• Title/Summary/Keyword: terraces

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Vegetation Structure and Distribution of Exotic Plants with Geomorphology and Disturbance in the Riparian Zone of Seunggi Stream, Incheon (인천 승기천의 하안지대에서 지형과 교란에 따른 외래식물의 분포와 식생 구조)

  • Sin, Dong-Ho;Jo, Gang-Hyeon
    • The Korean Journal of Ecology
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    • v.24 no.5
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    • pp.273-280
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    • 2001
  • We investigated the flora and vegetation structure of exotic plants along stream geomorphology and disturbance factors in the riparian zone of Seunggi stream, Incheon. Total 53 exotic plant species were found in the riparian corridors of Seunggi stream. The percentage of exotics ranged from 25% to 33% of total species richness, and its mean value was 24% in the whole riparian area. The percentage of exotics reflected the vulnerability of riparian zones to plant invasions by disturbances, and it could be used as an indicator of riparian system dysfunction. The distinct distribution patterns of exotic plants did not found in the lateral topographic features of the stream. Invasion and proliferation of the exotic plants were somewhat remarkable at terraces and bank slopes of the stream. Among various disturbance factors, plowing and trampling were important on the invasion of exotic plant species of Seunggi stream.

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Geomorphic Development of the Kajo Basin (加祚盆地의 地形發達)

  • Jo, Wha-Ryong;Chang, Ho;Lee, Jong-Nam
    • The Korean Journal of Quaternary Research
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    • v.1 no.1
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    • pp.35-45
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    • 1987
  • Several fluvial terraces were developed in the Kajo Basin located in Kochang-gun, Kyongsangnam-do, Korea. The peat layers are formed on a fluvial terrace of them. To clarify the geomorphic development of this basin, a detailed classification of geomorphic surfaces, a soil profile study, grain size analysis, pollen analysis of the peat layers and C-14 dating were made. The main findings are as follows: 1) The Kajo Basin was formed by a differential erosion of granic rocks. The surrounding mountains are contact-metamorphosed gneiss and sedimentary rocks. 2) Seven geomorphic surfaces were recognized. They are named the H1, H2, M1, M2, T, L1 and L2 surfaces, from older to younger. 3) C-14 dating and the pollen analysis indicate that the L1 surface was formed during the Early Wurm Glacial. 4) The formation periods of the L2, M and H surfaces are supposed to be the Late Wurm, Riss and Mindel glacial, respectively, on the basis of the color of soil horizons (with or without the Red Soil) and the weathering degree of gravels. 5) Betula and Pices were dominant in the pollen of the Kajo Basin around 30,000 years B.P.

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Long-Term Investigation of Regional Topographic Effects on Soil Chemical Properties and Heavy Metal Concentrations in Paddy Fields

  • Ahn, Byung-Koo;Kang, Seong-Soo;Shin, Jae-Yeon;Lee, Jin-Ho
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.5
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    • pp.738-743
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    • 2012
  • Topographic conditions of agricultural fields work as a important factor to identify different soil properties. This study was conducted to investigate the selected soil chemical properties and the concentrations of heavy metals, Cd, Cr, Pb, Cu, Ni, and Zn, in the paddy fields of different topographic areas at four year intervals from 1999 to 2011. Three-hundred soil sampling sites in the paddy fields were selected from the different topographic areas that were local valley and fans, fluvio-marine deposits, alluvial plains, and diluvial terraces. The mean values of soil pH ranged 5.7~5.8 that were within optimal range for rice cultivation. The mean values of other properties such as soil organic matter (SOM) content, the concentrations of exchangeable cations, $K^+$, $Ca^{2+}$, and $Mg^{2+}$, and available silicate concentration were lower or close to the optimal values, but the mean concentrations of available phosphorus were exceeded the range of optimal value, $80{\sim}120mg\;kg^{-1}$, in many paddy fields. In particular, The concentrations of available phosphorus in the paddy fields of local valley and fans, alluvial plains, and fluvio-marine plains were mostly declined. However, in diluvial terrace areas, the phosphorus concentrations unexpectedly increased; furthermore, they were significantly higher than those in other topographic areas. The mean concentrations of 0.1 M HCl-extractable heavy metals, Cd, Cr, Pb, Cu, Ni, and Zn, in the paddy fields were slightly and gradually declined during the study years, but the Pb concentrations were not statistically changed. In addition, the concentrations of heavy metals were widely ranged depending on the different sampling sites. Nevertheless, the concentrations of heavy metals were significantly lower than the levels of Soil Contamination Warning Standard (SCWS) for agricultural lands (1-region) presented in Soil Environment Conservation Law (SECL).

