• Title/Summary/Keyword: 사면토양

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Reflection and perspective of the geomorphology in Korea (한국 지형학의 50년 회고와 전망)

  • ;Oh, Kyoung-Seob
    • Journal of the Korean Geographical Society
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    • v.31 no.2
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    • pp.106-127
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    • 1996
  • In Korea, modern geomorphology has developed as one of main subjects in geography, such as in Europe. Geomorphology is one of the most advanced specialties in the geography dicipline, since foundation of Korean Geographical Society in 1945. Untill 1960's study, first generation of the Korean geomorphologists trained the younger ones, together with energetic research activities. Their great works in education and research established the base of ulterier development of the geomorphology in Korea. Since 1970s, research manpower and quality has incresed rapidly, partly due to the various international activities and cooperations of Korean geomorphologists. Owing to above development, Korean geomorphologist was able to found "The Geomorphological Association of Korea" in 1990 and publish "Journal of GAK", since 1994. Furthermore, geomorphologists are playing important roles in interdisciplinary academic societies, such as "The Korean Quaternary Assocition". Still 1960s, our research had focused on the identification and interpretation of erosional surfaces in Korea Peninsular. Of course, W.M. Davis's "Geographical Cycle Theory" and L.C. King's "Pedimentation Theory" had a great influence on the Koerans' works. After 1970s, the study of erosional surface played the important role in setting up the morphoclimatic viewpoint and methodology. Research scope tend to be notably broad and various than it was untill 1960's. Disposotion of the scientific methods and techniques become more and more apparent. These trends of research has settled precise descreption and interpretation of actual landforms, based on the careful field works, scientific measuring, and analisis, rather than methodology focused on the particular master theories. Recent geomorphological researches show the scope from climatic geomorphology and Quaternary geomorphology to granite and limestone weathering, pedo-geomorphogenic environment and periglacial landforms, focused on the small-to-medium scales. And then there have been new trying to interprete erosional surfaces such as hillslopes and terraces. Also, studies of coastal and plain landforms have been successfully developed. Recent new trends show the quantitative and analytic modelling using field measurement and laboratory work, and study on the human impacts on the natural landforms.y on the human impacts on the natural landforms.

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Flora of middle part in Gyeonggi Province (경기도 중부지역의 식물상)

  • Ko, Sung-Chul;Shin, Young-Hwa
    • Korean Journal of Plant Resources
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    • v.22 no.1
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    • pp.49-70
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    • 2009
  • Floral study on the vegetation of 8 mountains including Taehwa-san, Mugab-san, Haehyeob-san, Guksa-bong, Gwanggyo-san, Samseong-san, Suri-san, and 200m peak neighboring to Mulwang lake was carried out from April to October, 2007. They belong to the middle part of Gyeonggi Province, and located between Lat. $37^{\circ}$13' 31.19" ${\sim}37^{\circ}$33' 3.48", Long. $26^{\circ}$43' 04.1" ${\sim}127^{\circ}$26' 28.38". Vascular plants collected in these areas were total 447 taxa composed of 386 species, 5 subspecies, 46 varieties and 10 forms of 262 genera under 92 families. The area from which the most plentiful plants were found was Mt. Gwanggyo-san. The areas with comparatively excellent vegetation are easy slopes nearby valleys in Mt. Gwanggyo-san, Mt. Suri-san and Mt. Haehyeob-san. Forests of the examined areas are generally mixed of Pinus densiflora and Quercus plants, but herbaceous plants covering soil are becoming nearly extinct by air and soil pollutions except some sites. Families with abundant species are Compositae, Rosaceae, Liliaceae and Graminae, etc. Endemic plants found in these areas are 8 taxa of Clematis brachyura, Euonymus trapococcus, Viola seoulensis, Ajuga spectabilis, Scutellaria insignis, Weigela subsessilis, Aster koraiensis, Aconitum chiisanense and rare and endangered plants are 7 taxa of Arisaema heterophyllum, Iris odaesanensis, Eranthis stellata., Aconitum chiisanense, Prunus yedoensis (cultivar), Viola albida, and Syringa wolfi. As to useful plants, 192 taxa for the edible, 132 taxa for the medicinal, 130 taxa for the ornamental and 11 taxa for the staining were classified respectively. Among 17 taxa of specially designated plants, 5th degree plants are 2 taxa of Iris odaesanensis and Prunus yedoensis (cultivar), 4th degree plants are 2 taxa of Symplocarpus renifolius and Syringa wolfi, 3rd degree plants are 13 taxa of Dryopteris gymnophylla, Juniperus chinensis, Betula chinensis, Betula davurica, Diarrhena fauriei, Aconitum longecassidatum, Eranthis stellata, Spiraea salicifolia, Acer palmatum, Vaccinium koreanum, Scutellaria insignis, Weigela florida and Adoxa moschatellina.

