• 한국토양비료학회지
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• 제27권4호
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• pp.315-320
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• 1994

This survey report introduced briefly peat deposits in SAKHALIN island of eastern SIBERIA continent. Peat industry was promoted as leading resources for development in this island by national control economic plan of central government before CIS. But development of deposit was left suspension of operation due to investment now. In southern area, about 10km from Yuzunosakhalinsk, two deposits of peat field were explored. One of them (Troisk) was suspended at begining stage of peat harvest from 300ha field and the other(Missilop) was producing the compact peat through drying and pulverizing from 350ha peat field which showed long run harvest activities. There are plenty of peat deposits near the Polonai Reika (river) in the central area of this island, At Zbaikaritz, 40km nothern area from Polonaisk, 135ha of peat field was developed. This field was left without working but established field preparation and could be able to be harvested any time if machines and utlities were settled. At southern suburb 10km from Polonaisk, about 40ha field of virgin deposit has been established planning for development. The plan involved estimated amount of peat, deposit depth, water level, drainage and leading road. The most of peat deposits accumulated from sphagnum moss. Texture is coarse but it contains more than 95% of organic carbon near to 0.5% of total nitrogen and acidity showed pH4-5.

• 한국지형학회지
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• 제26권4호
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• pp.141-145
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• 2019

This study investigated Quaternary sand deposits in the process of surveying Quaternary deposits distributed in Yonghan-ri, Heunghae-eup, Pohang city. Field geological surveys were conducted and OSL dating samples were taken. The altitude of the Quaternary sand deposits layer is about 15m, and there are two upper and lower sand dune layers, and a peat layer is developed between them. The sampling point are just above the peat layer, and the altitude level is about 13.4m (YHO-1) and about 13.7m (YHO-2). OSL dating was performed for YHO-1 and YHO-2 and the results were 69 ± 6 ka and 62 ± 5 ka, respectively. The date analyzed are interpreted as MIS 4. On the other hand, the formation time of the peat layer at an altitude of about 13.2 to 13.7m can be compared with the results of the OSL dating of the above sandy deposits. The peat layer can be inferred to have formed during MIS 5a or earlier.

• Geomechanics and Engineering
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• 제9권4호
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• pp.415-426
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• 2015

Researches have been done to discover ways to strengthen peat soil deposits. In this model study, fibrous peat that is the most compressible types of peat has been reinforced with precast peat columns stabilized with ordinary Portland cement and polypropylene fibres. Rowe cell consolidation tests as well as plate load tests (PLTs) were conducted on various types of test samples to evaluate the strength and deformation of untreated peat and peat reinforced by various types of columns. PLTs were conducted in a specially designed and fabricated circular steel test tank. The compression index ($C_c$) and recompression index ($C_r$) of fibrous peat samples reduced considerably upon use of precast columns. Also, PLT results confirmed the results obtained from Rowe cell tests. Use of polypropylene fibres added to cement further decreased ($C_c$) and ($C_r$) and increased load bearing capacity of untreated peat. Finite element method (FEM) using Plaxis 3D was carried out to evaluate the stress distributions along various types of tested samples and also, to compare the deformations obtained from FEM analysis with the actual maximum deformations found from PLTs. FEM results indicate that most of the induced stresses are taken on the upper portion of tested samples and reach their maximum values below the loading plate. Also, a close agreement was found between actual deformation values obtained from PLTs and values resulted from FEM analysis for various types of tested samples.

• Journal of Plant Biology
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• 제14권3호
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• pp.66-73
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• 1971

Pollen analysis was made on peat deposits in the area of Pyung Taek County, Central Korea. Arboreal pollen(AP) of Alnus, Abies, Ligustrum, Viburnum and Carpinus composed 70-80% of the total pollen detected in this sample area. Judging from the large amount of arboreal pollens, one can assume that those species were dominant in this district when the pollen was deposited. Among the arboreal pollens, Alnus pollen occurred more often than any other trees. Pollens of Betula, Tilia and Ulmus occurred rarely in each layers of peat deposit. The pollen diagram showed that Pinus and Abies markedly increased from the bottom to the top of the peat, while Ligustrum, Quercus and Tilia decreased proportionately. Non-arboreal pollens (NAP) and spores composed about 30 percent at the lower layer, but decreased considerably in the upper layer.

