• 한국지반환경공학회 논문집
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• 제14권12호
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• pp.43-52
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• 2013

석회암은 일반적으로 망상형 공동이나 석회암 동굴 같은 대규모 공동을 형성시키고, 싱크홀과 돌리네 형태로 발전하기도 한다. 이러한 공동은 도로, 댐 등을 건설할 때 지반이 상부구조물을 지탱하지 못하여 부등침하 등으로 심각한 문제를 야기할 수 있어 공동충전 등의 보강이 필요하게 된다. 본 연구에서는 CGS 공법에 의한 석회암 공동지역의 구조물 기초 지반보강을 실시하고, 이를 통해 보강효과를 공학적으로 평가하였다. 먼저, 시추조사를 통해 지반의 구성 및 공학적 특성을 파악하였다. 또한, CGS 보강을 실시한 후, 보강검증을 위해 시추조사를 실시하였고, 시추조사 시 채취된 보강재코어 중 대표적인 시료에 대해 암석시험을 실시하여 보강재에 대한 물리적 특성을 파악하였다. 그 결과 CGS 공법을 적용한 후, 시추조사 시 채취된 보강재코어 중 대표적인 시료에 대해서 압축강도시험을 실시한 결과 공동 내 재료의 충전 상태가 양호한 것으로 나타났으며, 일축압축강도도 12.2~19.2(MPa)로 충분한 것으로 검토되어 석회암 공동이 적절하게 보강된 것으로 확인하였다.

• 대한환경공학회지
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• 제31권5호
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• pp.371-377
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• 2009

순산소연소 배가스 중 $CO_2$ 농도는 가스의 재순환으로 인해 95%까지 농축 가능하며, $CO_2$ 농도가 높은 조건에서 석회석의 소성특성은 기존의 공기 연소와 다르게 나타난다. 본 연구에서는 흡수제로 특성이 다른 세 종류의 국내산 석회석을 이용하여, 소성온도에 따른 석회석의 소성특성에 대해 알아보았다. 또한 흡수제 종류, 반응온도 등의 운전변수가 $SO_2$ 제거효율에 미치는 영향에 대하여 알아보고, 반응생성물을 포집하여 황 함량을 측정하였다. 소성온도가 증가함에 따라 석회석의 소성율 및 비표면적은 증가하는 경향을 보였으며, 반응온도가 증가함에 따라 $SO_2$ 제거효율은 증가하였으며 석회석의 종류에 따라 $SO_2$ 제거효율이 뚜렷한 차이를 보였다. 최고효율 나타낸 석회석 시료에 대한 반응생성물 분석결과 시료 내 황 함량은 약 10% 정도인 것으로 나타났다.

• 한국농공학회논문집
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• 제54권3호
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• pp.1-9
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• 2012

As topographic characteristics of Korea where 64 % of the national land area is forest and only 17 % is being used as farmland, remediation of farmland contaminated by heavy metals is a considerably important issue. In this study, as an alternative of practically and effectively remediating farmland which was abandoned as its crop plants exceeded maximum residue limit of heavy metals due to mining impact, applicability of stabilization method was examined through the pilot-scale field experiment. Three plots ($L{\times}W{\times}D=3m{\times}2m{\times}0.3m$) were installed at the selected farmland and in plot 1, only soil of the selected farmland was applied, in pilot 2, soil of the selected farmland plus 3 % limestone (w/w) was applied and in pilot 3, soil of the selected farmland plus 3 % limestone was applied and then uncontaminated soil was covered thereon (0.3 m). After that, seeds of radish, Korean cabbage and soybean of which characteristics of edible portions are different were sowed on each plot and cultivated. Afterwards, at a proper harvesting time (app. 80 days later), crop plants and soil were collected and phytoavailability (0.11 M HOAc extractable) of heavy metals in soil and accumulated concentration of heavy metal in edible portion of crop plants were examined. As a result, it was revealed that phytoavailability of heavy metals in soil added with limestone (plot 2) was clearly reduced compared with plot 1 (untreated) and owing to this treatment, accumulated concentration of heavy metals in edible portion of crops was also clearly reduced compared with plot 1. While radish cultivated in plot 1 had exceeded maximum residue limit of agricultural products, in particular, plot 2 using limestone had shown concentration lower than maximum residue limit and this plot had shown little difference with 3 plot where crop was cultivated in uncontaminated soil cover. Therefore, it was considered that for abandoned farmland like the selected farmland, reducing mobility and phytoavailability of heavy metals and reducing crop uptake through stabilization method would be an effective and practical alternative for producing safe agricultural products on a sustained basis.