On the Construction of Embankment of the Eui-Rim Reservoir (의림지(義林池) 축제(築堤)에 관(關)한 일고찰(一考察))

  • Chung, In Koo
    • Journal of Korean Society of Forest Science
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    • v.23 no.1
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    • pp.29-33
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    • 1974
  • U-Reuk, a laureate musician in the days of King Jin-Heung, Silla Dynasty, built the Eui Rim Reservoir about 1,400 years ago. This was one of the oldest man-made reservoir. The embankment of the reservoir collapsed by the clumsy artificial drainage on August 19, 1972 when the heavy rainfall of 462 mm/day caused a dangerous overflow of the reservoir. The result of the study on the mystic ancient embankment techniques are as follows: 1. Sandy loam derived from the weathering of granite which is the most widely distributed rock type in the area, was used in the embankment. Large size logs (embankment core) of 30-50 cm in diameter were buried lengthwise along the embankment. 2. The six stocks of Pinus densiflora, 3 stocks of Quercus acutissima, 1 stock of Quercus variabilis and 1 stock of Popolus maximowiczii, altogether 11 stocks are identified. Forest types in the nearby area during the days of the reservoir construction seem to be includde a considerable number of Pinus densiflora, Quercus and Populus species. 3. The angle of repose of the earth materials is taken into account during the embankment. On top of the embankment double layers of clay (20-30 cm indepth) were spread and consolidated. Layer of litter of 20-40 cm in deep covered on the clay layer of the embankment completely, and another layer of clay was consolidated over the litter. Finally, a layer of stones of 10-30 cm in diameter and clay (yellow soil layer) toped the embankment. 4. At the lower part of the embankment clay layer was thicker and became thinner as it goes upwards. At every layer, soil was consolidated and burned. When embankment was completed, it was covered evenly with heavy clay, and finally it was topped with general soil. 5. The heavy clay layer on the inner slope of the embankment showed gray phenomena and litter remained raw humus layer. The clay layer functioned as rubber in the water, and raw humus layer prevented water from seepages. Thus, the embankment was solidly built in this way. 6. The ancient embankment techniques used soils conveyed from nearby area taking the angle of repose into account. Once embankment was completed, clay and litter layers were added to have a plasticity and to withstand the water pressure. 7. It is an excellent technique that the reservoir was constructed with least labor for maximum effects while the recent embankment techniques requires a large amount of labor.

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Geomorphic Features of Bing-gye Valley Area(Kyongbuk Province, South Korea) -Mainly about Talus- (의성 빙계계곡 일대의 지형적 특성 -테일러스를 중심으로-)

  • Jeon, Young-Gweon
    • Journal of the Korean association of regional geographers
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    • v.4 no.2
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    • pp.49-64
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    • 1998
  • Bing-gye valley(Kyongbuk Province, South Korea) is well known as a tourist attraction because of its meteorologic characteristics that show subzero temperature during midsummer. Also, there are some interesting geomorphic features in the valley area. Therefore, the valley is worth researching in geomorphology field. The aim of this paper is to achieve two purposes. These are to clarify geomorphic features on talus within Bing-gye valley area, and to infer the origin of Bing-gye valley. The main results are summarized as follows. 1) The formation of Bing-gye valley It would be possible to infer the following two ideas regarding the formation of Bing-gye valley. One is that the valley was formed by differential erosion of stream along fault line, and the other is that the rate of upheaval comparatively exceeded the rate of stream erosion. Especially, the latter may be associated with the fact that the width of the valley is much narrow. Judging that the fact the width of the valley is much narrow, compared with one of its upper or lower valley, it is inferred that Bing-gye valley is transverse valley. 2) The geomorphic features of talus (1) Pattern It seems to be true that the removal of matrix(finer materials) by the running water beneath the surface can result in partly collapse hollows. Taluses are tongue-shaped or cone-shaped in appearance. They are $120{\sim}200m$ in length, $30{\sim}40m$ in maximum width. and $32{\sim}33^{\circ}$ in mean slope gradient. The component blocks are mostly homogeneous in size and shape(angular), which reflect highly jointed free face produced by frost action under periglacial environment. (2) Origin On the basis of previous studies, the type of the talus is classified into rock fall talus. When considered in conjunction with the degrees of both weathering of blocks and hardness of blocks, it can be explained that the talus was formed under periglacial environment in pleistocene time. (3) The inner structure of block accumulation I recognize a three-layered structure in the talus as follows: (a) superficial layer; debris with openwork texture at the surface, 1.3m thick. (b) intermediate layer: small debris(about 5cm in diameter) with fine matrix(including humic soil), 70cm thick. (c) basal layer: over 2m beneath surface, almost pure soil horizon without debris (4) The stage of landform development Most of the blocks are now covered with lichen, and/or a mantle of weathering. It is believed that downslope movement by talus creep well explains the formation of concave slope of the talus. There is no evidence of present motion in the deposit. Judging from above-mentioned facts, the talus of this study area appears to be inactive and fossil landform.

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