• 제목/요약/키워드: Natural caves

검색결과 50건 처리시간 0.034초

도로와 교차하는 제주천연동굴(재암천굴)의 거동특성 분석을 위한 수치해석적 연구 (Numerical Analysis Study for Behavioral Characteristics Analysis of Jeju Natural Caves (Jaeamcheon Lava Tube) That Intersect with Roads)

  • 이종현;진현식;안준상;백용
    • 지질공학
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    • 제31권3호
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    • pp.367-380
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    • 2021
  • 본 연구는 제주도 내 운영중인 도로하부에 천연동굴이 존재하는 경우, 3차원 수치해석적 방법을 통해 안정성을 평가하였다. 도로 하부를 관통하는 제주천연동굴의 기하학적 및 지반공학적 특성을 확인하기 위해 기존 지반조사보고서를 수집한 후, 그 특성을 검토하였다. 이를 토대로 차량진동하중이 제주천연동굴에 미치는 영향을 평가하기 위하여 불연속면을 고려한 3차원 수치해석을 실시하였다. 연구결과를 토대로, 차량속도, 토피고에 따른 도로와 제주천연동굴의 안정성을 평가하고, 대책을 제안하였다. 도로 하부를 관통하는 제주천연동굴의 장기안정성 확보를 위하여, 토피고에 따라 장기계측관리, 보강대책, 응급대책 등 체계적인 관리가 필요할 것으로 평가되었다.

A study on Bilogical Environment of Ondal Cave

  • Kim, Chu-Yun;Yoo, Yeong-Jun
    • 동굴
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    • 제4호
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    • pp.11-21
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    • 1996
  • Ondal cave is the limestone and the cultural asset cave designated as Natural monument NO. 261. Originally after the caves included in cultural assets separately survey the academic, cultural value of the cave, the result must be the academic basis of the cave.(omitted)

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Yellow-colored mats in Jeju Island lava tubes

  • Kim, Jong-Shik;Kim, Dae-Shin;Lee, Keun Chul;Kim, Yong-Hwan;Ahn, Ung-San;Lee, Mi-Kyung;Lee, Jung-Sook
    • 한국응용과학기술학회지
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    • 제36권4호
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    • pp.1338-1348
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    • 2019
  • The Geomunoreum Lava Tube System, declared as a UNESCO World Heritage Site, has a unique natural ecosystem. The information available about this ecosystem, which contains lava caves with secondary carbonate speleothems, is sparse. Hence, extensive research is warranted for establishing a conservation standard. We commenced microbial research on the system and have been studying the microorganisms coating the lava tube wall to acquire fundamental information for understanding the lava cave ecology of Jeju Island. Samples were collected from yellow-colored walls in six caves that are part of the system-the Bengdwi, Utsanjeon, Bukoreum, Manjang, Gimnyeong, and Yongcheon caves. This study focused on yellow walls as it is the most easily distinguished color. According to previous studies, the color of cave walls is attributed to microorganisms or their components. To determine whether the yellow mats from the Jeju lava tube walls are caused by microorganisms, we examined samples at the microscopic scale, by staining mats and analyzing bacterial isolates from glitter particles. As a result, we found that the yellow walls of lava tubes are comprised of microbial mats.

Identification of Martian Cave Skylights Using the Temperature Change During Day and Night

  • Jung, Jongil;Yi, Yu;Kim, Eojin
    • Journal of Astronomy and Space Sciences
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    • 제31권2호
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    • pp.141-144
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    • 2014
  • Recently, cave candidates have been discovered on other planets besides the Earth, such as the Moon and Mars. When we go to other planets, caves could be possible human habitats providing natural protection from cosmic threats. In this study, seven cave candidates have been found on Pavonis Mons and Ascraeus Mons in Tharsis Montes on Mars. The cave candidates were selected using the images of the Context Camera (CTX) on the Mars Reconnaissance Orbiter (MRO). The Context Camera could provide images with the high resolution of 6 meter per pixel. The diameter of the candidates ranges from 50 to 100m. Cushing et al. (2007) have analyzed the temperature change at daytime and nighttime using the Thermal Emission Imaging System (THEMIS) for the sites of potential cave candidates. Similarly, we have examined the temperature change at daytime and at nighttime for seven cave candidates using the method of Cushing et al. (2007). Among those, only one candidate showed a distinct temperature change. However, we cannot verify a cave based on the temperature change only and further study is required for the improvement of this method to identify caves more clearly.

