• Title/Summary/Keyword: Coastal urban area

Search Result 175, Processing Time 0.027 seconds

A Study on the Chemical Components of Acid Deposition (산성 강하물질의 화학적 성분에 관한 연구)

  • 권오영;윤오섭
    • Journal of Environmental Health Sciences
    • /
    • v.20 no.2
    • /
    • pp.39-54
    • /
    • 1994
  • Dry and wet deposition samples were continuously collected by deposit gauge. In Bulkwang area of Seoul and Kanghwa in west coastal area of Korea. In order to evaluate the level of air pollution and its chemical composition, Bulkwang area located in Seoul and Kanghwa in west coastal area were chosen for sampling site. dry deposition concentrations, pH, electric conductivity and water soluble ion concentrations of deposit gauge were analysed. The results of comparison between urban area and coastal area were summarized as follows. Mean concentrations of dry deposition in Bulkwang was 2.807 ton/km$^2$/month (range: 5.171~1.128 ton/km$^2$/month) while that in Kanghwa was 1.990 ton/km$^2$/month (range: 3.358 ~ 1.084 ton/km$^2$/month), which showed a significant difference between two areas. The rainfall during the period from June to September in 1990 recorded 1859.7 mm which was 78.8% of its mean amount in Seoul, and 1846.9 mm which was 81.6% that of Kanghwa. In Bulkwang area, correlation coefficients of deposit chemical composition were 0.95 for SO$_4^{-2}$ and Na$^+$, 0.94 for SO$_4^{-2}$ and NH$_4^+$, 0.93 for CI$^-$ and NH$_4^+$ and 0.85 for Cl$^-$ and Ca$^{2+}$, respectively. Then, the results indicate that sulfates such as $Na_2SO_4$, $(NH_4)_2SO_4$, and CaSO$_4$ were the major chemical state of deposit. In Kanghwa area, it was considered that NaCl, $NH_4NO_3$, NaNO$_3$, and $Ca(NO_3)_2$ were the major chemical state of deposit.

  • PDF

Climate change impact on seawater intrusion in the coastal region of Benin

  • Agossou, Amos;Yang, Jeong-Seok
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2022.05a
    • /
    • pp.157-157
    • /
    • 2022
  • Recent decades have seen all over the world increasing drought in some regions and increasing flood in others. Climate change has been alarming in many regions resulting in degradation and diminution of available freshwater. The effect of global warming and overpopulation associated with increasing irrigated farming and valuable agricultural lands could be particularly disastrous for coastal areas like the one of Benin. The coastal region of Benin is under a heavy demographic pressure and was in the last decades the object of important urban developments. The present study aims to roughly study the general effect of climate change (Sea Level Rise: SLR) and groundwater pumping on Seawater intrusion (SWI) in Benin's coastal region. To reach the main goal of our study, the region aquifer system was built in numerical model using SEAWAT engine from Visual MODFLOW. The model is built and calibrated from 2016 to 2020 in SEAWAT, and using WinPEST the model parameters were optimized for a better performance. The optimized parameters are used for seawater intrusion intensity evaluation in the coastal region of Benin The simulation of the hydraulic head in the calibration period, showed groundwater head drawdown across the area with an average of 1.92m which is observed on the field by groundwater level depletion in hand dug wells mainly in the south of the study area. SWI area increased with a difference of 2.59km2 between the start and end time of the modeling period. By considering SLR due to global warming, the model was stimulated to predict SWI area in 2050. IPCC scenario IS92a simulated SLR in the coastal region of Benin and the average rise is estimated at 20cm by 2050. Using the average rise, the model is run for SWI area estimation in 2050. SWI area in 2050 increased by an average of 10.34% (21.04 km2); this is expected to keep increasing as population grows and SLR.

  • PDF

Comparison of Estimated Daily Dietary Intake of Dioxins in Coastal, Rural, and Urban District (어촌, 농촌, 도시 지역별 주민의 식품을 통한 다이옥신의 섭취량 추정)