• 환경생물
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• 제25권3호
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• pp.228-238
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• 2007

Calcium plays an important role for the organisms' physiology, reproduction, and growth. Calcium amount and transfer efficiency along trophic levels were compared at two different geological areas, Limestone area (LS) and Granitic Gneiss area (GG) in 1992 and 1993. Biomass and calcium amount of plants, herbivores and carnivores were seasonally measured. The removal sweeping net method was used to collect the quantitative insect samples. Calcium content (mgCa $g^{-1}$ DM) and pH of soil were 4.85 and 7.3 at LS and 0.21 and 7.3 at GG. The calcium transfer efficiencies (%) at LS and CG were 0.2 and 4.2 from soil to plants, 0.002 and 0.02 from plants to herbivores, and 73 and 47 from herbivores to carnivores, respectively. As a whole, the high calcium content of the LS soil reduced the utilization of calcium by plants. The higher trophical levels were, the higher ecological efficiency of the biological levels was. The calcium transfer amount was higher at LS, but its efficiency was rather higher at GG.

• 식물분류학회지
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• 제48권3호
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• pp.218-229
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• 2018

Myanmar's plant diversity is expected to be very high given the wide variety of climates and the diverse vegetation and geographical features of the country. Since the publication of Kress et al.'s plant checklist in 2003, new and unrecorded species have been constantly reported by various botanists, but much of Myanmar's flora requires more intensive examinations. We conducted joint floristic surveys of several Ywangan areas, including the Panlaung-Pyadalin Cave Wildlife Sanctuary in southern Shan State of Myanmar. The initial identification of seed plant specimens collected from three short floristic expeditions revealed that 23 species were newly recorded species in Myanmar. More than half of these were found to be geographically notable species, which are known to be endemic to neighboring countries such as China (4 spp.), Thailand (6 spp.), and India (2 spp.). A considerable number of these unrecorded species are distributed in the limestone areas of neighboring countries, reflecting the geological characteristics of the survey area. The results of this study reemphasize the need for intensive and continuous research on the flora of Myanmar for a more comprehensive understanding of the distribution patterns of flowering plants in Southeast Asia.

• 대한자원환경지질학회:학술대회논문집
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• 대한자원환경지질학회 2002년도 춘계 공동학술발표회
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• pp.280-282
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• 2002

We evaluated the potential of the limestone deposits distributed in the Uljin area, the north-eastern part of Gyungsang province, based on the results of the surface and underground geological survey. The geology of the Uljin area consists mainly of the Cambro-Ordovician Joseon Supergroup correlated to the Duwibong sequence of the south-eastern part of Gangwon province. The Joseon Supergroup rested unconformably on the Precambrian schists is divided into six formations , namely, Maesan, Gusanri, Namsusan, Songchon, Mongcheon, and Keummaeri formations in ascending order. Main geological structures are two thrust faults with NS trending, some normal and reverse faults, and folds.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 봄 학술발표회 논문집
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• pp.165-172
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• 2002

We presents an hazard zonation mapping technique in karst terrain and its assessment. From the detailed engineering geological mapping. Controlling factors of sink hole and limestone cave formation were discussed and 4 main hazard factors affecting hazard potential are identified as follows: prerequisite hazard factor(distributions of pre-existing sink holes and cavities), geomorphological hazard factors(slope gradient, vegetation, and drainage pattern etc.) geological hazard factors(lithology, fracture patterns and geological structures etc.) and hydraulic conditions(hydraulic head, annual fluctuation of ground water table and composition of g/w water). From the construction of hazard zonation map along the Jecheon-Maepo area, and vertical cross-sectional hazard zonations specific tunnel site we suggest hazard zonation rating systems.

• The Korean Journal of Ecology
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• 제14권2호
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• pp.159-169
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• 1991

