• 제목/요약/키워드: fragmented forest area

검색결과 32건 처리시간 0.026초

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

  • 이동근;이현이;김은영
    • 한국환경복원기술학회지
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    • 제10권6호
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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.

도시숲 조성 및 관리를 위한 도시숲 유형화 및 적용방안 (Classification of Urban Forest Types and its Application Methods for Forests Creation and Management)

  • 이동근;김은영;송원경;박찬;최혜영
    • 한국환경복원기술학회지
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    • 제12권5호
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    • pp.101-109
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    • 2009
  • There are increasing needs about creation and sustainable management of urban forest for environmental conservation and recreational service for citizen. However, it is difficult for local governments to create or manage urban forest in recreational or conservational way. The purpose of this study is to classify the urban forest types by considering its geographical feature, biological and sociological characteristics in order to suggest a guide to local governments about effective creation or management of urban forest. In this study, we extracted common characteristics of the selected five indicators. Factors about urban forest are divided into two groups. Factors were named according to the variables as 'Urban Forest Naturalness', and 'High Accessibility and Disturbed by Human.' In addition, we classified urban forests into four types in this study. The type I of urban forest is a large forest and has high naturalness such as Mt. Bukhan and Mt. Gwanak. The type II is fragmented to large forests by developmental projects. The type III is flat and has high accessibility such as forest behind Seonjeongneung. The type IV is located near residential area such as Mt. Ansan, Mt. Inwang and Mt. Bonghwa. It is possible to set up recreational area for citizens and ecological networks for species by the research of the urban forest type. The results of the study, classification of urban forest types and its application, contribute to provide a guide for local governments to create or manage urban forests effectively.

Consequences of land use change on bird distribution at Sakaerat Environmental Research Station

  • Trisurat, Yongyut;Duengkae, Prateep
    • Journal of Ecology and Environment
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    • 제34권2호
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    • pp.203-214
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    • 2011
  • The objectives of this research were to predict land-use/land-cover change at the Sakaerat Environmental Research Station (SERS) and to analyze its consequences on the distribution for Black-crested Bulbul (Pycnonotus melanicterus), which is a popular species for bird-watching activity. The Dyna-CLUE model was used to determine land-use allocation between 2008 and 2020 under two scenarios. Trend scenario was a continuation of recent land-use change (2002-2008), while the integrated land-use management scenario aimed to protect 45% of study area under intact forest, rehabilitated forest and reforestation for renewable energy. The maximum entropy model (Maxent), Geographic Information System (GIS) and FRAGSTATS package were used to predict bird occurrence and assess landscape fragmentation indices, respectively. The results revealed that parts of secondary growth, agriculture areas and dry dipterocarp forest close to road networks would be converted to other land use classes, especially eucalyptus plantation. Distance to dry evergreen forest, distance to secondary growth and distance to road were important factors for Black-crested Bulbul distribution because this species prefers to inhabit ecotones between dense forest and open woodland. The predicted for occurrence of Black-crested Bulbul in 2008 covers an area of 3,802 ha and relatively reduces to 3,342 ha in 2020 for trend scenario and to 3,627 ha for integrated-land use management scenario. However, intact habitats would be severely fragmented, which can be noticed by total habitat area, largest patch index and total core area indices, especially under the trend scenario. These consequences are likely to diminish the recreation and education values of the SERS to the public.

홍릉 숲의 곤충(개미와 지표성 딱정벌레)의 군집구조, 종다양성, 산림건강성 (Community Structure, Species Diversity of Insects (ants, ground beetles), and Forest Health in the Hongneung Forest)

