• Title/Summary/Keyword: Land cover

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The Influence of Land Cover and Zoning on the Urban Heat Island in Cheongju (도시내 용도지역의 토지피복형태가 열섬현상에 미치는 영향)

  • Cho, Sung-Moh;Yoon, Yong-Han;Ryu, Eul-Ryul;Park, Bong-Ju;Kim, Won-Tae
    • Journal of Environmental Science International
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    • v.18 no.2
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    • pp.169-176
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    • 2009
  • The present study observed temperature in order to identify factors affecting temperature by zoning and to measure the intensity of their impact on temperature. The empirical results of analyzing observed data are as follows. In order to make up for multicollinearity, a problem in multiple regression analysis, and to give more specific explanations, this study conducted factor analysis and obtained desirable data with adequacy and statistical significance. In the correlation matrix, factors decreasing temperature were planted areas, water surfaces and grasslands, and those increasing temperature were bare grounds, paved areas, and building area. According to land cover patterns, commercial areas had the highest temperature lowering effect. Through the rotated component matrix, we found that factors are grouped into those decreasing temperature, those increasing temperature, and those with low significance in increasing or decreasing temperature. In order to solve the problem of multicollinearity in multiple regression analysis, we performed factor analysis between the land use patterns and temperature and confirmed the usability of factor analysis as a new analysis method in urban heat island.

An Application of Canonical Correlation Analysis Technique to Land Cover Classification of LANDSAT Images

  • Lee, Jong-Hun;Park, Min-Ho;Kim, Yong-Il
    • ETRI Journal
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    • v.21 no.4
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    • pp.41-51
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    • 1999
  • This research is an attempt to obtain more accurate land cover information from LANDSAT images. Canonical correlation analysis, which has not been widely used in the image classification community, was applied to the classification of a LANDSAT images. It was found that it is easy to select training areas on the classification using canonical correlation analysis in comparison with the maximum likelihood classifier of $ERDAS^{(R)}$ software. In other words, the selected positions of training areas hardly affect the classification results using canonical correlation analysis. when the same training areas are used, the mapping accuracy of the canonical correlation classification results compared with the ground truth data is not lower than that of the maximum likelihood classifier. The kappa analysis for the canonical correlation classifier and the maximum likelihood classifier showed that the two methods are alike in classification accuracy. However, the canonical correlation classifier has better points than the maximum likelihood classifier in classification characteristics. Therefore, the classification using canonical correlation analysis applied in this research is effective for the extraction of land cover information from LANDSAT images and will be able to be put to practical use.

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Study of Urban Land Cover Changes Relative to Demographic and Residential Form Changes: A Case Study of Wonju City, Korea

  • Han, Gab-Soo;Kim, Mintai
    • Journal of Forest and Environmental Science
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    • v.31 no.4
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    • pp.288-296
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    • 2015
  • In many very high density cities in Asia in which there is limited area to expand, growth is forced upward as well as outward. Densely packed detached houses and low-rise buildings are replaced by lower density high-rises, leaving open spaces between high-rise buildings. Through this process, areas that formerly did not have much green space gain valuable green spaces, and new ecological corridors and patches are created. In this study, the demographic and housing-type changes of Wonju City were delineated using land use maps, aerial images, census data, and other administrative data. Green area changes were calculated using land cover data derived from multi-year Landsat TM satellite imagery. The values were then compared against demographic and housing-type changes for each administrative unit. The overall results showed a decrease of forested area in the city and an increase of developed area. Urban sprawl was clearly visible in many of the suburban areas. However, as expected, we also detected areas in which greenness did not decrease when the population greatly increased. These areas were characterized by residential building complexes of ten or more stories. If an equal number of housing units had been built as detached houses, these areas would not have kept as much green space. Our research result showed that high-density and high-rise residential structures can offer an alternative means to protect or create urban green spaces in high-density urban environments.

An Assessment of Urban Water Cycle in Changwon-si Using GIS-based Water Cycle Area Ratio (GIS 기반의 물순환 면적률을 활용한 창원시 도심지역의 물순환성 평가)

  • Song, Bonggeun;Park, Kyunghun;Lee, Taeksoon
    • Journal of Environmental Impact Assessment
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    • v.22 no.5
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    • pp.397-408
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    • 2013
  • The purpose of this study is to analyze water cycle area ratio and spatial evaluation of water cycle in urban area of Changwon-si, Gyeongsangnam-do. Water cycle area ratio are analyzed by using spatial data of land-cover and land-use, and Hot spot analysis of GIS program was used for spatial evaluation of water cycle. The results are as below. Firstly, the high water cycle area ratio areas were forests, parks, and rivers, but urban areas covered asphalt and concrete were low under 40%. Public institutions and co-residential of urban areas were higher than others because of high area ratio of pervious land-cover. Spatial evaluation of water cycle was analyzed to vulnerable areas there are dense residential and commercial area. These areas are really occurring frequently flooding and immersion, therefore, is required water management facilities and improvement of land-cover from impervious to pervious. In the future, it will require additionally analysis of water cycle area ratio supplemented data of water management facility and ground water.

