• Journal of Ecology and Environment
• /
• 제32권4호
• /
• pp.229-236
• /
• 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.

• 대한치과의사협회지
• /
• 제48권4호
• /
• pp.275-279
• /
• 2010

Dental implant restoration in partial or full edentulous state has become the standard treatment in recent years. Bone graft with guided bone regeneration technique has been regarded as one of the most reliable methods to restore the bone defect area due to periodontal disease or dental trauma. Bone graft materials and membrane are the essential component of guided bone regeneration; however, a variety of bone graft materials confuse us in implant dentistry. Autogenous bone is the recognized standards in implant dentistry owing to its osteogenesis potential. Despite of its disadvantages, grafting autogenous bone is the most reliable methods. Even though the development of new bone grafts materials, autogenous bone is useful in exposed implant thread and total lack of buccal or lingual bone. Allogenic, xenogenic and synthetic bone have the osteoconductive and osteoinductive potential. These materials could be used successfully in self-contained cavity such as sinus cavity and three-wall defects. In this article, application of bone graft material is suggested according to the function of bone graft materials.

• 한국환경복원기술학회지
• /
• 제9권6호
• /
• pp.63-77
• /
• 2006

The research aim is to classify biotope types of rural eco-villages designed by ministry of environment and analyze landscape ecological characteristics of them. This information would provide information on eco-villages' potential and specific needs to improve landscape ecological structure of eco-villages. Two eco-villages, designated by ministry of environment, in Yoocheon-ri and Sanduk-ri were selected and the landscape ecological metrics used in this study were Area, Shannon diversity index, Shape index, Distance index. The results are as follows. 1) There were five biotope types in large-scale classification, 13 biotope types m Sanduk-ri and 9 biotope types in Yoocheon-ri in middle-scale classification, 31 biotope types in Sanduk-ri and 24 biotope types in Yoocheon-ri in small-scale classification. 2) In the case of area, artificial biotope types, such as artificial forest, agricultural irrigation canal, wet paddy, dry paddy and residential area, covered more than 80% of total area. However, natural biotope types, such as natural forest, river, reservoir, covered just more than 10% of total area. In details, an orchard (26.69%) was the dominant biotope type, followed by artificial forest (19.10%) in Sanduk-ri and the first most abundant biotope type was artificial forest (49.71%), followed by wet paddy (15.95%) in Yoocheon-ri. 3) The result of Shannon diversity index indicated that Sanduk-ri (2.158) had more heterogeneity landscape, rather than Yoocheon-ri (2.051). 4) In the case of shape index, road (13.09) had more complex and irregular shape than either agricultural irrigation canal (3.35) or artificial forest (2.46) in Sanduk-ri. Road (6.52) was also the most irregular biotope shape, followed by river (5.70) and agricultural irrigation canal (4.78) in Yoocheon-ri. 5) Mean Nearest-neighbour Distance (MND) was smallest in wet paddy and dry paddy biotope types in the two study area, suggesting that these biotope types were concentrated within these study areas. From the result, this research suggested information to protect and improve biotopes of eco-villages in the landscape ecological terms. To achieve this improvement plan, there should be strong support by ministry of environment and local governments.