  • Park, Jung-Duck;Huang, Ming-Ai;Im, Ruth;Choi, Byung-Sun;Yang, Jae-Ho;Bae, Yun-Jung;Jun, Ye-Sook;Choi, Mi-Kyeong
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.37 no.3
    • /
    • pp.325-332
    • /
    • 2008
  • The human population is mainly exposed to dioxins through the diet. The purpose of this study was to estimate the daily dietary intake of PCDDs and PCDFs in Korean adults residing in different regions. Subjects were recruited and divided into three groups according to the districts where they lived: rural (n=213), coastal (n=193), and urban district (n=187). Subjects were interviewed using a general questionnaire and 24-hour recall for dietary intake. The daily intake of dioxins was estimated through the use of the database of dioxins contents in 35 Korean foods. The average age of the subjects were 61.5 years for coastal district, 57.6 years for rural district, and 49.4 years for urban district. Daily energy intake was 1707.7 kcal for rural district, 1596.5 kcal for urban district, and 1493.8 kcal for coastal district. There was no significant difference in total food intake by regions. The intakes from fishes of coastal district, those from cereals, vegetables, meats, and seasonings of rural district, and those from sugars, pulses, eggs, seaweeds, milks, oils of urban area were higher than those of the other two districts. The daily dioxins intake of coastal district (0.70 pgTEQ/kg/day) was significantly higher than those of rural district (0.32 pgTEQ/kg/day) and urban district (0.46 pgTEQ/kg/day). The dioxins intake from cereals, pulses, vegetables, fishes of coastal district and those from eggs and milks of urban area were the highest among the districts. The daily dioxins intake was positively correlated with the intakes of meats, eggs, fishes, oils, and seasonings. Therefore, it could be concluded that the daily dioxins intake of coastal district is higher than that in other districts and the fish is one of the main sources in dioxin intakes. However, daily dioxins intakes of the three regions were below the level of tolerable daily intake (TDI).

A Three Dimensional Numerical Simulation of $SO_2$ Concentration in Relation with Atmospheric Flow in Pusan Area, Korea (부산지역에서의 대기흐름과 관련된 $SO_2$농도 3차원 수치모의)

  • 장은숙;이화운
    • Journal of Environmental Science International
    • /
    • v.6 no.4
    • /
    • pp.359-367
    • /
    • 1997
  • The Characteristics of atmospheric flow and dispersion of air pollutants in the mountainous coastal area were studied using three-dimensional model by the combination of land/sea breezes and transport. It was then applied to Pusan city. As the urban area considered In this study is located in a mountainous coastal area, the atmospheric flow is strongly affected by the land/sea breezes and mountain/valley winds. The typical effects of land/sea breezes on the dispersion and the characteristics of pollutants movement in the region were analysed. The model has been proved to be an useful tool to prodict real time air pollutants transport as shown by the results of application studies In Pusan, Korea which Is an urbanized coastal area with mountainous topography. It was found that the pollutants are differently transported and concentrated as going Inland by the Influence of the sea breeze with topographic changes. By comparing the pollutants concentrations of the stimulated results with those of the observational results, It is shown that stimulated results in this study are in qualitative agreement with observational ones.

  • PDF

Key Factors Affecting the Development of Public-Private Partnerships in Water and Wastewater Services in the Jiangsu Province, China

  • Oh, Jihye;Lee, Seungho
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2022.05a
    • /
    • pp.211-211
    • /
    • 2022
  • The marketization reform from the open-door policy in 1978 was not only booming export-oriented industries with foreign investment but also expanding the role of private actors in the Chinese water sector. Private Sector Participation (PSP) has become an important element in developing urban infrastructure by providing better services with advanced facilities. The rapid development of PSP-driven urban water infrastructure in China has a positive impacted on Chinese economic development, particularly in coastal areas. PPPs in some coastal areas have successfully spread out over China since China applied the first Build-Operate-Transfer (BOT) mode in the water sector in the early 1990s. The market-oriented water and wastewater, Public-Private Partnership (PPP) mechanism in the initial period of China has been transformed into a state-dominated PPP mechanism. The development pattern of the water and wastewater PPPs in China has been divided in four stages: the first period from 1984 to 2002, the second period from 2003 to 2008, the third period from 2009 to 2014, and the last period after 2015. The study aims to investigate the successful process of water and wastewater PPPs in local areas through five socioeconomic elements: export-oriented economic strategy, urbanization, cheap land policy, infrastructure investment, and water issues and climate change. In addition, the study focuses on analyzing the extent to which the Chinese government re-asserted its control over the PPP mechanism by classifying five elements in three different development Phases from early 2000 to 2020. The Jiangsu Province in the estern coastal area has actively invited PPP projects in the water and wastewater sectors. The successful introduction and rapid growth of PPPs in the urban water infrastructure has made the province an attractive area for a foreign investor.

