• Korean Journal of Radiology
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• 제24권3호
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• pp.235-246
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• 2023

Objective: It is difficult to predict the treatment response of tissue after stereotactic radiosurgery (SRS) because radiation necrosis (RN) and tumor recurrence can coexist. Our study aimed to predict tumor recurrence, including the recurrence site, after SRS of brain metastasis by performing a longitudinal tumor habitat analysis. Materials and Methods: Two consecutive multiparametric MRI examinations were performed for 83 adults (mean age, 59.0 years; range, 27-82 years; 44 male and 39 female) with 103 SRS-treated brain metastases. Tumor habitats based on contrast-enhanced T1- and T2-weighted images (structural habitats) and those based on the apparent diffusion coefficient (ADC) and cerebral blood volume (CBV) images (physiological habitats) were defined using k-means voxel-wise clustering. The reference standard was based on the pathology or Response Assessment in Neuro-Oncologycriteria for brain metastases (RANO-BM). The association between parameters of single-time or longitudinal tumor habitat and the time to recurrence and the site of recurrence were evaluated using the Cox proportional hazards regression analysis and Dice similarity coefficient, respectively. Results: The mean interval between the two MRI examinations was 99 days. The longitudinal analysis showed that an increase in the hypovascular cellular habitat (low ADC and low CBV) was associated with the risk of recurrence (hazard ratio [HR], 2.68; 95% confidence interval [CI], 1.46-4.91; P = 0.001). During the single-time analysis, a solid low-enhancing habitat (low T2 and low contrast-enhanced T1 signal) was associated with the risk of recurrence (HR, 1.54; 95% CI, 1.01-2.35; P = 0.045). A hypovascular cellular habitat was indicative of the future recurrence site (Dice similarity coefficient = 0.423). Conclusion: After SRS of brain metastases, an increased hypovascular cellular habitat observed using a longitudinal MRI analysis was associated with the risk of recurrence (i.e., treatment resistance) and was indicative of recurrence site. A tumor habitat analysis may help guide future treatments for patients with brain metastases.

• 환경영향평가
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• 제13권1호
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• pp.21-31
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• 2004

Construction of highway would influence wildlife habitat being fragmented and deteriorated. It is inevitable to observe the death of animals that are killed by vehicles. Nonetheless the cause and status of animal roadkill have not been studied, and this study first attempted to analyze the roadkill in major highway in Korea. We collected 860 individuals of dead animals in Joongang Highway during 1996-2003. Among them Korean hare(Lepus sinensis) was totaled in 165 individuals(19.2%) with the highest figure; Korean racoon dog(Nyctereutes procyonoides) was 146(17.0%); Korean squirrel(Sciurus vulgaris) 56(6.5%); Korean roe deer(Capreolus capreolus) 26(3.0%). Domestic animals was totaled in 232 individuals(27.0%); domestic dog(Canis familiairis) 25, and domestic cat(Catus felis) 207. This study also categorized habitat as mountain-mountain, mountain-plain, mountain-river, plain-plain, plain-river, river-river in each side of the road. Habitat of mountain-plain was the heightest with 296(38.9%) individuals followed by mountain-mountain with 263(34.6%). This indicates that wild animals associated with mountain habitat was most influenced by the construction of roads. This study implied that we should mitigate the roadkill by designing artificial construction such as eco-bridge, fences along the sideway, and boxes under the highway, underdrain structure, etc. The monitoring and cause of habitat fragmentation with GIS approach should be followed to reduce the roadkill.

• 환경영향평가
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• 제17권2호
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• pp.133-141
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• 2008

The loss, alteration, and fragmentation of habitat have led to a reduction of biodiversity. The growing awareness of the negative effects of habitat fragmentation on natural systems has resulted in conservation strategy that is concerned with not only population and habitat level but also ecosystem and landscape level. Especially, ecological network to link core areas or major habitat patches is one of the most important issues. Recently, landscape connectivity is increasingly used in decision making for fragmented landscape management in order to conserve the biodiversity in the regional scale. The objective of this study was to find potential forest as a ecological corridor in Go-yang city, Gyung-gi province using cost-distance modelling method that can measure connectivity based on animal movement. 'Least cost-distance' modelling based on functional connectivity can be useful to establish ecological network and biodiversity conservation plan. This method calculates the distance modified with the cost to move between habitat patches based on detailed geographical information on the landscape as well as behavioural aspects of the animal movement. The least cost-distance models are based on two biologically assumptions: (1) dispersers have complete knowledge of their surroundings, and (2) they do select the least cost route from this information. As a result of this study, we can find wildlife moving route for biodiversity conservation. The result is very useful for long-term aspect of biodiversity conservation plan in regional scale, because this is reflection of geographical information and behavioural aspects of the animal movement.

