• Title/Summary/Keyword: Silt and clay

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Genesis and Characteristics of the Soil Clay Minerals Derived from Major Parent Rocks in Korea II. Physical and Chemical Properties of the Whole Soils (한국(韓國)의 주요(主要) 모암(母岩)에서 발달(發達)된 토양점토광물(土壤粘土鑛物)의 특성(特性)과 생성학적(生成學的) 연구(硏究) II. 토양(土壤)의 이화학적(理化學的) 특성(特性))

  • Um, Myung-Ho;Kim, Tai-Soon
    • Korean Journal of Soil Science and Fertilizer
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    • v.24 no.2
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    • pp.79-85
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    • 1991
  • This study reports on the physical and chemical properties of the whole soils (<2mm) derived from five major rocks of granite, granite-gneiss, limestone, shale, and basalt in Korea. The properties were considered from the kind and frequency distribution of rock-forming minerals in the parent rocks. In particle size distribution, sand fractions were high in the soils from granite-gneiss, silt fractions mainly, in the residual soils from limestone, shale, and basalt. And clay fractions were particularly high in the colluvial soil from limestone and the old alluvial soil from basalt. pH, extractable Ca and Mg, and cation exchange capacity of the soils derived from limestone might be considered to be high due to the presence of sand and/or silt-sized calcite and dolomite inherited from the parent rocks. However, the soils derived from granite and granite-gneiss, being abundant in feldspars, quartz, and micas, showed a tendency to the contrary. A soil from shale composing of high quartz tended to have pH. extractable Ca, base saturation, and low exchangeable Al. In total element analysis, the soils derived from parent rocks with high contents of (i) orthoclase and micas, (ii) biotite, primary chlorite, and augite, and (iii) carbonate minerals and plagioclase as a rock-forming mineral showed a tendency to decrease the contents of $K_2O$, $Fe_2O_3$ and MgO, and CaO in comparison with those of their parent rocks.

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Nutrient Solute Transport during the Course of Freezing and Thawing of Soils in Korea (동결(凍結)과 해빙(解氷) 기간(期間)중 토양내(土壤內) 양분(養分) 용질(溶質)의 이동(移動))

  • Ha, Sng-Keun;Jung, Yeong-Sang;Lim, Hyung-Sik
    • Korean Journal of Soil Science and Fertilizer
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    • v.28 no.2
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    • pp.135-144
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    • 1995
  • Understanding on nutrient solute movement during the course of freezing and thawing was attempted through laboratory and field obsevations. Small sectioned tubes with 5cm inner diameter, 0.2cm thick and 1cm long were connected to 30cm long soil columns for laboratory study. The columns were filled with soil, and treated with 20mmol/kg $KNO_3$ for upper 5cm. The upper end was set in the freezing section, and the lower end was set in the refrigerating section of a refrigerator. Temperature was controlled at $-7({\pm}1)^{\circ}C$ and $1.5({\pm}1)^{\circ}C$, respectively. After top 5cm soil was frozen, the columns were sectioned, and analyzed for $NO_3^-$, $NH_4^+$ and $K^+$. For field study, the 20cm inner diameter and lm long soil columns were installed in Chuncheon and Daegwanryung, where the altitude was 74m and 840m, respectively. The soils used were silt loam and clay loam. The top 20cm soils were treated with 50mmol/kg as $KNO_3$. The soil columns were taken during winter freezing and after thawing. By laboratiry study, upward movement of $NO_3^-$ and $K^+$ during the course of freezing was confirmed. The upward movement of $K^+$ was, however, one fifth to one tenth of $NO_3^-$. The upward movement of inorganic nitrogen as well as laboratory during the course of freezing, but large amount of nitrogen was lost from the profile after thawing in early spring. Leached nitrogen from the upper 20cm to lower part was 17 to 24 percents. The maximum depth of leaching during the experiment was 50cm for all soils. The net loss of inorganic nitrogen from the whole profile ranged 8.7 to 39.5 percents. The net loss was greater in Daegwanryung where temperature was lower and snowfall was larger than Chuncheon, and the loss was greater from the silt loam soil than clay loam soil of which percolation rate was small. The results implied that reasons for nitrogen loss during the winter might include surface washing by snow melt as well as leaching and denitrification.

