• Title/Summary/Keyword: 토양발달

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Root Morphology of Norway Spruce (Picea abies [L.] Karst.) in the Differently Acidified Forest Soils (토양(土壤) 산성화(酸性化) 정도(程度)에 따른 독일가문비나무(Picea abies [L.] Karst.))

  • Lee, Do-Hyung
    • Journal of Korean Society of Forest Science
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    • v.89 no.5
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    • pp.677-684
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    • 2000
  • This study was conducted to investigate the relationship of development of root and soil condition and also to elucidate the difference between stands for mechanical and physical stability according to distribution of roots in the Norway Spruce (Picea abies [L.] Karst.) stands of 30 to 40 year of ages with different soil condition. In the root structure, remarkably different root pattern was shown among the three stands; Eberg$\ddot{o}$tzen stand showed large number f roots with much fine roots which deeply in vertical direction while Barbis stands had thicker root and small number of root than Eberg$\ddot{o}$tzen stand. The Weidenbrunnen stand showed differently half-vertical and plate root structure and the root developed not to be deeply compared to the other two stands. In the total number of root, Eberg$\ddot{o}$tzen stand had the most number of 74 and Barbis stand 33, Weidenbrunnen stand 57 respectively. Eberg$\ddot{o}$tzen stand had much more number of vertical root with 57 than the other two stand; Barbis 21 and Weidenbrunnen 36. In the total length of root, Weidenbrunnen stand showed to be longer than the other two stands and the length of horizontal root also showed longer. Regarding to the rates of horizontal root against vertical root, Eberg$\ddot{o}$tzen stand showed comparatively higher value as 1,2 than other two stands(0.5). In the total weight of root, Weidenbrunnen stand showed very high value compared with the other stands and ratio of vertical root against horizontal root was 0,16 which is very lower than the other two stands(0,4). The remarkable differences of root pattern of Norway spruce stands appeared in this study are through to be caused more by chemical property of soil such as acidity den the mechanical or physical factor of soil conditions.

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Sediment Delivery Ratio in the Burnt Mountain Areas according to Watershed Size (유역의 크기에 따른 산불지역 토사유출률)

  • Shin, Seung-Sook;Park, Sang-Deog;Chae, Kuk-Sheok;Song, Bum-Ho;Lee, Cheol-Kyu
    • Proceedings of the Korea Water Resources Association Conference
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    • 2006.05a
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    • pp.1556-1560
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    • 2006
  • 유역 전체의 토양침식량에 대한 토사유출량의 비로 정의되는 토사유출률은 유역의 크기가 커지면 토사가 유출되는 과정에서 퇴적되거나, 저류될 수 있는 지형적인 요인이 많아지게 되어 상대적으로 감소한다. 우리나라 산불지역의 유역에 대량의 토사유출을 제어하기 위해 설치된 여러개의 사방댐을 활용하여 강우사상별 댐 저류지에 퇴적되는 토사량 측정하였다. 실측된 토사유출량과 산지사면을 대상으로 개발된 토양침식 모형인 SEMMA에 의해 예측된 토양침식량과를 비교하여 유역크기에 따른 토사유출률의 관계를 분석하였다. SEMMA는 강우에 의한 토양입자의 분리현상과 지표유출에 의한 세류와 세류간 침식에 의해 발생하는 토양침식량을 산정하지만, 구곡이나, 유역의 수로에서의 침식은 고려하지 않는다. 보편적으로 토사유출률은 1.0을 넘지 않으나, 본 연구에서는 토사유출률이 대부분 1.0을 넘는 결과를 보여 산불 지역의 유역에서는 수로발달과 수로확장에 의한 침식이 심각했다. 토사유출률이 산지 유역이 커짐에 따라 감소하는 경향은 세계의 다른 유역에서의 조사된 결과와 비슷한 결과를 보였으나, 수치적인 차이가 큼을 알 수 있었다. 또한 토사유출률은 강우사상의 크기에도 상관성이 있음이 확인되었다.

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A Study on Attenuation of Ground Vibration Using Hammer Generated Seismic Wave (탄성파탐사에 의한 토양층 지반진동의 감쇠연구)

  • 서만호;손호웅
    • The Journal of Engineering Geology
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    • v.6 no.2
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    • pp.95-102
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    • 1996
  • A study on the attenuation of ground vibration was carried out on the soil layer using seismic exploration method. A 12-channel engineering seismograph was used to acquire real digital amplitude data in field work. Frequency analysis of seismic data shows maximum spectrum amplitude around 40Hz. Relative amplitude decreases exponentially as the distance increases and the attenuation factors are n = 0.25 and a = 0.13-0.20. Internal attenuation indexes(a) are 0.13 and 0.20 in the wet soil zone and the vegatated soil zone, respectively. It means that ground vibration attenuates faster in vegatated soil zone than in wet soil zone. Average internal attenuation coefficient(h) was determined to be 0.094 from seismic velocity and frequency analysis.

