• Title/Summary/Keyword: Urbanization

Search Result 1,447, Processing Time 0.178 seconds

A Study on Variation in Annual Water Balance (도시화에 따른 수문기후변화 I (연 물수지 변화 분석))

  • Rim, Chang-Soo;Chae, Hyo-Seok
    • Journal of Korea Water Resources Association
    • /
    • v.40 no.7
    • /
    • pp.555-570
    • /
    • 2007
  • The effects of climatic changes owing to urbanization on annual water balance have been studied. In this study, 56 meteorological stations including Seoul metropolis in South Korea have been selected, and the area of study site is $314\;km^2$. The meteorological station is centrally located in the study area with a 10 km radius. Land use status of study area was examined to estimate the urbanization extent, so that annual actual evapotranspiration could be estimated. Annual runoff was estimated by annual water balance approach using the estimated annual actual evapotranspiration and measured annual precipitation. Annual actual evapotranspiration was estimated by applying experimental equation suggested by Zhang et al, (2001) which was evaluated from 250 watersheds all over the world. Study results show that reference evapotranspiration is tending upwards due to urbanization; therefore, it seems that climatic change due to urbanization may increase the amount of annual actual evapotranspiration. However, the increase of residential area due to urbanization in study area may decrease the amount of annual actual evapotranspiration. The study results indicate that urbanization effect on annual trend of precipitation was not significant. In urban area, annual runoff is directly affected by annual precipitation, and compared with annual precipitation, annual variation of actual evapotranspiration was not significant even though it was estimated by using annual precipitation. It seems that the effect of urbanization on annual actual evapotranspiration does not influence on annual runoff significantly, and that urbanization effect on annual runoff Is not significant.

Urbanization in Pusan City, Korea: Changes of Traffic Volume (교통량 변화로 본 부산의 도시화)

  • Kim, Won-Kyung;Beun, Jeong-Hee
    • Journal of the Korean association of regional geographers
    • /
    • v.4 no.2
    • /
    • pp.1-14
    • /
    • 1998
  • This research concerns with the urbanization in Pusan City, the largest port city of Korea focus on the changes of traffic volume from 1970 to 1994. These results are as follow: (1) Urbanization of Pusan City has progressed with increasing the efficiencies of streets. At the first, it's ribbon developed along the main artery toward inland. Urbanization is the process of bear a resemblance to characteristics of CBD. It has both expansion and diffusion processed, simultaneously. Urbanization has progressed centered certain nuclei and developed with more varieties are ally and temporally. (2) Traffic volumes according to times which go and return to piers affected to the traffic pattern of the some parts within the city, it is one of characteristics in port city. Variation of traffic volumes according to times much greater at the nearer streets the piers and connected street with it than the rest of the areas within the city. Rivers and mountains affecting to the traffic pattern and play roles of diffusion barriers for urbanization. (3) In the mid-1980, regions which locate along the main arteries had reached to as same level of urbanization as central part of the city. And higher ranked central places within Pusan City developed toward pattern of CBD in the past. It suggests that these central places revoluted to the recreation of CBD function in the past. (4) Urbanization has developed as same as cell differentiation in process, and it encouraged the more greater variation among the regions and become clear the hierarchy of central places within the city.

  • PDF

Comparison of Health Status of Japanese Tree Frog (Hyla Japonica) in a Rural and an Urban Area (농촌과 도시 지역에 서식하는 청개구리 (Hyla japonica)의 건강도 비교)

  • Park, So Hyun;Cho, Kang-Hyun
    • Ecology and Resilient Infrastructure
    • /
    • v.4 no.1
    • /
    • pp.71-74
    • /
    • 2017
  • Urbanization is a major driver of global amphibian declines. For the study on the effect of urbanization on amphibians, we compared the growth and the health status of Hyla japonica amphibians collected in the urban areas of Incheon and in the rural area of Gapyeong, Korea. The size and weight of Hyla japonica body in the urban area were smaller than those in the rural area. However, there was no significant difference in their condition factors as a health indicator between the two areas. Our study emphasizes the need for research into the specific mechanism of effects of urbanization on amphibian heath status for the further understanding of the relationship between urbanization and amphibians.