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A Study on the Full-scale Soil Washing Process Improved by Multi-stage Continuous Desorption and Agitational Desorption Techniques to Remediate Petroleum-contaminated Soils (현장규모의 유류오염토양 세척공법에 다단연속탈착 및 교반탈착기법을 이용한 세척공정 성능향상에 관한 연구)

  • Seo, Yong-Sik;Choi, Sang-Il;Jang, Min
    • Journal of Soil and Groundwater Environment
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    • v.13 no.5
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    • pp.81-87
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    • 2008
  • In accompany with the transfer of US army bases, recent surveys reported serious contamination of soils by the release of petroleum from storage facilities and heavy metals accumulated in rifle-ranges. These problems have made an increased concerns of cleanup technology for contaminated soils. In this study, a full-scale soil washing process improved by multistage continuous desorption and agitational desorption techniques was examined for petroleum-contaminated soils obtained from three different remedial sites that contained 29.3, 16.6, and 7.8% of silt and clay, respectively. The initial concentrations of total petroleum hydrocarbon (TPH) were 5,183, 2,560, and 4,860 mg/kg for each soil. Pure water was applied to operate washing process, in which water used for washing process was recycled 100% for over 6 months. The results of full-scale washing tests showed that the TPH concentrations for soils (> 3.0 mm) were 50${\sim}$356 mg/kg (85.2${\sim}$98.2% removal rates), regardless of the contents of silt and clay from in A, B and C soil, when the soils were washed at 3.0 kg/$cm^2$ of injection pressure with the method of wet particle separation. Based on the initial TPH concentration, the TPH removal rates for each site were 85.2, 98.2 and 89.9%. For soils in the range of 3.0${\sim}$0.075 mm, the application of first-stage desorption technique as a physical method resulted 834, 1,110, and 1,460 mg/kg of TPH concentrations for each soil, also additional multi-stage continuous desorption reduced the TPH concentration to 330, 385, and 245 mg/kg that were equivalent to 92.4, 90.6, and 90.1% removal rates, respectively. The result of multi-stage continuous desorption for fine soil (0.075${\sim}$0.053 mm) were 791, 885, and 1,560 mg/kg, and additional agitation desorption showed 428, 440, and, 358 mg/kg of TPH concentrations. Compared with initial concentration, the removal rates were 92.0, 93.9 and 92.9%, respectively. These results implied we could apply strategic process of soil washing for varies types of contaminated soils to meet the regulatory limit of TPH.

Influence of Environmental Characteristics on the Community Structure of Benthic Macroinvertebrates in Stream-type Waterways Constructed at Upper Reaches of Guem River (금강 상류 구간 내 샛강형 수로의 서식환경 특성이 저서성 대형무척추동물 군집 구조에 미치는 영향)

  • Son, Se-Hwan;Choi, Jong-Yun
    • Korean Journal of Ecology and Environment
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    • v.54 no.1
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    • pp.24-38
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    • 2021
  • Microhabitat In the upper stream is created by various environment variables such as the bottom substrate and the physicochemical factors, and may influence the distribution of benthic macroinvertebrates. We investigated the bottom substrate and environmental variables influencing the distribution of benthic macroinvertebrate in 26 stream-type waterways established at upper reaches of Geum River. During study period, total 85 families, 160 species, 9305 individuals of benthic macroinvertebrates were recorded. The stream-type waterways, where the bottom substrates consist mainly of pebble (16~64 mm) and cobble (64~256 mm) or with rapid water velocity (more than 0.2 m/s) and high dissolved oxygen (more than 120%), were supported by high species diversity of benthic macroinvertebrate. Hierological cluster analysis and the nonparametric multidimensional scale (NMDS) divided 26 stream-type waterways into a total of three clusters. In Cluster 1, the invertebrate species, such as Branchiura sowerbyi, Cloeon dipterum, Ischnura asiatica, Paracercion calamorum, and Radix auricularia, closely related to aquatic macrophytes, and Chironomidae spp., Limnodrilus gotoi, and Tanypodinae sp. were abundant in waterways, with high coverage of silt and clay as well as high turbidity and total nitrogen. The benthic macroinvertebrate species (Cheumatopsyche brevilineata, Drunella ishiyamana, Dugesia japonica, Ephemera orientalis, Gumaga KUa, Macrostemum radiatum, Potamanthus formosus, Semisulcospira libertine, Stenelmis vulgaris, and Teloganopsis punctisetae) included in Cluster 2 were dominated in sites with high cover rates of pebble and gravel. Cluster 3 was predominantly covered by the Cobbles, was supported by Simulium sp. Such a clear distinction in the study sites means that each stream-type waterways is governed by a clear habitat environment. In the case of some sites with low species diversity, improvement measures are required to restore nature, such as improving the function of inflows and outflows, creating meandering channel, and inducing the settlement of littoral vegetation.