Floristic cmposition and soil properties were analyzed in chines cork oak(quercus variabilis)cmmunities in the limestone area, tanyang, ch'ungbuk province in korea. The tree layer was composed of quercus dentata, platycarya strobilacea, fraxinus rhynchophylla and others as wel as quercus variabilis. the shrub layer was dominated by ulmus davidiana for. suberosa,shrubby q. variabilis. euonymus alatus and rhus chinensis. among these, u. davidiana for. suberosa was known to have a restricted distribution to calcareous area, and 9 species in the shrub layer including e. alatus, indigofera kirilowii and rhamnus davurica belonged to the calcicole. The herb layer was dominated by carex lanceolata and spodiopogen cotulifer. ten specirs including g. lanceolata, clematis mandshurica, isachne globosa, lithospermum arvense and scabiosa mansenensis belonged to the calcicode. soil texture was classified to clay loam in both top and subsoil. Water cotent and organic matter were consistentl higher in top soil than in subsoil. soil ph rangd 7.8~8.4. Total n concentration in top soil ranged from 0.2 to 0.4mg/g, which was higher than that in subsoil. Available p and exchangeable k concentretion were also significantly higher in op soil than in subsoil. However, exchangeable ca concentration was similar betweenthe top and the subsoil. Unlike the other nutrients, exchangeable mg concentration in top soil was lower than that in subsoil. orangic matter, n, p and k content in this chinese cork oak stand showed as much as the other noncalcareous sites. Soil properties in this study area seemed to have been influenced by casts forming activities of earthworms.

• 자원환경지질
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• 제7권3호
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• pp.101-122
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• 1974

The study area is located in between Susanri and Hwanggangri where the formations of Okcheon group and Chosun group supposedly come in contact so that the area is structurally very import. Present study reveals that the meta-volcanic rocks distribute from south to north along contact zone of Okcheon and Chosun groups in the center of the area. Meta-volcanic rocks seem to be originated from the andesite or andesitic basalt rocks which was known to be Surchangri formation consist of phyllite and black slate by previous workers. The meta-volcanic rocks intruded along the fault zone one existed between Okcheon and Chosun groups but obliterated at present by the intrusion of volcanic rocks. The fault seems to be overthrust, and one of the positive evidences of thrust fault is the Yamisan nappe structure in Yamisan near Susanri. This interpretation coincides with O.J. Kim's work which states that the Precambrian Okcheon group is largely overturned and thrusted over the Chosun group. The relation between the Surchangri and the Majeonri formation marks facies change. This fact together with northpluging anticlinal structure made it possible that both formation came into contact along direction without fault. Yongam formation is not overlain unconformably used to be believed by previous workers, but interbed in the Great Limestone series of Chosun goup. It is also clarified that the rock formerly designated as limesilicate rock was meta-liparite. The origin of amphibole pebbles in the Kunjasan formation is of primary and secondary ones; the secondary pebbles were formed by metamorphism of the fragments of limestone or dolomite.

• The Korean Journal of Ecology
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• 제25권3호
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• pp.145-152
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• 2002

1997년 임형탁에 의해 신종으로 기재된 자병취(Saussurea chabyoungsanica Im)에 대한 실체를 파악하기 위해 새로운 분포지를 조사하였고, 이 종에 대한 식생구조와 토양환경요인을 분석하였다. 자병취는 태백산맥계에 속하는 만덕봉, 석병산, 석개재, 덕항산의 능선부 등 모두 석회암 지대에서 발견되었고, 이들 지역 중 석개재는 하부대석회암층, 석병산, 만덕봉, 덕항산은 상부대석회암층에 속하는 지역이었다. 이들 지역에 자생하는 자병취의 식물사회학적 조사결과, 식물군락은 광의의 신갈나무군락군에 포함되는 자병취-산거울군락군, 조록싸리-자병취군락, 조록싸리-자병취전형하위군락, 대사초하위군락, 민둥갈퀴-자병취군락, 참배암차즈기-자병취군락, 털댕강나무-자병취군락 등 1군락군. 4군락, 2하위군락으로 분류되었다. 자병취의 생육지의 환경요인을 분석한 결과, 주로 북사면의 능선부에 분포하며, 토양의 pH는 $7{\sim}8$ 범위의 전형적인 석회암지대임을 보였고 토양의 수분함량이 높고 유기물함량이 낮은 것으로 나타났다. 조사지역의 토심이 $1{\sim}10cm$, 상대광도가 $30{\sim}45%$에서 높은 빈도로 출현하는 것으로 보아 암반나출지나 임연부의 관목층이 우점하는 곳에 주로 분포하는 특성을 보였다. 자병취 자생지의 식생구조를 파악하여 군락 구분을 한 뒤, 각 군락별 토양환경의 특성을 조사하였다. 군락별 토양시료의 PCA분석 결과, 토양환경요인의 특성에 의해 대체로 군락구분이 가능하였다. 이차원공간에 표현되는 기여율의 누적값은 73%로 토성과 유기물함량, 토양함수량 등이 주요 요인으로 나타났다.