The Ocean Development Committee of JSCE established the Ocean Environment Research Subcommittee with a view to have it play a role as an antenna of the committee in global environment problems. The subcommittee has been making efforts to grasp the present status of researches concerning the ocean and global environment, and to survey their information sources. As the information on the subjects should be renewed steadily, it is something like an ever-lasting job. In addition we have a mind to contribute anyhow toward developing environment enhancement technology in coastal and ocean waters. In this report, two topics are introduced: one is the remote sensing technology in the ocean, and the other is the discussions at international workshops on the relationship of CO₂ and ocean, where, as an option of activities to cope with global warming, problems relating to acceleration of storage of CO₂ in the deep ocean environment were discussed.

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Historical and meteorological data show the following results;(1) Rainfall increases during atomosherically unstable period such as warm period to cold one and the reverse case. Some decades cycle can be found in strong rainfall data. Due to global warming, total rainfall and snowfall have slightly decreased. Number of sunspot is clearly related to river discharge.(2) During warm period, the number of typhoon landed in our country decreased in comparison with it during cold one. The number of storm surges during cold period was larger than that during warm one. Past 30 years had not strong typhoons which hit our country with large storm surges so that it may be pointed out that the intensity of typhoon is gradually weaken.(3) Increase of mean temperature chiefly depends on the rise in the lowest temperature in winter season. This fact shows that heat island phenomena can not be treated in the mechanism isolated from global warming.(4) Sea level rising during past 40 years in Japan does not show same trend. This is due to the effect of plate movement and meandering of Kurosio along the Pasific coast. The locality is quite important to discuss it quantitatively.

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A collaborative field observation project, named the Biwako Project, was built up in 1989 and has been developed and proceeded by a Japanese group for investigating the hydrological cycle near the land surface, which is composed of tens of members from more than twenty universtities and institutions. The original research fields of the members are rainging from engineering, agriculture to science. The aim of this project, as the title presents, understanding the hydrological cycle in and/or over the Lake Biwa basin together with establishing ways of scaling up and down the hydrological model within the scale of 100km. Specifically, what this project is heading to as goals are;(1) verification of satellite remote sensing;(2) development of algorithms/models describing hydrological processes;(3) understanding the land surface-atomospheric interactions;(4) evaluation of space/time scale effects in the hydrological cycle.

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A seminar series on economic development and environment in developing countries was conducted with particular reference to the Asian region. A range of issues including the global environmental problems was discussed by five invited speakers. While the issues presented gave an overview of problems facing developing countries today, a number of future research agenda were also identified.

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A comprehensive research project on interactive impacts between global warming and urban activities and countermeasures is in progress. Research subtopics included are: analysis of carbon dioxide emission from urban activities and emission control; biological methane production in urban water environment; evaluation of nitrous oxide emission in biological nitrogen removal from wastewater, photo chemical production of tropospheric ozone from air pollutants; modelling of long-distance transportation of green house gas; impacts of and counter measures for sea level rise in coastal cities; impacts of global warming on urban infrastructures; impacts of global warming on hydrology in urban area. A developed simulator for material flow and heat recovery in urban area is introduced. Demand of energy for various purpose in various land use in each season in day or night is displayed. On the other hand, amount of sewage flow, which determines the available heat from sewage, is displayed along main sewer pipes.

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Roles of global land use/cover studies in global environmental issues are summarized.Major research results and trends are reviewed from the following viewpoints:
1) estimatiion of environmentalimpacts due to changes in land use and cover.
2) assessment of terrestrial environmental resources.
3) development of landuse models for forecasting environmental impacts and for policy evaluation and.
4) development of land use/cover data on the global scale and a computer environment to support global land use studies.
There have not been reported an enough numbers of researches on development of land use models at the continental and global scale and needs for further intensive studies are identified. It is very necessary to develop databases of land use/cover data which allow time-series analysis.