Estimation of Carbon Sequestration in Urban Green Spaces Using Environmental Spatial Information - A case study of Ansan City- (환경공간정보를 활용한 도시녹지의 탄소흡수량 추정 -안산시를 대상으로-)

  • Kim, Sung-Hoon;Park, Eun-Jin;Kim, Il-Kwon
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.21 no.3
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    • pp.13-26
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    • 2018
  • This study estimated the carbon sequestration from urban green spaces in Ansan City using environmental spatial information. We examined study results of carbon sequestration from existing urban green spaces, using a land cover map (level 3). In particular, the carbon sequestration of trees by land use and the IPCC Global default value were linked with the land cover map level 3. Domestic research showed that carbon storage in urban green spaces in Ansan City was 17,927.2 tC, and the annual carbon sequestration was calculated as 2,680.5 tC/yr. On the other hand, applying the IPCC Global Default value resulted in annual carbon sequestration of 5,287.8 tC/yr, which was 2,607.3 tC/yr more that the domestic research value. This resulted from difference in detailed methodologies such as background data, sample size for on-site investigation, and measurement of tree species. The study presented a consistent assessment method to assess the sequestration of carbon from municipal urban green spaces. Furthermore, we provided basic data that could be useful in urban green space policies.

Analysis of Fragmentation and Heterogeneity of Tancheon Watershed by Land Development Projects (개발에 따른 탄천유역의 파편화 및 이질성분석)

  • Lee, Dong-Kun;Yi, Hyun-Yi;Kim, Eun-Young
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.10 no.6
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    • pp.120-129
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    • 2007
  • Rapid urbanization has transformed the spatial pattern of urban land use or cover. This paper concentrates that changed characteristics of landscape structure in the Tancheon Watershed, from 1995 to 2003 were investigated using land cover map. We used FRAGSTATS software to calculate landscape indices to characterize the landscape structure. We found that built up area has been increased rapidly during the study period, while cultivated area and forest area have been decreased rapidly in the same period. From 1995 to 2003, built up area was increased from 19.73% to 39.62% and cultivated area and forest area was decreased 17.60% to 5.97% and 58.31% to 49.41%. Number of patches, mean euclidean nearest-neighbor distance, contagion index, Shannon's diversity index increased considerably from 1995 to 2003, also suggesting the landscape in the study area became more fragmented and heterogeneous. but because of continuously fragmentation, landscape became homogeneity. The study demonstrates that landscape metrics can be a useful indicator in landscape monitoring and landscape assessment.

Assessment of Hydrological Impact by Long-Term Land Cover Changes due to Urbanization of Rural Area (농촌유역의 도시화 진전에 따른 수문환경 변화)

  • Lee, Mi-Seon;Park, Geun-Ae;Kwon, Hyung-Joong;Kim, Seong-Joon
    • Journal of Korean Society of Rural Planning
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    • v.11 no.1 s.26
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    • pp.17-24
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    • 2005
  • The purpose of this study is to evaluate the hydrological impact due to temporal land cover change by gradual urbanization of Anseong-cheon Gongdo watershed ($371.8km^2$). Land covers of 1981, 1990, 2000 Landsat TM images were classified by maximum likelihood method. The watershed showed a trend that forest & paddy areas decreased about $33km^2$ and $27km^2$, respectively and urban area increased about $11km^2$ during the periods. To identify the impact of streamflow due to urbanization, WMS HEC-1 was used. According to apply Huffs quartile storm events by changing land cover data, peak runoff discharge of each frequency rainfall (50, 100, 500 years) increased about 56, 36, $192m^3/sec$, respectively.

