• Title/Summary/Keyword: terraces

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Relationship between early development of plant community and environmental condition in abandoned paddy terraces at mountainous valleys in Korea

  • Park, Jihyun;Hong, Mun-Gi;Kim, Jae Geun
    • Journal of Ecology and Environment
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    • v.36 no.2
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    • pp.131-140
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    • 2013
  • In Korea, many paddy fields in mountainous area have been abandoned because of their low accessibility and rice price and the abandoned paddy terraces have changed into natural lentic wetlands. To understand the relationship between characteristics of environmental conditions and early development of plant community in abandoned paddy terraces, we investigated at four well-maintained abandoned paddy terraces in 3 different climatic zones in Korea. Soil texture of abandoned paddy terraces was mostly kinds of loam and electric conductivity of soil was also similar among abandoned paddy terraces. On the other hand, contents of nitrogen, phosphorus, potassium, sodium, magnesium, and calcium in soil were relatively low and significantly different among abandoned paddy terraces. Water depth was different within sites and inter-sites. Although environmental conditions including climate, soil condition and water depth were different among abandoned paddy terraces, the compositions of plant communities were relatively similar in all abandoned paddy terraces. 55 dominant taxa out of 141 recorded species were commonly recorded over sites and they were mostly perennial obligate wetland plants and facultative wetland plants. 8 taxa out of 55 dominant taxa occurred at all abandoned paddy terraces with over 10% coverage. Several site-specific species occurred at site, which have some area with deep water level. This result indicates that early development of plant community in abandoned paddy terraces of similar water regime is similar in the entire area of Korea even though environmental conditions such as climate, biogeographic history and soil are different.

River Terraces and Geomorphic Development of Subi Basin, Yeongyang (하안단구와 수비분지의 지형발달)

  • Son, Myoung Won
    • Journal of The Geomorphological Association of Korea
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    • v.24 no.2
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    • pp.15-25
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    • 2017
  • Subi basin is located at the crestline of Taebaek mountains. This paper aims to elucidate the geomorphic development of Subi basin through the analysis of river terraces built in Wangpi-cheon and Banbyeon-cheon. Wangpi-cheon flows northeastward from Subi basin, and Banbyeon-cheon flows southward at the west of Subi basin. Absolute age of terrace is measured by means of OSL methodology, long profile of Wangpi-cheon is made up with 10m interval contour line, and the elevation above river bed of high terraces is measured at the end part of terrace. The results are as follow: Firstly, high river terraces of Subi basin, Wangpi-cheon and Banbyeon-cheon are formed about 40 kyr(MIS 3) being interstadial stage of last glacial period. Secondly, the elevation above river bed of high terraces of Wangpi-cheon and Banbyeon-cheon tends to increase toward upstream. It means that the uplift of Taebaek Mountains influences considerably the formation of their terraces. Thirdly, the elevation above river bed of high terraces at the reach from Seomchon to Suha-ri of Wangpi-cheon tends to decrease toward upstream. This section is captured from Banbyeon-cheon flowing in the opposite direction. River piracy has occurred from the time of formation of Suha-ri high terrace to the time of formation of Hantee wind gap. Finally, for fluvial system of Wangpi-cheon to establish dynamic equilibrium, topographic axis will move toward Banbyeon-cheon.

A Study on Natural Scene Figuration Possibility - Centering around Gyeongnam Area(Namhae Gacheon Village, Sancheong Imchon Village, Hamyang Doma Village) Rice Terraces - (자연경관 조형화 가능성에 관한 연구 - 경남지역(남해가천마을, 산청임촌마을, 함양도마마을) 다랑이논을 중심으로 -)

  • Youn, Kyung-Sook;Lee, Jae-Keun
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.28 no.1
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    • pp.113-119
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    • 2010
  • This study examined figurative characters of rice terraces, and is intended to seek figurative possibility of a natural scene by selecting Gyeongnam Area Namhae Gacheon rice terraces, Sancheong Imcheon rice terraces and Hamyang Macheon rice terraces through an analysis of the target land. As a theoretical background, studies of a natural scene and figuration-related literature were looked into, and for figuring a natural scene on the basis of the results, the character of the topography of rice terraces was divided into 9 items as follows by generalizing the inspiration obtained from the natural scenic character and spatial character of rice terraces represented from the topography: (1) Inclination showing the degree of the slope of rice terraces, (2) The bending showed by unevenness of the edge line of rice terraces, (3) The degree of parallelism of the up-and-down edge line, (4) The size of the width of the section of each rice terrace, (5) The area of the total rice terraces, (6) Step gap that indicates the difference of high and low of the up-and-down small rice terraces, (7) Figuration as an image represented by the external form of the total rice terraces, (8) Naturalness and artificiality kept by the total scene, (9) Softness of cornerstones or soil that forms small rice terraces, an atmosphere produced by the total scenes, etc. The results of analysis made through GIS, with rice terraces of Gyeongnam Namhae, Sancheong and Hamyang Area as the target land, are as follows. First, the steeper the inclination is, the higher the step difference of cornerstones becomes, and the steeper the inclination, the narrower the area and width become, so that it could be known that, in rice terraces, inclination is proportional to step difference and the area is inversely proportional to the width. Second, it is considered that line showed in rice terraces, area elements and reiteration, repeated changes, and changes in the scene affected by the surrounding environment including those according to season can be converted into a variety of images according to an individual disposition. Third, it was decided that it is possible to figure repetitive composition and directivity, motility, order and change, etc. into a common type drawn from each target land. This paper, as a study of basic materials for expressing figuration in an environment field, investigated and analyzed the surrounding environment of the target land, and is significant in that it attempted the possibility of being able to generalize the environmental beauty of the target land as one figurative element. More precise studies are expected to be made later.