Chemical Weathering of Hornfels Pebbles in the Marine Terrace Deposits, Yangnam-Myon, Gyeongju (경주시 양남면 제4기 해안단구퇴적층내 혼펠스 자갈의 화학적 풍화작용)

  • 정기영;이봉호
    • Journal of the Mineralogical Society of Korea
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    • v.17 no.1
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    • pp.85-97
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    • 2004
  • Weathering of hornfels pebble in the marine terrace deposits, Yangnam-Myon, Gyeongju was investigated by X-ray diffraction, scanning electron microscopy, and chemical analysis. In the early stage of weathering, only plagioclase was leached leaving pores. With progress of weathering, biotite and chlorite were tranformed to hydrobiotite and chlorite-vermiculite, respectively. Quartz, K-feldspar, and muscovite were not altered. Thickness of weathering rinds and their mineralogical characteristics were different between terraces of different elevations. In the lower second terrace, the weathering of pebble was dominated by the decomposition of plagioclase, while in the upper third terrace, weathering was characterized by the transformation of biotite and chlorite with precipitation of halloysite from the weathering of plagioclase. Thickness of weathering rind and weathering products were varied even within the same terrace deposit probably due to local variation of drainage conditions.

Crustal Uplift and Microseismic Activity around Syowa Station, Antarctica

  • Kaminuma, Katsutada
    • Ocean and Polar Research
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    • v.24 no.3
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    • pp.249-253
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    • 2002
  • There is a great deal evidence concerning crustal uplift, after deglaciation, in the vicinity of Syowa Station $(69^{\circ}S,\;39^{\circ}E)$ from tide gauge data, seismic evidence, raised beaches, marine terraces, etc. The geomorphological and tide gauge data show that the crustal uplift is going on around Syowa Station. Seismic observations at Syowa Station started in 1959. Phase readings of the earthquakes have been published by National Institute of Polar Research once a year since 1968, as one of the Data Report Series. Eighteen local earthquakes were detected on short period seismograms at Syowa Station in 1990-2000. The seismicity during the period from 1990 to 2000 was lower than that from 1987 to 1989 when epicenters of local earthquakes were determined by tripartite seismic array. Local earthquake activity corroborates the crustal uplif4 which is an intermittent phenomenon. Sea level falling of 4.5 mm/y was found using data in 1975-1992. This felling rate is consistent with the geomorphological data. A route for repeat leveling survey was established in East Ongul Island. No appreciable change of sea level was observed for the last 14 years. A dynamics of the crustal uplift around Syowa Station has been discussed using geomorphological data, ocean tide, and seismic and leveling data, which is estimated to be an intermittent phenomenon. When local seismic activity is high, the crustal uplift is estimated to be going on. On the contrary, the crustal uplift is in dormancy when the local seismicity is low. Repeated leveling measurements suggest no significant changes, which further supports the idea that the crustal uplift in offshore is not a tilt trend movement but a block movement.

Superconducting properties of layer-by-layer grown $YBa_{2}Cu_{3}O_{7}$ thin film prepared by pulsed laser deposition (펄스 레이저 증착법으로 layer-by-layer 성장시킨 $YBa_{2}Cu_{3}O_{7}$ 박막의 초전도특성)

  • Kim, In-Seon;Lim, Hae-Ryong;Kim, Dong-Ho;Park, Yon-Ki;Park, Jong-Chul
    • Journal of Sensor Science and Technology
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    • v.7 no.1
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    • pp.61-66
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    • 1998
  • High quality c-axis oriented $YBa_{2}Cu_{3}O_{7}$ films were prepared using the pulsed laser deposition on $SrTiO_{3}$(100) substrate. The atomically smooth $SrTiO_{3}$surface with terraces one unit cell in height could be obtained by a high temperature annealing. $YBa_{2}Cu_{3}O_{7}$ thin films deposited on the substrates exhibited layer-by-layer growth with a c-axis unit cell height. $YBa_{2}Cu_{3}O_{7}$ thin films thus prepared showed critical temperature ${\ge}90$ K with transition width ${\le}0.6$ K, room temperature resistivity of ${\sim}300{\mu}{\Omega}cm$, and critical current density ${\sim}4.6{\times}10^{6}A/cm^{2}$ at 77 K.

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Effects of Forest Environmental Factors and Forest Road Structures on the Stability of Forest Road in Granite Areas (화강암지역의 산림환경 및 도로구조인자가 임도의 안정성에 미치는 영향)

