This study intends to make the following research;(1) firstly to examine the present conditions in wooded areas where maintenance works of woodland have been long neglected in the wake of local timber market shrinkage due to the increase of imported timber volume, (2) secondly to estimate the due impacts over environmental conditions in the downstream areas including urban areas, (3) thirdly to figure-out and propose the national land-management policy to systematize resources-recycling in a river basin based on the financial linkage between urban areas and wooded areas.

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A comparative study is performed for environmental problems in developing countries. Examples of environmental problems are collected, classified and discussed in relation to the stages of economic development in these countries. Time history of occurrences of these engineering problems is compared with socioeconomic development stage of each country. It is found out that environmental problems are closely related with industrialization and development stages. The developing countries in Asian region including ASEAN nations are accomplishing economic development well for the long terms before the recession period starting in 1997. Industry, agriculture, and the resort development were rapidly advanced. As a result, Asian region faces a rapid change of environmental system as having not experienced by the human race before. Also in African countries, for examples in Tanzania, we can observe the same type of environmental problems.

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For the preservation of the environment of soil and groundwater, recovery of contaminated soil and groundwater is required as well as prevention of contamination with chemicals such as heavy metal and volatile organic compounds. The researchers from Nagoya Univ. and seven private firms have worked together in the soil contamination workshop consisting of four subcommittees and have studied on the various problems related to the soil contamination for the past 2 years. Among these subcommittees, the first subcommittee has discussed the fundamental approach to the soil contamination, and the second has studied the survey and analysis methods of soil contamination. The third subcommittee has studied the preventing technologies and system of soil contamination and the fourth has examined relations between real estate transactions and soil contamination.

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As a means of transportation to connect the world, in particular, as a means of international human exchange, the airplane and the airport are bearing indispensable roles. The Central Japan International Airport “Centrair”, to be opened as an important hub airport in February, 2005, is now under construction over the Ise Bay, off the coast of the city of Tokoname, Aichi Pref. In charge of construction of this airport, from the early stage of the basic design, via construction, to its employment stage, “Centrair” has considered and will consider its harmonization with surrounding environment by reducing various environmental loads. In this session, we will introduce new attempts, which we have taken so far, to realize it. We hope the following presentations will help further development of the new technology.

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At present, many Asian countries need a reliable carbon dioxide (CO₂) emission factor for transport sector. For instance, though motor vehicles are on the increase rapidly in China, the CO₂ emission factor is not published. The purpose of this study is to determine CO₂ emission factor and to calculate CO₂ emissions for urban transport in China. The method of this study is to analyze existing statistics material of transport and energy in China. The following results were obtained:(1) CO₂ emission factors of urban transport were bus 178g-c/km, trolleybus 181g-c/km, subway 535 g-c/km, tramcar 145g-c/km and taxi 85g-c/km.(2) Based on traffic volume, CO₂ emissions from urban transport were 1.27 Mt-c (1999) and 1.40Mt-c (2000).(3) CO₂ emissions from urban transport were a small minority composing only 1.2 %(1999 and 2000) of the whole transport sector.

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Reducing CO₂ emissions is one of the biggest environmental issues which is captivating international concern. CO₂ emissions from transportation sector are increasing in both developed and developing countries. In this research we focused on four countries in Asia such as Japan, China, India and Thailand which are thought to be on the various stage of economical development. We conduct long-term projection on CO₂ emissions from transportation sector for those four countries. For the first step, we estimate transportation demand for each country using passenger transportation demand model and freight transportation demand model. Passenger transportation demand model reflects time use constraint which is the limitation of time spends to transportation activity of one person in one day. Freight transportation demand model is a simple model which estimates future value using current trends. Second, we estimate the CO₂ emission using bottom-up type model. This model describes technology choice using linear programming method. As a result, we could conduct long-term projection on CO₂ emissions from transportation sector for each country in the different socio-economical situation.

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The immerging need for preventing the world from air pollutions and global warming due to transport requires a group of researchers who have constructed an unlimited trust between members and a high expertise in the field of transport and the environment. WCTRS World Conference on Transport Research Society has provided an invaluable source for this. The CUTE project, which is a part of SIG (Special Interest Group) of WCTRS, has produced the first book to have described systematically from the causing source of the problems through good practices from 21 cities of the world, till political movements to be taken.