Sedimentary facies and micropaleontological study of tidal sediments off the Mankyung-Dongjin River estuary, west coast of Korea. (한국 서해 만경강-동진강 하구역 및 연안역 조간대 퇴적층의 퇴적상과 미고생물학 적 연구)

  • 이영길;박용안
    • 한국해양학회지
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    • v.30 no.2
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    • pp.77-90
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    • 1995
  • The sedimentary environments and biostratigrapy of the tidal sediments off the Mankyung-Dongjin River estuary were studied based on sedimentary facies and diatom assemblage analysis. Sediment facies from the five vibracores are mainly clay, silt, and sand facies. The clay and silty sediment facies are more dominant than the sandy facies, and contain diatom frustules. The frequency of the diatom frustules are rate to common, but not found in sandy sediment facies. Bigeneric structures such as burrow and non-bigeneric primary sedimentary structures such as laminated sand and mud or silt and mud couplets, flaser bedding, ripple-cross lamination are found in several stratigraphic levels of the sedimentary sequences. A total of 219 species and varieties, belonging to 61 genera has been identified in the present study. Among them, paralia sulcata is the most abundant species about 30 to 50% of the total diatom frustules. Another predominant species are Cyclotella striata. Thalassionema nitzschioides. Actinoptychus undulatus. Delphineis surirella, Raphoneis amphiceros. Most of the diatoms occurred in this study area are marine, marine-brackish water, and brackish water species, and are benthic and tychopelagic or meroplanktonic species. Also, most of the species are coastal to littoral and littoral to inner neritic species. The occurrences of freshwater species, about 1 to 5% is higher than that of the Namyang Bay tidal sediments. The ecological properties of the diatoms occurred in the study area and primary sedimentary structure such as flaser bedding ripple cross bedding indicate that the deposits are formed under coastal or littoral to subeditorial environments such as tidal zone which was subjected to the influenced of stream water and was more strongly influenced by temperate to warm water than cold water. The sedimentary environments have not been changed distinctively during the time of deposition. The vertical distribution pattern of diatoms in the study area is studied by Q-mode cluster Analysis using spss/pc+ (ver.4.0). The results show that the three cores (GE-3, GE-11, GE-12) are divided into two diatom assemblages, respectively. Biostratigraphic correlation using the data of Q-mode Cluster Analysis are attempt in this study.

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진해만 안골 바지락 양식장 대형저서동물 군집의 구조

  • Park Yeong Min;Yun Byeong Seon;Kim Gu Hwan;Yun Seong Gyu
    • Proceedings of the Korea Society of Environmental Biology Conference
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    • 2003.11a
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    • pp.92-97
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    • 2003
  • Community structure of macrobenthos was studied on Angol clam farming ground of Chinhae Bay in the southern coast of Korea. Macrobenthos samples were collected monthly using a quadrate at each station from March 1998. Macrobenthos samples were seived by 1.0mm mesh seive. Mean grain size was 0.267 mm. A total of 111 macrobenthos species were sampled with a mean density of 1,651ind/m$^2$and biomass of 1466.7wwt.g/m$^2$. Annelida was density-dominant faunal group with a mean density of 818ind/m$^2$, comprising of 49.6% of the total density of the macrobenthos. It was followed by Mollusca with 660ind/m$^2$(40.0%). Mollusca was biomass-dominant faunal group. Major dominant species in the number of individual were Ruditapes philippinarum (375ind/m$^2$), Batillaria cumingi (208ind/m$^2$), Cirrformia tentaculata (167ind/m$^2$), Ceratonereis erithraeensis (151ind/m$^2$), Capitella capitata (111ind/m$^2$) and Sigambra tentaculata (91ind/m$^2$). Major dominant species in the biomass were Ruditapes philippinarum (1156.6wwt.g/m$^2$), Batillaria cumingi (111.0wwt.g/m$^2$) and Cyclina sinenis (106.2wwt.g/m$^2$). The species diversity was increased gradually during the study period. Increasing of species diversity was due to not only increasing of number of species but also decreasing of dominance of some polycheates. Contents of silt-clay was increased gradually in the intertidal zone.

