• 제목/요약/키워드: Land Coverage

검색결과 226건 처리시간 0.029초

지표피복변화 연구에서 최적의 공간스케일의 문제 : 가나 북부지역의 사바나 지역을 사례로 (Optimal Spatial Scale for Land Use Change Modelling : A Case Study in a Savanna Landscape in Northern Ghana)

  • 닉반드기슨;폴플렉;박수진
    • 대한지리학회지
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    • 제40권2호
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    • pp.221-241
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    • 2005
  • 토지이용 및 지표피복변화 (Land Use and land Cover Changes, LUCC)는 지구환경변화의 원인으로 중요한 연구대상이 되고 있다. LUCC는 복잡한 사회적, 경제적, 정치적 상호작용속에서 다양한 시$\cdot$공간적 스케일에서 발생하게 된다. 따라서 LUCC를 모델화하기 위해서는 LUCC를 야기시키는 원인(driving forces)과 제한요인(constraints)들의 시$\cdot$공간적인 다양성을 이해하는 작업이 선행되어야 한다. 특히, 특정 지역에서 나타나는 LUCC의 동인을 파악하기 위해서는 스케일에 따른 그 특성의 변화를 이해하는 것이 급선무이다. 이 연구는 가나(Ghana) 북부지역의 사바나 지역을 대상으로 지난 15년간 나타난 지표피복변화의 공간적인 다양성을 파악한 뒤, 공간적 스케일을 달리하면서 나타나는 LUCC의 원인을 분석하였다. 이 과정을 통해 사바나 지역에서 LUCC 과정을 모형화하기 위한 최적의 공간적인 스케일을 규명하고자 하였다. 연구지역은 지난 15년간 인구증가의 결과로 농업생산활동이 급격하게 증가한 지역이다. 연구지역에서 나타나는 지표피복변화의 정도는 LANDSAT 위성영상에서 추출한 NDVI들을 다변량 통계분석기법을 이용하여 정량화하였다. 그리고 지표피복변화의 원인을 스케일별로 파악하기 위한 도구로 다축척 계층분석기법(multi-scale hierarchical adaptive model)을 개발$\cdot$제안하였다. 개발된 기법은 지표피복의 변화정도와 원인이 될 수 있는 공간변수들간의 상관성을 공간적인 스케일을 달리하면서 순차적으로 계산해낼 수 있는 기법이다. 이 연구에서 지표피복변화의 원인으로는 '도로에서부터의 거리', 하천으로부터의 거리', '지형특성' 의 세가지 변수를 사용하였다. 지표피복 변화정도와 위의 세가지 변수들간의 상관관계는 공간적인 범위가 10$\times$10km 이하인 경우에 높게 나타났다. 하지만 공간범위가 그 이상이 될 경우에는 그 내부에서 나타나는 다양성으로 인해 통계적인 상관성이 현격하게 낮아지는 것을 관찰할 수 있었다. 이러한 결과는 지역 및 국가 단위의 환경변화모델에서 모델의 공간적인 구성범위가 일정한 수준을 넘으면, 그 내부에서 발생하고 있는 다양성이 급격하게 증가하여 지표피복변화의 원인과 결과를 정확하게 파악하기 힘들게 된다는 것을 의미한다. 10$\times$10km의 공간적인 범위는 농업생산이 위주가 되는 사바나 지역에서는 주로 개별 마을이 차지하고 있는 공간적인 범위와 대체적으로 일치한다. 따라서 사바나 지역에서 나타나는 지표피복변화의 다양성을 고려하면서 보다 정확하게 모형화하기 위해서는 마을단위에서 나타나는 지표피복변화과정이 최소의 모델단위가 되어야 함을 시사한다.

한강하구에 도래하는 재두루미(Grus vipio) 서식지이용과 토지피복도 상관관계 연구 (Comparison of White-naped Crane Habitat Use Pattern with Land-coverage Map in the Han-River Estuary and DMZ)

  • 김성옥;이상돈
    • 환경영향평가
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    • 제17권4호
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    • pp.255-262
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    • 2008
  • For the Han-river estuary and DMZ where white-naped crane (Grus vipio; endangered migratory bird) stopover or spend winter, the habitat composition and the habitat use pattern of white-naped crane were analyzed with the position data obtained by the satellite tracking method. By the use of geographic information system (GIS), the percent composition of seven habitat categories of white naped-crane data points (n=228) was analyzed. The chi-square test showed that the white-naped crane habitat use pattern was significantly different (p<0.05) from that of random points (n=228). It means that white-naped crane select and use particular habitat area in the Han-river estuary and DMZ.