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The necessity of EST (Environmentally Sustainable Transport) has been widely recognized and yet, various measures have been implemented for EST. This paper aims to propose a new framework in order to measure the effects of transport systems on sustainability of cities. Motorization, as is the dominant factor of increase in carbon dioxide emission from transport sector, has the characteristics of irreversibility and synergism with urban sprawl. To deal with such issues, five topics are introduced: 1) induced traffic due to road improvement, 2) relationship between vehicle-related taxation and road budget, 3) relationship between public transport improvement and motorization, 4) impact of urban planning and land use management, and 5) public consensus for enforcing policy measures for EST. Finally, the paper draws attention to the necessity of benchmarking based on the given five topics for inter-city comparison and relative evaluation.

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In Tokyo Metropolitan area, large amount of construction waste is generated in recent trends and accumulated as various forms of construction. In order to promote a recycle of the aforementioned constrction wastes, it is required to build and study the reverse logistics model.
In this study, thus, two and unique models are being proposed:(1) Establishment of the central coordinating function to promote resources recycling and its development of public policy scheme.
(2) Debelopment of Supply-Chain-Managed infrastructures re-organizing existing recycle pinats.

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A thermophilic methane fermentation system of garbage combined with fuel cell power generation was constructed and has been in operation I Kobe to demonstrate its performance in reducing the greenhouse gases. Evaluation of environmental, economic aspects as well as the project outline and the operation results are discussed.
As a result, we proved that the garbage can be used for fuel cell, and this system is effective for reduction of the greenhouse gases

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This research takes as an object discarded PET bottles and glass bottles. First, the bottles are subdivided. PEI flakes are heated and melted, glass is mixed, and test pieces are produced. Next, unconfined compression strength and bending strength of the pieces are obtained. The production method of the tile which is not crystalized white and can be used as construction materials was examined. Furthermore, hardness was examined as one of the intensity measurements. The following conclusions were drawn:(1) Maximum of unconfined compression strength is 8.784N/mm².(2) Maximum of bending strength is 4.672N/mm².(3) The piece particle diameter of glass should be 2.00-9.00mm.(4) A mold is maintained at the same temperature as the melted PET, should be made thin.(5) The thickness of a tile should be about 4-8mm.(6) This tile has the almost same hardness as boards made of vinyl chloride.
Consequently, the standard of the fundamental production method of the practical tile was obtained

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In this paper, the framework of evaluation like Life Cycle Assessment for charcoal made of organic solid waste is examined. The societies based in mass production, mass consumption, and mass disposal depend on fossil fuel and underground mineral resources. In such a society, most of ‘productive activities’ is not productive activities in the true sense, but waste disposal works from underground resources to land surface.
To break out dependency on subterranean resources, our societies have to go into the society that the material recycling only depends on environmentally-friendly sources of energy such a biomass and that abandons excessive input resources as soon as possible.
Charcoal made of thinned wood and organic waste is helpful for fixation of carbon caused by burning fossil fuel. Because, especially, charcoal made of thinned wood is similar to the composition of petroleum and stable very much. The multifunctional substance such a charcoal needs to make a carefully decision on scenarios and period for evaluation. It is important that the framework of charcoal made of thinned tree and organic waste needs to have the perspective of the energy resource to material cycling, carbon-ycle and the treatment organic waste.

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The third world forum was held in Japan and A G8 Action Plan about Water was made in a main country summit meeting last year. The water problem is considered to be an international problem and becomes the problem that must wrestle with all over the world led by the United Nations. The present authors have reported about the importance of natural water and soil environment through the results of investigations in Yakushima Island of World Natural Heritage, Mikurajima Island of Toukyo where a giant tree grew thick, Iriomote island of Okinawa with original nature and so on. As well as Yakushima Island, Sirakami Mountain of Akita and Aomori prefecture was also listed as a World Natural Heritage Site by UNESCO in December 1993. Sirakami Mountain is known for virgin forest of beech that grows there. The objective of this study is to examine the feature of natural water and soil environment in which the virgin forest of beech tree could grow up, and to look for the way we can do for the preservation of nature in the future. The various chemical microanalyses were mainly carried out on the many samples of natural water, snowfall and soil obtained neighborhood the buffer and core areas of Sirakami Mountain. Based on the results of many chemical measurements, the present authors discuss about the actual situation of natural environment in Sirakami Mountain.