  • 이철민;권태성
    • 한국산림과학회지
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    • 제102권1호
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    • pp.97-106
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    • 2013
  • 본 연구에서는 곤충군집의 특성을 이용하여 도시숲의 산림건강성 평가를 시도하였다. 이를 위해 서울도심에 위치한 홍릉 숲에서 함정트랩법으로 개미(Formicidae)와 지표성 딱정벌레(Carabidae)를 조사하여 광릉 숲의 그것과 비교하였다. 여기서 광릉 숲은 잘 보존되고 생물다양성과 자연성이 높기 때문에 산림건강성이 높을 것으로 추정하였다. 광릉 숲에 비해 홍릉 숲은 개미는 매우 많았으나, 딱정벌레는 매우 적었다. 종다양성의 경우에는 종풍부도는 광릉 숲이 높았으나, 종다양도는 홍릉 숲이 높았다. 광릉 숲에서는 소수의 숲 특이종에 의한 우점 현상이 심한데 비해, 홍릉 숲에서는 숲 특이종과 일반종이 균형을 이룸으로서 다양도가 광릉 숲에 비해 높았다. 이와 같이 홍릉 숲은 광릉 숲과는 곤충군집의 특성이 많이 달랐다.

통계모형을 활용한 박새류의 서식지 연결성 평가: 서울시 도시생태현황도 자료를 중심으로 (Habitat Connectivity Assessment of Tits Using a Statistical Modeling: Focused on Biotop Map of Seoul, South Korea)

  • 송원경;김은영;이동근
    • 환경영향평가
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    • 제22권3호
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    • pp.219-230
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    • 2013
  • Species distribution modeling is one of the most effective habitat analysis methods for wildlife conservation. This study was for evaluating the suitability of species distribution to distance between forest patches in Seoul city using tits. We analyzed the distribution of the four species of tits: varied tit (Parus varius), marsh tit (P. palustris), great tit (P. major) and coal tit (P. ater), using the landscape indexes and connectivity indexes, and compared the resulting suitability indexes from 100m to 1,000m. As factors affecting to the distribution of tits, we calculated landscape indices by separating them into intra-patch indices (i.e. logged patch area (PA), area-weighted mean patch shape index (PSI), tree rate (TR)) and inter-patch indices (i.e. patch degree (PD), patch betweenness (PB), difference probability of connectivity (DPC)), to analyze the internal properties of the patches and their connectivity by tits occurrence data using logistic regression modeling. The models were evaluated by AICc (Akaike Information Criteria with a correction for finite sample sizes) and AUC (Area Under Curve of ROC). The results of AICc and AUC showed DPC, PA, PSI, and TR were important factors of the habitat models for great tit and marsh tit at the level of distance 500~800m. In contrast, habitat models for coal tit and varied tit, which are known as forest interior species, reflected PA, PSI, and TR as intra-patch indices rather than connectivity. These mean that coal tit and varied tit are more likely to find a large circular forest patch than a small and long-shaped forest patch, which are higher rate of forest. Therefore, different strategies are required in order to enhance the habitats of the forest birds, tits, in a region that has fragmented forest patches such as Seoul city. It is important to manage forest interior areas for coal tit and varied tit, which are known as forest interior species and to manage not only forest interior areas but also connectivity of the forest patches in the threshold distance for great tit and marsh tit as adapted species to the urban ecosystem for sustainable ecosystem management.

Landscape Structure in the Greenbelt Zone around the Seoul, the Metropolis of Korea