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With respect to global environmental problems such as global warming, ozone layer depletion and deforestration, it has been a primary proposition to achieve sustainable development while protecting the global environment for the human society. There is a growing concern that human activities have been increasing the atomospheric concentration of greenhouse gases such as CO₂ and that these increases may adversely affect natural ecosystems and social environment through rises of temperature and sea level.
As one of the largest source of greenhouse gases, the energy sector is expected to work for a formation of energy supply system with lower CO₂ emissions. The Energy and Civil Engineering Committee investigated on the major subjects with focus on the global warming problem from the perspective of energy and civil engineering at its Subcommittee on Environmental Technology from fiscal 1990 to 93.
In this symposium, CO₂ emission control in the energy sector which appears to be a primary countermeasures at the moment will be reported.

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In view of increasing role of the nuclear power generation from the standpoint of the global environment problem, it is of utmost importance for civil engineers to expand nuclear power plant sites by developing advanced siting technologies and related environment enhancement technologies around the sites as well. The Nuclear Power Civil Engineering Committee in JSCE is doing wide-spectrum activities to systematize these technologies which have been studied so far in several research projects. In this paper these activities are outlined with special emphasis on pertinent technologies to realize the advanced sitings and the environment enhancement.

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This paper describes an important relationship between global environmental issues and the work of civil engineering consultants, demonstrating need for classifying important issues and developing required countermeasures. The paper also examines present, direct approaches to developing solutions to these issues, as well as procedures for environmental preservation and approaches for carrying out oversea's projects through the evaluation of these experiences. In addition, presented here are possible contributions that can be made by engineering planners and designers via the preparation of appropriate mitigation measures for environmental loads in terms of the introduction of civil engineering facilities.

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In a food processing plant in Yunotani Village in Niigata Prefecture, natural snow is conserved and its cold energy is utilized. For a whole year, five hundred tons of fresh vegetables are stored under low temperature. In the world, a wide area of cold region exists. The authors contend that in these areas, natural ice can be conserved, and food products can be stored for the whole year. With ice utilization as the prime objective, a field experiment is conducted in Japan's Asahikawa City in Hokkaido and in Heilonjian Province in China. Results show that even without using electricity, fresh vegetables and food prooducts can be stored under low-temperature storage facilities for the whole year. At present, for application purposes in the real world, an experiment using a 10m×10m×3m thick ice is conducted in Harbin City in China.

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Field observation were conducted at Ara-river in 1993 summer to evaluate the effect of heat balance on water temperature. The observation in the river course consists of measurements on long- and short-wave radiation, heat and vapor fluxes at water surface and measurements on vertical distribution of water temperature, saline concentration and transmissivity of solar radiation through the water body. The development of thermocline in the water body associated with net radiation was observed. It was found that the short?wave solar radiation dominates the balance of radiation, and it was also found that the heat convectively transported by flowing water is much lager than the heat generated by the radiation.

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Urbanization has been well in progress accompanied by the change of land-use due to concentration of population and consumption of a lot of energy. In particular, large-scale reclamation projects have been constructed in the coastal areas in Japan. Such a tendency is found in the world that ‘heat island’ phenomena can be appeared in most of metropolitan cities because of the temperature difference between urban and rural areas. In the present study, therefore, the effects of urbanization and construction of reclaimed islands on the local climate are examined using a 15-levels-three dimensional atmosphere numerical model with highorder turbulence modelling.

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Geotechnical investigation on coal mine fly ashes has been carried out for the last ten years as a joint research by two groups at Ibaraki University and Shimizu Construction Co. Ltd., This report reviews the results from this investigation, mainly at laboratories of two institutions which have been aimed at (1) use to reclamation and (2) utilization as a light weight geo-material.

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Japan is surrounded by the sea. Recently it has been severely and gradually contaminated by oils, dust, organic matters or radioactive substances which are drained from the human activities. And contaminations or destructions of sands on the sea·shores which is bordered on ocean has been in advanced too.
In this study, the method of estimation, using the Singing or Musical Sands for contaminated sands on the sea-shore which is distributed throughout in Japan, is proposed to estimate the quality of sands.

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In ancient days, we had a lot of clean beaches covered with “ Music Sands ” almost in Japan, but nowadays such beaches have trended to decrease due to environmental pollution of the coastal area. In this paper, several kinds of sands including “ Music Sands ” were collected from both clean anddirty beaches, and checked on the spectral reflectance of each sand using a portable photometer. As a result, we could find the difference of the spectral characteristics in each sand, and decide a value of SCI (Sandy-beach Cleanliness Index) as a parameter of the beach cleanliness. Morever, we tried to analyze the satellite data in order to grasp the clean and polluted areas for beach sands in Kyushu District.