전문가 설문을 통한 제주특별자치도 환경자원 가중치 분석에 관한 연구 (A Study on Weight Analysis of Environmental Resources in Jeju Special Self-Governing Province through Expert Survey)

  • 서정영
    • 한국환경과학회지
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    • 제32권11호
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    • pp.767-775
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    • 2023
  • This study was conducted to lay the foundation for considering the qualitative aspects of environmental resources by calculating the weight of each environmental resource to calculate the total amount of environmental resources in Jeju. By comparing and analyzing the results of the expert survey conducted in 2011 and the results of the expert survey conducted in 2011 and 2022, changes in experts' perceptions and implications over time were derived. In addition, based on the results of the recent survey, the weight according to the relative importance was calculated to lay the foundation for calculating the total amount of environmental resources in Jeju. The results of this study are expected to provide basic data necessary for the successful institutionalization of the total environmental resource system by providing a scientific basis for the calculation of the total environmental resource. As a result of comparing the survey conducted in 2011 to the survey conducted in 2022 to establish a total environmental resource management plan in Jeju Special Self-Governing Province, there was a difference in the relative importance of the environmental resource category. Although the ranking between categories did not change, it was confirmed that the relative importance of the natural and local resource environment decreased and the relative importance of the living environment field increased significantly. Over time, the importance of plants and wildlife increased, the importance of landscapes and topographic geology decreased, the importance of wetlands and caves increased, and the importance of Gotjawal, natural monuments, and cultural history decreased. In the living environment category, the importance of water pollution increased significantly, and in the humanities and social environment category, the importance of population increased and the importance of industry decreased. It is judged that most changes in item importance are largely influenced by changes in the background of the times and overall perception. It was confirmed that the importance of plants, wildlife, wetlands, and caves with relatively high awareness and the importance of water pollution, which is emerging as a regional problem, have all increased significantly due to structural problems of population age.

Landscapes and Ecosystems of Tropical Limestone: Case Study of the Cat Ba Islands, Vietnam

  • Van, Quan Nguyen;Duc, Thanh Tran;Van, Huy Dinh
    • Journal of Ecology and Environment
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    • 제33권1호
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    • pp.23-36
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    • 2010
  • The Cat Ba Islands in Hai Phong City, northern Vietnam, consist of a large limestone island with a maximum height of 322 m above sea level and 366 small limestone islets with a total area of about $180\;km^2$. The islands are relicts of karst limestone mountains that became submerged during the Holocene transgression 7000 - 8000 year ago. The combination of the longtime karst process and recent marine processes in the monsoonal tropical zone has created a very diversity landscape on the Cat Ba Islands that can be divided into 3 habitat types with 16 forms. The first habitat type is the karst mountains and hills, including karst mountains and hills, karst valleys and dolines, karst lakes, karst caves, and old marine terraces. The second habitat type is the limestone island coast, including beaches, mangrove marshes, tidal flats, rocky coasts, marine notch caves, marine karst lakes, and bights. The third habitat type is karst plains submerged by the sea, including karst cones (fengcong) and towers (fengling), bedrock exposed on the seabed, sandy mud seabed, and submerged channels. Like the landscape, the biodiversity is also high in ecosystems composed of scrub cover - bare hills, rainy tropical forests, paddy fields and gardens, swamps, caves, beaches, mangrove forests, tidal flats, rocky coasts, marine krast lakes, coral reefs, hard bottoms, seagrass beds and soft bottoms. The ecosystems on the Cat Ba Islands that support very high species biodiversity include tropical evergreen rainforests, soft bottoms; coral reefs, mangrove forests, and marine karst lakes. A total of 2,380 species have been recorded in the Cat Ba Islands, included 741 species of terrestrial plants; 282 species of terrestrial animals; 30 species of mangrove plants; 287 species of phytoplankton; 79 species of seaweed; 79 species of zooplankton; 196 species of marine fishes; 154 species of corals; and 538 species of zoobenthos. Many of these species are listed in the Red Book of Vietnam as endangered species, included the white-headed or Cat Ba langur (Trachypithecus poliocephalus), a famous endemic species. Human activities have resulted in significantly changes to the landscape end ecosytems of the Cat Ba islands; however, many natural aspects of the islandsd have been preserved. For this reason, the Cat Ba Islands were recognized as a Biological Reserved Area by UNESCO in 2004.

