• Title/Summary/Keyword: Land Cover changes

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HYDROLOGIC IMPACT ASSESSMENT OF LAND COVER CHANGES BY 2002 TYPHOON RUSA USING LANDSAT IMAGES AND STORM RUNOFF MODEL

  • Lee, Mi-Seon;Park, Geun-Ae;Kim, Seong-Joon
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.539-542
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    • 2006
  • To investigate the streamflow impact of land cover changes by a typhoon, WMS HEC-1 storm runoff model was applied by using land cover information before and after the typhoon. The model was calibrated with three storm events of 1985 to 1988 based on 1985 land cover condition for a 192.7 $km^2$ watershed in northeast coast of South Korea. After the model was tested, it was run to estimate impacts of land cover change by the typhoon RUSA occurred in 2002 (31 August - 1 September) with 897.5 mm rainfall. The land covers before and after the typhoon were prepared using Landsat 7 ETM+ of September 11 of 2000 and Landsat 5 TM of September 29 of 2002 respectively. For the 6.9 $km^2$ damaged area (3.6 % of the watershed), the peak runoff and total runoff by the changed land cover condition increased 12.5 % and 12.7 % for 50 years rainfall frequency and 1.4 % and 1.8 % for 500 years rainfall frequency respectively based on AMC (Antecedent Moisture Condition)-I condition.

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Hydrologic Impact Assessment of land Cover Changes by 2002 Typhoon RUSA Using Landsat Images and Storm Runoff Model

  • Lee, Mi-Seon;Park, Geun-Ae;Kim, Seong-Joon
    • Korean Journal of Remote Sensing
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    • v.22 no.5
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    • pp.407-413
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    • 2006
  • To investigate the streamflow impact of land cover changes by a typhoon, HEC-l storm runoff model was applied by using land cover information before and after the typhoon. The model was calibrated with three storm events of 1985 to 1988 based on 1985 land cover condition for a $192.7km^{2}$ watershed in northeast coast of South Korea. After the model was tested, it was run to estimate impacts of land cover change by the typhoon RUSA occurred in 2002 (31 August-1 September) with 897.5 mm rainfall. The land covers before and after the typhoon were prepared using Landsat 7 ETM+ of September 11 of 2000 and Landsat 5 TM of September 29 of 2002 respectively. For the $6.9km^{2}$ damaged area (3.6 % of the watershed), the peak runoff and total runoff by the changed land cover condition increased 12.5 % and 12.7 % for 50 years rainfall frequency and 1.4 % and 1.8 % for 500 years rainfall frequency respectively based on AMC (Antecedent Moisture Condition)-I condition.

Class Knowledge-oriented Automatic Land Use and Land Cover Change Detection

  • Jixian, Zhang;Yu, Zeng;Guijun, Yang
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.47-49
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    • 2003
  • Automatic land use and land cover change (LUCC) detection via remotely sensed imagery has a wide application in the area of LUCC research, nature resource and environment monitoring and protection. Under the condition that one time (T1) data is existed land use and land cover maps, and another time (T2) data is remotely sensed imagery, how to detect change automatically is still an unresolved issue. This paper developed a land use and land cover class knowledge guided method for automatic change detection under this situation. Firstly, the land use and land cover map in T1 and remote sensing images in T2 were registered and superimposed precisely. Secondly, the remotely sensed knowledge database of all land use and land cover classes was constructed based on the unchanged parcels in T1 map. Thirdly, guided by T1 land use and land cover map, feature statistics for each parcel or pixel in RS images were extracted. Finally, land use and land cover changes were found and the change class was recognized through the automatic matching between the knowledge database of remote sensing information of land use & land cover classes and the extracted statistics in that parcel or pixel. Experimental results and some actual applications show the efficiency of this method.

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Assessment of Hydrological Impact by Tracing Long-term Land Cover Changes Using Landsat TM Imageries

  • Kim, Seong J.;Park, Geun A.
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.50-52
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    • 2003
  • The purpose of this study is to evaluate the hydrological impact due to temporal land cover changes by gradual urbanization of a watershed. WMS HEC-1 was adopted, and DEM with 200m resolution and hydrologic soil group from 1:50,000 soil map were prepared. Land covers of 1986, 1990, 1994 and 1999 Landsat TM images were classified by maximum likelihood method. By applying the model, watershed average CN value was affected in the order of paddy, forest and urban/residential, respectively.

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Impacts of the High Resolution Land Cover Data on the 1989 East-Asian Summer Monsoon Circulation in a Regional Climate Model (지역기후모델에서 고해상도 지면피복이 1989년 동아시아 여름몬순 순환에 미치는 영향)

  • Suh, Myoung-Seok;Lee, Dong-Kyou
    • Atmosphere
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    • v.15 no.2
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    • pp.75-90
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    • 2005
  • This study examines the impacts of land cover changes on the East Asia summer monsoon with the National Center for Atmospheric Research Regional Climate Model (NCAR RegCM2), coupled with Biosphere Atmosphere Transfer Scheme (BATS). To assess the goals, two types of land cover maps were used in the simulation of summer climate. One type was NCAR land cover map (CTL) and the other was current land cover map derived from satellite data (land cover: LCV). Warm and cold surface temperature biases of $1-3^{\circ}C$ occurred over central China and Mongolia in CTL. The model produced excessive precipitation over northern land area but less over southern ocean of the model domain. Changes of biophysical parameters, such as albedo, minimum stomatal resistance and roughness length, due to the land cover changes resulted in the alteration of land-atmosphere interactions. Latent heat flux and wind speed in LCV increased noticeably over central China where deciduous broad leaf trees have been replaced by mixed farm and irrigated crop. As a result, the systematic warm biases over central China were greatly reduced in LCV. Strong cooling of central China decreased pressure gradient between East Asian continent and Pacific Ocean. The decreased pressure gradient suppressed the northward transport of moisture from south China and South China Sea. These changes reduced not only the excessive precipitation over north China and Mongolia but also less precipitation over south China. However, the land cover changes increased the precipitation over the Korean Peninsula and the Japan Islands, especially in July and August.