  • Lee, Chang-Seok;Hong, Sun-Kee;Moon, Jeong-Suk;You, Young-Han
    • The Korean Journal of Ecology
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    • 제24권6호
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    • pp.385-394
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    • 2001
  • An attempt to clarify the landscape structure of urban areas was carried out in the greenbelt around Seoul, Korea's metropolis. By means of aerial photographs and a field survey, a vegetation map including land-use pattern was made. Landscape structure was described by analyzing this vegetation map and the results of phytosociological survey. Landscape element types identified were (1) secondary forest, (2) plantation, (3) cultivated field, (4) urbanized area, (5) graveyard, and (6) bare rock. Vegetation units, resulting from the phytosociological analysis, included Quercus mongolica, Q. variabilis, Q. acutissima, Pinus densiflora, Q. aliena, and Alnus japonica communities. Plantations were composed of Robinia pseudoacacia, Populus tomentiglandulosa, P. rigida, Larix leptolepis, P. koraiensis, and Castanea crenata stands. Patches near to human settlements in the lower zones of the mountains were fragmented and small but they became larger towards the higher mountain zones. On the other hand, the number of patches was fewer and their size was larger in Mt. Cheonggye more distant from the principal residential area, larger in size, and higher in elevation compared with the other 2 mountains, Mt. Daemo and Mt. Acha. Floristic composition of Mongolian oak(Q. mongolica) stand distributing in the upper part of each mountain, in which artificial interference is rare, showed a difference among those study areas different in parent rock and disturbance regime. But that of black locust(R. pseudoacacia) stand located in lowland of mountainous area, in which artificial interference is frequent was similar to each other. As the results of analyses on the frequency distribution of diameter classes of major species, dominant landscape elements, Mongolian oak forest showed different responses depending on artificial interference as continuous maintenance and retrogressive succession in the sites far from and near to the residential areas, respectively. On the other hand, black locust stands showed a probability to be restore to the native oak forest through progressive succession.

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지리산 국립공원 내 도로에 의한 산림조각화 (Forest Fragmentation Due to Roads in Chirisan National Park)

  • 백경진;박경;강혜순
    • 한국환경복원기술학회지
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    • 제8권1호
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    • pp.63-72
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    • 2005
  • Chirisan National Park, the first and largest one out of 20 national parks in Korea, is divided into five zones. They are composed of nature preservation zone, natural environment zone, natural residential zone, concentrated residential zone, and collective facility zone. However, the park is not a continuous habitat: roads, trails, local residences, and various facilities created the habitat mosaics severely fragmented. We investigated the fragmentation pattern of the park due to roads and mountain trails using GIS. Based on perimeter length, area, and the ratio of perimeter to area of each patch, we obtained landscape analysis indices which reflect the regularity of the patch shape. The 1 m-wide hiking trails divided the park into 491 fragments. The legal trails with 1.5 m - 3 m width which have been heavily used by hikers generate 58 fragments. Even the nature preservation zone, corresponding to a core zone comprising 31.8% of the park area, was divided into 37 fragments because of the roads and mountain trails. With the different widths of buffer applied, the core sizes of the fragments were reduced. When the 60 m buffer was applied, the patch interior areas ranged from 0.0001 to 47.77 $km^2$ with a mean of 7.08 $km^2$. The landscape shape indices were far greater than 1 for most of the cases with a maximum value of 25. These results clearly indicate that Chirisan National Park is not a continuous habitat, but mosaics of small, irregularly shaped habitat fragments. It is necessary to take the size and shape of the fragmented habitats into consideration when nature conservation is planned, especially for large wildlife such as brown bears.

경관투과성 및 최소비용경로 분석을 통한 수도권 지역의 광역생태축 구축 연구 (Regional Ecological Network Design for Wild Animals' Movement Using Landscape Permeability and Least-cost Path Methods in the Metropolitan Area of Korea)

  • 이동근;송원경;전성우
    • 한국환경복원기술학회지
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    • 제11권3호
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    • pp.94-106
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    • 2008
  • As populations inhabiting in natural ecosystem are fragmented by artificial barriers and habitats are destructed by development, extinction possibility of species is getting higher. It is necessary to design and to manage conservation areas and corridors considering animals' movement and migration for sustainable species diversity in present circumstances. 'Least-cost modeling' is one commonly employed approach in which dispersal costs are assigned to distinct habitat types and the last-costly dispersal paths among habitat patches are calculated using a geographical information system (GIS). This study aims to design ecological corridor using least-cost path method and to apply it to a regional ecological network considering movability of medium-large size mammals. This study was carried out over the metropolitan area, which has been deforested by rapid urbanization. Nevertheless there is connected with Gangwon province, Baekdudaegan mountain range and DMZ, considered where many forest species can migrate to this region. This study employs such an approach to develop least-cost path models for medium-large size mammals, have inhabited for this entire region. Considering those species, two forest areas as a source of species supply and forest areas more than 1,000ha are selected as focal forest areas. Movement and migration paths from species supply sources to focal forest areas are calculated by applying landscape permeability theory using land cover map, road density map and land slope map. Results showed least-cost paths from species supply sources to focal forest areas on two species. Wildcat and roe deer are different in some least-cost paths caused by their landscape permeability but paths show generally same specifics. The result of considering regional distribution of expected movement and migration paths to regional ecological network, low altitude mountains of western metropolitan area are evaluated important area for species connectivity. In national or regional levels ecological connectivity is essential to promote species diversity and to preserve integrated ecosystem. This study concludes that developing least-cost models from similar empirical data could significantly improve the utility of these tools.