• 대한지리학회지
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• 제33권2호
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• pp.127-142
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• 1998

Unsan alluvial plain is the backmarsh of Seomseokcheon which is a river originated from Chilseongdae(954m) on Mts Taeback, flowing into Donghae in southern Kangreung City, Kangwon Province. The vegetation change, geomorphic develoopment and depositional environment during the late Holocene have been investigated, using the methods such as boring, pollen analysis and radiocarbon dating. Because the deposits fo the study area are mainly consisted of peat and paety sand, they contained many pollen fossils. The peat layer has been sedimented since the high sea-level periods, 3,200 y. BP, and the records of vegetation change until now has well preserved here. According to archeological researches and the results of pollen analysis in east coast of Korea, it is supposed that the prehistoric rice farming in this area has begun since ca. 1,800 y. BP.

• 한국지형학회지
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• 제24권3호
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• pp.1-11
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• 2017

The pollen analysis on the deposits of the lower marine terrace I of the estimated paleoshoreline height of 18m was performed in order to estimate the formation age of this terrace developed at the Sanha-dong coast, Ulsan, southeastern coast of the Korean peninsula. The pollen assemblage of the peat layer of SH-1 pollen zone (Quercus-Ulmus/Zelkova zone), lying directly on the marine rounded pebble layer of this terrace, shows that the climatic environment of the deposition period of SH-1 pollen zone was almost similar to that of the Postglacial climatic optimum period, but slightly cooler than that of the late warm stage of Last Interglacial(MIS 5a) in the eastern coast of Korea. This heightens the possibility that the deposition period of the marine rounded pebble layer which was covered by the above SH-1 peat layer is the MIS 5e which has been estimated by a previous study of the sedimentary facies of this terrace deposits (Choi, 2016). The pollen assemblage of SH-2 pollen zone (Pinus-Quercus zone) shows that the climate of this period was almost similar to that of the late Postglacial, but slightly cooler than that of the period of SH-1 pollen zone. This means that the climate around the Sanha-dong was still warmer in the deposition period of the peat layer of SH-2 pollen zone. Thus, the peat layer of SH-2 pollen zone was considered to have been deposited during the period from the early regression stage of the MIS 5d which is the estimated final stage in the deposition period of the above peat layer of SH-1 pollen zone to any stage in which the warmer environment of MIS 5 has still lasted. The humic silt layer of SH-3 pollen zone (Pinus-Ulmus/Zelkova-Abies zone) is assumed to have been deposited during the interstadial of the Last Glacial (MIS 3).

• 한국지형학회지
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• 제17권2호
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• pp.63-76
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• 2010

전라남도 신안군의 대장도에 있는 장도습지는 유역면적이 약 147,000m²인 산지의 완경사면에 위치하고 있다. 이 습지는 그 동안 퇴적층에 대한 적절한 자료 없이 이탄층에 의해 형성된 습지로 알려져 있었다. 이 연구는 장도습지 및 그 주변의 지형을 분석하고 퇴적물 특성을 밝히는 것을 목적으로 하였다. 이를 위해 GIS를 이용하여 습지의 유역환경을 분석하였고, 현장조사를 통해 습지퇴적층의 분포와 깊이를 측정하였다. 또한 습지 퇴적물에 대하여 입도분석, 유기물분석, 원소분석, 방사성탄소연대측정을 실시하였다. 연구결과, 장도습지 퇴적층의 평균 두께는 약 30 cm로 측정되었으며, 구성물질의 평균 입도는 50~500μm였고, C/N비는 평균 11.5였다. 습지퇴적층의 유기물함량은 5~26%로 이탄의 기준에 미치지 못했다. 습지퇴적층의 유기물에 대한 방사성탄소연대는 180±50 ¹⁴C yr BP와 1950년대 이후로 측정되어 습지형성 이후 농경을 비롯한 자연적·인위적 교란이 지속적으로 발생하였음을 가리켰다. 결론적으로, 장도습지는 아직까지 초기단계의 습지로서 정상상태에 이르지 못하였기 때문에 작은 교란에도 민감한 변화를 나타낼 것으로 추정되었다.