• 대한원격탐사학회지
• /
• 제35권4호
• /
• pp.517-534
• /
• 2019

In abrupt fire disturbances, high quality images suitable for wildfire damage assessment can be difficult to acquire. Quantifying wildfire burn area and severity are essential measures for quick short-term disaster response and efficient long-term disaster restoration. Planetscope (PS) imagery offers 3 m spatial and daily temporal resolution, which can overcome the spatio-temporal resolution tradeoff of conventional satellites, albeit at the cost of spectral resolution. This study investigated the potential of augmenting PS imagery by integrating the spectral information from Sentinel-2 (S2) differenced Normalized Burn Ratio (dNBR) to PS differenced Normalized Difference Vegetation Index (dNDVI) using histogram matching,specifically for wildfire burn area and severity assessment of the Okgye wildfire which occurred on April 4th, 2019. Due to the difficulty in acquiring reference data, the results of the study were compared to the wildfire burn area reported by Ministry of the Interior and Safety. The burn area estimates from this study demonstrated that the histogram-matched (HM) PS dNDVI image produced more accurate burn area estimates and more descriptive burn severity intervals in contrast to conventional methods using S2. The HM PS dNDVI image returned an error of only 0.691% whereas the S2 dNDVI and dNBR images overestimated the wildfire burn area by 5.32% and 106%, respectively. These improvements using PS were largely due to the higher spatial resolution, allowing for the detection of sparsely distributed patches of land and narrow roads, which were indistinguishable using S2 dNBR. In addition, the integration of spectral information from S2 in the PS image resolved saturation effects in areas of low and high burn severity.

• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 2001년도 총회 및 춘계학술발표회
• /
• pp.19-21
• /
• 2001

The Shiheung mine was closed in 1972 and has been abandoned since then. Although some restoration work has been done, there still remain mine failings in and around the mine, posing a potential environmental hazard. Mine tailings and the porewater extracted from the tailing were investigated to see any evidence of elemental release and migration to adjacent groundwater and soil in the field. The pHs of the tailing range from 6.24 to 7.23. Calcite in the studied area seems to influence on such neutral pH range. Depth profile of mine tailing demonstrate elements have been leached and removed as a consequence of weathering during disposal. This is also supported by the findings from porewater analysis, corresponding the trends in the mine tailings. The concentrations of Cu, Cd, Pb, Zn in the tailing porewater exceed the standard value of EPA for drinking water and this implies groundwater can be contaminated through infiltration of the porewaters, which ultimately will be discharged as leachate from the mine tailing. Groundwater samples collected near the mine area do not show high metal concentrations, except for Fe, which were detected over drinking water standard.

• Spatial Information Research
• /
• 제15권2호
• /
• pp.147-158
• /
• 2007

강원도 지역은 매년 다양한 재해를 반복적으로 겪고 있으며 이러한 재해는 이 지역의 지속적인 발전에 장애요인이 되고 있다. 특히 2002년 태풍 루사에 의한 집중호우는 막대한 피해와 더불어 우리사회의 많은 교훈을 남겼다. 지역방재계획에는 강우사상에 따른 피난계획이 수립되어 있으나 실제 상황에서는 그 역할을 기대할 수 없었다. 또한 재해복구에 있어서도 원상복구에 그치고 있어 재해에 대한 잠재적 가능성을 그대로 남아 있는 실정이다. 따라서 본 연구에서는 유역의 개발이 수문 유출에 미치는 영향에 대해 종합적으로 고찰하고자 한다.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2018년도 학술발표회
• /
• pp.442-442
• /
• 2018

강의 하도와 연결되어 간헐적으로 침수되는 홍수터는 가장 생산적인 육역 서식처 중 하나이다. 하지만 도시 개발과 농업이용은 강의 하도와 홍수터와의 연결을 제한함으로써 그 기능이 상당부분 축소되었다. 이에 기존 홍수터 서식처를 특성화하고 미래 홍수터 복원을 계획하는 것은 하천관리 및 생태계 회복을 위해서도 매우 중요하다고 할 수 있다. 따라서 본 연구에서는 홍수 흐름의 규모, 시기, 기간, 빈도 등을 포함한 하천 유황 특성과 생태적 반응이 나타나는 홍수터 영역과 흐름 특성을 연계함으로써 서식처를 정량화 하고자 하였다. 이를 위한 홍수터 복원의 시나리오는 현재 지형(기존 홍수터), 제방후퇴, 제방후퇴/구하도 복원, 제방후퇴/배후습지 조성으로 설정하였다. 홍수터 서식처를 정량화하기 위한 방법으로는 일 유량의 수문통계학적 분석, 수리학적 모델링을 통한 범람 분석, 어류 물리서식처 모델링을 통한 가중가용면적 분석 등을 수행하였다. 그 결과 잠재복원영역(Potential Restored Area)에서 연중 기대되는 서식처 면적(Expected Annual Habitat Area)의 크기는 제방후퇴/배후습지 조성, 제방후퇴/구하도 복원, 제방후퇴, 기존 홍수터 순으로 나타났다. 본 연구에서 제안된 홍수터 복원에 따른 서식처 정량화 방안은 홍수터 복원 계획 설계 시 시나리오 별 서식처 복원효과를 예측 평가함으로써 보다 효과적인 방안을 마련할 수 있을 것으로 기대된다.