  • Yim, Byung-Jun;Ma, Ho-Seop
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.2 no.3
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    • pp.83-92
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    • 1999
  • To investigate the influence of forest road characteristics and site conditions on the stability of forest-road in granite area, four forest roads had been selected in Kyongbuk regions. The total of 13 road characteristic variables were evaluated by the discriminant analysis. The factors influencing the stability of forest road were bed rock, slope length, coverage, hardness, side-ditch erosion and road width. But aspect and soil texture were not significant for the stability in this area. In the correlation between forest environment and road structure, hardness and bed rock was highly significant in stability group, and coverage and side-ditch erosion was highly significant in instability group. 75 of 175 segments were instable whereas the others were stable. The centroids value by discriminant function in the stability and instability were estimated to 3.0585 and -1.9116, respectively. The stability criterion of forest road was discriminated from the centroids value of the each group. The main factors contributing the stability of forest road were significant in order of side-ditch erosion, coverage, soil texture, elevation, gradient, slope length and construction year. The prediction rate of discriminant function for stability evaluation of forest road was as high as 97.44%. In conclusion, the forest road structure factors such as length, coverage and slope gradient were controlled by construction techniques. If the factors like those should be considered in design, construction and forest road management, the stability of forest road may increase more. And also, it is necessary to take slope protection measures like small terraces and retaining walls for stability of cut slope.

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Properties of Channel and Evolutions of Fluvial Terraces in Odae River (오대천의 특성과 하안단구의 형성과정)

  • Lee, Gwang-Ryul
    • Journal of the Korean Geographical Society
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    • v.44 no.3
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    • pp.224-239
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    • 2009
  • This study analyzes the properties of fluvial landforms in the upper and lower reaches and investigates the evolutions of stream and fluvial terrace in the Odae river basin. The lower basin of the river that consist of sedimentary rocks resistant to weathering and erosion processes shows higher altitude, relief and slope than the upper basin that consist of granite less resistant to weathering and erosion processes. The average width of river valley at the lower reaches is one-third to the upper reaches and the average width of river channel at the lower reaches is narrower than at the upper reaches. Based on the OSL age dating, the fluvial terrace T1 formed at the temperature-rising period during the late MIS 2 and T2 formed at the middle MIS 3, interstadial period during the last glacial period. Based on the these results, the average incision rates of Odae river are calculated as 0.205m/ka and 0.269m/ka at the upper granite area and lower sedimentary rocks area, respectively.

A Study on the meaning Hundertwasser's architecture in the modern Society (현대 사회에서 갖는 훈데르트바써(Hundertwasser) 건축의 의미)

  • 유연숙
    • Korean Institute of Interior Design Journal
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    • no.8
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    • pp.3-15
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    • 1996
  • Friedensreich Hundertwasser , born in Vienna 1928, is a painter, an architect and an environmentalist. His architecture is radically different from the traditional , straight -lined, functional architecture practised, for example, by the Bauhaus Masters. From the very beginning , he has tried by various means to show that radical change in thinking are necessary , possible and realized. Hundertwasser's goal in this architecture is to make and give human dwelling in harmony with nature. his architecture is characterized by avoidance of straight lines, " Window Right", irregular arrangement of windows, onion dom, a wealth of colours and such environmentally -friendly consideration as planting of roofs and realizing of "tree-tenants". hundertwasser sees houses as evolving creations which are to be shaped by their inhabitants. He hates Uniformity. The irregularity is always the guiding principle in his architecture. The Hundertwasser's architeucture express his fundamental belief that we may not simply rob nature of her resources, but that we must also return territory to nature which we habe stolen from her. Roofs, terraces and courtyards planted with vegetation and " tree-tenants" build bridges between man and nature. They influse the architecture with vitality and romanticism and are a statement of a quality rather than a standard of living. It is quite possible to value the architecture of Hundertwasser as an important inspiration, as a sort of turning point in the thoughts and actions of city planners. It's success could be healing shock for the international architectural community, which is hypnotized by technology and abused by the shortsighted interests of ren.tability . Under this pressure, today's architects trend to reduce people to a mere part of the " Dwelling machine", without acknowledging that in the long run such machines eat away at people's souls.uch machines eat away at people's souls.

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Geomorphic development and distributional system of marine terrace in the eastern part of Seopo-myeon, Sacheon-si, Gyeongnam Province (경남 사천시 서포면 동쪽 해안단구 지형 발달과 분포 체계)

  • Yoon, Soon-Ock;Kang, Bong;Park, Chung-Sun;Hwang, Sangill
    • Journal of the Korean association of regional geographers
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    • v.22 no.4
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    • pp.875-886
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    • 2016
  • The eastern coast of Seopo-myeon, Sancheon-si in the South Coast is a bay almost completely separated from open sea by Changseon and Namhae Islands. Marine terraces in this area can be classified into geomorphic surfaces with elevations of 10~12m, 15~18m, 20~24m, 25~28m, 30~33m, 35~38m, 40~45m, 45~50m and 54m. This marine terrace system is similar to the Boryeong area in the West Coast. The geomorphic surfaces distribute along ridges and show relatively small areas. The young and old surfaces show a mixed distributional pattern. This distributional pattern contrasts to the East Coast where the oldest surface farthest from the coastline is parallel to the coast and age of the surfaces increases with a distance from the coast. These seem to result in high energy waves by typhoon that developed wave-cut platform on hill areas with relatively complex relief in a short time.

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