• 한국환경생태학회지
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• 제29권1호
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• pp.69-80
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• 2015

Studies on Trapa of Korean, Japanese, and Chinese origins have been generally limited to currently living Trapa, thereby demonstrating the lack of phylogenetic approaches. In the present study, we conducted a numerical taxonomic study on 34 Korean origin Trapa species newly discovered in peat deposits. By using the numerical taxonomy as well as geological data, we created an appearance map based on the periods and taxonomic groups of the Korean Trapa. Further, by using this appearance map, we reviewed the limitations that exist in the taxa and simultaneously discussed the adaptational environment of Trapa in each period. Although other studies have discussed new variants of Trapa worldwide, including T. litwinowii V. vassil. var. chihuensis S.F.Guan & Q.Lang of China (Guan and Lang, 1987), the present study is significant because it provides data on the origin of Korean Trapa species. The availability of such data is essential in determining the adaptational environment of the presently living Trapa. To our knowledge, this is the first report of approximately 10 newly discovered and other presently living species of Trapa. Further, the appearance map in the present study allows the use of the 10 newly discovered species and variants of 34 Trapa species indigenous to South Korea for over 1000 years, for a comparison with the currently living Trapa species. Thus, the present study results could serve as important basic data to understand the adaptational environment of the genus Trapa. from the past to the present in Korea.

• 한국지형학회지
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• 제23권2호
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• pp.47-59
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• 2016

The formation age and depositional environment of the marine terrace I of the estimated paleoshoreline altitude of 18m in Sanhari of Ulsan coast, southeastern Korea were investigated on the basis of examination of lithofacies and stratigraphy of terrace deposits. Marine deposits of the terrace is composed of rounded boulders(70cm in diameter) and rounded pebbles(1.0cm in diameter) which overlay them. The above rounded boulders which lie on the paleo-shore platform are considered to have been formed by wave abrasion in the same period that the paleo-shore platform was developed. The rounded pebbles which lie on the rounded boulder layer are considered to have been deposited in gravel beach and berm environment, judging from the laminae developed in this layer. The paleo-shore platform and marine rounded gravel layer of the terrace are assumed to have been formed in the large transgression period of the Last Interglacial culmination stage(MIS 5e), judging from the comparision of the formation age of 125ka B.P. of Juckcheon terrace I in the adjacent Pohang coast which was dated by amino acid dating. The terrestrial deposit of this terrace was largely composed of angular and subangular gravel mixed with marine rounded pebble which has been carried away mainly from the deposit of previous marine terraces and redeposited in this terrace. The lowest peat layer of terrastrial deposit was considered to have been deposited during the period from the late MIS 5e which is the estimated finishing time of deposition of the above marine gravels to the early stage of following regression period(MIS 5d) in which the sea level was still high. The sediments of angular and subangular gravel deposit which lie on this peat layer were assumed to have been deposited during the period from the early stage of the first regression period(MIS 5d) of the Last Interglacial to the Last Glacial. The lower part of the angular gravel layer is composed of the deposits of the fluvial and colluvial sediments, whereas most of the upper and middle part of the layer is mainly composed of angular gravels of colluvial sediments formed in the cold environment.