• 한국조경학회지
• /
• 제42권1호
• /
• pp.123-132
• /
• 2014

이 연구의 목적은 수변 생태벨트를 조성, 보전, 관리를 위해 수변생태벨트의 진단적 평가방법을 개발하는 것이었다. 평가의 기본 틀은 일본의 제방림 평가방법을 토대로 하였으며, 국내 수변녹지의 현황에 맞게 수정한 1차 수정평가방법으로 1차 시험평가를 실시하였다. 1차 시험평가의 문제점을 보완한 2차 수정안을 가지고 전문가를 대상으로 설문을 실시하고, 그 결과를 반영하여 최종 평가방법을 제안하였다. 최종 평가방법으로 홍천강에서 시험평가를 실시하였다. 최종적으로 제안된 평가방법의 평가영역은 5가지 분야 19가지 항목으로 구성되었으며, 5가지 분야는 치수, 환경기능, 식물생장, 생태벨트기능, 복원잠재성 등이다. 치수분야 평가항목은 수림의 길이, 폭, 밀도 등 3가지 항목으로, 환경기능분야는 공원이용, 경관 경계 및 주연부, 미기후 조절, 비점오염 제어 등 4가지 항목으로, 식물생장분야는 종 구성, 수림 높이, 계층구조, 덩굴식물, 식물활력도, 후계목 생장 등 6가지 항목으로, 생태벨트기능 분야는 종적 연결성, 횡적 연결성, 하천내 수림 혹은 서식지, 제방상단 도로 등 4가지 항목으로, 마지막으로 복원잠재력분야는 지형, 인접 토지이용 등 2가지 항목으로 구성되었다. 점수체계는 1~4까지 부여되었으며, 최종 평가결과 등급체계는 우수한 1등급에서 가장 열악한 5등급까지 5등급으로 구분하였다. 각 분야별 항목별 가중치는 동일하게 하였으며, 분야별 점수 평균값을 다시 평균하여 최종 등급을 판정하는 것으로 하였다. 홍천강을 대상으로 적용된 평가방법은 각 구간의 수변 생태벨트 실태를 효과적으로 보여주었다.

• 한국환경생태학회지
• /
• 제22권5호
• /
• pp.564-594
• /
• 2008

현재잠재자연하천의 식생을 연구하기 위하여 인간의 영향을 받은 흔적이 없는 또는 거의 없는 국내의 자연하천구역 25개소를 다양한 환경요소를 고려하여 선정하고, 2006년과 2007년 여름에 식생조사를 실시하였다. 조사는 Braun-Blanquet(1964)에 의거 1개 조사구(하천연장 약 1km)에 5개의 방형구와 Belt-transect에 따른 횡단면(길이 20m)의 좌우안의 4개의 belt/ 1개 조사구에서의 출현식물을 조사하였다. 그 결과 위도 $37^{\circ}{\sim}37.9^{\circ}$의 중북부지방 조사구 하천에서의 공통적 식물군락은 신갈나무군락과 신갈나무와 갈참나무를 동반한 물푸레나무군락이었고, 위도 $35^{\circ}{\sim}35.9^{\circ}$의 남부지방 조사구하천에서는 졸참나무, 때죽나무, 굴참나무군락, 위도 $36^{\circ}{\sim}36.9^{\circ}$의 중부지방은 중북부와 남부의 중간적 특성을 보인 졸참나무, 물푸레나무, 갈참나무군락으로 조사되었다. 그리고 조사구하천의 환경요인과 출현식생과의 상관성을 분석한 결과 Eco region이 가장 높은 상관성을 보였으나, 앞으로 다양한 환경인자를 고려한 사례조사구의 증가를 통하여 하천유형별 잠재자연하천의 식생을 규명하는 것이 홍수터복원계획에 절실할 것으로 사료된다.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2011년도 학술발표회
• /
• pp.46-46
• /
• 2011