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To evaluate the protection effect of the Three Gorges Dam Project (TGP) on the flood in the middle region of the Changjiang River basin, we applied the integrated watershed hydrological model using gauged daily precipitation data of 1998 when the second largest flood occurred in the basin in the last century. From the results simulated by applying the discharge volume controlled by each upper limitation value from 40, 000 m³/s to 60, 000 m³/s, we could not find the clear effect on the reduction of the water level during flood period not only in the Dongting Lake but also in the Changjiang mainstream in the cases that the upper limitation discharge value were over 50, 000 m³/s. In the case that the upper limitation value was 40, 000m³/s, although the flood protection effect was clearly exerted in both the mainstream and the lake, the simulated storage volume of TGP remarkably exceeded the total flood control volume (221.5×10⁸ m³) at the peak of inflow to TGP. These results suggested that TGP flood control ability does not efficiently work for the decrease of flood damage in the middle region of the Changjiang basin in case of the occurrence of 1998 type flood phenomena.

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During the last two decades, Yellow River Basin witnessed serious water resource shortage, which has become serious constraint on economic development and caused various negative impacts on ecological system. In this study, water resource supply and demand are analyzed for Xian City which is located at Wei River Valley, the tributary of Yellow River. Then the Water-Resource Forecast Model based on the socio-economic database assesses the annual agriculture, industry and domestic water demand scenarios from 2000 to 2050.

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The groundwater has a constant water temperature, an excellent water quality, and if the pumping facilities are set up, a large quantity of groundwater is pumped up easily from the main aquifer in all continents. About two billion people are using groundwater. If groundwater is pumped excessively, the lowering of groundwater level generates land subsidence and groundwater salinization. Moreover, extending area below sea level is the one of causes of increasing floods. In this research, the case of groundwater management in the world and the ideal way of integrated groundwater management for appropriate use of groundwater without problems such as land subsidence and groundwater salinization is studied. And the action of the Tokai Three-Prefecture Investigation Committee on Land Subsidence, which aimed integrated groundwater management, is introduced.

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The seawater pumped- storage pilot plant (maximum output 30MW) was recently completed in Okinawa Prefecture, Japan. The site is located in the northern part of Okinawa Main Island, where the rich environment still remains. Many valuable, even endangered species are also found on and nearby the plant site. However, the land is covered with thick layer of red soil making a serious impact on the coral reefs when discharged. The point of environmental conservation measures was, therefore, that both the protection of valuable species and the prevention of sediment yield of red soil should be taken into great account during the plant construction and after its completion as well.
As for the actual countermeasures, small plastic fences and trapezoid-shaped gutters were installed around the construction site so that small animals could not intrude into the site and could easily bail out when trapped in the gutters. Sediment yield was also effectively reduced throuh catch drains, weirs, and sedimentation ponds. Environmental monitoring was carried out over the construction period. The plant site was fully restored to the native condition after its completion.

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The interest of the environmental problem has been increased world widely, and it is required to reduce the environmental impact. It is also recommended that civil engineers should pay attention to not only lifecycle cost (LCC) but also lifecycle environmental impact (LCCO₂) of civil infrastructures. In this study, the LCCO2 of newly developed bridges, named the minimized girder, the rationalized box-girder and the rationalized truss bridge in Japan were calculated. The LCCO₂ of the conventional bridges, I-girder, box-girder and truss bridges were also calculated and compared with that of the newly developed bridges. It was found from the estimation that the newly developed types of the bridges have less total LCCO₂ than the corresponding conventional bridges. These reductions of whole LCCO₂ of the bridge are resulted from the maintenance stage of the bridge.

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This paper recommends the planting of indigenous tree species as a countermeasure against formation of lakefront barren areas that are prevalent in multipurpose dam schemes nationwide.
The limited water-level method adopted by multipurpose dams usually results in periodic inundations in lakefront areas during significant water-level changes, leading to harsh conditions for plant growth. However, vegetation maintenance is necessary to prevent erosion. Thus, it is recommended that specific tree species such as willows, characterized by inundation-proofconsistent growth cycle and early growth, be planted in lakefront barren areas. This countermeasure has potential to become popular if its effectiveness is verified, because it is environment-friendly and relatively cost-effective, as it employs an indigenous species of willow.
The above results proved that the proposed countermeasure is cost-effective and easily implemented.

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At present, the world population of developing countries is increasing rapidly and the resident space is approaching a disaster critical section. Therefore, the help from the both sides of the thing and person is indispensable for the scientific analysis of the natural disaster environment and the improvement of the social disaster environment in the developing country by the United Nations and the various help organization. The present study investigated the features of sustainable disaster environment and future prospects for adaptation policies on the four models such as the parallel, series, parallel-series and series-parallel models arising from Model Reference Adaptive Theory. When thinking of adaptation policies by these models, it is important to note that the actual disaster environment is to be become the effective circulation by the disaster environment criteria based on the disaster recognition of real disaster environment and the schematic representation of disaster crisis.

