We chronologically summarized Hokkaido's winter meteorological conditions and examined warming trends and climatic disturbance trends, based on meteorological records. It was found that temperatures in Hokkaido in recent years have been higher than the average of past years (1961-1970), and the increase in miriimum temperature has been greater than the increase in maximum temperature. Summary and categorization of meteorological charts on heavy rain and snowfall events in winter also confirmed a decrease in the number of such weather events that were caused by winter pressure patterns and an increase in such weather events caused by low pressure. Furthermore, a trial calculation of the degree of effect of increased temperature on runoff in this cold, snowy region indicated that runoff in seasons of snow cover (snow accumulation season and snow melting season) is more strongly influenced by increased temperature than is the runoff in summer.

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Global emissions of methane and nitrous oxide from agricultural sector account for approximately 85% of agricultural GHG emissions. It is necessary to determine the effectiveness of options reducing methane and nitrous oxide emissions. We estimated methane and nitous oxide emission reduction potentials in 21 regions of the world in the future, by considering options' reduction rate, the applicabilities to agricultural production systems, and the marginal abatement costs. We calculated the reduction potentials by regions and by GHG emission sources. As a result, global reduction potential in 2030 is estimated to be 350 MtCeq/yr, which is equivalent to 20.2% of the GHG emissions in the BaU case. The regions which have the highest reduction potentials are China and India. The reduction potentials of China and India account for 51.6% of the global reduction potential. Therefore, it is required that China and India play some important roles to reduce global agricultural GHG emissions. In addition, the proportion of the reduction potentials by sources varies with regions. Therefore, it is necessary to determine the most efficient options by regions and to introduce these options.

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Risk assessment of CO₂ leakage from geologic sequestration sites is unavoidable for the implementation of the technology. However, the nature of the risk is different from well-known other toxic materials due to the complexity and uncertainty of the earth crust structures, long life time of CO₂, and wide spatial distribution of leakage and its risk. In this paper, the characters of the risk and involved factors are summarized, and risk assessment schemes arediscussed. Impacts of the leakage, flow paths, mechanism, and categorization of the storage structures are essential to assess the risk. A quasi quantitative analysis method is also proposed.

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This study aims to develop an evaluation method of the impacts of climate change on Social Hazard, which represents the general vulnerability of urban systems. Various kinds of vulnerabilities are not only caused by the impacts of climate change, but also by various urban problems in an urban system, for example, the increase of automobile traffic, urban sprawling, and location in the disaster hazardous area. Social Hazard of a housing lot, the social life cycle cost per one Quality Of Life (QOL) unit, is defined as a comprehensive indicator for vulnerability caused by these urban problems. This study proposes the representation of Quality of Life, by using the Quality Adjusted Life Year, originally developed in the medical field. This evaluation method of the vulnerability of an urban system by Social Hazard Index is applied for the examination of adaptation and retreat measures against climate change.

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It is the most important issue for the sustainable society to reduce output as disposal and input of natural resource. This paper shows directions of how to reduce the output from public works and the input for public works.
The directions are how to select good ways from various type of recycling. The first is to check from view point of the output of society. The second is to check from view point of the input of society. According to the directions, we found some recycling ways cause increase of the input and/or the output.

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Recently, a lot of disasters by typhoon and earthquake have occurred. The processing and the disposal of a large amount of disaster wastes are important problems. In this study, we researched the situation of disaster wastes in The Mid Niigata Prefecture Earthquake in 2004 as an example, and examined the problems of processing/disposal of disaster wastes. As the results, it is shown that the peripheral environment is negatively affected by the disaster wastes. Considering the hygiene securing and environmental preservation, the local government should be planning various systems such as the support system of large area including peripheral local government and the prompt environmental countermeasure by the case of the prolongment of temporary depository. In particular, at the area where probability of earthquake outbreak is high, we need to have the plan that managed the disaster wastes, immediately. A problem of appropriate processing and disposal of the disaster wastes is common problem to the world, and it is considered that the world contribution for this problem is necessary into a field of vision in future.

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Waste incineration standards have been tightened recently as there has been a growing interest in the environmental issues such as dioxin disposal and illegal disposal of wastes. Above all how to dispose of discarded farming vinyl has become an urgent question.
By examining the strength through bending tests, this study discusses whether the solid body processed out of the vinyl can be used as interlocking blocks, a construction material. Moreover, Contribution to the bending strength was discussed with the mixture of a cord.
The conclusion is as follows;(1) The basic pattern was envisaged for the best condition of the amount of cement, the ratio of cement and water, and the amount of waste rock powder.(2) The strength can be increased by using Portland cement and waste rock powder, and samples stronger than the standard strength of interlocking block can be produced.(3) When the specimen that ware mixed cords was deformed, the large fracture strength was shown in the large deformation too.(4) The specimen that was mixed cords into 1 layer is better than that of 2 layers. The best quantity of cords mixed in 1 layer was 4 cords.

