-efficiency of several air-conditioners sold in Japan was evaluated and compared for different stakeholders. Market share weighted with external evaluation of environmental soundness, market share, surplus value, and surplus value weighted with environmentally friendly design were value for company, investor, ordinary consumer, and green consumer, respectively. Eco-efficiency for various stakeholders was calculated for dialog on management strategies of a factory. Profit, tax revenue and job opportunity, and contribution to society were value for company and investor, neighborhood citizens and local government, and NGO, respectively. Environmental impact of the concerned aspects was calculated for each stakeholder. These case studies demonstrated the feasibility of such applications of eco-efficiency.

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This is a research for historical changes of the relation of common reeds and people around Lake Biwa in Shiga prefecture, based on documents and hearings.In this prefecture, common reeds had been more related to peoples life. But, today lakeside developments and life style changes have made them out of people's concern. They have been paid less attention in their life. Recently, as environmental value of common reeds, such as a water quality purifying function, have been focused on, Administration and some local residents perform common reeds preservation action, that is, reaping common reeds and making them torch to use in their torchfestival event.
In this research, referring to opinions of the ecologists who have special knowledge ofcommon reeds, and of the common reeds producer and processor, and clarifying importantpoints of maintenance and management of common reeds, tried is to propose a way of the futurecitizen participation type event of a common reed reaping and torch festival.

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This study investigates an impact of suitability regarding “Procedural Participation” on the Philippines ETA system upon attitude of affected people by project's implementation under conflict, and chooses the “San-Roque Multipurpose Project” as a case study for collecting data of people's perception. The statistical analyze uses “Covariance Structure Analysis” because of verification of the hypothetical model.
The result indices:(1) unsuitable implementation of the Procedural Participation makes a negative impact upon attitude of population;(2) Mass-Media makes impact upon attitude of population more than Procedural Participation because of the unsuitable implementation; and (3) public interest of project is essential as a factor of attitude of population.

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It is no doubt that forming the coalition among many agents is necessary to resolve the environmental problems. To encourage the formation of coalition, coalition formation mechanism should be studied. In many environmental problems, the interaction between state of the environment and the coalition behavior by agents is critical nature. However, this nature is not described in previous works. In this paper, the model to describe the coalition formation with such an interaction is developed by use of stochastic game. Then how the payoff structure affects the coalition formation is studied

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Social conflict between people insisting on environment and people insisting on development comes to be seen frequently. Especially, this tendency is conspicuous in the water resources development whose circle of influence is generally widespread. Management of such conflict between them must be considered on a future development project in order to avoid intensification and prolongation of useless conflict. In this paper, a mathematical model is built up to analyze such conflict and to see what kind of equilibrium states could occur. The model mainly consists of two parts. One is about changing process of strategy, which interest persons would choose. Another is the model about preference of interest persons, which is needed to set a pay-off matrix in the first part of the model. Furthermore, the model is applied to Nagara River Problem as a case study.

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In case a water resources development results in a bad influence on basin environment in Japan in recent years, the decision-making based on the consensus building between related stakeholders has become important. However, developments are sometimes planned on condition the characteristics of the area, public opinion, etc. have not fully been taken into consideration. We recognize the process to the result is more importanthan the result itself in the decision-making of a water resources development, so that a systematic process for performing the decision-making is proposed and is applied to the Yoshino River movable floodgate problem in this paper. First, the group promoting development and the group protecting environment are set up as stakeholders, and those utility functions are built. In addition, using group utility function considering convex dependence, we describe the decision-making when self-assertion becomes weak and compromise progresses.

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In recent years, the framework of public involvement has been requested in most public works. In river and coastal management works, acts and laws were revised. In these works, specialists function as interpreter of science, technology, decision-making system and situation of affairs. However, in Japan, the positioning and roles of specialists are not stable. Methods are discussed in order to solve these problems.

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In order to solve the global environmental problems and to create a sustainable society, it is necessary to establish the environmental science as an interdisciplinary science. One of the indices of the institutionalization of the environmental science is the environment-related departments in universities. Because the discipline of environmental science has not been well established yet, there is a gap between ideals and realities about research and education in these departments. One of the factors that caused the gap is the way these departments were established. The purpose of this paper is to scrutinize the mechanism of the establishment of environment-related departments, focusing on departments related to Construction (e. g. the department of civil engineering, the department of architecture, etc.). As a result, the higher education policy as well as efforts of establishment of the environmental science turns out to be one of the most important factors to the establishment mechanism of environment-related departments.