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There are many people in the world who cannot access to the safe drinking water and appropriate sanitation. To halve these populations is one of the common goals for the world. In Bauniabad, one of the urban poor settlements in Dhaka, Bangladesh, many aid agencies have been working to improve sanitation conditions. In recent years, biogas plants have been installed as sanitation and people have been sharing a part of installation cost. The purpose of this study is to clarify the background of how poor people came to prefer and to use the biogas plant system as sanitation and the effectiveness of the biogas plant through questionnaire to the local people, interview to the stakeholders, and water quality analysis. It was revealed that though still people showed the difficulties to share all the cost of installation of the biogas plant, with the combination of the education on public health, there is a possibility to accept the cost share when people could understand the benefit of the option to their health and life.

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In regards to water pollution problems in closed coastal zone or rivers, municipal wastewater have been a major target of the environmental measurement after some effective pollution control measurements in decades in developed countries. International corporation or agreement have been developed for international coastal area or rivers including Global Programme Action (GPA), Global International Waters Assessment (GIWA) and Regional Seas Programme lead by UNEP as countermeasures to marine pollution. Environmental accounting housekeeping books for municipal wastewater has been proposed as an effective water pollution reduction measurements in the life of ordinary people in Ebigawa River drainage area, urban river running into Sanbanze tidal zone, Tokyo Bay, in this symposium last year. After that, water pollutants load per capita running into the coastal area has been proposed as an indicator for quantitatively evaluate loads of municipal life onto coastal area. This indicator was applied to six international coastal and lakeside regions and comparative analysis with an economic indicator was conducted in this paper. Whereas BOD load per capita running into aquatic zone has its peak at GDP per capita of 4, 000 and phosphorus load 10, 000. Nitrogen load does not have clear peak for GDP per capita.

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The purpose of this study is to find the strategy to handle human excreta properly in rural areas of developing countries. In this study, 85 Ecological Sanitation (EcoSan) toilets, based on an improved version of the Vietnamese Double-Vautlt toilet were introducedin a minority hamlet of Vietnam, which was located at highlands. Using these toilets, feces and urine are collected separately. Urine is used as fertilizer after dilution. Feces are stored in the toilet for a certain period. It is then sanitized by ashes, which raise the pH and make it dry. The sanitized feces are used as fertilizer. After using the toilets about five months, some roofs were damaged by strong wind in highlands and then the design of the roof was modified. Approximately 90% of the people could use the toilet properly through the continuous household guidance although minority people needed much more effort to adopt the usage of the toilet than other ethnic people. Through this project, it was verified that the EcoSan toilet was effective to handle human excreta in the project site. The EcoSant oilet is suggested as a toilet to solve the problems derived from human excreta in rural areas of developing countries.

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This paper describes the system for assessing fluctuations in carbon balance due to the variation of forest management scenarios. As a case study, the annual amount of carbon stocked by forests in Japan was calculated.The result shows that forests in Japan will be able to absorb carbon between 10 and 12 MtC/year, near the upper limit allowed by Marrakesh agreements, during the Kyoto Protocol's first commitment period. In addition, it indicates that the carbon absorption capacity will decrease year-by-year, suggesting that it is necessary to actively promote logging and reforestation in forest management policy in order to maintain that capacity.

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The global geological land use/cover data is essential to analyze the global environmental problem. Cropland distribution data is one of the most important land use/cover data. Because the spatially distribution of cropland is closely related with global problems, such as food security, water stress, land degradation, material circulation. We present a method for characterizing cropland distribution which links with geographical data such as Global Land Cover Characteristics (GLCC), Global Forest Canopy Density (GFCD) and census statistics of cropland. We also validated the method by comparing with the Japan's land-use with high accuracy, and confirmed that the estimated distribution by our method has high consistency than GLCC.