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Beijing's MSW (Municipal Solid Waste) amount has increased rapidly with the rapid economic development and population increase in recent years. However MSW treatment and disposal facilities are not enough due to different reasons such as financial deficit. Environmental pollution in the urban area, resulted from MSW that was not properly disposed, has become serious environmental and social problems. In this study, prediction for MSW generation and collection, and scenario analysis on demand of MSW treatment and disposal facilities in the future, were done as a preliminary discussion of improvement strategies for Beijing's MSW treatment and disposal. In particular, the multiple regression analysis model, which made the rate of urbanization (the non-farm population/the total population) and the rate of the tertiary industry GDP the explanatory variable, and made the MSW collection amount per person the Criterion Variable, had been built. And three scenarios are set under three different conditions respectively, i) all new facilities are landfills, ii) new facilities are incinerators mainly, iii) new facilities are built according to the Beijing's MSW strategies on disposal rates of landfill and incineration in 2020. MSW treatment and disposal facilities' requirement till 2020 are estimated by the three scenarios. In consideration of the intermediate treatment and the final disposal, the MSW disposal flow model including the amount of reclamation and recycling till 2020 are built by the three scenarios. Moreover, energy consumption and CO₂ emission by life cycle assessment (LCA) and cost assessment had been applied in the research.

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The purpose of this research is to find the condition of “the watershed management” as the means of the realization of the land preservation management by the cooperation between the city area and the farm village and the forest area. It aims at solving the environmental issues which are caused by the weakness of the relation between them. This paper reports the knowledge from the watershed management workshop in 2004, which was held to collect information sources of the research and the policy about the forest and the river management and the citizen's action which derives from “the eco-pride (ecological & economical pride)” to support their watershed environment and community soundly. There are three points of view on this research and workshop, 1) to evaluate the public interest feature of the environment of the forest and the agriculture about the water circulation and the carbon fixation. 2) to evaluate the contribution which is called the utilization of the forest resources by the economic activity for the private interests, 3) to grope of the mechanism to relate the public interests and private interests (public-private relations).

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This research is aimed to calculate the amount of the generation pollution loadand the amount of the flowing pollution load in the Kojima lake region in Okayama prefecture where the pollution load is accumulated and the problem of eutrophication is elevated. By using GIS tool, the region is devidedinto several catchments and the spatial distribution is analyzed to investigate for the situation of the pollution load. The regression analysis is used to examine which sector of the generation pollution load influences the flowing pollution load. As the result, the industry sector is found to be the most critical factor for TOC loading, wheares T-N loading is mainly influenced by agriculture sector, and T-P loading is greatly effected by household sector.

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The soil erosion at farmland becomes serious impact on the ecosystem in the coral reef in Okinawa district. In order to solve these problems, it is necessary to build a support system for the integration of the measures in a river basin. This paper examines the approach of watershed management for thesupport system as follows, 1) the role and the collaboration in various stakeholder, 2) the requirements of building watershed management, 3) the image of watershed management in Ishigaki island, and 4) the fund system for environmental preservation.

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In this study, the end is to solve the problem of red clay outflow and of coral reef extinction caused by its in Ishigaki. We extracted the consideration to environmental problem and the order for measure by joining the group, other university and administrative organ. And using listening investigation to inhabitants, administrative organ, sightseer, private enterprise and NGO, we examined the more effective measure from academic point of view. In 2004, with this field survey, we got two outcomes. One is getting hold of awareness each other to the problem of red clay outflow in Ishigaki. The other is that we were able to have the chance inhabitants have awareness of these issues. In this paper, we showed the result of listening investigation and questionnaire survey and proposed the more effective step.

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Pollutant loads per capita flowing into public water bodies and environmental accounting housekeeping (EAH) books of domestic wastewater were proposed as an index and a tool for dissemination and environmental education. This paper summarized the index in two drainage areas, Ebigawa River drainage area and the inner city rivers in Chiba City. The indexes were 0.3-5.2 g-COD person^-1 day^-1, 2.5-4.3 g-N person^-1 day^-1, and 0.22-0.43 g-P person^-1 day^-1, in the Ebigawa River drainage area, and 0.83-21 g-BOD person^-1 day^-1, and 1.2-13 g-COD person^-1 day^-1 in Chiba City. The effectiveness of the original EAH books, those of CO₂, has been considered as not enough. However, researchers should indicate some quantitative and scientific information for the resolution of environmental problems. Actual and effective application of the index and the tool would be possible in the scenes of water pollution problems in developed countries including Japan, and domestic wastewater treatment management in developing countries.