  • PDF

Meteorological Characteristics in the Ulsan Metropolitan Region: Focus on Air Temperature and Winds (울산지역의 기상 특성: 기온과 바람을 중심으로)

  • Oh, Inbo;Bang, Jin-Hee;Kim, Yangho
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.31 no.2
    • /
    • pp.181-194
    • /
    • 2015
  • Spatial-temporal meteorological features of the Ulsan metropolitan region (UMR) were analyzed using observations and high-resolution numerical modeling. Long-term trend analysis (1970~2013) showed a significant increase of $0.033^{\circ}Cyr^{-1}$ in the 5-year moving average temperature, although detailed short-term features varied, whereas wind speed and relative humidity over the same period displayed clear decreases of $-0.007ms^{-1}$ and $-0.29%yr^{-1}$, respectively. These trends indicate the effects of regional climate change and urbanization in the UMR. Seasonal variations averaged for the most recent three years, 2011~2013, showed that temperatures in three different regions (urban/industrial, suburban, coastal areas) of the UMR had similar seasonality, but significant differences among them were observed for a certain season. Urban and industrial complex regions were characterized by relatively higher temperatures with large differences (max.: $3.6^{\circ}C$) from that in the coastal area in summer. For wind speed, strong values in the range from 3.3 to $3.9ms^{-1}$ occurred in the coastal areas, with large differences clearly shown between the three regions in September and October. Diurnal variations of temperature were characterized by pronounced differences during the daytime (in summer) or nighttime (in winter) between the three regions. Results from the WRF modeling performed for four months of 2012 showed large variations in gridaverage temperature and winds in the UMR, which displayed significant changes by season. Especially, a clear temperature rise in the urban center was identified in July ($0.6^{\circ}C$ higher than nearby urban areas), and overall, relatively weak winds were simulated over urban and inland suburban regions in all seasons.

A Study on Variation of Land-use in River Area caused by Levee Construction (제방 축조에 따른 하천공간 토지이용 변화에 관한 연구)

  • Shin, Hyoung Sub;Hong, Il;Kim, Ji-Sung;Kim, Kyu Ho
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.15 no.4
    • /
    • pp.2419-2427
    • /
    • 2014
  • This paper defines the hydro-geomorphological river area to estimate the change of the river function before/after levee construction, and proposes the methodology that calculates the river area by using GIS. The boundary of river area is determined by the 100-year potential flood inundation area without the levee effect of the flood protection. Firstly, 1918' land-use map was digitized and the changes were analyzed by comparing with 2007' digitized map. The result shows that urban/farmland zone in Mankyung river area were increased by 0.4%/11.6% and bare ground was decreased by 10.0% so that the effective use of floodplain due to levee construction leaded to better productivity, but the decrease of the environment function of the river was predicted as result of the reduction of the river area.

Study on Increase of Urban Air Temperature at Coastal Urban Area (연안도시 부산지역에서의 열섬에 관한 연구)

  • 김유근;홍정혜
    • Proceedings of the Korea Air Pollution Research Association Conference
    • /
    • 2000.11a
    • /
    • pp.379-381
    • /
    • 2000
  • 도시의 기온은 지표면 피복상태의 변화와 도시내부의 에너지 사용의 증가에 의해서 주변의 교외지역과는 차이가 있다. 따라서 도시기후의 연구에 있어서 도시와 교외의 기온의 비교 연구는 도시기상의 기초가 되어 왔다(Howard, 1883, Lowry, 1969). 일반적으로 도시가 교외보다 기온이 높은 것으로 알려져 있고 기온이 높은 영역은 도심을 중심으로 나타나면서 도시열섬(Heat Island)으로 일컸는다. (중략)

  • PDF

Characteristics of Surface High Ozone Concentration on Pusan Coastal area, Korea (부산 해안지역의 고농도 오존 발생 특성에 관한 연구)

  • 전병일
    • Journal of Environmental Science International
    • /
    • v.9 no.4
    • /
    • pp.295-302
    • /
    • 2000
  • This study was conducted to investigate the characteristics of surface ozone concentration and occurrence of high ozone concentration using hourly ozone, nitrogen dioxide and meteorological data for 1997~1998 in Pusan coastal area. Monthly mean ozone concentration was the highest at Dongsamdong in Spring(35.4ppb), at Kwangbokdong in Fall(25.1ppb) and the lowest Dongsamdong(22.2ppb) and Kwangbokdong(16.0ppb) in Winter. Relative standard deviation indicating clearness of observation site was 0.42 at Dongsamdong and 0.49 at Kwangbokdong that is similar to urban area. The diurnal variation of ozone concentration of Dongsamdong and Kwangbokdong showed maximum at 1500~1600LST and minimum 0700~0800LST that typical pattern of ozone concentration. In ozone episode period(Sept. 10~15, 1998), diurnal change of ozone concentration was very high, and ozone concentration was related to meteorological parameters such as temperature, relative humidity, wind speed, cloud amount and radiation on a horizontal surface. During the episode days peak ozone concentrations are much higher than the normal values, wind speeds are always lower, and solar radiation is high with the exception of the September episode.

  • PDF