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Hydrodynamic Dispersion Characteristics of Multi-soil Layer from a Field Tracer Test and Laboratory Column Experiments (현장추적자시험과 실내주상실험을 이용한 복합토양층의 수리분산특성 연구)

  • Kang, Dong-Hwan;Yang, Sung-Il;Kim, Tae-Yeong;Kim, Sung-Soo;Chung, Sang-Yong
    • Journal of Soil and Groundwater Environment
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    • v.13 no.4
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    • pp.1-7
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    • 2008
  • This study analyzed for hydrodynamic dispersion characteristics of multi-soil layer (Silt and clay, Find sand, Coarse sand), data of a field tracer test on the multi-soil layer and data of laboratory column experiments on the samples on each soil layers. Through the analysis of permeability and flow, MS (Silt and clay) and FS (Fine sand), which were low effective porosity, were higher average linear velocity while CS (Coarse sand), which was high effective porosity, was higher hydraulic conductivity. Hydraulic conductivity function based on average soil particle diameter was assumed Y=$3.49{\times}10^{-8}e^{15320x}$ and coefficient of determination was 0.90. Average linear velocity function based on average soil particle diameter was assumed Y=$1.88{\times}10^{-7}e^{11459x}$ and coefficient of determination was 0.81. Longitudinal dispersivity function based on average soil particle diameter was Y = 0.00256$e^{5971x}$ and coefficient of determination was 0.98. According to the linear regression analysis of average linear velocity and longitudinal dispersivity, assumed function was Y = 21.7527x + 0.0063, and coefficient of determination was 0.9979. The ratio of field scale/laboratory scale was 54.09, it exhibited scale-dependent effect of hydrodynamic dispersion. Field longitudinal dispersivity (1.39m) was 7.47 times as higher than longitudinal dispersivity estimated by the methods of Xu and Eckstein (1995). Hydrodynamic dispersion on CS layer was occurred mainly by diffusion flow in the test aquifer.

Physico-Chemical Properties of Rainfall Interception Culture and Open Field Culture Soils of Rubus sp. In Gochang-gun, Jeollabuk-do (고창지역 복분자 비가림하우스 토양과 노지토양의 물리·화학적 특성)

  • Chung, Byung-Yeoup;Lee, Kang-Soo;Kim, Myung-Kon;Choi, Young-Hee;Kim, Moo-Key;Cho, Jae-Young
    • Korean Journal of Soil Science and Fertilizer
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    • v.41 no.5
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    • pp.303-309
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    • 2008
  • The physico-chemical properties of the rainfall interception culture (85 sites) and the open field culture soils (85 sites) in the area of Gochang-gun, Jeollabuk-do were surveyed. Soil textural distribution of the rainfall interception culture and the open field culture soils was 74% and 64% for silt loam, 16% and 35% for loam, and 10% and 1% for clay, respectively. The percentage of aggregate rates was higher in the open field culture soils (60.06%) than rainfall interception culture soils (55.84%). Electrical conductivity, exchangeable cations, and anions in the rainfall interception culture soils were higher than those in open field soils. Specially, accumulated amount of anion in rainfall interception culture soils was remarkably higher 2~3 times than open field culture soils. The results from the analyses of rainfall interception culture soils suggested that the most critical problem is the salts accumulation caused by over-fertilization of chemical fertilizer and compost. Therefore, application rates of chemical fertilizer and compost should be controlled in order to conservation of soil and water for sustainable agriculture.