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Biomass is expected to play an important role to solve global warming problem and energy resource depletion problem. In order to utilize the biomass, we need a reliable estimation of its volume. We developed a “Global Biomass Table” to evaluate comprehensively the biomass flow related to human activity. The global biomass table shows the biomass flow of input, output, export, import and waste at each economic sector in 1997. We used the economic data (GTAP Vr. 5) which divided the world into 66 regions and divided the each region into 60 sectors. As a result, we can overview global biomass flows. For example, the waste of biomass is produced 4.76 PgC in the world. The waste is equal to 20 % of exhaust carbon emitted from fossil fuel. China and USA and India produce much waste and approximately half of the waste is occupied with agricultural residue. USA and India export much biomass. On the other hand, Japan and Korea import much biomass which equal to two third of domestic biomass consumption.

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The authors compared Japanese forest plan with the case which they thought coordinate with sustainable forest management according to national, regional and management unit scale. These are Canada. the British Columbia province, McGregor Modelforest, FSC (Hayami Ringyo). The authors deliberated what the challenge of Japanese forest plan for sustainable forest management. The conclusions according to the scale are as follows: in national scale, commissioning the regions to decide the details of the plan. using the broad indicators and creating the organizations for consulting with forest industry sector and the publics; in regional scale, using perforamance targets, building partnership and socializing the private forests; in management unit scale, making the plan based on environment, society and economy and understanding and adopting FSC principles and criteria.

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Annual changes in the temperature/precipitation and a runoff process in the forest watershed were investigated from the statistical analysis of various time series records. The climate change has not appeared in only a temperature increase but also changes in the precipitation pattern such as the extension of nonprecipitation period, the shortening of precipitation duration and the cyclic interval of heavy rain, and so on. Such climate change become causes of the shortening of precipitation-runoff response, the decrease of the amount of effective precipitation, and the increase of the sediment yields through the increase of evapotranspitation and the decrease of the soil moisture.

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With progress of economic globalization, countries are strengthening interdependence of not only trade but environmental resources. While some countries are transferring their environmental loads to out of the region, other countries are achieving economic growth by producing goods and services that consume significant resources. We must not neglect the indirect use of environmental resources that are put into the production of goods and services imported form other countries. This paper quantifies interdependence of energy consumption and land use in Asia-Pacific region from 1985 to 1995. As a result, it is shown that the interdependence is formed centering in U.S. and China. Especially, China is taking over the responsibilities for energy consumption and land use.

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This paper is to analyze relation between the change of socio-economic conditions and process of environmental legislation in China during the recent five decades. It is recognized that the environmental legislation has been materialized in line with the planning of economic development in China. However, its future legislative execution would be questionable as far as the economic development is not completed yet. Herein, the authors intend to propose systematization of industrial pollution control in China, based on the analysis of Japan's previous experience to overcome the hazardous pollution caused by big industries.

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This study intends to satisfy the goal, which imposed on the environmental planning such as “The sustainable development”. From the standpoint of ecological planning, quantitative cognition of interrelationship between blessing of nature and favor of scientific technology and also demand of man is important for this goal. For this purpose, five parameters such as 1) Capacity of CO₂ fixation, 2) Capacity of cooling, 3) Capacity of space, 4) Capacity of water resource, 5) Capacity of wooden resource are assumed in this study, and the environmental capacity and mechanisms of fluctuations of environmental capacity of river basin as Eco-system on the three metropolitan areas in Japan are analyzed by using mathematical modeling and also Geographical Information System.

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China has been processing a tremendous economic growth in these two decades. Simultaneously, the extent of the environmental damage caused by industrial activities has also been expanding and it has become one of the matters of world concern. We constructed China multi-regional input-output tables for the environmental analysis in 1997 and employed them for inquiring the environmental load like SO₂ emission in a view of the regional relationships. The results of the study provided that the SO₂ emission in the eastern coastal region, which occupies the most of the emission in China, depended on their own final demands as well as the emission in theinner region did. We found important investigating the matters on China on a regional level.

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This paper focuses on the application of EST guideline system on integrated urban management policies for sustainable regional growth or environmentally sound urban regeneration. It is to present strategic visions and guidelines for the environmental management for Kawasaki City, Japan. by providing significant and practical recommendations and strategies for Kawasaki City. This paper contains the thllowing contents.
Firstly, planning system and driving schemes for Kawasaki Eco-town Project developments are provided. Relevant legal and financial systems of urban policies for Eco-town Projects are provided as well as project goals including the reduction of GHG for municipal urban programs are also provided. Secondly the research scheme to identify the function of Eco town project as a driving force for circular Kawasaki Metropolises is proposed. Extensive circular ties with neighboring factories; neighborhood metabolism or zero-emission districts, expansion on eco-efficient product chain management and core function for city-scale or waterfront zone circular economies are investigated.