Severe sediment erosion during floods occur disaster and economic losses, but general sediment erosion is basic mechanism to move sediment from upstream to downstream river. In addition, it is important process to change river form. Check dam, which is constructed in mountain stream, play a vital role such as control of sudden debris flow, but it has negative aspects to river ecosystem. Now a day, check dam of open type is an alternative plan to recover river biological diversity and ecosystem through sediment transport while maintaining the function of disaster control. The purpose of this paper is to verify sediment erosion progress of river bottom and bank as first step for river restoration after dam slit by cross-sectional shear stress and critical shear stress. Study area is upstream reach of slit check dam in mountain stream, named Wasada, in Japan. The check dam was slit with two passages in August, 2010. The transects were surveyed for four upstream cross-sections, 7.4 m, 34 m, 86 m, and 150 m distance from dam in October 2010. Sediment size was surveyed at river bottom and bank. Sediment of cobble size was found at the wetted bottom, and small size particles of sand to medium gravel composed river bank. Discharge was $2.5\;m^3/s$ and bottom slope was 0.027 m/m. Excess shear stress (${\tau}_{ex}$) was calculated for hydraulic erosion by subtracting the values of critical shear stress (${\tau}_{c}$) from the value of shear stress (${\tau}$) at river bottom and bank (${\tau}_{ex}=\tau-{\tau}_c$). Shear stress of river bottom (${\tau}_{bottom}$) was calculated using the cross-sectional shear stress, and bank shear stress (${\tau}_{bank}$) was calculated from the method of Flintham and Carling (1988). $${\tau}_{bank}={\tau}^*SF_{bank}((B+P_{bed})/(2^*P_{bank}))$$ where $SF_{bank}=1.77(P_{bed}/p_{bank}+1.5)^{-1.4}$, B is the water surface width, $P_{bed}$ and $P_{bank}$ are wetted parameter of the bed and bank. Estimated values for ${\tau}_{bottom}$ for a flow of $2.5\;m^3/s$ were lower as 25.0 (7.5 m cross-section), 25.7 (34 m), 21.3 (86 m) and 19.8 (150 m), in N/$m^2$, than critical shear stress (${\tau}_c=62.1\;N/m^2$) with cobble of 64 mm. The values were insufficient to erode cobble sediment. In contrast, even if the values of ${\tau}_{bank}$ were lower than the values for ${\tau}_{bottom}$ as 18.7 (7.5 m), 19.3 (34 m), 16.1 (86 m) and 14.7 (150 m), in N/$m^2$, excess shear stresses were calculated at the three cross-sections of 7.5 m, 34 m, and 86 m distances compare with ${\tau}_c$ is 15.5 N/$m^2$ of 16mm gravel. Bank shear stresses were sufficient for erosion of the medium gravel to sand. Therefore there is potential to erode lateral bank than downward erosion in a flow of $2.5\;m^3/s$. Undercutting of the wetted bank can causes bank scour or collapse, therefore this channel has potential to become wider at the same time. This research is about a potential of sediment erosion, and the result could not verify with real data. Therefore it need next step for verification. In addition an erosion mechanism for river restoration is not simple because discharge distribution is variable by snow-melting or rainy season, and a function for disaster control will recover by big precipitation event. Therefore it needs to consider the relationship between continuous discharge change and sediment erosion.