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Qibainong is one of the groups of hamlets which are located in the north of Guanxi Province, China, where karst topography spread out. Qibainong consists of about 700 hamlets. One hamlet forms a closed society where tens to hundreds of people live by themselves, at the bottom of a doling formed by a karts phenomenon. Environment of karts area is deteriorated in 1958 by the economical advance period when many forests were cut down. The authors started researching water quality since 1999, aiming at getting water safe for living in quality and quantity under the condition of unstable water cycle of Nongshitun, one of Qibainong in krast area. We found out that the clean water spring contains much alkaline earth metals and carbonates. And while it flows through field, it is contaminated by fertilizer and agricultural waste that makes concentration of nutrients increase. And we found out that in rainy season, those valuable nutrients flow out from the outlet of the doline. From the results, we proposed to use the lucid spring water for drinking, and to build a pond near the outlet of the doline to make nutrients to circulate.

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The Karimantan in Indonesia has rich tropical forest and wetland, but recently it has been changed by forest fire and haphazard land development. It is the subject to understand the condition of these wetlands and find the appropriate way to develop them while protecting the natural environment.
The purpose of this study is to research the influence of human activities on the natural wetlands' water environment by determining the water quality in the Central Karimantan region. In the wetland, the water quality is an essential determining factor of environmental change, and it is strongly related to agriculture, drinking supply and ecosystem.
In this study, the three researched areas are along the Sebangau river. The water in each of these areas has specific characteristics which will be compared. The result shows that the natural area has a stable water condition through rainy and dry season, which means that the area has a high ability of buffering. On the other hand, the area which has the influence of human activities has the high concentration of phosphorus and inorganic nutrients. Also, the character of water outflow shows it has a lower ability of buffering.

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Land-use change around Sarobetsu Mire for agricultural purposes was started as an antidote project against food shortage after World War II. During 1961-1969, a short-cut channel was built to prevent the floods by lowering the water level. This led to the invasion by an exotic species of dwarf bamboo, Sasa kurilensis that prefer dry conditions in place of the native Sphagnum spp. The reduction in water levels were further affecting the water chemistry, creating ombrotrophic-minerotrophic gradient from east toward the western area. This study assessed the long-term changes in the composition of vegetation which accompanied by the changes in water chemistry regimes. Using canonical correspondence analysis (CCA), it was found that beside hydrological parameters, the succession of vegetation in this degraded bog was closely related to the nutrient contents and surface waters' mineral contents. The results also highlight the influence of hydrologic parameters on water chemistry regime; they control the chemical as well as biotic processes in mire ecosystems.

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The estimation of the contribution of long-range transport of the pollutants from East Asia to the urban pollution in Japan was performed by using the chemical transport model. Fine model domain which can resolve the urban emission area was nested within the coarse model domain which covers whole East Asia where the amount of emission is increasing rapidly with an economic growth. We investigated the seasonal variationof the contribution of long-range transport on the tropospheric ozone concentration during January to June, 2004 by comparing the calculation which includes all emissions over East Asia and the calculation with no emission except Japan. As a result, the contribution of the long-range transport on the clean region is larger than that on the urban pollutedregion. Average contribution on the ozone concentration was 5-8 ppb on the ground. This is 20-30% of the average background ozone concentration, and 10% of the environmental standard (60ppb). Especially, from March to May, contribution is large and there is a risk of increasing the damage to an ecosystem. If the NO_x, emission in the Asian continent doubles by further economic development, the contribution of the long-range transport will become more severe.

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In order to characterize optical properties of atmospheric aerosols in East Asia, the absorption coefficient (σ_ap) and the scattering coefficient (σ_sp) were monitored at three islands (Fukue Island, Miyako Island and Amami-ohshima Island) in East China Sea from 2002 through 2004. The optical properties ?Dap and ?Dsp at these islands showed high values in winter to spring and low values in summer. The single scattering albedo at Fukue Island ranged from 0.7 to 0.9. Further, aerosol measurement campaigns were performed in springs among the period. During the campaign besides the measurement of optical parameters, aerosol particles were collected on filters to determine chemical component concentrations. Using the chemical concentrations, σ_ap and σ_sp were calculated by Mie scattering theory for assumed mixing conditions and particle size distributions in aerosol model. The calculation use twenty kinds of particle size distributions and three mixing conditions as parameters. The best correlation with observed values were obtained in the geometric mean radius of 0.075?Em, the geometric standard deviation of 1.3 and external mixing condition.

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Effect of aerosol particles on global warming, i. e. mainly cooling and, in certain situations, warming, is considered roughly in two aspects of “direct” and “indirect” influence on radiation balance in the atmosphere. Because of not simple relationships among nature of aerosol particle, such as size, chemical composition, etc., cloud microphysics, and atmospheric dynamical field, “correct” quantitative evaluation of the “indirect” effect is, in particular, difficult, and its result tends to have large uncertainty. To reduce this uncertainty partially, we are developing AGCTM (Aerosol Global scale Chemical Transport Model) which can explicitly describe source-receptor relations on various chemical species forming aerosol particles. By using the model, we have performed numerical simulation of transport/chemistry/deposition of aerosols and other chemical species during 20 Feb to 31 Mar in 2001 on the occasion of TRACE-P campaign. Performance of our AGCTM has been evaluated mainly by comparing the calculation results with TSP (Total Suspended Particulates) concentration at various observation sites all over China.