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Recently, the condition of radioactive waste dumping in the Far Eastern seas and the Arctic Ocean by the former Soviet Union and the Republic of Russia is being identified. The waters in these areas are very narrow, shallow and close to land. To assess the impact of such actual radioactive waste dumping, it is necessary to establish a safety assessment model which can predict local effects and a more realistic assessment method.
In connection with the above-mentioned problems, investigation and research activities are being carried out by many scientists. However, it goes without saying that the behavior of radioactive substances in the seas are deeply related to the marine characteristics of the Sea of Japan and the Arctic Ocean.
It is necessary to identify these marine characteristics in order to determine the circulation of seawater in both seas, analyze the diffusion of radioactive nuclides and make assessment of exposure doses. In this paper, therefore, the author examined the marine characteristics on the basis of JODC data as well as NOAA observation data on each layer, by making arrangements and illustrations of water temperatures and salinities in the threedimensional boxes for the respective seas. The patterns of water masses classified by type were created using these distribution maps.

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Water quality of three large lakes (L. Erhai, L. Qilu and L. Dianchi) in Yunnan Province, China was studied to evaluate the eutrophication level and to anlayze its process. It was found that three lakes were polluted eutrophically though each lake had its own character. Among three lakes, L. Dianchi near Kunming city was extremely eutrophicated with TN being over 4 mg/l and TP being over 0.4 mg/l. One river flowing into L.Dianchi had more than 20 mg/l of TN and 2-4 mg/l of TP. These show that eutrophiction in this province is caused by a great amount of nutrient load originated from city, industrial and agricultulal activities. It is nesessary to decrease and control the pollution loads to conserve the spesific eco-system as soon as possible. In L. Dianchi, the concentration of nutrients was observed to decrease as the sampling points came nearer to the outflowing point. In this lake, self-purification process contribute to recover the deterionated water quality.

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Cs-137 fallout from atomospheric nuclear detonatin tests has been worldwide monitored since late 1950's. We analyzedt hese monitoringd ata statisticallya nd determinedt he characteristicso f their surface deposition.I n this analysis, the scale of space (size of compartment) a nd the accuracy of analysis (number of compartment) are determinedd ependingo n the global-scale dispersion of Cs-137. Mathematical model was developed and examined by comparing the numericals imulation with the falloutm onitoringd ata (includingt he data of Cs-137c oncentrationo f sea water).
The main results obtained in this study are sarnmarized as follows:
(1) Cs-137 deposition depends on the latitude zone but not on the altitude.
(2) Thep roposedm athematicaml odel is promisingf or evaluatingd ynamicp erformance of Cs-137 in global atomospherice nvironment and its surface deposition.
(3) Transportation rate coefficient from stratosphere to trotosphere, in trotosphere, and from trotospheret o land/oceani s highly sensitivet o surface deposition of Cs-137.
(4) Cs-137i s accumulatedm ore in surfacew atero f the North Pacifica nd NorthA tlanticO ceani n 1960' than othersa nd more in South Pacific and South Atlantic Ocean after 1970's. In deep ocean water Cs-137 is increasing more in Indian Ocean and South Pacific Ocean than the others.

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ABSTRACT;Analysis of PAN measurement in Sapporo indicated that the variation of PAN in Sapporo was highly affected by the transport from a wide area rather than the photochemical formation in Sapporo city. In this study, a two dimensional channel model for chemistry and transport in the troposphere is constructed to study the behavior of trace species at mid latitude in the northern hemisphere. Evaluation of the model performance is attempted with the results of our PAN measurements in Sapporo. The calculated seasonal variation of PAN concentrations at 140E near the surface, which shows a maximum in the late winter and a minimum in summer, presents a similar pattern to that observed in Sapporo. However the model tends to overpredict the concentrations during winter months and underpredict the concentrations during summer months.