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To reduce the drought risk, it is promising measure to transfer the water from those who have sufficient surplus water to the water users who lack water. However, it is not used very much in Japan because it may not encourage the users to transfer due to no economical merit and so on. In this paper, water transfer contract is designed in order to give the water users the incentives to do so. In addition, we develop the model to guide the users to contract rationally so as to minimize the total expected discounted cost. We show that the water transfer system can be effective to reduce drought risk.

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An administration organ in wide area like a prefecture government provides part of drinking water to small cities that they have their own water sources like ground water for drinking. The merit and demerit of such a surface water usage in wide area were discussed and the benefit and risk were evaluated As a process, (1) the benefit from the project were classified every benefit subject, (2) all of benefit were quantified as the money term every items, (3) the influence of policies for water usage every items and every subjects by 72 cases of scenarios simulation were calculated, (4) and the alternatives of policies were evaluated by a principal component analysis. As a result, it was cleared that the optimum policy for this area is to receive all of the planned water volume from the prefecture government and deliver to all of areas in the Uji City

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Sustaining water supply requires appropriate improvement and renewals in actual pipe network system. In case of selecting a target pipe to improve or renew from enormous pipes and finding an effective additional route, it is desirable to examine all possible cases. Although hydraulic pipe network analysis gives information about hydraulic illness of the system under the given condition, it dose not support enumerating all possible cases of condition. Therefore systematic enumeration approach using simple and easy way substituting for hydraulic evaluation is required.
This paper assumes that water supply performance is strongly described by connection structure of pipe network, and discusses new index that shows water supply stability of network system. Assumption is verified by correlation with hydraulic index. Methodology for seeking pipe to be improved is shown through explicit enumeration process.

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In this paper, to regard a water circulation system as a network, a concept of water circulation sphere that consists of river basin, water supply area and sewage treatment area is proposed. The method of a network modeling of water circulation system in the sphere is shown. By applying graph theory, structural stability indexes, which imply the connectivity and redundancy of the network, to evaluate the network model are proposed. This methodology is applied to the case, which a waterway uses reclaimed water is introduced for waterfront recreation in great urban area.

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Photovoltaic (PV) cells are considered as one of countermeasures for saving electricity generated by fossil fuels. When PV cells are largely introduced in Tokyo, the surface heat valance will be changed. We developed a new PV cell surface heat balance model so as to assess all the impacts of introduction of photovoltaic cells, like a change of energy consumption resulting from a change of air temperature and a change of cooling loads in buildings resulting from the shielding effect ofphotovoltaic cells.
We set PV cells on the top of the roof of a research institute building in Tsukuba, Japan, and measured PV cell surface heat valance and meteorological data. From these measured data, we determined our model's parameters.

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The surface temperature measurement and the soil temperature measurement and the heat flux measurement were done in order to be quantified the effect of the heat absorption of the building by the roof top plantings. The strong correlation was observed between the differences of temperature of a slab vertical side and the heat flux. When the heat flux for four years were averaged about the period in July and August of a summer, at the vegetation section, the heat flux decreased by 7.3% of that at the non-vegetation section at the upward maximum. When the heat flux for four years were averaged about the period in January and February of a winter, at the vegetation section, the heat flux decreased by 59.0% of that at the non-vegetation section at the downward maximum.

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This paper discusses vegetation effects and sea breezes on the surface air temperature in the Tokyo metropolitan area using remotely sensed and regional meteorological routine data. Series of NOAA AVHRR images and seasonal meteorological data have revealed the interaction between land surface and atmosphere by sea breezes due to effects of energy advection from cool sea surface and high temperature in urbanized areas of Tokyo, detecting modification of the horizontal distribution of surface temperature in the Metropolitan area. The relation between NDVI obtainedby AVHRR and air temperature observed by AMeDAS extracted mitigation effects of about 5°C by vegetation transpiration on the Metropolitan air temperature.

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This paper estimates and analyzes CO₂ emissions from energy use in Tokyo and Seoul and analyzes performance of cities in East Asia, measured by CO₂ emissions per capita and CO₂ emissions per unit gross regional product (GRP). The contributions of selected driving factors for total and sectoral CO₂ emissions are also investigated by factor decomposition method. The results suggest that the performance of Tokyo is outstanding in comparison to major Japanese large cities, Seoul, Beijing, Shanghai, major OECD and major non-OECD countries. Income effect was primarily found responsible for majority of CO₂ emissions in Tokyo and Seoul in high growth period, i. e. 1970-90 for Tokyo and 1990-97 for Seoul. Despite economic recession, continued CO₂ emissions in Tokyo in 1990-98 is largely attributed to energy intensity effect. Similarly, the contributions of fuel quality effect, energy intensity effect, vehicle utilization effect, household income, labor productivity effect and scale effect etc. are analyzed for sectoral CO₂ emissions.

