• Title/Summary/Keyword: 풍화토양

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Landscape of Erosional Basin in Korea -In case of land-use changes of hills- (우리 나라 침식분지의 경관 -구릉지의 토지이용 변화를 중심으로-)

  • Son, Myoung-Won
    • Journal of the Korean association of regional geographers
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    • v.6 no.2
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    • pp.83-96
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    • 2000
  • Erosional basins formed in middle and upper reaches of Korean great rivers have been main life space of local small and middle cities, but previous studies on erosional basins are widely apart from residents' life and are in shortage with the endeavor to elucidate the man and environment relationship. This paper analyzes the factors and the modes of land-use changes of hills in the erosional basin. In this paper four erosional basins with different geological conditions are selected to elucidate the effect of geological factor(Geochang: granite, Chogye: metamorphic rock, Angye: gravelly sedimentary rock, Maseong: limestone). And the distribution of land use on the transverse and longitudinal cross-section map of the hill is described. The landscape of erosional basin is consisted of surrounding mountains, hills, dissected valleys, and incoming river's floodplain. Dissected valleys and incoming river's floodplain were reclaimed early as paddy field and hills have been used as woodland up to recently. Residents have a new appreciation of hills as a productive hill out of a traditional holy space[mountain] by influence of capitalistic thought that 'natural environment is a sort of productive resource'. Population increase is the another pressure of hill reclamation. The modes of landscape changes due to natural conditions are as follow: (1) In Geochang basin with dense tectolineament spacing, the gentle part of hill is used as field, orchard and agricultural-industrial complex site and the steep part is as woodland. (2) Hills in Angye basin with sparse tectolineament spacing are relatively flat because of maintaining a part of original denudational surface, and are used as orchids, field, paddy fields and agricultural-industrial complex site. The dissection valleys between hills are gentle concave and are used as paddy fields. (3) Hills in Maseong basin are wide and flat, and are used as fields, orchards, and agricultural-industrial complex site. (4) Because hills in Chogye basin, a closed type, are weared by affluents and are narrow and short. Hills are used as woodland and wide dissected valleys are reclaimed as paddy fields.

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Characteristic Assessment of Heavy Metals in Dusts Collected by the Air Filtration System at Subway Stations in Daegu, Korea (대구지역 지하철역사 공기여과필터 포집먼지에 함유된 중금속성분의 특성평가)

  • Do, Hwa-Seok;Song, Hee-Bong;Shin, Dong-Chan;Kwak, Jin-Hee;Lee, Myoung-Sook;Yoon, Ho-Suk;Kang, Hye-Jung;Phee, Young-Gyu
    • Journal of Korean Society of Environmental Engineers
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    • v.31 no.1
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    • pp.42-50
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    • 2009
  • Samples of subway dust were collected by the air filter system of 30 subway stations on Daegu subway line 1 in January 2008. Samples were sieved below 100 ${\mu}m$, and 14 elements were analyzed using ICP after acid extraction. Results obtained from the source assessment of trace elements using enrichment factor showed that Ca, Fe, K, Mg, Mn, Na, V were influenced by natural sources such as weathered rock and resuspended soil, while Cd, Cr, Cu, Ni, Pb and Zn were influenced by anthropogenic sources such as fuel combustion and waste incineration. Concentrations were remarkably higher in components from natural sources than in components from anthropogenic sources. Anthropogenic sources were significantly affected by indoor dusts than outdoor dusts. Results of pollution indices of heavy metals indicated that indoor dusts were more contaminated with heavy metal ions than outdoor dusts. The correlation analysis among trace elements indicated that components were much correlated in the order of natural sources-anthropogenic sources, anthropogenic sources-anthropogenic sources, natural sources-natural sources in both indoor and outdoor dusts. Trace element components of outdoor dusts were largely correlated than those of indoor dusts. In addition, indoor dusts were significantly affected by outdoor dusts rather than depth from the surface or the average daily number of subway passengers.

Physico-Chemical Properties of Aggregate By-Products as Artificial Soil Materials (골재 부산물의 용토재 활용을 위한 특성 분석)

  • Yang, Su-Chan;Jung, Yeong-Sang;Kim, Dong-Wook;Shim, Gyu-Seop
    • Korean Journal of Soil Science and Fertilizer
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    • v.40 no.5
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    • pp.418-428
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    • 2007
  • Physical and chemical properties of the aggregate by-products including sludge and crushed dust samples collected from the 21 private companies throughout the country were analyzed to evaluate possible usage of the by-products as artificial soil materials for plantation. The pH of the materials ranged from 8.0 to 11.0. The organic matter content was $2.85g\;kg^{-1}$, and the total nitrogen content and available phosphate content were low as 0.7 percents and $12.98mg\;kg^{-1}$, respectively. Exchangeable $Ca^{2+}$, $Mg^{2+}$, $K^+$, and $Na^+$ were 2.29, 0.47, 0.02 and $0.05cmol\;kg^{-1}$, respectively. Heavy metal contents were lower than the limits regulated by environmental law of Korea. Textural analysis showed that most of the materials were silt loam with low water holding capacity ranged from 0.67 to 7.41 percents, and with low hydraulic conductivity ranged from 0.4 to $2.8m\;s^{-1}$. Mineralogical analysis showed that the aggregate by product materials were mostly composed of silicate, alumina and ferric oxides except calcium oxide dominant materials derived from limestones. The primary minerals were quartz, feldspars and dolomites derived from granite and granitic gneiss materials. Some samples derived from limestone material showed calcite and graphite together with the above minerals. According to the result, it can be concluded that the materials could be used as the artificial soil material for plantation after proper improvement of the physico-chemical properties and fertility.