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Atmospheric concentration of SO₂ and NO₂ were measured at Khabarovsk, Yakutsk and Norilsk cities in Siberia in summer of 1993. In the measurements diffusion samplers were used, which are made of plastic pot packed with reagent soaked filter papers. In Khabarovsk, atmospheric concentration of NO₂ and SO₂ ranged from 5 to 12 ppbv and from 2 to 5 ppbv, respectively. In Yakutsk, they ranged from 0.3 to 10 and from 1 to 2 ppbv, respectively. In Norilsk, concentration of NO₂ and SO₂ ranged from 2 to 6 and from 11 to 44 ppbv, respectively. Concentration of NO₂ was about the same in Khabarovsk and Yakutsk, but SO₂ concentration was much higher due to poor emission control of SO₂ from mining factories.

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Acidic deposition has become a major worldwide environmental problem, and the effects of acidic deposition has been noticeable through dying forests, increasing acidity of lakes and reservoirs, and the destruction of outdoor sculptures and buildings. And it often touches off problems beyond the borders due to that the acidic pollutants may fall several thousand kilometers away from the emission sources. It is necessary to establish what the current situation is in these areas. The objective of this paper is to describe the present state and trends of acidic deposition and its countermeasures in China. The nationwide research projects, major research fields involved, the control policy and mitigate measures are also discussed in this paper.
The results show that the acidic deposition mainly distributed in the south of Yangtze (Chang Jiang) River, few acidic depositions were recorded in northern and eastern China. Local pollution is the major reason responsible for acidic deposition, while long range transport plays a relatively minor role. The area affected by acidic deposition accounts for about 6.8 % of the total area of the state, and the area with serious problems accounts for 11.7 % of the total area affected by acidic deposition. The problem of acidic deposition shows a tendency that it is more serious in southern area than in northern area. pH of precipitation in fall and winter is usually lower than that in spring and summer. SO₄⁼represents the major reason for the acidic deposition in China. A significant relationship exists between pH and atmospheric concentration of SO₄⁼ and concentration of particle material.

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The global environmental problems have socially become very important in recent years. Both the fields of the civil engineearing and ground engineering are confronted with the many difficulties that must take the new approaches to the natural environmental problems. In this investigation, the present authors mainly discusse about the natural environmental problems between soil ground and acid rain. At first, the present authors try to describe concretly the main roles and important subjects of ground engineers and soil investigators. Next, based on the results of chemical microanalyses about rainfall and snowfall obtained from the foot of the Mt.Fuji and Yokosuka city, the the real condition of acid rain is shown. Also, test results make it clear that the clayey soils have stronger ability to absorb acidity than the sandy soils.

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Using the simulated acid incident precipitation or throughfall, saturated soil column experiments werecarried out. Total ion concentration of throughfall is higher than that of incident precipitation. When simulated throughfall was used, acid neutralization by cation exchange was reduced, and Al concentration in effluent was raised. Among co-existing cation in simulated throughfall, the effect of calcium ion and potassium ion on soil acidification were more important than that of sodium ion. Taking account of the experimental results and the effect on plant ecosystems, We discussed about the appropriate index to evaluate the degree of soil acidification.

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Methodology for the assessment of vulnerability to sea level rise and climate change was studied in order to apply South Pacific island countries such as Fiji and Western Samoa. The main purpose of this study is to introduce indigenous characteristics of the countries to the assessment. The characteristics include subsistence economy, close ties of people to land through customary land tenure, extended family structures, etc. The approach adopted here recognize the coastal zone as a set of “coastal systems”. Each coastal system is made up of “sub-systems”, which consist of “coastal sub-system elements”. The concept of “vulnerability and resilience” was considered for assessing each system. Semi-quantitative scoring methods were used to judge the vulnerability and the resilience of each system. As the results of testifying the methodology at study sites in Fiji and Western Samoa, it can be concluded that the present method is effective to reflect the indigenous characteristics in South Pacific.

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Since global warming drew people's attention in the late 1980s, many efforts have been paid to evaluate the vulnerability of the coastal zone to sea level rise and climate change. In this paper, a brief introduction is made to the world-wide or regional initiatives, such as the IPCC, global vulnerability assessment, the US EPA and the University of Maryland, Asian Development Bank and US Climate Institute, and the South Pacific Environmental Programme. An overview is presented for the global picture on the possible impacts of sea level rise, such as populatio n at risk, wetland at loss, rice production at loss, and cost for coastal protection by summarizing the results of the above activities.