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A large amount of fossil fuel has been inputted into organic resource circulation system of city now. Moreover, about one fifth of supplied food is lost as food waste, and a large amount of fossil fuel has been consumed for treatment and disposal of the food waste. This study aims to develop a technique tool for political assessment of organic waste treatment and disposal, for this purpose, material flows from food production, consumption process to waste disposal process, currency cost, energy cost and packaging cost incidental to these processes in Fukuoka City are examined systematically. Method of material flow cost accounting originally developed for internal management of enterprise by German IMU (Management and Environmental Institute) andhinking of Life Cycle Assessment (LCA) are applied in this study. As a result, assessment frame for political assessment of organic waste disposal strategies was developed Material flows in Fukuoka City's food system from production process to waste disposal process, attendant energy cost and packaging cost in each process were calculated.

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A waste recycling network consists of collection, transportation, recycle and so on. But each process uses new energy or resource and the waste recycling is possible to bring about an increase of environmental load. In this study, to realize the waste recycling process to design a new society with low environmental load, 3 matters were investigated; 1) grasp of spatial distribution of waste discharge, 2) transportation between waste discharge site and recycling facility and 3) allocation of recycling facility in region that a energy consumption in waste transportation is minimized and treatment volume per recycling facility is appropriate.

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Using a computer model, studies were conducted on the regional solid waste management system, in which collected wastes of several member municipalities are transferred to a central treatment/disposal facility. First, the waste collection and transport activities, which are considered constraints for an extending service area, were scrutinized. Then, with a model made up of location, population, etc. of each member municipality, the cost and the energy consumption were calculated for a typical solid waste management scenario. Each scenario is composed of the activities such as incineration, landfill, composting RDF, etc. as principal treatment processes, and modified cases in which each municipality has a landfill were also included. Finally, the sensitivity analysis for location parameters was carried out.

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To deal with municipal waste problems, not only waste treatment but also change of life style and improvement of socio-system are necessary. In this study, from the viewpoint of material balance, a transfer function from goods to domestic waste is modeled. This model is composed of a goods purchase model and a waste release model. The former calculates amount of material input to the house from the purchased amount, and the latter calculates amount of waste at each composition based on material input. In this paper, consumer goods is defined as the goods that becomes waste within a year. Durable-goods is defined as the goods that is kept in houses over a year. Abandonment rate function is considered for durable goods when the durable-goods is abandoned. Container wrapping material is distinguished from the two goods, and the amount of that is estimated using Input-Output table.

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In this research, in order to grasp the present condition of the measure about the environmental consideration of accommodations for the accommodations in a Kyoto city, the questionnaire was performed. And the character of an environmental consideration was clearly classified into some types based on the grasped present condition. The system for evaluating the measure to the environmental consideration of accommodations in response to these results was proposed.

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We have investigated the actual conditions of separate collection of plastic packaging waste. And we carried out the questionnaire survey about the introduction of separate collection of plastic packaging waste for the separate collection of plastic packaging waste is enforced area and not enforced area. As the result the amount of foreign matter getting into the plastic packaging waste has increased from the beginning of introduction of the separate collection of plastic packaging waste. Factors of this foreign matter getting into plastic packaging waste are; 1) there are difficult products of the separate for the inhabitant, 2) there are problems which cannot be expected before the introduction of separate collection, 3) the inhabitant cannot seem to understand the effect by separate collection. Therefore, to reduce the foreign matters, we have to carry out the following actions; 1) Intensive promotion of information disclosure to the inhabitants, 2) Labeling all materials used for plastic packaging, 3) Establishment of management system about waste collection stations to the inhabitants.

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In Metro Manila, the National Capital Region of the Philippines, huge amount of organic waste deteriorates rivers and waterways. Under the present social and economic condition, however, it is quite difficult to build modem treatment farms as are common in developed countries. In this study, introduction of the composting-type toilets for treating both of human excreta and kitchen garbage at homes is proposed, based on field surveys about the present toilets and waste management in Metro Manila. Then, experimental results are shown on the weight reduction rate of organic waste when the both components are treated together in the toilet. In addition, the possibility for acceptance of composting-type toilets in the Philippines is discussed from the results of a survey by questionnaire at Ninoy Aquino Park where a composting-type toilet is installed.

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Effect of environmental flow in an urban river is estimated. Reclaimed water from sewage treatment plant is pumped up to its original intake (weir) and released to the river. The effect is described as changes in several hydraulic components such as water level and water surface width, and also change in water quality (BOD) is estimated. Flow duration curve is also utilized to quantify the flow re-regulation impact. Implementation cost for the project is calculated to compare the alternatives, and the cost-impact relationship is obtained.