Land Use Characteristics in the Kyungan Watershed by Analyzing Long-Term Land Cover Data (장기적 토지피복 분석을 통한 경안천 유역의 토지이용 특성)

  • Han, Mideok;Kim, Jichan;Chung, Wookjin
    • Journal of Korean Society on Water Environment
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    • v.27 no.2
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    • pp.159-166
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    • 2011
  • The use of land cover was sharply changed during 1975~2007 in the Kyungan watershed $(561.12 km^2)$. The changes occurred over an area of more than $227.65 km^2$ during the overall period at changing rates of 1.04% per year for water area, 1.79% per year for residential area, 2.99% per year for bare area, 3.03% per year for wetland area, 3.04% per year for grass area, 0.87% per year for forest and 2.32% per year for agriculture area. Water, residential, bare and wetland areas increased, while grass, forest and agriculture areas decreased during the last 32 years. BOD concentrations of representative sites for each sub-watershed continuously increased until the early 2000s as residential area increased with the highest discharged load, but decreased after the mid 2000s except upper Kyungan watershed. Such decline appears to be associated with the planning of Total Maximum Daily Load management for Gwangju city and expansion of waste water treatment plant. It is necessary to control land use/cover changes of the upper watershed and to prepare appropriate watershed management system for improvement in river environment including water quality, stream flow and bio-diversity.

A Study of Factors Influencing of Temperature according to the Land Cover and Planting Structure in the City Park - A Case Study of Central Park in Bundang-gu, Seongnam - (도시공원의 토지피복 및 식재구조에 따른 온도 영향요인 규명 연구 - 성남시 분당구 중앙공원을 사례로 -)

  • Ki, Kyong-Seok;Han, Bong-Ho;Hur, Ji-Yeon
    • Korean Journal of Environment and Ecology
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    • v.26 no.5
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    • pp.801-811
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    • 2012
  • The purpose of this study is to find out how land cover and planting of an urban park influence temperature. Field research on the land cover and planting status was conducted for Bundang Central Park in Sungnam-si. 30 study plots in the site were selected to closely analyze land cover type and planting structure. The temperature was measured 10 times for each plot. Land coverage type, planting type, planting layer structure and green space area (the ratio of green coverage, GVZ) were chosen as factors impacting temperature and statistics were analyzed for the actual temperature measured. Analysis on how the land coverage type influences temperature showed that planting site had a low temperature and that grassland and paved land had a high temperature. When it comes to planting type, the temperature at the land planted with conifers and broad-leaved trees was low, while the temperature at grassland and paved land was high. With regard to planting layer structure, canopy and canopy-underplanting type showed low temperature, while grassland and paved land showed high temperature. An analysis on the relation between green space area and temperature found out that both ratio of green coverage and GVZ had a high level of negative correlation with the temperature measured. According to regression model of green space area and the temperature measured, for every 1% increase in the ratio of green coverage, temperature is expected to lower by $0.002^{\circ}C$. Also, for every $1m^3/m^2$ increase in GVZ, temperature is expected to go down by $0.122^{\circ}C$.

Analysis of Plant Height, Crop Cover, and Biomass of Forage Maize Grown on Reclaimed Land Using Unmanned Aerial Vehicle Technology

  • Dongho, Lee;Seunghwan, Go;Jonghwa, Park
    • Korean Journal of Remote Sensing
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    • v.39 no.1
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    • pp.47-63
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    • 2023
  • Unmanned aerial vehicle (UAV) and sensor technologies are rapidly developing and being usefully utilized for spatial information-based agricultural management and smart agriculture. Until now, there have been many difficulties in obtaining production information in a timely manner for large-scale agriculture on reclaimed land. However, smart agriculture that utilizes sensors, information technology, and UAV technology and can efficiently manage a large amount of farmland with a small number of people is expected to become more common in the near future. In this study, we evaluated the productivity of forage maize grown on reclaimed land using UAV and sensor-based technologies. This study compared the plant height, vegetation cover ratio, fresh biomass, and dry biomass of maize grown on general farmland and reclaimed land in South Korea. A biomass model was constructed based on plant height, cover ratio, and volume-based biomass using UAV-based images and Farm-Map, and related estimates were obtained. The fresh biomass was estimated with a very precise model (R2 =0.97, root mean square error [RMSE]=3.18 t/ha, normalized RMSE [nRMSE]=8.08%). The estimated dry biomass had a coefficient of determination of 0.86, an RMSE of 1.51 t/ha, and an nRMSE of 12.61%. The average plant height distribution for each field lot was about 0.91 m for reclaimed land and about 1.89 m for general farmland, which was analyzed to be a difference of about 48%. The average proportion of the maize fraction in each field lot was approximately 65% in reclaimed land and 94% in general farmland, showing a difference of about 29%. The average fresh biomass of each reclaimed land field lot was 10 t/ha, which was about 36% lower than that of general farmland (28.1 t/ha). The average dry biomass in each field lot was about 4.22 t/ha in reclaimed land and about 8 t/ha in general farmland, with the reclaimed land having approximately 53% of the dry biomass of the general farmland. Based on these results, UAV and sensor-based images confirmed that it is possible to accurately analyze agricultural information and crop growth conditions in a large area. It is expected that the technology and methods used in this study will be useful for implementing field-smart agriculture in large reclaimed areas.