• Title/Summary/Keyword: materials of sanddune

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Studies on the Desertification Combating and Sand Industry Development(IV) - Technology Development for Sanddune Fixation and Sandy Land Conservation in China - (사막화방지(沙漠化防止) 및 방사기술개발(防沙技術開發)에 관한 연구(硏究)(IV) - 중국(中國)의 사구고정(沙丘固定) 및 방사공법분석(防沙工法分析) -)

  • Woo, Bo-Myeong;Lee, Kyung-Joon;Choi, Hyung-Tae;Lee, Sang-Ho;Park, Joo-Won;Wang, Lixian;Zhang, Kebin;Sun, Baoping
    • Journal of Korean Society of Forest Science
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    • v.90 no.3
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    • pp.277-294
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    • 2001
  • This study is aimed to analyze and to evaluate the technology development for sanddune fixation and sandy land conservation in China, resulting from the project of "Studies on the desertification combating and sand industry development". There are various types of sanddunes, including shrub-bunch type, dendritic, honey combed lattice, crescentic, parabolic, pyramid, complex and irregular types, domed, and so on. The height distribution ratios of these sanddunes are 13% of less than 5m, 17% of 6~10m, 18% of 11~25m, 14% of 26~50m, 28% of 51~100m, 10% of more than 100m, and so on. In dry land of China, shifting direction of the sanddune is mainly varying with main direction of wind, but types of shifting sanddunes have many differences in accordance with region, topography, size and shape of sanddunes. The main sanddune fixation technologies could be divided into the bio-ecological measures, physical measures and chemical measures. The bio-ecological measures include such vegetation measures as shrub-grasses measures, sandbreaks between sand dunes, sand fixation shelterblets and establishment of farmland shelterbelts, etc. The physical measures include establishment of high-sanddune stabilization walls and low-sanddune stabilization walls, sanddune fixation levees and coverage method with sediment clay, etc. The chemical measures include fixation-materials spraying and synthetical liquid spraying methods, etc. Besides, irrigation and sand settlement measures, shifting sand trapping channel, ditchsand fixation measures, etc. have been effectively applied.

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Beach and Sanddune Development along the Coastline of the Chungcheong-Namdo Province (충청남도 해안에 발달한 해빈과 해안사구)

  • Kahng, Tay-Gyoon
    • Journal of the Korean earth science society
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    • v.24 no.6
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    • pp.568-577
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    • 2003
  • The purpose of this paper is to examine the geomorphic processes of beach and sanddune development in the Chungcheong-Namdo Province. The sands consist mainly of quartz and feldspar with lesser amounts of mica and other heavy minerals. With the exception of those from the granite, the sands have a very fine texture. Another characteristic of the sand grains is low degrees of roundness and grading indicating that source areas for the material were in the vicinity of the accumulating field. Over the years, the beaches have receded as a response to the decreasing amount of depositional materials. The driving force for the formation and transformation of coastal dunes in the study area is dominant winds from the center of the Siberian High. To some extent, the erosion of coastal dunes has been a global phenomenon. The degradation process occurred most actively when spring tides attacked beaches, berms, and foredunes. The relief and shape of present-day coastal dunes is determined initially by the Pleistocene strata underneath. From the fact that the strata contained traces of frozen structure, it can be inferred that sediment once experienced the process of soil formation.

The Origin of Coastal Dunesand in the Chungcheongnam-do (해안사구의 물질 구설과 플라이스토세층 - 충청남도의 해안을 중심으로 -)

  • 강대균
    • Journal of the Korean Geographical Society
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    • v.38 no.4
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    • pp.505-517
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    • 2003
  • The purpose of this paper is to examine the origin of materials of sanddune in the Chungcheongnamdo. The sands consist mainly of quartz with lesser amount of feldspar and other heavy minerals. With the exception of those from the granite, the sands have a very fine texture. Another characteristic of the sand grains is the low degrees of roundness and grading which indicates that the source areas of the material are not far from the accumulating field. The rivers and streams of this region are not effective in transporting sediments for the coastal dunes. It has been recognized that the beaches and sanddunes have recently been receded as a result of the decrease in materials and the devastating actions of the breakers. The degradation process occurs most actively when the spring tides attack the beaches and foredunes. There are strata with red tint along the coastal areas of the Chungcheongnamdo which trace their origin back to the Pleistocene. From the fact that they contain little or no gravels, the strata are believed to have been the sanddunes during the last interglacial period. This fossil dunes provide part of the materials for the development of the present-day sanddunes along the coastal areas of the region.