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The obtained spatial distributions of NO₂ and SO₂ show that the highest concentration appears near the high traffic main highway, and then higher concentrations in business center and industrial areas. The highest “oneday” NO₂, appeared at a site near toll highway in central Jakarta, was 446.1μg/m³; 16 observation points including this site exceeded 92.5μg/m³, the Jakarta ambient air quality standard (Jakarta AAQS). On the other hand, “one day” SO2 concentrations were below the Jakarta AAQS 260μ/m³, though these at two sites were over the WHO AAQS 125μg/m³. Vertical profile, up to 110 m high, of air pollution was also studied using a high building in business center of Jakarta. The “one day” NO₂ concentration were 119.8, 101.3, 87.6, and 100.4μg/m³ at 10, 30, 55, and 110 m high, respectively, and similarly those for SO2 were 7.3, 1.8, 6.5, and 16.2μg/m³. It is interesting that the SO² increases with height, suggesting huge point sources of power plants located along the coast in the north-eastern part of Jakarta may be resulted in this profile under the sea breeze condition. At the symposium, the results will be discussed together with CTM calculation.

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Observation of air temperatures was conducted simultaneously in urban and sub-urban areas in Tokyo for the validation of a one-dimensional urban canopy model. The observation results showed that the distribution of daytime temperature was inhomogeneous due to the presence of insolation, while temperature at nighttime was not remarkably different among the measurement points. Averaged temperature in sub-urban area tends to be higher than that of urban area during daytime. However, at nighttime, temperature in urban area was about 1 degree higher. This suggests that, during our measurement period, typical heat island phenomenon occurred. Using these observed results, we evaluated numerical model performance. The performance was largely affected by solar radiation used in the model, that is, calculated daytime temperature was under estimated as solar radiation was obtained from GPV of JMA-RSM. On the other hand, the performance was fairly improved using solar radiation obtained form sunshine percentage data provided by AMeDAS sites.

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Nocturnal mountain breeze appears in Nagano City and it invades to central part of the urbanized area. In meteorological conditions which mountain breeze appears, urban heat island would also appear and thermal mitigation of urban heat island by mountain breeze as a relative cooler air flow is expected. In this study, features of the mountain breeze in Nagano is clarified by meteorological observations and its thermal mitigation probability on urban heat island, namely, an availability as urban ventilation lanes is discussed.

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Recently, it is shown that the climate change will make the rainfall situation change. A weather and rainfall forecasting needs the past weather records and experiences to analyze. For that reason, the usual forecasting way has to adapt such rainfall situation changes. This study will show a new countermeasure of the rainfall/flood forecasting method to the climate change.

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Recently, Information Technology (IT) has spread quickly in Japan. In this study, we developed a model to estimate the influence of IT on industrial economy and to estimate the related environmental load. This model consists of two modules, input-output analysis module and energy conversion module. The former module estimates multiplied effects of adoption of IT on industry economy, and the latter module calculates CO₂ emission by using the relationship between the emission and industrial production. An IT spreading scenario including evolution of broadband network, electronic commerce (BtoB and BtoC), and telework was considered. As a result of our estimation, demand for power sector increased, and CO₂ emitted from oil products decreased due to reduction of transportation. Total CO₂ emission increased because of large amounts of demands for the power sector.

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The purpose of this paper it to detect discontinuous permafrost in the subarctic taiga of Interior Alaska by using geophysical prospecting. Alaskan taiga is characterised by permafrost overlaid with an active layer. For shallow discontinuous permafrost mapping, we carriedout electorical resistivity sounding. The following results were obtained: beneath north-facing slopes, there is a continuous high electorical resistivity zone, the under boundary of which is almost flat through summer, and the thickness of which is between 10 and 20m. It follows from this that the high resistivity zone is almost equivalent to permafrost zone. Beneath south-facing slopes, two high resistivity zones are near surface and underground cavities at the depth of about 15m. It follows from these that the high resistivity zones are not equivalent to permafrost zones, these phenomena of near surface appear to depend on being dried through summer and on cavities of scree. And the permafrost and whose active layer influence the biology of the taiga. The second goal of this study was to describe the temporal variation of vegetation. The north-facing slopes have Black spruce-mosses woodland. The south-facing slopes have Aspen-birch forest, whose foot have Sphagnum mosses mire. The watershed have Dwarf shrubs.

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Global warming and its accompanying sea level rise will be serious issues in the future. According to the Intergovernmental Panel on Climate Change (IPCC), a global average sea level rise of 9cm to 88cm is projected for 1990 to 2100 and a steady increase of sea level for all of the scenarios considered is expected. In the coast regions, coast disasters caused by storm surge coupled with sea level rise are likely increased. To examine adaptation strategies against the increased coastal hazards, it is important to understand the characteristics of storm surge events. The aims of this study are to determine the most dangerous typhoon conditions in the Suo sea, to compute the maximum storm surge height, and to estimate the possible inundated area and population by using the Geographic Information Systems (GIS).