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While sustainable region is a common pressing target for a municipality, Okayama Prefecture was adopted for its Eco-town project in 2004. This paper reports interdisciplinary research actions for the Eco-town, which contemplates identifying environmentally sound technologies for mainly wood wastes such as activated charcoals as well as developing them into utility products and establishing the integrated river basin management frameworks and decision support tools. Firstly, water environments of down-stream regions of Okayama Prefecture are identified as critical local environmental concerns. Secondly, activated charcoals are experimented, as focal innovative environmental technologies, for its absorbing and dissolving functions for organic contaminants. Finally, integrated environmental material flow assessment system is designed tentatively.

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The structure by which the outflow corruption to river which has brought about organic matter inflow to which population, processing of an organic matter superfluous in the river basin region area of the big city to which concentration of industry went, consumption, and abandonment exceed the environmental capacity in the river basin region area, and the corruption load of point and non-point in the ocean space carried out are finally discharged by the exclusive ocean space of a mouth of a river through a river has caused the present serious aggravation as a result.
In this paper, the generating distribution of the organic waste in a city region was calculated in Saitama Prefecture and the Arakawa river basin region area over Tokyo using the calculation system utilizing GIS. Evaluation results identify about the application possibility of small-scale biomass energy use among the circulation use systems of an organic matter on it.

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A new index was proposed to evaluate the environmental condition in the watershed. Since this index was defined as the statistical variance of the amount of mass flow in the runoff process, it included effects of the continuity on the mass flow/circulation system and the various human activities. As the results of the investigating the definition of the index, it was found that spatial scales of non-point source such as cultivated lands and the runoff length where the natural purification was fully exhibited became important to the environmental assessment.

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Western Java area has been numerically investigated using PSU-NCAR MM5. Mesoscale numerical simulation was performed under the synoptic scale meteorology by ECMWF data with a resolution of 0.5⁰ × 0.5⁰. Five days long simulation on 4-9 March 2001 was carried out. During this period, the quite strong sea breeze developed on 5 and 6 March. On March 6, 2001, at 1300 LST, the sea breeze penetrated to around 20 km from the coast of Jakarta. In this season, over Java area a synoptic scale convergence line is formed by WSW and NW winds. This synoptic WSW wind blowing over Java tends to prohibit inlandward advancement of the sea breeze. Depth of the sea breeze, on 6 Mar 2001 at 1200, 1300, 1400, and 1500 LST was 0.5, 0.8, 0.4, and 0.2 km, respectively; because of subsidence behind the convergence line by the synoptic WSW wind and the sea breeze from Java sea, upper part of the sea breeze layer was warmed after 1500 LST and thus the depth of the sea breeze was suppressed. Predicted near-surface wind at 4-9 March 2001 appears dominantly with westerly wind. In mountain area, wind direction was affected by a mountain wave. Highpressure system tends to be formed to the northeast of the Sunda street because of the topography. Then this highpressure system in turn generates dry stable layer over Jakarta at 2, 000-4, 000 m height and may suppress vertical diffusion of pollutants over Jakarta.

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Using PSU/NCAR mesoscale model MM5, we performed 1km-gridded wind simulation for the feasibility study of offshore wind power generation over Ise Bay. It is shown that the simulated wind speed have a bias of about ±11%, a root-mean-square error of about 40 to 50% and a correlation coefficient of about 0.7. As for the simulated wind direction, the bias is about 6 degrees and the root-mean-square error is about 40 to 50 degrees. The annual mean wind speed at 60 m height is found to be 5 to 7 m/s over most parts of Ise Bay. We consider a depth of 20 m as the maximum depth for an offshore wind power plant, and then the area with a depth of less than 20 m occupies about 62 % of the bay. If we arrange typical 2 MW wind turbines at every area of 10D×10D (D: diameter of a blade) or 10D×3D, total power generation is estimated as 6, 925 or 23, 085 GWh/yr, respectively. This means that offshore wind power potential over Ise Bay is equivalent to the power from a few nuclear power generators.