Marine Terraces of the Eastern Coast of Korean Peninsula

  • Park, Seong-Gil
    • The Korean Journal of Quaternary Research
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    • v.17 no.2
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    • pp.15-15
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    • 2003
  • In South Korea, marine terraces have been well developed along the eastern coastal zone, and previous researches on the marine terraces have also been focused on to this coastal zone. The marine terraces of the eastern coast of South Korea had been classified into three terrace groups, that is, the higher, middle, and lower surface ones, according to the heights of marine terraces by previous studies(Oh, 1981 ;Chang, 1987 ;Yoon et. al, 1999, 2003 ; Hwang and Yoon, 1996 etc.). Recently, however, it tends to classify the marine terraces based on the concept of geomorphic surface units(Lee, 1987 ; Kim, 1990 ; Choi, S. 2003; Choi S. et. al 2003a,b, etc). For example, it was proposed that the marine terrace surfaces of Eupcheon coast of the southeastern coastal area of Korea could be classified into 16 geomorphic surfaces, i.e., Eupcheon 1terrace(former shoreline height of 160m), 2(153m), 3(140m), 4(130m), 5(124m), 6(115m), 7(100m), 8(92m), 9(82m), 10(71m), 11(62m), 12(53m), 13(43m), 14(35m), 15(18m) and 16(10m) surfaces, in descending order, according to the former shoreline heights(Choi, S, 2003 ; Choi, S. et. al, 2003a,b). Among these terraces, Eupcheon 1, 2, 4, 5 and 7 surfaces had not been reported in previous works. Among the above mentioned marine terraces, Eupcheon 15 terrace, the most widely and continuously distributed marine terrace have been identified as marine terrace of the Last Interglacial culmination period(oxygen isotope stage 5e) which was based on amino acid dates(124∼125ka BP) and geomorphological features such as red soil, pollen analysis, fossil cryogenic structures and crossing terrace concept. Eupoheon 15 terrace surfaces have also been proposed as the key surface for the identification and correlation of the so-called '5e' marine terrace in the eastern coast of South Korea. This terrace was reconfirmed as the Last Interglacial culmination period, which was based on the identification of Ata tephra, one of the wide-spread marker tephra which indicates the Last Interglacial culmination period in Japan by Sasaki et. al(2002). It was thought that marine terraces of the eastern coast of South Korea had been formed by the steady-state uplifting during the Quaternary glacio-eustatic sea level changes(Choi, 1997). The uprift rate of 10cm/1,000years had been proposed in the eastern coast of South Korea based on the former shoreline altitude(18m) of the above Eupcheon 15 terrace. Therefore, it can be estimated that Eupcheon 1 terrace had been formed in the early Pleistocene from the above uprift rate. The OSL dating for the samples of Eupcheon 7, 9, 13, 15 and 16 terraces and identification of marker tephra in the terrace deposits are in progress. It is expected that more elaborate chronology on themarine terraces of the eastern coast of South Korea could be established by these absolute dates and marker-tephra.

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Mechanism of the Marine Terraces Formation on the Southeastern Coast in Korea (한국 남동해안 해안단구의 지형형성 mechanism)

  • 윤순옥;황상일
    • Journal of the Korean Geographical Society
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    • v.35 no.1
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    • pp.17-38
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    • 2000
  • The marine terraces often offer come important clues to understand the topographic development during the Quaternary and the present landforms in korea. We examined the mechanism of the marine terraces formation along the coast from Samjung-Ri(community), Guryongpo-Eup(county) to Haseo-Ri, Yangnam-Myun(county), Gyungju-Si(city). Among the various but unique factors of the given coastal environment, which should contribute to the marine terraces formation together, we focused on five possible factors for the present stydy. Geologic difference in bedrocks, protrusion degree of coastiline, topological relief of sea-bottom, fluvial characteristics on land, and pattern of the waves appeared to act cooperatibely on the terrace formation of Southeastem coast in korea, while the fluvial characteristics seemed play a significant but localized role in it. Wide distribution of middle surfaces on the coast of Samjungri-Janggilri could be due to the concentration of the high waves and the weakness of the Tertiary volcanic rocks. For the sporadic distribution of the terraces on the coast of Gupungri-Gyewonri, it seemed attributable to the erosion -susceptible weak bedrock, the coastline of inner bay, shallow sea-bottom with the gentle relief, and other fluvial characteristics with the low divides. Together with the geologic difference in bedrock, other factors including protrusion degree of coast, topological relief of sea-bottom, and the transportation loads by the stream Daejongchon are believed to act cooperatively on the mechanism of the marine terraces formation on the coast of Duwonri-Upchonri.