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Since the influence methane affects global warming matches by about 20 times (warming coefficient) the carbon dioxide, we consider more the influence by the methane generated from a nature. Especially the point that the quantity of the methane generated from the organic matter accumulated in soil or underwater by warming increases must attract attention from a viewpoint of warming prevention. However, the present condition is that impact evaluation which the greenhouse gases which occur from a plant or a microbe system give to global warming is not fully carried out. In this research, while carbon dioxide and methane examined the mechanism discharged from a nature, the experiment concerning the anaerobic fermentation of the laboratory scale about the increase in the amount of generating of the carbon dioxide by an environmental rise in heat and methane was conducted. The environmental impact by the gas which occurs from a nature was quantified by performing the impact evaluation simulation exerted on global warming using this experimental result.

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Geo Power System is a natural air-conditioning system for residential and commercial premises, using geothermal energy available beneath the ground surface at a depth of 5 meters. Geothermal energy can be explained in simple terms as the thermal energy available at a depth of 5 meters below the ground where the temperature remains stable all round the year between 15-18 degrees Centigrade i. e. 59-65 degrees Fahrenheit. It is intelligently designed to ventilate the interiors to all corners and to effectively enhance the internal conditions by removal of formaldehyde which is harmful to ones health. This system provides natural environment-like conditions to oneself, increases house life and protects the environment.

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In Asia-Pacific Region, structure of energy consumption is changing. It is guessed that the factors are rapid economic growth in China, monetary crisis, globalization and so on. International Input/Output tables are used for clearing the factors which change the structure of energy consumption. In Asia-Pacific Region, Institute of Developing Economies estimates Asian international input/output tables every five years, but it has a problem that it needs long time until it is published. Now the latest version is 1995. Therefore it is difficult to clear the factors which change the structure of energy consumption after 1995. In this paper, first of all, a method for updating the Asian international input/output tables is proposed. Secondly, the Asian international input/output table in 2000 is estimated by using this updating method. Finally through the input/output analysis, it is cleared that the change of economic structure occurred the changes of energy consumption in this region.

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Purpose of this study is to analyze a role of exchange between urbanresident and fishing community for the eco-social system which is defined as coexisting system with human beings and environment in a region.
In this paper, as a case study on exchange between urban resident and fishing community, the activities of the fishermen are examined and analysis on the activities of the fishermen aiming at conservationand application of the fishery resources and sustainable fishery and fishing communities from viewpoint of regional eco-social system is conducted.
As a result, the subjects for developing eco-social system in the fishing communities so efficiently and functionally are restoration and conservation of natural environment, change of utilization method on substance resource in the coastal area and reform of social structure.
Exchange between urban resident and fishing community is contributing to not only financial substitution for catching fishery but also understanding on fishery and marine environment for the general public. Therefore, to develop exchange between urban resident and fishing community positively is expected that eco-social system would be functioning sufficiently.

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High economic growth that Japan had experienced and rapid urbanization have begun to advance in many cities in Asia. Bangkok in Thailand, there is a large difference in maintenances of urbanization and the infrastructure, and various problems are caused in convenience of citizens' life and urban environmental maintenance. Bangkok Metropolitan Administration (BMA) has required the help to JICA for the proposal to drain the flood water caused by urbanization through Japanese experience 20 years ago. This paper shows a result of actual research how the proposal had adjusted in Bangkok, and how the graduate students from Asian countries in AIT (Asian Institute of Technology) contributes Japanese experiences to the students to understand their role in future as a representative in their country and discover the global cooperate spirit through the study meeting with global view.

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Kyoto University has been carrying out the cooperative works with China in the field of environmental engineering through “JSPS-MOE Core University Program on Urban Environment” and “MEXT Program for Modem Needs of Higher Education.” In addition to these activities, Graduate School of Engineering, Kyoto University has planned and is preparing the establishment of the Research Center for Japan-China Environmental Engineering on Tsinghua University's Shenzhen Campus, China. The Center will be opened on October 1^st, 2005 to come up to the expectation of both administrative and industrial sectors in Japan and China.

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It is well known that quality of rainwater (e.g., acidity) is dependent on the chemical substances which originate from such scavenging processes in the atmosphere as rainout (in-cloud) by cloud droplets and washout (below-cloud) by rain drops. Rainout plays an important role in the acidification of rainwater, as the first stage of scavenging process. However, characteristics of rainout process have not been made clear yet both theoretically and experimentally, because the accurate field data on cloud droplet quality are quite scarce. In order to estimate the nonsteady acidification of cloud droplets and the contribution of rainout to acid rain formation, the cloud droplet acidification caused by absorption of SO₂ (g), H₂O₂ (g) and HNO₃ (g) is investigated numerically, using a mathematical model based on the physicochemical considerations. The cloud droplet acidification process are implemented by lumped differential equations. From the numerical results it is concluded that:(1) the dominant species for the acidification in the cloud droplets is changeable as HSO₃- in very early period, and then NO3- during next three hours, and thereafter SO₄^2-;(2) droplet-phase oxidation of HSO₃ plays an important role for droplet acidity, even in the case that strong acidifier of HNO₃ (g) coexists; and (3) even after one-day rainout most of SO₂ (g) remains in the air-phase, but most of HNO₃ (g) is consumed within one-minute rainout.