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Most of previous studies on the problem of sea level rise focused on prediction of sea level rise and measurement of physical damage cost, but did not consider uncertainty and psychological damage on the risk of storm surge disaster. Moreover, relationship between household's damage cost by sea level rise and benefit by countermeasures against sea level rise was not clear in those studies.The purpose of this study is to define and measure household's da mage cost and benefit under uncertainty by applying concept of equivalent variation to expected utility level of household's, to clarify that relationship.

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Inner bays have often suffered from storm surge disasters. If the sea level rise and typhoon intensification under global warming happen, the frequency of storm surge disaster will increase. In the present paper, we predicted storm surge andsea waves in Tokyo Bay considering sea level rise and typhoon intensification. Hazard maps of storm surges were presented due to the prediction. Then, we simulated the inundation due to overtop and overflow at Urayasu and Makuhari. At Makuhari, major buildings were considered as a boundary condition by using finite element method. As a result, we suggested the method for the prediction of storm surge and sea wave disaster accelerated by the sea level rise and typhoon intensification under global warming.

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Many people have warned the global warming and proposed several countermeasures to solve this problem. However, we don't have strict determination of this climatic changes. In this research, the authors analyzed the germination data of horse chestnut which had been recorded in Geneva from 1808 up to the present. The germination in recent years set in always earlier than before. Phenological data was expected to show distinct changes of the climate. Firstly they made the phenological mechanism clear by using the temperature data. And secondly they specified the factors in this mechanism which had changed during this recording period, and investigated the usefulness of phenological data as an index of long-term climatic changes.
Usually, germination was supposed to occur when the accumulated value of daily temperatures reached a constant value. In this analysis, on the law of Arrhenius they transformed the daily temperature into the number of days, and used it for estimating of germination date. But the precision was not sogood. Because it was difficult to apply this technique to the long-term data. And then they analyzed the temperature within the fixed period before germination, and found that about 30 days before the germination influenced it greatly.

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Global warming affects human morbidity, mortality and health. We describe shortly the effects on human health, and focus in malaria as one of the important diseases affected by climatic change. Models on vectors of malaria, i.e. Anopheles, and temperature dependency of sporogonic development of parasites in the mosquito were coupled in order to estimate the eco-climate sensitivity of malaria epidemicity. Combined the models with estimated global climate change pattern of general circulation models, an impact on global human health under intensified malaria risk was assessed and its implication was discussed.

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Potential contribution of nitrous oxide (N₂O) production during wastewater treatment is discussed based on experimental results. Laboratory experiments using artificial substrate showed that N₂O can be produced both innitrification and denitrification of wastewater. Conversion to N₂O was as high as in the order of some tens percent of the applied nitrogen. Favorable conditions for production of N₂O in denitrification are insufficient organic source, low pH and short solid retention time. Low dissolved oxygen, short solid retention time and presence of organic matters can provoke N₂O production in the nitrification process. These conditions are similar to the operational conditions of actual nitrogen removal process.

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Thailand locates in sub-tropics, and it has distinct rainy and dry season. The interannual variability of monsoon rainfall is extremely large, which sometimes causes drought and flood in this country. The prediction of the rainfall during rainy season is particularly important in this region, because the dominant agriculture here is paddy. The water deficit or surplus also sways a single or double crops of rice for the year in some particular areas.
For the better understanding of the interannual variability and the prediction of rainfall in Thailand, station raingauge data were collected and analyzed with sea surface temperature by lag-regression. Daily rainfall data from Meteorological Department of Thailand, and SST data from Japan Meteorological Agency were used in monthly scale. The results shows that there are statistically good correlation between them, especially at the Gulf of Thailand and in the tropical Atlantic Ocean. An operational rule using the difference to the former year is proposed and it can predict the excess and shortage of seasonal rainfall by 80% qualitatively. It was also shown that there is a good correlation of interannual variation between Southern Oscillation Index and the rainfall in Thailand.