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The Geomorphic Development of River Terraces along the Middle and the Lower Parts of the Osip-cheon River in Samchok City (三陟 五十川 중.하류부의 河岸段丘 지형발달)

  • 윤순옥;황상일;정석교
    • Journal of the Korean Geographical Society
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    • v.37 no.3
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    • pp.222-236
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    • 2002
  • The Osip-cheon river flowing on the east side of the Taeback mts. has formed river terraces on the several heights along the middle- and downstream. The river terraces are classified into 5 climatic ones and 7 thalassostatic ones. The thalassostatic ones are found to the height of 145-l50m level at 20-30m intervals. These vertical distribution is caused by the continuous uplift and periodical rise and fall of the sea-level. The high higher surfaces among the thalassostatic ones are the highest among those of Korea. The chronologies of the terraces are correlated to the marine oxygen isotope stages : The thalassostatic terraces on the level of 40 m.a.s.l. are to the stage 7, 70 m.a.s.l.. to the stage 9, 90 m.a.s.l. to the stage 9, 110 m.a.s.1. to the stage 11 and those of 150 m.a.s.1. to the stage 15 among the Interglacial Ages. The landuses and geomorphic landscapes of the Samchok area are chracteristic, because the karst landforms, such as doline and uvala, are developed on the surfaces of the middle-, the higher- and the high higher surfaces of river terrace.

Concepts and Geomorphic Properties on Fluvial Terraces (하안단구의 개념과 지형 특성)

  • Lee, Gwang-Ryul
    • The Korean Journal of Quaternary Research
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    • v.25 no.1
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    • pp.1-13
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    • 2011
  • To reinterpret the meaning of fluvial terraces in the Quaternary researches, the concepts and geomorphic properties of fluvial terraces are reviewed. Fluvial terraces are the alluvial landform that was once river channel or floodplain by paleochannel flowed in elevated areas from the current river by active incision of rivers due to the climatic changes and/or uplifts. As fluvial terraces are the remnants of alluviums after incisions of rivers, the major factors influencing on the incisions are the falling of erosion base, increase of river discharge and distinct geomorphic phenomenon of river. While it is generally known that fluvial terraces deposits in the upper or middle reaches of large rivers were formed during glacial periods, the deposits may be formed at the various periods due to the diverse natural environments and geomorphic properties of specific rivers, because there have been numerous cases that the ages of fluvial terraces in the upper or middle reaches of large rivers in Korea and China can be correlated to the interglacial periods.

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Fluvial Terraces of the Lower Yeongsan River, Southwestern Coastal Region of Korean Peninsula (영산강 하류 지역의 하안단구)

  • Choi, Seong-Gil
    • The Korean Journal of Quaternary Research
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    • v.18 no.1 s.22
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    • pp.41-46
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    • 2004
  • The fluvia(thalassostatic) terraces have been developed among the lower Yeongsan river, near the southwestern coastal region of Korean peninsula. These thalassostatic terraces could be classified into 3 surface, i. e., Yeongsan 32m, 18m, and 10m surface, in desending order, according to the relative heights from the river floor. Yeongsan 32m, 18m and 10m surfaces were corresponded to the mMT3, mLT1 and mLT2 surfaces of Choi(2003), respectively. It was revealed that the mLT1 surface was the marine terraces which had been formed in the Last Interglacial culmination period(oxygen isotope stage 5e) in the southeastern coast of Korean peninsula.

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Geochemical weathering properties of marine terrace sediment at Gangneung-Donghae area, South Korea (강릉-동해에 분포하는 해안단구 퇴적물의 지화학적 풍화 특성)

  • Hong, Seongchan;Choi, Jeong-Heon;Kim, Jong Yeon
    • Journal of The Geomorphological Association of Korea
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    • v.23 no.2
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    • pp.95-108
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    • 2016
  • Several flights of marine terraces were developed along the Eastern coast of Korea (Gangneung-Donghae). Various dating techniques have been applied to determine the age of these terraces, with a view to better understand the regional uplift history. In this study, we compare the major element compositions of the terrace deposits and modern beach sediments to estimate the relative formation age of these terraces. We observed a discernible difference in major element geochemistry between modern beach sediments and various elevated terrace deposit (i.e. palaeobeach sediments). In general, weathering properties of marine terrace sediments are expected to be affected by the formation ages of terraces, and here, we confirm that the chemical composition are indicative of the relative age of the terraces in this region.