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In an attempt to identify the ionic imbalance, hydrogen carbonate, HCO₃^- (bicarbonate), was determined together with the commonly determined nine major ions because the imbalance was frequently encountered in the chemical analysis of samples with high pHs. Titration method was applied for the determination to the samples with pH higher than 5.6. These samples amounted to 102 of the 1, 536 samples collected in Hokkaido, Northern Japan, from April 1998 to December 2002. Of the 102 samples, 74 (Group A) showed an acceptable ion balance without including HCO₃^-. In the other 28 (Group B), however, inclusion of HCO₃^- successfully improved the ion balance. These results suggested that HCO₃^- was a potential candidate for explaining the imbalance. The hydrogen carbonate concentrations showed a strong correlation with the corresponding non-sea salt calcium (nss-Ca²⁺) concentrations, which implied that HCO₃^- was derived from calcium carbonate particles incorporated into falling raindrops or cloud droplets. For Group A, the relationship between HCO₃^- and the nss-Ca²⁺ concentration was very similar to that for commonly suspended particles in Hokkaido. On the other hand, Group B exhibited a stronger but significantly different correlation. To the samples of Group B, a back trajectory analysis was applied to demonstrate that the samples were associated with aerosol travelling from Northern China or Mongolia

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BTEX (benzene, toluene, ethylbenzene and xylene) hydrocarbons have a high toxicity and are major VOCs (Volatile organic compounds) in contaminated gas from the specific pollutant sources. Biological treatment of BTEX from contaminated gas containing has been considered more economical and environmental technique than the conventional physical or chemical treatments. In this study, the effectiveness of the direct aeration treatment system using specific BTEX-degrading bacteria was investigated. The o-xylene contaminated air was readily degraded through the aeration tank containing o-xylene-degrading bacteria (strain TKN14) in the laboratory scale. Whereas all of gaseous BTEX from gasoline-contaminated soil were degraded readily by the aeration tank feeding with effective microorganisms derived from the contaminated soil and strain TKN14, two weeks were needed to start the effective biodegradation of gaseous o-xylene when only contaminated soil were fed in the aeration tank at the beginning of the treatment. The direct aeration system has an ability to purify contaminated gas with the loading aromatic hydrocarbons of 20mg L^-1 h^-1. The results of feasibility study suggest that biological treatment using the direct aeration system is useful for removal of BTEX from contaminated gas.

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Mercury emission in Kanto region is estimated in this study. Fossil fuel consumption facilities, waste incinerator, lime manufacturing plant and ships are selected as mercury emission sources. Emission intensities of these facilities are evaluated. As a result the mercury emission from all sources in 2000 in Kanto region is 1.5t/y. Emissions by source categories are estimated as:
·power generator: 67kg/y
·waste incinerator: 697kg/y
·lime manufacturing plant: 44kg/y
·ship: 33kg/y
·coal consumption facility: 264kg/y,
·hazardous waste incinerator: 10kg/y,
·sewage plant: 413kg/y

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Changes in the amount and composition of tar according to superficial velocity (SV) were investigated in a downdraft biomass gasifier. SV of the downdraft gasification with air was varied in the range of 0.3-0.7m/s, and tar was recovered at the gasifier outlet. The tar was classified as gravimetric tar and gas-chromatography-detectable (GC-detectable) tar. The lowest gravimetric tar yield (0.7%) was obtained at 0.4m/s SV and the highest at 0.7m/s. GC-detectable tar yield was highest (1.5%) at 0.7m/s. One-ring aromatics and naphthalene accounted for more than 80% of GC-detectable tar mass. Some constituents of GC-detectable tar showed specific trends according to SV, although the main composition did not show extreme change. The effect of SV on the production of gases and particles was also studied.

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In this study we evaluated the carbon balance in a metabolism process of wooden building stock, such as “planting”, “the wood transportation”, “accumulation to a building”, and “incineration” As for the quantity of CO₂ absorption by planting, as for the CO₂ discharge about 22, 000t-CO₂, the wood transportation, it was estimated that some 140, 000t-CO₂ decrease, a CO₂ discharge by incineration were caused by large increase of disposal wood outbreak quantity, and 34, 000t-CO₂, the quantity of CO₂ stock to a carving wood building showed increase of 134, 000t-CO₂ between ten years from 1992. I increased, and it was estimated that they greeted a peak in about 2010, and, in 2007, as for the CO₂ discharge by incineration, 2.5 times were able to estimate imported lumber to be when they cut quantity of annual carbon release by 1.9% reduction by replacing it in domestic production materials.