도시 소하천 개발에 따른 유출 변화량의 모의기법에 관한 연구

  • 김성원;조정석
    • Journal of Environmental Science International
    • /
    • v.7 no.4
    • /
    • pp.451-460
    • /
    • 1998
  • The objectives of this study Is to evaluate the total runoff yield, peak flow and peak flow travel time depending on the urbanization, return period and rainfall patterns at the downstream of Manchon urban watershed in TaeGu City. SWM(Storm Water Management Model) is used for runog analysis based on 5 different steps of urbanization and 4 different types of Hufrs quartile according to 8 return periods. It is analyzed that the order of total runoff yield according to raiun patterns is Huffs 4, Huffs 2. Huffs 3 and Huffs 1 quartile, that of peak flow magnitude is Huffs 2, Huffs 1, Huffs 4 and Huffs 3 quartile at present development ratio. under the 60, 70, 80 and 90ft of urbanization to the 50% of urbanization by means of the rainfall patterns, the mean Increasing ratio of total runoff yield for each case is 4.55, 11.43, 16.07 and 20.02%, that of peak flow is 5.82, 13.61, 17.15 and 18.83%, the mean decreasing ratio of peak flow travel time Is 0.00, 2.44, 5.07 and 6.26%, the mean increasing ratio of runoff depth Is 4.51, 11.42, 16.02 and 20.05% respectively. the mean increasing ratio of total runoff yield by means of each and 19.71%. Therefore, as the result of this study. it can be used for principal data as to storm sewage treatment and flood damage protection planning in urban small watershed.

  • PDF

Study on the Variation of Nighttime Cooling Rate Associated with Urbanization (도시화에 의한 야간 대기 냉각율 변화에 관한 연구)

  • Lee, Soon-Hwan;Park, Myung-Hee;Kim, Hea-Dong
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.24 no.1
    • /
    • pp.83-90
    • /
    • 2008
  • In order to clarify the urbanization intensity of Daegu Metropolitan and its characteristics, comparative study on the variation of the cooling rate of two different sites was carried out using observation data for 40 years by Korea Meteorological Adminstration. Daegu Metropolitan and Chupungnyung represent well urbanized and rural areas, respectively. In comparison with Chupungnyung, yearly mean temperature at Daegu Metropolitan increases rapidly and especially the differences of minimum temperature increasing rate during 40 years becomes greater. These differences of regional warming are caused by the different urbanization intensity between two sites. And the impact of anthropogenic heat due to urbanization should be stronger in nighttime than in daytime. Sensible heat advection by regional wind during 6 hours from 18 LST contributes to atmospheric cooling. For this reason wind speed is in proportion to cooling rate of atmosphere. However, wind after 24 LST induces the warm air advection and makes decrease the cooling rate in urban area. Although the cooling rates between Daegu Metropolitan and Chupungnyung are some different, the variation tendencies of cooling rate of two site are almost same. Therefore atmospheric cooling rate in nighttime tends to be associated with the intensity of wind speed.

Analysis of the Urbanization Effect on Hydrologic Response

  • Jung, Young-Hun;Kang, Na-Rae;Lee, Seung-Oh;Kim, Hung-Soo
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • /
    • pp.944-944
    • /
    • 2012
  • Urbanization leads to a change of hydrologic responses because impervious area is increased by urbanization. Decrease of groundwater recharge and increase of overland flow are general hydrologic characteristics caused by urbanization. This can be a source of damages such as increased flooding and reduced groundwater levels. Daily streamflow in Gabcheon watershed, South Korea is simulated by ARCSWAT model, an extension of SWAT2005. After calibration and validation of model, the simulated daily streamflow from 1997 to 2001 are statistically analyzed. The phenomenon that $T_{Qmean}$ is inversly proportional to coefficient of variation for the simulated daily streamflow is demonstrated. Also, hydrologic response was more influenced by weather than land use for high flow. This study also examines the effect of land use change on daily streamflow with spatially and quantitatively different land use maps. The simulated stream flow is tested by Mann-Whitney method. The median between stream flows simulated for 1990 and 2000 land use maps is significantly different, but the simulated streamflow for spatially different land use maps is almost unchanged.

  • PDF

Impact of Urbanization on Hydrology of Geumho River Watershed: A Model Study (금호강 유역의 수문환경에 대한 도시화의 영향: 모형 연구)

  • Kim, Jae-Chul;Lee, Jiho;Yoo, Chulsang;Kim, Sangdan
    • Journal of Korean Society on Water Environment
    • /
    • v.23 no.4
    • /
    • pp.535-542
    • /
    • 2007
  • The Geumho river watershed located in the middle of the Nakdong river has been threatened by high population growth and urbanization. Of concern specifically is the potential impact of future developments in the watershed on the reduction of base flow and the consequent risk of degradation of ecological habitats in Geumho river. Anticipated increase in imperviousness, on the other hand, is expected to elevate flood risk and the associated environmental damage. A watershed hydrology based modeling study is initiated in this study to assist in planning for sustainable future development in the Geumho river watershed. The Soil and Water Assessment Tool (SWAT) is selected to model the impact of urbanization in the Geumho river watershed on the hydrologic response thereof. The modeling results show that in general the likelihood that the watershed will experience high and low stream flows will increase in view of the urbanization so far achieved.