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Fagus crenataforest in Japan has decreased until these days, because of cutting for timber and development for resort. But it has a lot of environment preservation functions and various plant and animal species, so it's important forest ecosystem for human being. Based on a phytosociological survey, the geographical variation of the species composition and the distribution of Fagus crenataforest in Japan, were analyzed and discussed. It has difference in species composition between Japan sea side and Pacific Ocean side. According to our analysis, 5 associations were recognized. And the snow environment and the thermal environment of each association were analyzed. We think our ecological basic data about Fagus crenataforest help the preservation of it.

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Stepwise regression analyses of mean and standard deviation of monthly precipitation on mean and standard deviation of monthly air temperature are carried out for sixty observation stations over Japan; Six types of regression models are examined based on AIC criterion, so that the optimum regression model for each observation station is obtained. Using the optimum regression models seasonal changes of mean and standard deviation of precipitation are estimated for three warming scenarios; 1) monthly 0.5°C up, 2) monthly 1.0°C up, and 3) 1.°C up averaged over year.

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The satellite data is very useful for observation of the regional environment. However, it has been rather difficult to obtain quantitative data from satellite image data. Recently the number of ground observing stations has been increasing. The interpretation of the image data became easier and clearer. This report shows some examples how to utilize the NOAA data for observation of environment. i.e., the observation of snow covered area, estimation of evapotranspiration and evaluation of NPP are shown as examples. Snow covered area can be obtained correctly by comparing multi-spectal senser. Snow map made from some images makes possible to evaluate snow storage. Evapotranspiration can be estimated by considering the correlation with NDVI which is calculated from the satellite data. The distribution of NDVI also makes possible to evaluate Net Primary Production.

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We have developed a new runoff model for dam watersheds that takes into account forest conditions. However, our information on forest conditions was limited. Accordingly, we have examined applicability of Normalized Vegetation Index (NVI) by Landsat TM data to understand the forest conditions. In this report, we studied Yanase dam watershed of Kochi Prefecture, Shikoku island. The slopes in this area were very steep, and there were many Sugi plantations with various stand ages. This time we studied (1) seasonal and annual changes in cut-over areas, (2) relationships between NVI and Sugi stand age. From the above results, it was found that NVI data were useful for the observation of forest conditions.

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The magnitude of the impact on energy consumption and the environment is becoming heavily depending on national and urban spatial structures such as land use and transport. This paper attempts to review the researches dealing with the relationship between spatial structure and energy and/or the environment, and to understand the trend of the researches. Their main features are summarized by approach method and study area. Suggestions are also given for the future research in order to make further understanding of the spatial structure-energy/environment interaction.

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A model to find a balance of human impacts and the global environmelt from the view point of food and energy is discussed. This model consists of satellite data and Edmonds & Reilly (E-R) model. The farmer combined with weather data and soil maps (ex. ISRIC data) can monitor the suitable place for cultivation and plantation and estimate the amount of CO2 fixation. And the latter can estimate the CO2 discharge. From the model proposed in this stud, ywe can find the CO2 discharge when the population becomes the limit by E-R model, and can find the place for cultivation and plantation simultaneously

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This report includes evaluation method of technologies in the three major areas of Hazardous waste, Solid waste, and Energy-related airborne waste. The methodology for determining the optimum environmental technology areas that should be investigated by the construction industry ought to be completed in a seven stage process that includes the following steps: 1) Initial Search, 2) Development of Detailed Hierarchy of Objectives, 3) Ranking and Weighting the Objectives, 4) Preliminary Reduction, 5) Final Analysis and Scoring for Candidates, 6) Sensitivity Analysis, 7) Choice and Justification.

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An attempt of reforming a new habitable tideland for the mudskippers was made after repairing revetments. The objectives of environmental education, i. e. 1. awareness 2. knowledge 3. attitude 4. skill 5. evaluation 6. participation, was applied to the construction, in order to conserve the mudskippers. According to the application of environmental education, the conservation was not only carried out with knowledge of the constructors or scientists, but also with opinions and effort of the public in general.