Use of GIS to Develop a Multivariate Habitat Model for the Leopard Cat (Prionailurus bengalensis) in Mountainous Region of Korea

  • Rho, Paik-Ho
    • Journal of Ecology and Environment
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    • 제32권4호
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    • pp.229-236
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    • 2009
  • A habitat model was developed to delineate potential habitat of the leopard cat (Prionailurus bengalensis) in a mountainous region of Kangwon Province, Korea. Between 1997 and 2005, 224 leopard cat presence sites were recorded in the province in the Nationwide Survey on Natural Environments. Fifty percent of the sites were used to develop a habitat model, and the remaining sites were used to test the model. Fourteen environmental variables related to topographic features, water resources, vegetation and human disturbance were quantified for 112 of the leopard cat presence sites and an equal number of randomly selected sites. Statistical analyses (e.g., t-tests, and Pearson correlation analysis) showed that elevation, ridges, plains, % water cover, distance to water source, vegetated area, deciduous forest, coniferous forest, and distance to paved road differed significantly (P < 0.01) between presence and random sites. Stepwise logistic regression was used to develop a habitat model. Landform type (e.g., ridges vs. plains) is the major topographic factor affecting leopard cat presence. The species also appears to prefer deciduous forests and areas far from paved roads. The habitat map derived from the model correctly classified 93.75% of data from an independent sample of leopard cat presence sites, and the map at a regional scale showed that the cat's habitats are highly fragmented. Protection and restoration of connectivity of critical habitats should be implemented to preserve the leopard cat in mountainous regions of Korea.

산지 경계 추출을 위한 지형학적 변수 선정과 알고리즘 개발 (A Study on the Development of Topographical Variables and Algorithm for Mountain Classification)

  • 최정선;장효진;심우진;안유순;신혜섭;이승진;박수진
    • 한국지형학회지
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    • 제25권3호
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    • pp.1-18
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    • 2018
  • In Korea, 64% of the land is known as mountain area, but the definition and classification standard of mountain are not clear. Demand for utilization and development of mountain area is increasing. In this situation, the unclear definition and scope of the mountain area can lead to the destruction of the mountain and the increase of disasters due to indiscreet permission of forestland use conversion. Therefore, this study analyzed the variables and criteria that can extract the mountain boundaries through the questionnaire survey and the terrain analysis. We developed a mountain boundary extraction algorithm that can classify topographic mountain by using selected variables. As a result, 72.1% of the total land was analyzed as mountain area. For the three catchment areas with different mountain area ratio, we compared the results with the existing data such as forestland map and cadastral map. We confirmed the differences in boundary and distribution of mountain. In a catchment area with predominantly mountainous area, the algorithmbased mountain classification results were judged to be wider than the mountain or forest of the two maps. On the other hand, in the basin where the non-mountainous region predominated, algorithm-based results yielded a lower mountain area ratio than the other two maps. In the two maps, we was able to confirm the distribution of fragmented mountains. However, these areas were classified as non-mountain areas in algorithm-based results. We concluded that this result occurred because of the algorithm, so it is necessary to refine and elaborate the algorithm afterward. Nevertheless, this algorithm can analyze the topographic variables and the optimal value by watershed that can distinguish the mountain area. The results of this study are significant in that the mountain boundaries were extracted considering the characteristics of different mountain topography by region. This study will help establish policies for stable mountain management.