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Effect of Organic Material Treatments on Soil Aggregate Formation in Reclaimed Tidelands (유기물 처리가 간척지 토양의 입단형성에 끼치는 영향)

  • Son, Jae-Gwon;Cho, Jae-Young
    • Korean Journal of Soil Science and Fertilizer
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    • v.42 no.3
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    • pp.201-206
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    • 2009
  • It is generally accepted that organic materials are a significant factor on the soil aggregation formation but little information exists on how the formation and stabilization of aggregates in reclaimed tidelands. In this work, the effects of organic materials on the soil aggregate formation in reclaimed tidelands were determined. The soil was treated with 5 cm-size chopped fresh italian ryegrass residues (fresh organic material), commercial livestock compost with swine manure and sawdust (by product fertilizer), and fresh organic material + by product fertilizer (1 : 1 w/w) after ploughing at 20 cm soil depth. The three organic materials applied $2,000kg\;10a^{-1}$ every year. Water stable aggregate was estimated by wet-sieving method. Three years after the beginning of the experiment, water stable aggregate rate and MWD (mean weight diameter) were higher fresh organic material treatment than two other treatments. For improvement of physical property and structure of soil in reclaimed tidelands, fresh organic material treatment was more suitable than two other treatments.

Changes in Soil Physicochemical Properties and Dehydrogenase Activity by the Formation of Fairy Ring of Tricholoma matsutake (송이 균환(菌環)의 발달(發達)에 따른 토양(土壤)의 이화학적(理化學的) 특성(特性)과 탈수소효소(脫水素酵素)의 활성(活性) 변화(變化))

  • Huh, Tae-Chul;Park, Hyun;Chung, Jin-Hyun;Joo, Sung-Hyun
    • Journal of Korean Society of Forest Science
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    • v.87 no.2
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    • pp.270-275
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    • 1998
  • The management of pine-mushroom forest means the environmental control for fairy ring of Tricholoma matsutake. Thus, the management demands intensive study for keeping healthy condition of the fairy ring, and that for the measurement of active portion of the soil ecosystem. This study was conducted to investigate the impact of T. matsutake fungus on the soil physicochemical properties and dehydrogenase activity by dividing the fairy ring into 3 regions such as 'zone of decayed mycorrhizae', 'zone of physiologically active mycorrhizae', and 'in front of fairy ring'. The passing of T. matsutake did not result in significant changes in canon contents of soils, but available phosphorus, carbon, and nitrogen contents were different between the soils of active mycorrhizal zone and that in front of fairy ring. The dehydrogenase activity around the fairy ring of T. matsutake was quite lower than that in general forest soils, which indicated that the fairy ring of T. matsutake was built up in the relatively immature soils which contain little organic matter. Thus, the dehydrogenase activity of soil was thought to be used as an index for the management of pine-mushroom forest with considering that the management practically means the environmental control for keeping good conditions for the development of fairy ring of T. matsutake. Especially, the dehydrogenase activity measurement can be recommended as a tool for time-decision of litter removal by floor raking since the activity is a good index of litter decomposition.

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Changes of Vegetation Structure according to the Hydro-seral Stages in the East Coastal Lagoons, Korea (동해안 석호에서 수생천이계열에 따른 식생구조의 변화)

  • Kim, Hyoe-Young;Kim, Mi-Hee;Choi, Hee-Kyung;Lyang, Doo-Yong;Shin, Eun-Joo;Lee, Kyu-Song;Yi, Hoon-Bok
    • Journal of Wetlands Research
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    • v.12 no.3
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    • pp.129-144
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    • 2010
  • We have studied the changes of the environmental and vegetational factors according to the hydro-seral stages in the shoreline of the lagoons, Korea. We have divided seral stages into 7 stages from open water stage to the stratified forest stage considering as the characteristics of water body, dominance of submerged and emergent plant, and development of the shrub, subtree and tree layer. According to the successional stage, water depth gradually decreased and water quality changed from seawater to brackish water and from brackish water to fresh water, organic matter in a soil layer gradually increased, and the litter layer grew up. As the development of the vegetation structure, the life-form of the vascular plants changed as follows; open water ${\rightarrow}$ submerged plant and floating-leaved plant ${\rightarrow}$ emergent plant and submerged plant ${\rightarrow}$ emergent plant ${\rightarrow}$ emergent plant, mesophyte and scrub ${\rightarrow}$ mesophyte. In the late seral stage, the 3 different forest types were established by the water retention or drainage and nutrient accumulation of the soil layer. Salix dominant forest developed in the wetted sites, the forest type dominated by Pinus thunbergii, Carex pumila and mesophytes developed in the well drained sites causing by sand substrate, and the forest type dominated by the planted or ruderals such as Pinus densiflora, Robinia psedo-acacia, Festuca ovina, Setaria viridis ect. developed in the sites composed of forest soil introduced by artificial reclamation.