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The attempt to restore forest after construction work has been conducted. In most case, the mixture of soil material and seeds was sprayed to cover naked land. Similar methods have been applied for the greenery on surface rock al-though sprayed soil was rapidly fell down several years after spraying. In this paper, greening methodology on the steep slope formed on the surface rock exposed to gather rock was studied. The reforestration of steep slope face (1:0.8) required the development of new greening technology including the selection of plant species, treatment of the surface of rock (formation of root-bed), introduction of seedlings instead of seeds of grasses. The field survey was also conducted to determine the soil mixture used for the spraying method. The field test with small scale was also conducted on site. These results indicated that inorganic materials (soil or sand) were more suitable than organic materials as soil materials. For the planting of seedlings (2-3 years old), it was necessary to prepare small cavities (root-bed) on the surface rock to support root elongation of seedlings. Three experimental plots (400 m² each) were selected with varied soil texture, weathering stage, spring water availability, and number of cracks. One year after plantation, the survival rates of seedlings were 46.6% on low weathered surface rock as compared to those of 71.3% and 76.6% of high weathered surface rock with exuding spring water, respectively. Based on these results, reforestration methods to create natural forestry were discussed.

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Toward improving riparian forest management, we studied blowndown caused by Typhoon Songda in 2004 in riparian forests along the Ishikari River. Two kinds of riparian forests grow along this river: those within the embankments (“bankside forests” of predominantly Salix), and those in channel cutoffs outside the embankments (“cutoff forests” of predominantly Ulmus davidiana and Fraxinus mandshurica). Whereas blowdown in bankside forests was severe, blowdown in cutoff forests was minor. In bankside forests there was little damage to immature trees, but extensive branch and trunk breakage to mature trees (age‹20 years, H/D* ratio›85) and extensive uprooting to overmature trees (age‹30 years, H/D ratio›65). In cutoff forests there was little typhoon blowdown -even of mature trees -because the trees there are tall and thick enough to resist strong winds. Trees in the cutoff forests range in age from 60 to 190 years, and the H/D ratio for the trees of those ages ranges from 25 to 75. In view of windfall damage control, logging is needed every 20 years to maintain the bankside forests. However, if those forests are replanted with species found in the cutoff forests, then the logging can be greatly reduced in frequency -or possibly eliminated. Such replanting will also improve the discharge capacity and biodiversity. It is desirable to replant bankside forests with cutoff forest species.*height-diameter

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In order to clarify the correlation of a climate change and a forest surface change of state, data analysis was conducted concerning the secular fluctuation tendency of temperature and rainfall runoff and SS. And the model applicable in a forest basin was built and the microscopic soil particle quantity of production from forest ground was predicted based on the global warming scenario.
Due to a pronounced increase in the number of days exceeding 25°C in the forest region, the quantity of soil moisture evaporation is increasing. As a result, the amount of soil moisture in the forest ground surface layer is decreasing. As soil moisture in the forest soil surface decreases, the soil's ability to resist the collapse of its aggregated structure decreases. Consequently, even small and medium-scale precipitation events can easily cause soil dissolving. When microscopic soil particles dissolve in large quantities, soil porosity increases, and the decrease in soil moisture and increase in subsurface flow rate combine to accelerate dissolving of microscopic soil particles, thus creating a vicious circle. Finally, changes in forest soil due to global warming can have a marked effect on forest ecosystems.

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Europe has already established tentative critical levels of air pollutants based on the dose responses. Current ozone level has the potential adverse impact to plants. However, the relation with air pollutants is not clarified. The purpose of this study make GIS database to evaluate the relationship between air pollutants and forest decline, quantitatively and visually, and proposes critical level mapping method. The observation data, such as the forest decline monitoring data, the long term monitoring data of air pollutants and the meteorology data was collected. Geostatistical analysis (kriging method) was applied for making oxidant based accumulated exposure Over a Threshold of 40 ppb (A0T40) map from 1975 to 2001. And, the relation between air pollutants and Red pine, Larch, and Beech forest decline was analyzed using GIS database. Trials to present excess maps of pollutants would help a risk assessment of the impacts on forests health using critical levels evaluated by exposure experiments. AOT40 seemed to be effective as an index of the vegetation influence evaluation.

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Caspian Sea is the largest landlocked water reservoir in the world with an area of 378, 000km², its surface lies on 28m below the global sea-level. A key feature of Caspian Sea is that its sea-level has progressively risen by more than 2.5 meters since 1977, and it undergoes a cyclic fluctuation afterwards. The cause and effect of the sea-level rise and its impact on the surrounding coastal topography and environment are worth examining, because the outcome can be applied to studies on future global sea level rise and its impact.
This study introduces the present status of the sea-level rise and the existing research work to investigate the cause of Caspian sea-level rise. Furthermore, this study discusses the Caspian sea-level fluctuation effects on shoreline changes.