• 한국수자원학회논문집
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• 제42권6호
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• pp.481-491
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• 2009

금강수계중 용담댐하류 앞섬 지점에서 생태유량을 산정하기 위한 생태 모니터링을 실시하여 어류종별 서식환경 특성조사를 포괄적으로 실시하였다. 이를 바탕으로 어류상, 상대풍부도 및 생물다양도 분석 등을 포함한 하천의 건강성 평가를 실시하고, 쉬리, 피라미 및 감돌고기 등에 대하여 작성한 서식처적합도 지수(HSI)와 물리적 서식처 모의시스템(PHABSIM)을 이용한 최적 생태유량을 산정하였다. 본 지점에서 채집된 종수는 20종이였으며, 우점종은 쉬리(22.4%), 아우점종은 피라미(22.0%)였다. 생태적 건강성은 50점 만점의 평가점수에서 $34{\sim}42$점으로 양호에서 좋은 상태로 나타났다. 3종의 대표어종에 대한 수심, 유속 및 하상재료에 대한 서식지적합도 지수를 물리적서식처 모의시스템에 적용한 결과 계절별로 유량의 차이를 보였으며, 3종에 대한 최적 생태유량은 9.0 cms로 추정하였다.

• 한국환경복원기술학회지
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• 제18권2호
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• pp.19-32
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• 2015

In Korea, significant riparian areas have been developed due to river maintenance projects. Introduction of new riparian facilities can negatively affect wildlife in the riparian areas. This study focuses on selecting core conservation areas for Eurasian Otter(Lutra lutra) to support decision making process for development of riparian areas. For the study, first of all, field data of study site were collected by field surveys. Secondly, stream naturalness was assessed to understand physical environments of the study sites. Thirdly, habitat suitability was assessed using occurrence data of Eurasian Otter and environmental data. Lastly, core areas for conservation was selected by comparing and synthesizing stream naturalness map and habitat suitability map. The selected core areas showed several characteristics. The number of artificial facilities is low in the core areas. Rocks which are preferred by Eurasian Otter to eat and excrete are plentiful in the core areas. Also, the ratio of adjacent farmland is high. Based on the analyses, it is expected that this study can contribute to decision making process for environmental spatial plans to better conserve habitats of Eurasian Otter.

• 환경영향평가
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• 제26권6호
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• pp.385-403
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• 2017

본 연구는 국내 생태분야 리스크 평가 및 적응대책 수립의 공간적 기준이 될 수 있는 생태계 유형분류방안 검토를 목적으로 하였다. 이를 위해, 생태분야 기후변화 리스크 평가와 적응대책의 특징, 국내외 리스크 평가에서 적용하는 생태계/서식지 유형분류 현황 및 관련 데이터를 조사하였다. 영국을 비롯하여 유럽 등지에서 일반적으로 생물종다양성 및 생태계서비스 평가를 위한 공간정보DB로 토지피복분류가 널리 활용되고 있음에 착안하여, 국내 토지피복분류의 적용성을 정량적으로 검토하였다. 그 결과, 기후변화 리스크 평가 및 적응대책 수립을 위한 생태계 유형분류 시 현재 국내 대분류 토지피복 체계만으로는 분류군별 서식 경향성을 거의 알 수 없기에 대분류를 그대로 적용하는 것은 한계가 있을 것으로 생각된다. 우리나라 국토 피복 전반을 차지하는 산림 생태계(62.3%) 및 농경지 생태계(25.0%) 유형의 세분화와 함께, 국토대비 면적은 작지만 다양한 분류군이 서식하는 습지생태계(2.9%), 특수 분류군이 서식하는 연안(0.4%) 및 해양생태계(0.6%), 도시생태계(6.1%)에 대한 분류가 고려되어야 한다. 추후 산림, 농경지 피복분류에 있어 중분류 체계 이하의 세분화가 필요하며, 국토 대비 면적에 비해 분류군의 서식지 선호비율이 높은 내륙습지, 해양/해안 서식지, 도시와 자연생태계의 전이지역 등에 대한 반영 역시 필요할 것으로 생각된다.

• 농촌계획
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• 제20권4호
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• pp.13-24
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• 2014

The pond wetlands in agricultural landscape are important natural resources that carry out the function of bio-diversity conservation. However, recently, those have been gradually embedded as their utility value were disappeared. And, the assessment methods used for pond wetlands are insufficient. Therefore, this study was conducted to examine the conservation value of pond wetlands by using the modified RAM, and present the improvement of assesment methods. The study sites, a total of 32 pond of 4 types by land use, were selected on the basis of Ramsar Convention. Through the analysis of precedent studies, the weighted 8 functions were adjusted. According to the assessment results, pond wetlands made the largest contribution to Fishery and Herpetile Habitat function. In addition, it also made large contribution to Floral Diversity, Wildlife Habitat, and Water Quality Protection function. On the other hand, it made a small contribution to Aesthetics and Recreation, Runoff Attenuation, Shoreline /Stream Bank Protection, and Flood/Storm Water Storage function due to the characteristics of small-scale pond wetlands. In the assessment of 8 functions, house type showed the worst assessment result, and mountain type showed the best assessment result. It is thought that those are due to land use type in terms of vicinity. 10 items among 52 of the modified RAM showed the same assessment results in all land use types. Accordingly, it is required to be deleted and modified the assessment method. On the other hand, it is required to add age, interference, and water use to the assessment method. It is thought that these results can be utilized for the development and modification of assessment methods focused on pond wetlands in rural area.