Assessment of runoff and sediment yield of So-Okcheon watershed using SWAT model and GeoWEPP model considering hillslope hydrological concept (SWAT 모형과 hillslope hydrological 개념의 GeoWEPP 모형을 이용한 소옥천 유역의 유출 및 토사유출량 평가)

  • Kim, Yoonkyung;Kim, Minseok;Jung, Kwansue
    • Proceedings of the Korea Water Resources Association Conference
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    • 2017.05a
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    • pp.200-200
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    • 2017
  • 강우에 의한 토양 침식 및 토사유츨량은 하천 및 유역환경관리 관점에서 가장 중요한 인자 중 하나로 보고되고 있으며, 다양한 분야에서 이에 대한 연구를 수행 중에 있다. 일반적으로 유역에서 발생한 토양침식 및 물의 이동에 의한 토사유출량을 해석하기 위해 SWAT 등과 같은 많은 모형이 적용되고 있지만, 대부분 농업지역에서 이용하는 수평형태의 수문학적 개념에 따른 overland flow 개념을 이용하고 있다. 하지만, 우리나라는 약 70% 이상이 산림으로 이루어진 지역으로 유역환경 해석에 있어 수평적인 개념과 함께 사면내에서 lateral flow와 같은 지표하 흐름의 이동에 관한 개념 역시 필요하지만, 이의 영향에 대한 관련 연구는 부족하다. 최근 수문학의 발달과 더불어 수평적인 개념을 탈피한 사면수문학 개념이 전 세계적으로 발달하고 있으며, 많은 발전을 이루고 있다. 이를 통해 GIS를 기반으로 물리학기반의 GeoWEPP 모형이 미국을 중심으로 개발되었고, 이에 대한 많은 적용 및 평가가 이루어지고 있다. 본 연구에서는 전 세계적으로 평가받고 있는 process 기반의 SWAT 모형과 사면수문학 개념을 반영한 물리학기반의 GeoWEPP 모형을 이용하였다. 이 두 모형은 강우, 지형, 토양도, 토지피 복도 등 두 모형의 입력자료 역시 거의 동일하게 구성되어 있으며, 같은 FORTRAN CODE 및 ArcGIS에서 운영될 수 있도록 이루어져 있어 비교 분석하기 원활하다. 모형의 적용은 매년 심각한 조류가 발생하는 대청호 지류인 소옥천 유역내 중하류에 위치한 옥각교에서 관측된 모니터링 자료(토사유출량과 유출량)를 이용하여 모형의 정확성을 평가 후, 사면수문학 개념의 적용성에 대해 논하였다. 각각의 모형의 결과에 대한 정확성 평가는, Nash-Sutcliffee를 이용하여 실시하였다.

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Mineralogical Characteristics of the Noro and Miag Series Soils Developed on the Cinder Cones in Jeju Island (제주도(濟州道) 산록(山麓)의 분석구(噴石丘)에서 발달(發達)된 노로통과 미악통 토양(土壤)의 광물학적(鑛物學的) 특성(特性))