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Importance of cleaner production (CP) as a measure for sustainable industrial development is increasingly recognized worldwide and it is urgently requested to clarify the promoting and inhibiting factors for CP so that appropriate industrial and environmental policies would be adopted in developing countries for the promotion of CP. With the aim of clarifying the background of CP introduction in Japanese industries, detailed case studies were carried out for four enterprises in Chiba Prefecture. Through the case studies, stringent enforcement of environmental regulations and possibility of cost saving were identified as the two major driving forces of CP. This finding was compared with the findings of a comparative study on CP introduction in ten Asian countries and it was concluded that weak enforcement of environmental regulations was one of the most important inhibiting factors for CP introduction in developing countries.

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The problems of inadequate treatment of human excreta and wastewater in the urban area of developing countries are becoming more and more serious. Funds for the environmental improvement are, however, strictly limited at the present condition. Considering this situation, this study aims at the development of a simulation model to identify the best plan for sanitation system improvement with which adverse effects by domestic wastewater could be minimized. In this model, BOD loading is used as the indicator of environmental aspect while fecal coliform is used as that of health aspect. Actual data used in model were collected in Cirebon city located in the western part of Jawa Island, Indonesia.

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Reduction of greenhouse gases (GHGs) emission is one of the most important targets to be commonly achieved by every country, as described in the Framework Convention on Climate Change (FCCC). However, the significance of this target may be different country by country in translating it into its national policy. There might be some conflicting interests particularly between developed and developing countries. Taking Indonesia as a model, this report discusse how global warming issues should be dealt with in the individual nation's policy of developing countries. It also considers the importance of damage alleviation measures in coping with global warming and climate change.

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Technological level of East Asian Countries is still low compared with that in industrialized countries. Backwardness, however, implies advantages and great potential for learning from the experiences stored in other countries.In this sense, East Asian countries have great opportunities for achieving economic growth while restraining the increase of energy consumption by using appropriate technologies. This study makes a brief review of the possibilities particularly for China and South Korea to achieve sustainable development objectives by introducing advanced technologies available in industrialized countries like Japan.In addition to technologies, proper intervention by government is necessary to guide environmentally sound business activities. Intervention could be done either by laws and regulations, economic instruments, or dissemination of relevant information. It can be pointed out that the cooperation with Japan would be especially important, in view of their geographical location in East Asia.

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Thailand is one of ASEAN countries, and have much progressed in economic conditions. At the same time environmental pollution, such as air pollution, water pollution, is the seri ous problem, which would restrain its progress in the near future.The auther had been stayed in Bangkok for two months as a visiting facultyin AIT, sponsored by Japanese Ministry of Edu-cation and Culture.During his stay, he observed the environmental conditions.This paper con-sists of his experiences and analysis, in order to propose the future environmental programmes.

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LAO PDR, mainly located within the watershed of the Mekong River, is a landlocked country with a total area of 236, 800 km². The GDP per capita is only about US$ 220 in 1992 and the total population is 4.36 millions. The forest coverage, which is estimated about 47% in 1981, has decreased more than 20% during these fifty years because of commercial logging, forest fire and shifting cultivation that the three-quarters of the farmers are practicing even nowadays. This paper mentioned (1) analysis of socio-economic, hydrological and forest situations, (2) strategic approaches for environmental resources management and improvement of living conditions.

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From the navigation view-point, the change in water discharge of river is one of the most important factors. Since the South-East Asian rivers are in the tropical monsoon region, this variation is normally large. For these rivers, water discharge is extremely small during the dry season, from Dec. to Apr., and large during the rainy season from July to Oct., The difference of these two extremes of water discharges is high as 200 times for Irrawaddy river at Mandalay, 21 times for Mekong river at Kratie, 22 times for Chao Phraya river at Chao Phraya Dam and is supposed to be one of the highest among large rivers in the world.
Another important factor may be the river morphology, which is normally determined by the conditions at the annually maximum or bankfull discharge. As for the frequently flooding rivers, the conditions just before the bank collapse are influential. Most of the rivers in South-East Asia are among the meandering regime with the formation of alternative bars at both banks of the river. Thus the river bed morphology can be predicted empirically since the formulation of alternative bars can be modeled. These alternative bars form during season of high water level, and remain even after the water level reduces. Therefore, they may become obstructions for navigation during dry season.
The variation in the water level of South-East Asian rivers during one year can much affect the transport capacity, which may become critical during low-water period.

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