• Spatial Information Research
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• 제8권1호
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• pp.85-99
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• 2000

보호동물사에 대한 서식지 분포정보는 개발압력이 심한 우리나라에서는 서식지 관리에 있어 매우 중요하다. 본 연구는 GIS와 로지스틱 회귀분석을 이용하여 멧돼지의 서식지 적합성모형을 개발하여 서식지 분포도를 작성하고 본 연구의 결과를 토대로 현재 우리나라의 멸종위기종과 야생동물보호종들의 서식지 관리를 위한 기초를 마련하고자한다. 서식지 모형을 구현하기 위한 연구내용 및 방법은 다음과 같다. 첫째, 멧돼지의 서식지 특성을 파악하기 위하여 GIS 자료를 구축하였다. 멧돼지의 위치파악을 위해 원격무선측정기법과 GPS를 이용하였다 둘째, 멧돼지의 서식지 이용과 유용성에 영향을 미치는 환경인자를 파악하기위해 원격무선측정기법과 GPS를 이용하였다. 둘째, 멧돼지의 서식지 이용과 유용성에 영향을 미치는 환경인자를 파악하기 위해 χ²검정(Chi-square test)을 실시하였다. 마지막으로, 최적 서식지의 분포를 예측하기위한 서식지 적합성모형 개발을 위해 로지스틱 회귀분석을 이용하였다. 본 연구의 결과는 다음과 같다. 첫째, 멧돼지의 서식지 이용특성 분석의 결과, 성별 그리고 활동유형별에서는 뚜렷한 차이를 볼 수 없으나, 계절별 그리고 서식지 유형별에서는 서식지 이용특성의 차이가 뚜렷한 것을 볼 수있었다. 둘째, 서식지 유용성 분석의 결과 멧돼지의 서식환경에 영향을 미치는 자연적인 환경요인으로 표고, 향, 임상 그리고 영급이 유의성이 있는 인자로 나타났다. 반면에, 경사, 능선/계곡 , 물 그리고 일사량의 경우 통계적 유의성이 적어 전반적으로 서식지를 결정하는 환경인자라고 볼 수 없었다. 마지막으로, 개발된 서식지 적합성모형의 결과 예측확률 0.5를 기준으로 전제서식지는 75.00%, 커버서식지는 84.26% 의 높은 분류정확도를 나타내었다. 모형검증의 결과 대상지 내부의 경우 전체서식지가 75.00%로 나타나 본 모형이 신뢰성이 있는 것으로 판단되었다.

• 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.

• 한국환경생태학회지
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• 제26권3호
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• pp.322-332
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• 2012

본 연구는 원격무선추적 자료를 바탕으로 우리나라의 농촌지역에 서식하는 삵의 행동권, 서식지 선택, 개체군 위협요인을 파악하고자 하였으며 3개체(수컷 2, 암컷 1)를 대상으로 한 연구결과는 다음과 같다. 첫째, 행동권은 평균 $2.64{\pm}1.99km^2$(K 95)와 $3.69{\pm}1.34km^2$(MCP 100)이었으며, 핵심공간은 평균 $0.64{\pm}0.47km^2$(K 50)를 나타냈고, 겨울철에 추적된 수컷의 행동권이 가장 넓었다($5.19km^2$, MCP 100). 둘째, Jacobs index에 기반을 둔 Johnson의 서식지 선택모형을 분석한 결과 삵은 2단계 선택(경관 내에서의 서식지 선택)에서 초지와 논을 선호하고 산림은 회피하는 반면에, 3단계 선택(행동권 내에서의 서식지 선택)에서는 하천변의 초지를 매우 선호하고 논을 회피하였다. 셋째, 로드킬은 삵의 심각한 개체군 위협요인으로 판단되며, 논의 토지피복 비율이 높고, 하천변에 도로가 존재하며, 산림이 마을 주위에만 소규모로 존재하는 지역에서는 삵의 개체군 유지가 매우 불안정할 수 있어 이러한 지역에 로드킬 대책과 하천변 초지보호 등의 노력이 보다 집중되어야 할 것이다.