  • Zhang, Yong-Seon;Kim, Yoo-Hak;Song, Kwan-Cheol;Kim, Sun-Kwan
    • Korean Journal of Soil Science and Fertilizer
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    • v.35 no.3
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    • pp.145-152
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    • 2002
  • The composition of primary minerals in the rocks and secondary minerals of clay fractions of the soil developed on the cinder cones in the foot of Halla Mt., Jeju Island was investigated. The effects of parent materials on the physico-chemical properties and mineralogical characteristics were evaluated by XRD, DTA with the chemical composition of $H^+$ saturated clays. The main rock-forming minerals of a residual cinder cones were plagioclase with subsidiary minerals of hematite, gibbsite and quartz in the red cinder cone and of augite, quartz, feldspars and olivine in black cinder cone. It is demonstrated that ignition loss and sesquioxides content were higher in the red cinder soil than black cinder, which was resulted in the intermittent eruption of volcanic activity. For the chemical analysis of whole soils, $SiO_2/Al_2O_3$ ratio was increased from 2 to 3, but Ignition loss is decreased and $K_2O$ content are very low with increasing the soil depth in regard to the composition and kinds of clay minerals. No clay formation from micas mineral were in volcanic ashes. Dominant clay minerals of the cinder cone soils as a black and red cinder cone soil were allophane with some quartz and feldspars, while vermiculite, illite, kaolin were coexisted as a subsidiary minerals. But the red cinder cones soils had more hematite and gibbsite of the clay fractions than the black soils with magnetite. The exothermic pick of DTA at about $660^{\circ}C$ for cinder cone soils might be corresponded the oxidation magnetite to hematite reation. With regarding to the compositions of mineral detected by X-ray diffractogram and the properties of minerals by D.T.A thermogram, the dominant clay mineral was allophane of the cinder cone soils with some ferrous compounds, red colour of the cinder cone soils which are originated in hematite.

Studies on Forest Soils in Korea (I) (한국(韓國)의 삼림토양(森林土壤)에 관(關)한 연구(硏究)(I))

  • Lee, Soo Wook
    • Journal of Korean Society of Forest Science
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    • v.47 no.1
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    • pp.52-61
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    • 1980
  • This study is carried out to learn the properties of forest soils in Korea and propose the reasonable management methods of forest land. Among 178 soil series surveyed until now in Korea forest soils include 64 series broken down according to the weathered products into 5 categories such as residual materials on mountain and hill, residual materials on rolling and hill, colluvial materials on local valley and fans, alluvial materials and volcanic ash soils. What discussed in this paper are classification system, parent rocks, texture class and drainage conditions of Korean forest soils. The characteristics of Korean forest soil properties classified in U.S.D.A. soil classification system are as follows: 1. Residual soils on mountain and hill (29 soil series) are almost Lithosols without any distinct soil profile development. They have loamy skeletal (11 series), coarse loamy (5 series), fine loamy (3 series), and fine clayey soils (3 series). Their drainage conditions are somewhat excessively drained in 16 series and well drained in 7 series. 2. Residual soils on rolling and hill (19 series) are Red-Yellow Podzolic soils with well developed soil profiles. They have coarse and fine loamy texture in 12 series and fine clayey texture in 5 series mostly with well drained condition. 3. Colluvial soils on local valley and fans (13 series) include mostly Regosols and some Red-Yellow Podzolic Soils and Acid Brown Forest Soils. They have loamy skeletal (4 series), coarse loamy (3 series), fine loamy (3 series), and fine clayey soils (2 series) with well drained condition. 4. Soil textures of weathered products of parent rocks are as follows: 1) Parent rocks producing coarse texture soils are rhyolite, granite gneiss, schist, shale, sandstone, siltstone, and conglomerate. 2) Parent rocks producing fine and heavy texture soils are limestone, basalt, gabbro, and andesite porphyry. 3) Granite is a parent rock producing various textured soils.

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Redox Characteristic and Evolution of a Fragipan of Gangreung Series Commonly Developed in Coastal Terraces (해성단구지에서 발달된 강릉통의 이쇄경반층(Btx) 토양의 산화.환원적 특성에 관한 연구)

  • Zhang, Yong-Seon;Moon, Yong-Hee;Sonn, Yeon-Kyu;Hyun, Byung-Keun;Park, Chan-Won;Yoon, Sung-Won
    • Economic and Environmental Geology
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    • v.45 no.2
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    • pp.137-144
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    • 2012
  • Soil pan typically presents the problems in soil water movement or in aeration which is not appropriate for a plant root growth, In this study physico-chemical characteristics of soils and micromorphological characteristic of clay accumulated zone were investigated to identify redox characteristic and evolution of a fragipan of Gangreung series commonly developed in coastal terraces. Gangreung series is classified as Aquic Fragiudalfs according to the USDA soil taxonomy. It is known that sedimentary ocean floor results in soil pan having parallel liner soil structure due to landscape evolution around 200 to 250 million years ago. it is considered that illite, kaolinite, and vermiculite are major clay minerals contained in a fragipan of Gangreung series. Mixed gray and reddish brown colored band around soil pores was found and would be the redoxmorphic features of fragipan. It is possibly due to accumulated illuvial clay and ferriargillans in soil pores and aggregates in reducing conditions eluding ferrous material. Therefore, mixed colored band around pores in soils of Gangreung series would be developed from the eluted ferrous materials which were accumulated in fragipan during the emerged land formation.