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A special material for pavement, “Katsuren Travertine” is produced from limestone (foraminifera rich) mined enough around Katsuren Town in the Okinawa Island. One advantage of “Katsuren Travertine” as a paving material comparing with others like concrete is saving the increase of surface temperature by solar radiation. To apply this “Katsuren Travertine” on pavement in urban area for thermal environmental mitigation, the saving mechanism has to be quantitatively evaluated. The authors have settled “Katsuren Travertine” with the size of 5m × 5m and comparative normal concrete blocks on a flat grassland with no sunshade, and monitored surface temperature, conductive heat flux, radiation balance, and other meteorological factors from July to November in 2003. As another comparative study, the high-albedo painting which fitted the reflection rate to “Katsuren Travertine” was applied on the surface of the concrete. Due to not only its high reflectance but also its thermal physical factors like specific heat capacity, the authors concluded “Katsuren Travertine” has a potential to mitigate urban thermal environment. But more examination is necessary about the physiological impact for pedestrians of the application.

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In recent years, disasters by abnormal rainfall was reported by every corner of the earth, and it has come out the necessity of estimating these disasters objectively. The purpose of this reseach is to show how global analysis should be done by proposing new indexes of the abnormal rainfall event. Furthermore, as a part of realization of the proposal, this research defined these indexes using rain gauges distributed over every corner of the earth, and performed global analysis of abnormal rainfall with these indexes.

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Asian sandstorm particles called “Kosa”, which are emitted from the desert area of China and transported to the north pacific countries, can affect the cloud droplet formation. Sorption of the atmospheric gaseous species on the sand surface during the transport makes a kind of composite CCN. In order to investigate the effect of sand particles embedded in the composite CCN on the equilibrium cloud droplet size, numerical simulations are done using the new mathematical model for competitive growth of cloud droplets. The new model has been constructed based on the physicochemical consideration. The numerical results with composite CCN composed of kernel water-insoluble sand (quartz) and its coat of soluble chemicals (ammonium sulfate) show that the larger the kernel sand size, the more the amount of vapor is condensed. That is, sand kernel of composite CCN makes the net droplet size (exclusive sand) larger.

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ABSTRACT; Europe has already established tentative critical levels of air pollutants based on the dose responses, however, not yet in the Asia. The critical levels are becoming needed for evaluating plant responses to air pollutants in the East Asia. Current ozone level has the potential adverse impact to plants. On the other hand, Forestry Agency in Japan carried out forest health monitoring survey. However, the relation with air pollutants is not clarified. This study analyzed observation data by using GIS to evaluate the relationship between air pollutants and decline, quantitatively and visually. Study areas are Sugi (Cryptomeria japonica D. Don) forests in the Kanto plains, where many surveys and reports have been done. Geostatistical analysis (kriging method) was applied for making oxidant based AOT40 (Ox) map in the forest monitoring period of Forestry Agency. The distribution and range of AOT40 (Ox) were compared with daytime and nighttime, and different monitoring period. Furthermore, AOT40 (0x) values were extracted and analyzed at each monitoring point, to examine the relationship between the mean decline index and climate normals (ATP, Precipitation index) or land use (e. g. forest rate).

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Aerosols optical models are necessary to retrieve aerosol distributions from satellite data and to estimate aerosol direct climate forcing, however, aerosol optical properties such as single scattering albedo (ω) and optical thickness are rare information over ocean. In this study, the aerosol optical and chemical properties were measured from 1999 to 2003 in the western Pacific Ocean on board the research vessel Mirai. We encountered mainly four air masses which included maritime air mass, air mass influenced by fossil fuel combustion, that influenced by biomass burning, and dust plume in these cruises. The values of ω ranged from 0.68 in biomass burning to 0.99 in marine air mass. The region between 30° N and 40° N, air mass was influenced by aerosols emitted from fossil fuel combustion both in the summer and winter cruises. Since absorptive aerosols were measured in the winter cruise, the mean value of ω in this region in the winter cruise was 0.74, while transparent aerosols were measured in the summer cruise (mean value of ω was 0.92). This seasonal difference mainly comes from a difference in the concentration of elemental carbon.

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A global scale chemical transport model for gaseous and aerosol species (AGCTM) has been developed to study possible effects of changes in human and natural emission activities on atmospheric environment and the Earth's environment. The AGCTM simulation as well as Lagrange particle simulation was performed for about 40 days from Feb. 21 to March 31, 2001 during TRACE-P field campaign. In the Lagrange particle simulation, emission areas for yellow sand and anthropogenic pollutant in China, Korea, Taiwan, and Japan were identified, and movements of the hypothetical non-buoyant particles released from the areas were kept tracked for one week. A technique to label particles with different colors for those released on different days allowed us to estimate spatial distribution of aged air-mass. In the AGCTM simulation, calculated results were compared with TRACE-P airborne observation, TOMS Aerosol Index, and surface observation in China.