The Land Cover Changes at the Small Watersheds Using the Multi-temporal Satelite Images (다시기 위성영상을 이용한 소유역의 토지피복변화 평가)

  • Kang, Moon-Seong;Park, Seung-Woo
    • Journal of Korean Society of Rural Planning
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    • v.6 no.2 s.12
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    • pp.50-58
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    • 2000
  • The purposes of the study were to detect and evaluate the historical land use and land cover changes on the Balan watersheds from three thematic mapper (TM) data, which were taken in 1985, 1993, and 1996. The supervised and unsupervised classification methods were adopted to classify five land cover categories: Paddy, upland, forest, residential, and water. The results indicated residential areas increased significantly during the past eleven years, Forest and paddy were converted to the urban areas. Future land cover patterns were forecasted using a Markov chain method, and the simulated land coiler change ratios presented.

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Prediction of Land-cover Change in the Gongju Areas using Fuzzy Logic and Geo-spatial Information (퍼지 논리와 지리공간정보를 이용한 공주지역 토지피복 변화 예측)

  • Jang, Dong-Ho
    • Journal of Environmental Impact Assessment
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    • v.14 no.6
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    • pp.387-402
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    • 2005
  • In this study, we tried to predict the change of future land-cover and relationships between land-cover change and geo-spatial information in the Gongju area by using fuzzy logic operation. Quantitative evaluation of prediction models was carried out using a prediction rate curve using. Based on the analysis of correlations between the geo-spatial information and land-cover change, the class with the highest correlation was extracted. Fuzzy operations were used to predict land-cover change and determine the land-cover prediction maps that were the most suitable. It was predicted that in urban areas, the urban expansion of old and new towns would occur centering on the Gem-river, and that urbanization of areas along the interchange and national roads would also expand. Among agricultural areas, areas adjacent to national roads connected to small tributaries of the Gem-river and neighboring areas would likely experience changes. Most of the forest areas are located in southeast and from this result we can guess why the wide chestnut-tree cultivation complex is located in these areas and the possibility of forest damage is very high. As a result of validation using the prediction rate curve, it was indicated that among fuzzy operators, the maximum fuzzy operator was the most suitable for analyzing land-cover change in urban and agricultural areas. Other fuzzy operators resulted in the similar prediction capabilities. However, in the prediction rate curve of integrated models for land-cover prediction in the forest areas, most fuzzy operators resulted in poorer prediction capabilities. Thus, it is necessary to apply new thematic maps or prediction models in connection with the effective prediction of changes in the forest areas.

Synergic Effect of using the Optical and Radar Image Data for the Land Cover Classification in Coastal Region

  • Kim, Sun-Hwa;Lee, Kyu-Sung
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1030-1032
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    • 2003
  • This study a imed to analyze the effect of combined optical and radar image for the land cover classification in coastal region. The study area, Gyeonggi Bay area has one of the largest tidal ranges and has frequent land cover changes due to the several reclamations and rather intensive land uses. Ten land cover types were classified using several datasets of combining Landsat ETM+ and RADARSAT imagery. The synergic effects of the merged datasets were analyzed by both visual interpretation and an ordinary supervised classification. The merged optical and SAR datasets provided better discrimination among the land cover classes in the coastal area. The overall classification accuracy of merged datasets was improved to 86.5% as compared to 78% accuracy of using ETM+ only.

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The Spatial-temporal Changes of the Land use/cover in the Dongting lake Area of Central China during the Last Decade

  • Rendong, Li;Hongzhi, Wang;Dafang, Zhuang
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.417-419
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    • 2003
  • Based on the Chinese resource and environment database, and using the Landsat TM and ETM data acquired in 1990 and 2000 respectively, the spatial-temporal characteristics of land use/cover changes in the Dongting lake area of central China was analyzed. The result showed that cultivated land decreased by 0.57% of total cultivated land. Built -up land and water area expanded, with an increase of 8.97% and 0.43% respectively. 94 percent of the cropland decreased was changed into water (mostly to fishpond) and built-up areas. Land-use changed most quickly in cities, and the slowest in the north and east of the study area.

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Structural Urban Landscape Changes over Time Series in Gangneung-Si (강릉시 도시 경관 구조의 시계열적 변화 연구)

  • Yeum, Jung-Hun
    • Journal of Environmental Science International
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    • v.30 no.10
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    • pp.779-787
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    • 2021
  • This study analyzes structural landscape changes over a time-series for a small and medium-sized city, Gangneung-Si, based on area and distribution patterns, and according to the type of land cover. Among the types of land cover, the area ratio of urbanized areas increased by 2.02% in the late 2010s as compared to the late 1980s, while there was a decrease of 2.69% in farmland and 0.69% in grassland areas. On analyzing the changes in land cover use by applying the Fragstats program, it was confirmed that landscape changes in urban and management areas were relatively severe according to the Landscape Shape Index, Largest Patch Index, and Aggregation Index. A pattern of concentrated expansion was also found around certain areas. In particular, from the analysis, it was established that the proportion of urbanized area had considerably increased and that the extent of farmland damage to management areas, including planned management areas, was large. Additionally, the Total Core Area generally indicated a reduction in the core areas of farmland and forest within urban and management areas. A medium-sized city showed significant changes besides large cities in terms of landscape structure. The developmental pressure on management areas, in particular, was quite high.