This paper demonstrates the numerical simulation of three dimensional flow pattern for vehicular exhaust dispersion in the street canyons. The wind flow around buildings in urban is computed by the SIMPLEST method. The convection-diffusion equation was used to compute the NOx concentration level near buildings. Details are given of important boundary conditions and turbulence quantities variations. The simple turbulence model was used for unisotropic viscous effect. A control-volume based finite-difference method with the upwind scheme is employed for discretization equation. The simple turbulence model applied in this study has been verified through comparison between predicted and measured data near buildings. By the predictive results, the updraft induced by the presence of high-rise buildings is important in the transport of street level pollutant out from the street canyons. Our suggestion for reducing ground level pollution is to have high-rise buildings constructed or to reduce the channelling effect of street canyons.

Osancheon creek is located in the southwest of the middle area in Korea. Weed community around the Osancheon creek, where various disturbances exert a bad influence directly on its community by human work or nature, was surveyed phytosocialogically. Our surveys have been accomplished from June, 2003 to September, 2003. Weed communities formed around the Osancheon creek were divided into several patterns and analysed. They have been divided into 8 communities. Community A: Humulus japonica community, B: Phragmites communiscommunity, C: Persicaria thunbergii community, D: Zizania latifolia community, E: Miscanthus saccharilflorus community, F: Echinochica crusgalli community, G: Typha orientalis community, H: Sataria viridis community. The flora surveyed in these communities was constituted of 19 families, 36 genera, 4 varieties, and 40 species. Wild plants such as Artemisia princeps var. orientalis, Erigeron annuus, Bidens frondosa, Aeschynomene indica and Oenothera odorata were mostly light loving plants and higher resistant plants against the disturbance. Our result from the ranking all surveyed areas by the Bray-Curtis ordination method was very similar to the results from phytosocialogical table work.

The short-term version of Industrial Source Complex Model(ISCST3) was evaluated for estimating short-term concentrations using criteria pollutant(SO2, NO2, CO, PM10) data form emission inventory of Young Tong area in Suwon for the year 2002. The contribution of pollutant concentration from point, line, area sources was found 21.8, 76.5 and 1.6%. Statistical parameters, such as correlation coefficient, index of agreement(IA), normalized mean square error(NMSE) and fractional bias(FB) were calculated for each pollutants. The model performance were found good for PM10(82%) and NO2(69%), but poor for SO2(34%) and CO(13%).

The purpose of this study is to analyze the impact of land-use and population change in rural area by new expressway. Chungbu expressway constructed in 1987, going through the south area of Kyunggi province from Seoul, was selected as a case expressway, and also 2 cities and 18 subdivisions of county in its surrounding area, as a case study area. To analyze the change characteristics before and after the construction, land-use maps of 1986 and 1996 were collected, including the census data for the years in cities and counties yearbooks. Remote sensing technology was applied to classify the land-use maps with six types of land use. Geographic information system was also used for spatial analysis, such as the land-use and accessibility changes. A 5 km buffer zone from interchange of the expressway showed about two times increase of urbanized built-up area than a 5 km buffer zone from the expressway. Accessibility from Seoul and cities was improved in most areas, which is accessing to Seoul through existing Youngdong expressway. Ten rural areas showed increased population with accessibility of average 52 minutes to Seoul and 19 minutes to cities, while eight areas showed decreased population with average 73 minutes to Seoul and 35 minutes to cities. This shows that the threshold value, which is time distance to Seoul and cities for population increase or decrease, one and half hours, respectively. Urbanized area was increased in most areas, even in population decrease areas, so this indicates that there are thinning rural areas, increasing urbanized area while decreasing population.

As a pre-step research to make land-use planning in the region level, this study aims to analyze some probability pattern representing transition probabilities from farmland to others using the sequential detailed digital land-use maps. Kinki and Chubu regions of Japan, which have Osaka and Nagoya cities as their center places respectively, were selected as test regions in this study. The 10m grid land-use maps for four time series at every 5 year from 1977 to 1992 were used. In this study, the regions were divided into three sub-areas 10km, 20km, and 30km according to distance from center cities, respectively. The correlation coefficient (CC) between sub-areas with same distance in the two regions was calculated to analyze whether or not the two regions have common points in the pattern of land-use conversion probability from farmland to other types. The probability distribution of the converted areas which were moved to the urbanized area (residential, commercial, industrial, road, park and public facility areas) was about 40~70% for both all periods and sub-areas. According to distance from city centers, the probability moved to the urbanized area was about 60% at 10km area, and 40% at the 30km area, which means that the values we decreased gradually, while in the case moved to the forest and the etc areas, the values were increased slightly. The CC analysis from the paddy field and the dry field to the others separately showed that there is high correlation in the probability pattern between the two regions.

This study was carried out for reading the change of local meteorological environment according to dam construction of Nakdong-river using numerical model. The study used PSU/NCAR Mesoscale Model version5(MM5) for inquiring effect of formation of artificial lake after dam construction. The colleague simulated temperature mixing ratio, latent heat flux and sensible heat flux in two cause of existing lake and not. Temperature and mixing ratio in southwest of Andong lake increased because of the air that was warm and moist above the lake moved to southwest due to the northeasterly wind. In the case of existing lake around Andong, latent heat flux increased much in the daytime after sunrise. However, sensible heat flux decreased but it didn't change distinctly in southwest of Andong like the other values.

In order to evaluate the relationship between geochemical characteristics and benthic facies of the sediments from the Oenaro Island where red tide proliferation is first observed every year including this year, surface and short multiple core sediment samples were analyzed in terms of geochemical and benthic facies variation. The contents of organic carbon, carbonate, and sulfide gas were relatively low. The variation in C/N ratios, which indicate nature of organic carbon, suggested that the organic carbon recorded in the study area is composed of mixtures of marine and terrigenous organic matters. The concentration of minor elements found at the surface and multiple core sediment samples were also low as well as the enrichment factors(Ef) for the seven heavy metals indicated that the sediment of this area is not polluted significantly. The macrobenthic faunal community comprised 61 species, and their mean density was 708 ind./m2. Polychaete worms were major taxa of this benthic community. A crustacean amphipod, Melita sp. was the most abundant species accounted for 20.7% of total abundance, and the small polychaetes such as Heteromastus filiformis, Paralacydonia poradoxa, Magelona japonica, and Sigambra tentaculata were the next dominant species. The macrobenthos around the Oenaro Island were more diverse and abundant than that in Gamak Bay. The benthic communities in the study area sustained somewhat different species composition based on the cluster analysis and the MDS ordination. The benthic community health condition at three stations seemed to be unbalanced, and slightly polluted based on the biological index such as BPI and BC. There was no clear relationship between the geochemistry characteristic and the benthic faunal facies attributed by the micro-algal blooms in this coastal area.

This study was carried out for reading the change of local meteorological environment according to dam construction of Nakdong-river using meteorological data analysis, and modeling. The meteorological data analysised are mean temperature, foggy day, precipittion day and sunshine time. As the result of analyzing meteorological data of before and after the construction of dam in Andong and Hapchon, some discrepancy were observed by month because the lakes have different effect on the region as wind field. The common phenomenons that are revealed after dam construction are increase of foggy day and decrease of sunshine time.