Spatial Variation Analysis of Soil Characteristics and Crop Growth accross the Land-partitioned Boundary I. Spatial Variation of Soil Physical Properties (구획경계선(區劃境界線)의 횡단면(橫斷面)에 따른 토양특성(土壤特性)과 작물생육(作物生育)에 관한 공간변이성(空間變異性) 분석(分析) 연구(硏究) I. 토양물리성(土壤物理性)의 공간변이성(空間變異性))

  • Park, Moo-Eon;Yoo, Sun-Ho
    • Korean Journal of Soil Science and Fertilizer
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    • v.22 no.3
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    • pp.163-172
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    • 1989
  • In order to study spatial variability of soil physical properties accross the land-partitioned boundary on Hwadong silt clay loam soil (Fine clayey, mixed, mesic family of Aquic Hapludalfs), all measured data were analyzed by means of kriging, fractile diagram, smooth frequency distribution, and autocorrelation. Sampling for soil particle size distribution analysis was made at 225 intersections of $15{\times}15$ grid with 10m interval. Field capacity, bulk density and saturated hydraulic conductivity were measured in situ at 594 intersections of $33{\times}18$ grid with 2.5m interval in only $6,000m^2$ reselected from $22,500m^2$ of sampling area for particle size distribution analysis. Sampled or measured soil depths were 0 to 10cm 25 to 35cm and 50 to 60cm at each intersections. The results are summarized as follows: 1. The coefficient of variance (CV) of various physical properties ranges from 4.8 to 128.8%. Saturated hydraulic conductivity is classified into the high variation group with CV greater than 100%, while the low variation group with CV smaller than 10% consists of bulk density. Other properties belong to the medium variation group with CV between 10 and 100%. 2. The appropriate number of soil samples for the determination of various physical properties with error smaller than 10% are calculated as one for bulk density, six for field moisture capacity, 16 for silt, 19 for clay, 69 for sand and 686 for saturated hydraulic conductivity. 3. Smooth frequency distribution and fractile diagram show that saturated hydraulic conductivity is in lognormal distribution while other physical properties are in normal distribution. 4. Serial correlation analysis reveals that the soil physical properties have spatial dependence between two nearest neighbouring grid points. Autocorrelation analysis of physical properties measured between the serial grid points in the direction of south to north following section boundary shows that the zone of influence showing stationarity ranges from 7.5 to 40m. In the direction of east to west across section boundary, the autocorrelogram of many physical properties shows peaks with the periodic interval of 30m, which are similar to the partitioned land width. This reveals that the land-partitioned boundary causes soil variability.

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Physico-chemical Characteristics of Soil in the Vicinity of King Sejong Station, King George Island, Antarctica (남극 킹조지섬 세종기지 주변지역 토양의 물리화학적 특성)

  • Choi, Ik-Won;Park, Yang-Ju;Seo, Dong-Cheol;Kang, Se-Won;Jeon, Weon-Tai;Kang, Ui-Gum;Sung, Hwan-Hoo;Hur, Tai-Young;Heo, Jong-Soo;Cho, Ju-Sik
    • Korean Journal of Soil Science and Fertilizer
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    • v.44 no.5
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    • pp.709-716
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    • 2011
  • In order to collect basic data of soil environment in the Vicinity of King Sejong Station, King George Island, Antarctica, the physico-chemical characteristics of soils were investigated. Soil samples were collected in Barton Peninsula from 13 sites according to direction from the Sejong Cape. Soils from 13 sites were divided into three groups. The sand percentage of soils were much higher as above 90% than silt and clay percentages of soils at the all sites. Soil texture was classified sandy (10 sites) and loamy sand (3 sites). In distribution characteristics at different soil particles according to direction, large particles ($>500{\mu}m$) were higher in the order of Group 1 (Marian cove coast regions) > Group 2 (Inland regions) > Group 3 (Maxwell bay coast regions). On the other hand, small particles ($<355{\mu}m$) were higher in the order of Group 3 > Group 2 > Group 1. Chemical characteristic of soils showed significant differences at different areas. pH ranged 4.5-6.7, showing it was slightly acid and EC ranged $0.06-0.16dS\;m^{-1}$. T-N, OM and T-C contents were high at #6, #8, #12 and #13 sites. T-P and P2O5 contents were high at #9 and #12 sites. The results of this study will be helpful to understand soil environment in the Antarctic Peninsula and surrounding islands.