녹지분포에 따른 기온변화 (Air Temperature Variation by Effect of Green Space Distribution)

  • 윤용한
    • 한국환경복원기술학회지
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    • 제5권2호
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    • pp.47-52
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    • 2002
  • In this study, in order to find out relationship of green space distribution and lower air temperature effect, observed air temperature distribution in and out green space in the cloudy. On basis of the result, we are analyzed relationship of air temperature distribution in and out green space, of green space distribution and air temperature of, lower air temperature effect and the urban in between the green space by using regression analysis. According to the result, the higher temperature zone formed around urban, and the lower temperature zone was similar to shape of green space. In case of the green space, higher temperature zone is formed around paved surface and barren ground, lower temperature zone is done forest and water area. To compare air temperature of windward and leeward around green space, the windward formed the lower temperature zone and although the wind direction is not the leeward to the green space, air temperature formed lower temperature zone to the urban in between the green space.

사막화방지(沙漠化防止) 및 방사기술개발(防沙技術開發)에 관한 연구(硏究)(II) - 중국(中國)의 경관(景觀)-생태(生態) 방호림조성기술(防護林造成技術) 및 효과분석(效果分析) - (Studies on the Desertification and Sand Industry Development(II) - Analysis of Silvicultural Techniques and Effects of Landscape-Eco Shelterbelt Establishment -)

  • 우보명;이경준;전기성;김경훈;최형태;이승현;이병권;김소연;이상호;전정일
    • 한국환경복원기술학회지
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    • 제3권3호
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    • pp.81-99
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    • 2000
  • The shelterbelts are very important to conserve and protect the sandy land, vegetation coverage, farmland, livestock and human life in the desertified land. The shelterbelts are constructed by the several row-plantings of high-adaptable species in the desertified land. The shelterbelts have various kind of type, and there are shelterbelts for conservation of farmland in dry the region, the protective shelterbelts (windbreaks for blowing-sand, artificial sanddune fixation by revegetation, and construction of farmland shelterbelts to protect farmland and pasture from wind erosion, etc.) in the semi-dry steppe, shelterbelts around the villages and oasis for sanddune fixation, shelterbelts for protection of railroads, and so on. The shelterbelts consist of main she1terbelts and minor shelterbelts. The main shelterbelts were constructed by being perpendicular to main wind direction, and the minor shelterbelts were constructed by being perpendicular to the main shelterbelts. Generally, the width of shelterbelts is 8~20m, and the number of row-planting is 4~10. The grid sizes of shelterbelts networks are $400{\times}400m$, $300{\times}500m$, $100{\times}200m$, and so on, and there are ventilation type and closing type in the type of shelterbelt. The width, number of row-planting, grid size and type of shelterbelt are selected by the local characteristics. The effects of shelterbelts are mainly the climate improvement and mitigation, such as prevention of occurrence of strong wind, cold wind and blowing-sand. And, the other effects of shelterbelts are effect of reforestation, increase of agricultural productions, establishment of greenbelts and green forests, construction of landscape-eco shelterbelts, improvement of life environment of local villages, supply of fuel wood and agricultural wood, land amelioration, effect of revegetation and restoration of desertified land, and so on. The kinds of the tree species mainly used for the construction of shelterbelts have differences between regions, but main species are Populus euphratica, Populus simonii, Populus bolleana, Populus tomentosa, Salix flavida, Salix mongolica, Tamarix chinensis, Hedysarum scoparium, and so on.

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A Rule-based Urban Image Classification System for Time Series Landsat Data

  • Lee, Jin-A;Lee, Sung-Soon;Chi, Kwang-Hoon
    • 대한원격탐사학회지
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    • 제27권6호
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    • pp.637-651
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    • 2011
  • This study presents a rule-based urban image classification method for time series analysis of changes in the vicinity of Asan-si and Cheonan-si in Chungcheongnam-do, using Landsat satellite images (1991-2006). The area has been highly developed through the relocation of industrial facilities, land development, construction of a high-speed railroad, and an extension of the subway. To determine the yearly changing pattern of the urban area, eleven classes were made depending on the trend of development. An algorithm was generalized for the rules to be applied as an unsupervised classification, without the need of training area. The analysis results show that the urban zone of the research area has increased by about 1.53 times, and each correlation graph confirmed the distribution of the Built Up Index (BUI) values for each class. To evaluate the rule-based classification, coverage and accuracy were assessed. When Optimal allowable factor=0.36, the coverage of the rule was 98.4%, and for the test using ground data from 1991 to 2006, overall accuracy was 99.49%. It was confirmed that the method suggested to determine the maximum allowable factor correlates to the accuracy test results using ground data. Among the multiple images, available data was used as best as possible and classification accuracy could be improved since optimal classification to suit objectives was possible. The rule-based urban image classification method is expected to be applied to time series image analyses such as thematic mapping for urban development, urban development, and monitoring of environmental changes.