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The present author has performed the investigations of coastal pollution by drifted garbage in Japan islands since February 1997. It is become clear through the author's study that a large amount of garbage drifted around the coastal arrears like plastics, bottles, cans and so on, becomes the main factor of the coastal pollution. In addition to Japanese garbage, the garbage from neighboring countries such as China, Taiwan, Korean and Russia are fairly contained in the garbage. In this report, especially, some discussions are canied out about both the problems of mangrove pollution in Iriomote island of Okinawa and the possibility of injurious chemical substances dissolved by the decomposition of drifted garbage. Then, the problem of coastal pollution by drifted garbage is a serious problem in the coastal environment in Japan. It is strongly required that both the prevention measures and the way of depositing the drifted garbage must be established in a hurry.

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Before Meiji Era, Ishikari river was nearly primitive river. Beginning development of Hokkaido, river basin development and improvement were carried out. And it was thought that sediment supplied from Ishikari river to river mouth was significantly changed in nearly 100 years. In this study, about 3m columnar cores were obtained in Ishikari bay, and 14c Measurement with Accelerator Mass Spectrometry and zinc content analysis were conducted. In the result, it turns out that the amount of sediment deposition increased more than 10 times in the past 90 years. Moreover, velocity of shoreline advance was estimated in nearly 100 years.

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Spectral measurements of downward irradiance and upward radiance were made in the upper Gulf of Thailand to construct an optical model for ocean color remote sensing in turbid waters. Simultaneously, chlorophyll-a concentration, suspended solid concentration, and absorption coefficients of chlorophyll-a, particulate matter and CDOM were measured. Inorganic suspended solid (ISS), which is high scattering property, was also measured as an ignition loss of suspended solid.“Measured” subsurface reflectance was compared with “estimated” that to evaluate the optical model. The measured subsurface reflectance was calculated from spectral radiation measurements. On the other hand, the estimated reflectance was derived from the optical model with absorption and backward-scattering coefficients of in-water substances. The absorption coefficients were used the measured values. Although the backward-scattering coefficient of phytoplankton was used the equation given from previous study, that of ISS was estimated on the basis of Mie theory using the measurement of its absorption coefficient and size distribution. The estimated reflectance agrees with the measured reflectance in the case of lower ISS concentration, but that is 2 times as high as the measured in the case of higher ISS concentration. This mainly cause is an overestimation of the ISS backward-scattering coefficient. It is necessary to improve the estimation method and to conduct measurements in various ocean conditions.

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Surveys were performed on disasters caused by Indian Ocean tsunami which occurred in December 26, 2004. Surveys were done in Sri Lanka and in Indonesia. Cooperative works with professors of domestic universities, who graduated from Japanese universities were the core of the survey works. From the survey results, varieties of disaster mechanisms were found. Local natural conditions and social conditions give big influences on the mechanism. In order to promote an appropriate post tsunami rehabilitation and environmental restoration process, cooperative works with local professors and engineers are essential.

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We are increasingly aware of various benefits that mangrove forests provide us for our environment. The great tsunami occurred off the west coast of Sumatra Is. in 2004 leads us to look at another aspect of mangrove forests; their damage reduction capacity. This study discusses hydrodynamic functions of mangrove forests to attenuate tsunami waves. In order to quantify the dumping effect, a mathematical model is proposed. The present analysis reveals that universal properties on mangrove-tree configurations and on physical strength against tsunami sweeping power should be clarified for further improvement of the model predictability.

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By the Entry into forth of the Kyoto Protocol, reduction of CO₂ discharge became a big social duty in a citizen and activity of a company. Quantitative recognition for adischarge and fixation is necessary to achieve this aim. In this paper, Environmental Capacity of CO₂ fixation of River Basin was calculated on the Three Metropolitan Areas in Japan by using GIS. Environmental Capacity of CO₂ fixation set it as quantitative relation of CO₂ fixation and CO₂ discharge. And, fluctuation of Environmental Capacity of CO₂ fixation was calculated in Lake Biwa- Yodo River basin and Yamato River basin.

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Metals have toxicity property leading to adverse effect on human health and become scarce resource. If metals in end-of-life goods (wastes) are controlled or treated inadequately, they will eventually result in high environmental risk on human health and ecosystem and valuable resource loss. Treatment and recycling process of solid waste is last stage in goods' life cycle and also critical stage to determine whether heavy metals are released to the environment or not. This study aimed to estimate metal flow in solid waste management system and to evaluate quantitatively environmental burden. By integrating output values in each process, metal content in composition of household waste was estimated. For most metals except Cr, total contribution rate of paper/textile/plastics, bulky waste, and incombustible waste is over 80%. Approximately 40% of Cr originated from plastic packaging. Several SWM scenarios showed that the leaching potential of metals to the environment was quite small and most metals were transferred to the landfill.

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