제주도 토양 방선균의 속 다양성 분포

  • 권오성;박동진;이찬용;김창진
    • 한국미생물·생명공학회지
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    • 제24권4호
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    • pp.399-403
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    • 1996
  • Total 938 actinomycete strains were isolated from 59 soil samples collected at Cheju island. All of these isolates were identified to the genus level based on morphological and physiological characteristics. As the result, 62.6% of those isolates were Streptomyces, 16.4% were Micromonospora, 8.6% were Nocardioform group, 2.2% were Actinomadura, 1.7% were Microbispora, 1.6% were Nocardiopsis, 1.0% were Streptosporangium, and 5.9% were the others. As the sources of soil, Streptomyces and Microbispora were abundant in grassland soil, Streptomyces and Micromonospora were abundant in field soil, and Micromonospora were abundant in forest soil. Especially, Nocardioform strains were abundant in natural caves.

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요녕성 본계지역 자연동굴 탐사기 (A Study on Natural Cave developed at Bongye Area in Liaoning Province)

  • 김정희
    • 동굴
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    • 제67호
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    • pp.73-79
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    • 2005
  • 우리들이 속해있는 동북아시아 지역에서 한반도가 이어진 대륙의 깊숙한 곳, 중국 요녕성 본계지역과 환인지역의 동굴탐사를 바탕으로 이 지역 주변의 문화와 환경을 살펴보았다. 동방문화권에 있던 한반도는 대륙에 연결된 것만큼이나 대륙문화와 뿌리를 같이하여 왔고, 생활문화와 정신사고의 구조까지 많은 유사성을 지니고 있음을 확인할 수 있다. 여기서 유사문화권에 있는 이 지역의 동굴문화를 조사, 고찰하였다. 석회동굴 분포가 주류를 이루는 중국 동북지역에서 요녕성 본계시에 속해있는 본계 수동굴, 본계 천룡동굴, 환인현의 망천동굴을 탐사하고, 환인현에 위치한 옛 고구려 궁성 터인 오녀산성을 탐방하여 그 시대의 찬란한 문화를 회상하고 오늘의 우리문화를 재조명하였다.

멸종위기종 붉은박쥐의 개체군 경향과 보호 관리 - 동면처의 장기 모니터링 결과를 중심으로 (The Population Trend and Management for Conservation in Myotis formosus)

  • 김선숙;최유성
    • 생태와환경
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    • 제50권4호
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    • pp.411-421
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    • 2017
  • 온대지역에서 동면박쥐에 대한 분포와 생태정보는 대상 종의 보전 및 서식지 보호 관리의 효율성을 높인다. 본 연구에서 멸종위기종인 붉은박쥐 개체군 경향 분석과 생태적 요구 조건을 파악하여 보호 관리 방안을 제시하고자 하였다. 2007년부터 2016년까지 조사를 수행한 결과, 전국 58개의 동면처에서 붉은박쥐 570개체가 확인되었다. 붉은박쥐가 이용한 동면처의 유형은 자연동굴에 비해 폐광산이 많았으며, 폐광산에서 보다 더 많은 붉은박쥐 개체가 동면하는 것이 확인되었다. 붉은박쥐의 동면처는 평균 $12.13{\sim}15.07^{\circ}C$의 온도와 92% 이상의 습도가 동면기간 동안 안정되게 유지되었다. 장기적인 모니터링 자료를 바탕으로 멸종위기종인 붉은박쥐의 개체군의 변화를 평가하기 위하여 TRIM을 이용하여 분석한 결과, 붉은박쥐 개체군의 변화는 안정적인 것으로 평가되었다. 그럼에도 불구하고 일부 동면처 사례를 통하여 동면처의 구조 및 환경 변화로 인한 붉은박쥐 개체수가 급감되는 사실을 확인하였다. 본 연구는 장기 모니터링 결과에 근거한 개체군 경향분석 결과와 현장 사례를 분석을 통하여 멸종위기종인 붉은박쥐의 보전 및 서식지 보호 관리 방향을 제시한다. 따라서 멸종위기종인 붉은박쥐의 서식지 보호 관리 방안은 방향은 종의 온도 선호도 및 서식지 환경이 변화되지 않도록 유지하는 것과 서식지 내 인위적인 간섭요인을 차단하는 것은 중요 사항이 될 것이다.