Low-Earth orbit satellite constellation for ADS-B based in-flight aircraft tracking

  • Nguyen, Thien H.;Tsafnat, Naomi;Cetin, Ediz;Osborne, Barnaby;Dixon, Thomas F.
    • Advances in aircraft and spacecraft science
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    • 제2권1호
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    • pp.95-108
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    • 2015
  • Automatic Dependent Surveillance Broadcast (ADS-B) is quickly being adopted by aviation safety authorities around the world as the standard for aircraft tracking. The technology provides the opportunity for live tracking of aircraft positions within range of an ADS-B receiver stations. Currently these receiver stations are bound by land and local infrastructural constraints. As such there is little to no coverage over oceans and poles, over which many commercial flights routinely travel. A low cost space based ADS-B receiving system is proposed as a constellation of small satellites. The possibility for a link between aircraft and satellite is dependent primarily on proximity. Calculating the likelihood of a link between two moving targets when considering with the non-periodic and non-uniform nature of actual aircraft flight-paths is non-trivial. This analysis of the link likelihood and the performance of the tracking ability of the satellite constellation has been carried out by a direct simulation of satellites and aircraft. Parameters defining the constellation (satellite numbers, orbit size and shape, orbit configuration) were varied between reasonable limits. The recent MH370 disappearance was simulated and potential tracking and coverage was analysed using an example constellation. The trend of more satellites at a higher altitude inclined at 60 degrees was found to be the optimal solution.

발생부하원단위와 수치표고모형을 이용한 하천유역 오염부하량 산정 (Calculation of Pollutant Loadings from Stream Watershed Using Digital Elevation Model and Pollutant Load Unit Factors)

  • 양홍모;김혁
    • 한국조경학회지
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    • 제29권1호
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    • pp.22-31
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    • 2001
  • The purpose of this study is to compare calculated pollutant loadings using pollutant load unit factors and vector type coverage, and expected mean concentration(EMC) and raster type of digital elevation model(DEM). This study is also focusing on comparison of the advantages and the disadvantages of the two methods, and seeking for a method of calculation of pollutant loadings using DEM. Estimation of pollutant inputs using pollutant load unit factors has limitations in identifying seasonal variations of pollutant loadings. Seasonal changes of runoffs should be considered in the calculation of pollutant loadings from catchments into reservoirs. Evaluation of pollutant inputs using runoff-coefficient and EMC can overcome these drawbacks. Proper EMC and runoff-coefficient values for the Koeup stream catchments of the Koheung estuarine lake were drawn from review of related papers. Arc/Info was employed to establish database of spatial and attribute data of point and non-point pollutant sources and characteristics of the catchments. ArcView was used to calculate point and non-point pollutant loadings. Pollutant loads estimated with either unit factors-coverages, i.e., pollutant load unit factors and vector coverages f point sources and land use, or EMC and digital elevation mode(DEM) were compared with stream monitoring loads. We have found that some differences were shown between monitoring results and estimated loads by Unit Factors-Coverage and EMC-DEM. Monthly variations of pollutant loads evaluated with EMC-DEM were similar to those with monitoring result. The method using EMC-DEM can calculate accumulated flows and pollutant loads and can be utilized to identify stream networks. A future research on correcting the difference between vector type stream using flow direction grid and digitalizing vector type should be conducted in order to obtain more exact calculation of pollutant loadings.