• 한국토양비료학회지
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• 제18권3호
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• pp.265-275
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• 1985

본(本) 조사연구(調査硏究)는 호남지방(湖南地方)의 하해혼성평탄지(河海混成平坦地)에 산재(散在)하는 유기질토시(有機質土尸) 함유(含有) 답토양(畓土壤)의 형태적(形態的) 특성(特性), 분포(分布), 생성원인(生成原因), 그리고 지형(地形)과 이들 유기질토시(有機質土尸)과의 관계등(關係等)을 구명(究明)하여, 토양(土壤)의 효율적(效率的)인 이용(利用) 및 관리(管理)와 개량연구(改良硏究)에 기초자료(基礎資料)를 제공(提供)코져 조사연구(調査硏究)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. 호남지방(湖南地方)에 분포(分布)된 유기질토시(有機質土尸) 함유(含有) 답토양(畓土壤)은 총(總) 6,538ha로서, 전국(全國) 유사토양(類似土壤)의 64.7%에 해당(該當)하였으며, 이탄(泥炭)의 매장양(埋藏量)은 약(約) 241만(萬)M/T로 추정(推定)된다. 2. 유기질토시(有機質土尸) 함유토양(含有土壤)은 대부분(大部分)이 만경(萬頃) 동진강유역(東津江流域)(호남평야(湖南平野))에 분포(分布)하며 (97.6%), 일부(一部)는 영산강유역(榮山江流域)인 나주평야(羅州平野)(1.5%), 및 완도(莞島), 여천지역(麗川地域) (0.9%)에도 일부(一部) 분포(分布)되어 있었다. 3. 이탄(泥炭)의 생성(生成)은 B.C 4250연경(年頃)의 승문시대전기(繩文時代前期)로 추정(推定)되며, 공덕통(孔德統)과 봉남통(鳳南統)은 소하천(小河川)이 있는 곡간지(谷間地) 및 구릉지(丘陵地)와 인접(隣接)한 소택지(沼澤地)에서 생성(生成)되었고, 금제통(金堤統)은 구릉지(丘陵地)와 인접(隣接)한 저습지(低濕地)에서 발달(發達)되었다. 4. 이탄(泥炭)의 생성원인(生成原因)은 갈대, 풀등(等)의 자생섬유질(自生纖維質) 이탄(泥炭)이 집적(集積)된 것은 금제통(金堤統)이며, 이와 병행(竝行)하여 자생이탄(自生泥炭)과 일차타생이탄(一次他生泥炭)의 목질(木質) 및 섬유질이탄(纖維質泥炭)이 동시(同時)에 집적(集積)된 것은 공덕(孔德), 봉남통등(鳳南統等)인 것으로 추정(推定)되었다. 5. 공덕통(孔德統) 단면중(斷面中)의 흑이시(黑泥尸)와 이탄시(泥炭尸)은 각각(各各) 62-68cm 및 68-137cm에서 나타났고, 봉남통(鳳南統)은 52-84cm 및 84-113cm에서, 그리고 금제통(金堤統)의 흑이시(黑泥尸)은 46-71cm 부위(部位)에서 나타났다. 6. 각(各) 토양(土壤)의 토시부호(土尸符號)는 흑이(黑泥) 및 이탄시하부(泥炭尸下部)의 토시(土尸)을 Cg시(尸)으로 하였으며, 유기물시(有機物尸)의 흑이시(黑泥尸)은 Aag로, 이탄시(泥炭尸)은 0로 하여 유기물형태(有機物形態)에 따라 Oag 및 Oig로 구분(區分)하였다. 7. 곡간폭(谷間幅)과 흑이(黑泥) 및 이탄시(泥炭尸)의 출현(出現) 깊이는 공덕통(孔德統)에서 정(正)의 상관(相關)이 있었으나($r=0.881^{**}$, $r=0.827^{**}$ 봉남통(鳳南統) 및 금제통(金堤統)은 일정(一定)한 경향(傾向)이 없었다.