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Numerical investigation of NOx removal by activated carbon fiber (ACF) set within porous fences was performed. The fences were installed at both upper and ground levels of double-decked road, and how much amount of the emitted NOx from the road can be removed by the ACF was evaluated. Obtained results showed:(1) NOx concentration, for example, at a height of 10m and 10m downstream from the road can be reduced up to by 50-60% by increasi porosity and the activity of ACF;(2) similarly, at the ground level, the reduction of NOx can be by 20-40%;(3) these highest performance was obtained at the porosity of 60% and the estimated highest activity of ACF with a rate constant 6.28 s-1 under the assumption of the first order chemical reaction.

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In Ryukyu islands, the outflow of reddish-soils from the areas of public utility, developments of farmland and resort, establishments of the U. S armed forces becomes a very important social problem. The contamination problem of reddish-soils has given serious damage to the sea environment, fishing industry, tourist industry and so on. In this report, the authors propose a new method to estimate the degree of contamination due to the reddish-soils and discuss on the actual situation of contamination in the sandy-seashores and the some beaches at ebb tide in Ryukyu islands.

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The excessive algal bloom and oxygen-depleted water which are frequently observed in Mikawa Bay, have led to the growing public concern. On many marine systems, nutrient has been identified as the pollutant of concern, and is believed to stimulate the excessive alga growth. This study investigated by numerical simulation which factors may regulate the production of chlorophyll-a in the bay. We, therefore, analyze the three years calculated results using statistical method to investigate the relationship between river flow, riverine total nitrogen (TN) inputs, water temperature, bay nutrient concentration and primary productivity. Both hydrodynamic and water quality variables were calculated using a dynamic model which includes hydrodynamic equations and 13 mass conservation equations for chlorophyll-a, dissolved oxygen, etc. The obtained result are as follows:(1) chlorophyll-a has the strongest correlation with TN, and temperature, and additionally with total phosphorus (TP), (2) the flow rate of fresh water from land area was one of the most important factors to regulate TN concentration in the bay.

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Rivers form deltas wherever they flow into standing water such as a lake, a reservoir or the ocean. Under conditions of constant base level of standing water deltas can be expected to gradually prograde outward, so that the delta shoreline regresses “seaward.” Rising base level can not only slow this progradation, but reverse it, so that the shoreline migrates landward, or transgresses. An extreme limit of this case is one of shoreline starvation, for which the supply of sediment at the shoreline drops to zero and the delta goes into transgressive autoretreat. A 1D morphodynamic model of delta response including backwater effect is developed to clarify the response of delta to sea level rise. The simulations revealed that the interaction between sediment supply and sea level rise determines whether or not a) the delta continues to prograde under conditions of sea level rise, or b) the delta begins to transgress and eventually goes into autoretreat.

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When a building and a forest are burned down by a fire, it generates a lot of gas of various kinds. Conventionally, in the area of research of a fire, the examination about the influence (toxicity) on which poisonous gas, such as carbon monoxide, carbon dioxide, hydrogen chloride, hydrogen cyanide, and two or more hydrocarbon, has the influence on the environment by fire combustion gas to a human body has been made. However, the air pollution by the gas which occurs from a fire can be said to have not thought at all about the environmental impact to global warming or ozone layer depletion from the first. So, in this research, in order to clarify relation between fire outbreak gas and global warming, it tried to perform prediction of the amount of generating of the gas which occurs from a fire, and impact evaluation to the earth environment by the simulation using the prediction result. Even when a building fire and a forests-and-fields fire were totaled from the result of analysis, it was shown that it is equal to about 120, 000-person CO₂ emissions per year. Moreover, the importance of presuming these values by Monte Carlo simulation was shown.

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Damages of typhoon-induced storm surges would become more severe. As level flooding model is used in the past prediction of the flooded areas of storm surges, the areas and population at risk tend to be overestimated. In the real situation, floods meet resistance of roughness on the land such as land forms, vegetations and buildings to form a slope of the penetrating water surface. In this study, storm surges and resultant floods over the land are estimated by long wave models to examine the effects of typhoon parameters, land form, and land roughness. The conditions examined are; typhoon parameters such as central pressure, propagation speed, and incident angle to the coast line; and land parameters such as slope and roughness. A systematic relationship is obtained between the flooding distance and the parameters. This result can be used to improve the accuracy of the flooded areas for the regional and global estimates.

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