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경기도의 옥상녹화 가용면적 추정과 이의 정책적 함의 (Estimation of the Potential Area for Roof Greening in Gyeonggi-do and Its Implications)

  • 박은진;남미아;강규이
    • 한국환경복원기술학회지
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    • 제15권1호
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    • pp.107-117
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    • 2012
  • We estimated the potential area roof greening in Gyeonggi-do that will mitigate the heat island effect. The estimation was based on building age, roof shape, and building use which were recorded in the building register from "Sewoomteo, the Building Administration System in the Ministry of Land, Transport and Maritime Affairs. The estimated potential roof greening area in Gyeonggi-do was approximately $102.5km^2$ assuming that the buildings for residence, public, education(school), office, shopping mall are appropriate for roof greening. The area occupied by apartment buildings over six-story was 76.3% of the potential roof greening area 10.2% for individual houses, 5.9% for under five-story apartment buildings, and 3.7% for school buildings. The result indicated that it is residential buildings that we need to pay attention for roof greening, especially high-rise buildings over six-story. Greening of the whole estimated area, $102.5km^2$, in Gyeonggi-do will result in the increase of green space per capita by $8.74m^2$. This is 1.65 times greater than the area of current urban parks, and 1.97 times greater than the total area of neighborhood parks, children's parks, and pocket parks. Greening of the estimated roof area will increase green coverage of urban area by twice, adding to current green coverage of the urban areas, 11.3%, in 10 major cities. In particular, the effect of roof greening would be remarkable in inceasing the green space of Anyang City, Gwangmyeong City, and Guri City where neighborhood park area falls short.

Maxent 모델을 이용한 호박벌과 양봉꿀벌의 수분 잠재환경 비교 분석 - 서울시를 중심으로 - (A Comparative Analysis on the Pollination Potential Environment of Apis millifera and Bombus ignitus Using the Maxent Model - Focused on Seoul -)

  • 김윤호;조용현;배양섭;김태종;손인기
    • 한국환경복원기술학회지
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    • 제24권1호
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    • pp.25-36
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    • 2021
  • The honey bee has a crucial ecological status for maintaining the natural ecology system. Pollination mediations by honey bees are recognized as an efficient way to enhance the quality of biological diversity and green areas in the nature and the urban ecological system. However, the population of bee around the world is decreasing and we do not know exactly how bees react to the physical environment in the urban area. This study is a basic research for the improvement of pollination services in the Korean urban ecological system. It aims to induce and review environmental variables which have high relations with the activities of pollination mediation insects in the urban area. The study established a Maxent model using five urban environmental variables that reflect the ecology of Bombus ignitus and the place information where Bombus ignitus appears in 18 spots of Seoul city, and compared with previous research results on Apis millifera. Bombus ignitus preferred places with more natural environments such as mountain forest areas and vicinities of streams. They preferred Stratified Tree Area the most among the vegetation types existing in the urban area. Comparing chicken models, both species saw their response value drop as the building coverage rose. In the case of Apis millifera and Bombus ignitus variables, the response value of both species was high in 10 out of 20 types. The result of this study is expected to provide basic information for improving the pollination services in the Korean urban area and to be utilized as the basic materials for the future urban planning.

GIS를 활용한 생태면적률 산정 모델 개발 (Development of Biotope area ratio Estimation Model using GIS)

  • 이지수;이승욱;이승엽;홍원화
    • Spatial Information Research
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    • 제19권2호
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    • pp.9-18
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    • 2011
  • 본 연구의 목적은 신도시 등의 조성에 있어 지속 가능한 발전을 도모하고 시민들에게 쾌적한 생활환경을 제공하기 위해 도입된 생태면적률을 산정하는 모델을 개발하여 구축의 효율성과 데이터베이스 유지관리의 간편성과 정확성을 확보함에 있다. 특히 생태면적률은 현재 환경영향 평가 뿐만 아니라 친환경 인증기준 중 생태환경기준으로 활용되고 있으나, 생태면적률의 산정도 구축을 위한 지표가 제시되어 있지 않기 때문에 결과자료의 누락, 데이터 수정보완의 어려움과 같은 문제가 있을 수 있다. 따라서 본 연구에서는 GIS를 통해 도형 자료를 구축하고 가중치의 속성정보를 통합하여 관리하는 모델을 제시하였다. 생태면적률 산정은 토지이용계획도를 기초로 하여 건폐지의 경우 옥상 및 벽면 녹화, 비건폐지의 경우 수공간, 인공지반, 틈새투수포장, 자연지반 녹지의 공간유형을 대상으로 한다. 가중치가 부여된 공간유형정보는 도형정보와 통합되고 통합된 자료는 향후 토지이용에 따른 분석을 위해 토지이용계획 정보를 블록 별로 부여한다. 한편, 공간유형별 가중치 적용의 경우 도출방법이 각 지자체나 적용 주체의 상황에 따라 특성에 맞게 판단기준의 조절이 가능하다. 따라서 그 수치가 유동적일 수 있으나 본 모델에서 수치변화에 대한 탄력적인 대응이 가능함으로써 간편하고 효율적인 데이터 구축의 모델로 활용될 수 있다.