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A large amount of sludge is discharged from sewage treatment plants, and therefore efficient sludge management system is needed to cope with the growing amount of sewage sludge. Energy efficiency in sludge treatment system is one of the important aspects so as to pursue the sustainable sludge management system.
Tokyo metropolitan government has been promoting recycling of sewage sludge as its sludge management policy. In order to evaluate the Tokyo's sludge management policy, we think it significant to analyze the aspects of energy consumption of the current sludge treatment processes such as dewatering and incineration, along with recycling plants.
In the Tokyo area, however, complicated sludge treatment systems have been historically applied, and it was difficult to comprehensively grasp sludge flow and energy consumption in sludge treatment systems.
In this study, we calculated the energy consumption and CO2 emission of each unitprocess in existing sludge treatment system and recycling plants in Tokyo, by looking into actual and detailed flow of sludge, which was clarified from primary data and hearing to Tokyo metropolitan government. We also conducted a comparative analysis of energy consumption between three sludge-recycling plants, and then examined current status of sludgetreatment and recycling system in terms of energy consumption.

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The cost effectiveness analysis is necessary for projects of social infrastructures. Methods to evaluate effectiveness of various projects in water works have been proposed. However, there are problems of double count of repercussion effect and omission of some effectiveness. In order to remove these problems, frame of benefit evaluation was theoretically examined from the point of general equiblium analysis and methods to evaluate project benefit were derived based on behaviors of consumer and producer. Case studies to apply proposed methods were carried out.

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In this study, we have developed an exhibition in order to effectively provide information on river environmental research and related knowledge developed at the Aqua Restoration Research Center to visitors. This exhibition was brought to completion in cooperation with the users that attended this survey. In the planning stage, we surveyed the interest of users on fluvial ecosystem. In the making stage, we evaluated the information layout of the panel using a prototype. Surveys were performed to collect the opinion of users on how much they understood the data and information presented in the panel. By the results of these surveys, we could pick out the necessary items for improving the panel. This research showed that exhibit evaluation is necessary to obtain a significant improvement in the quality of the exhibition and its displays.

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Varanasi, a holy place of Hindu, has a close relationship between the religion and water. The purpose of this study is to propose a method to reconstruct the relationship between the human and environment for the modern time based on the relationship between the symbolic riverbank space and its surrounding community through the Dev Diwali festival. Dev Diwali Festival is the largest festival in Varanasi today. The surrounding community called Mohalla is the center of this festival. In addition to traditional meanings of this festival, it includes a message to improve the current situation of Ganga since it has been severely polluted for the past ten years.
In this study, a hearing research was conducted to the residents in order to define the relationship between Ghat and Mohalla in daily life, and the influence of Dev Diwali Festival on the structure of Mohalla society was studied based on the hearing research and phenomenon observed during the festival. As the result, it was found that there is a structure called the traditional device and modern device that can be useful for the reconstruction of the relationship between the symbolic riverbank space and its surrounding community.

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Characteristics of microclimate in a greenhouse installed on the slope facing north were grasped experimentally, and verified by a mathematical model. On sunny days, a temperature difference of which maximum was 3 through 4°C was produced along the direction of sloping floor in the house, and the maximum of 2.5°C in temperature difference was produced in the direction perpendicular to the floor. On cloudy days, there were slight temperature differences in the both directions. These microclimates largely depended on the temperature difference between floor and film, which depended on solar intensity and house orientation. It was pointed out that the above temperature difference of 3 through 4°C is meaningful to the variation in growth rate of plants.

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The damselfly, Mortonagrion hirosei, was designated as an endangered species by the Environment Agency in 1991, because its habitat. is vulnerable to the effects of land reclamation and river improvement. Preand post-assessments of the habitat of the damselfly were taken at the site of the Tone Kamome Ohashi Bridge project spanning the Tonegawa River, which marks the border between Hasakimachi, Ibaraki Prefecture, and Choshi, Chiba Prefecture. Before the project, the larvae of the damselfly were found abundantly in the reed-covered area of this bridge on the Ibaraki side of the river in October 1998. However, there were no larvae found on this side after the project in December 2001. Also, the adults of the damselfly were not observed in July 2002. The larvae of the damselfly were collected only from the puddle of the depressed ground covered with dead leaves of reed plants. However, the puddles were filled with the alluvial deposits. The level of the habitats of the damselfly after the project was higher than before the project from 20 to 100 mm. Because the water supply from the watercourses and springs was decreased remarkably, the habitats of the damselfly were dried and the salinity of the habitats also became high. It was supported that the extinction of the damselfly on the Ibaraki side of the Tone Kamome Ohashi Bridge was caused by the reconstruction of the watercourse, which was extended and changed into boarded.

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