A proposal for empowering slum dwellers as a viable way of addressing urbanization challenges in Katanga slum, Kampala, Uganda

  • Omulo, Godfrey;Muhsin, Musinguzi;Kasana, Ismail;Nabaterega, Resty
    • Environmental Engineering Research
    • /
    • v.22 no.4
    • /
    • pp.432-438
    • /
    • 2017
  • Slum settlement, a direct result of the rapid worldwide urbanization is a common site in most developing countries. Uganda is among the top African countries with high number of slums. The status of Katanga slum located in the low-lands between Mulago national hospital and Makerere University is a typical of many other slums within Uganda. This project proposal seeks to tackle urbanization challenges by specializing in slum upgrading as a sustainable way of curbing the menace. An integrated toilet, biogas, poultry and backyard gardening project is proposed as a channel of boosting the Katanga slum dwellers' economic, sanitation and domestic energy status. Designed to serve up to 30 households, the project will utilize residual wastes from poultry houses and toilets to produce biogas and slurry. The biogas yield will provide clean cooking fuel and energy for lighting, while the slurry used as organic fertilizers to improve vegetable yields. The social, economic and environmental impacts of the project will empower the vulnerable women and children within the slums and reduce water pollution and land degradation. This affordable project can be applied in developing countries experiencing slum settlement challenges as a strategy for reducing urbanization pressure.

The classification of biotope type and characteristics of naturalized plant habitat on the coastal sand dune ecosystem

  • Lee, Jeom-Sook;Jeon, Ji-Young;Ihm, Byung-Sun;Myeong, Hyeon-Ho
    • Journal of Ecology and Environment
    • /
    • v.35 no.3
    • /
    • pp.167-175
    • /
    • 2012
  • Coastal sand dune systems are particularly fragile and threaten the environment. However, these systems provide fundamental ecosystem services to the nearby urban areas, acting, for example, as protective buffers against erosion. In this paper, we attempt to classify the biotope types of coastal sand dune ecosystems and select an index for the assessment of the conservation value. The types of biotopes are categorized based on the vegetation map; floras are examined in order to research the effects of hinterlands on coastal sand dunes. In addition, a naturalization rate and an urbanization index for each biotope type in hinterlands are analyzed. In the ecosystem of coastal sand dunes, the urbanization index and naturalization rate shows a higher value in sand dunes with areas of road, residential, and idle land in farm villages, rice fields, and fields. On the contrary, a lower value in the urbanization index and naturalization rate is present when typical biotope types, such as sand dune vegetation and natural Pinus thunbergii forests, are widely distributed. Based on these results, urbanization index and naturalization rate should be used as critical indices for the assessment of the ecosystem of costal sand dunes.

Korean Urbanization in The Asian Context (한국과 아시아지역 국가의 도시화 경향)

  • Huguet, Jerrold W.
    • Korea journal of population studies
    • /
    • v.10 no.2
    • /
    • pp.82-98
    • /
    • 1987
  • The urban population in Asia more than doubled between 1960 and 1985, growing by 3.0 percent per annum on average. Yet during that period, the proportion of the total population living in urban areas increased only from 21 to 27 percent. This seeming paradox is explained by the relatively high rates of rural population growth in Asia, which averaged 1.8 percent over the same period. The Republic of Korea has experienced the most rapid rate of urbanization in Asia during the past century. The proportion urban jumped from 28 percent in 1960 to 65 percent in 1985. There is a clear association between economic growth and the pace of urbanization in Asia. Currently natural increase accounts for about 60 percent of urban growth, but the speed of urbanization is projected to increase after 1990, and migration, reclassification and annexation will comprise about half of urban growth, Seoul is currently the fourth largest urban agglomeration in Asia, and its population is projected to be over 13 million by the end of the century. It is argued that policies to deconcentrate urban population will not be generally successful in Asia and that governments should attempt to manage the growth of large metropolitan areas more efficiently.

  • PDF