• Title/Summary/Keyword: silicate

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Comparison of Hydrochemical Characteristics of Groundwater in the Southern Area and the Northwestern Area, Pusan (부산 남부지역 지하수와 서북부지역 지하수의 수리화학적 특성 비교)

  • 함세영;조명희;성익환;이병대;조병욱;심형수
    • Journal of the Korean Society of Groundwater Environment
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    • v.6 no.3
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    • pp.140-151
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    • 1999
  • Groundwater samples from the southern area composed of andesitic rocks and the northwestern area composed of granite in Pusan city, have been collected and analyzed. According to the Piper diagram. groundwater in the southern area belongs to Ca$\^$2+/-HCO$_3$$\^$-/ and Ca$\^$2+/-(Cl$\^$-/+SO$_4$$\^$2-/) types, and that in the northwestern area mostly belongs to Ca$\^$2+/-HCO$_3$$\^$-/ type and partly Na$\^$+/-HCO$_3$$\^$-/ type. Two factors (factor 1 and factor 2) were obtained from the result of the factor analysis in the southern area. Factor 1, consisting of Mg$\^$2+/, Ca$\^$2+/, Cl$\^$-/, SO$_4$$\^$2-/, NH$_4$$\^$+/, EC and NO$_3$$\^$-/ is represented by the dissolution of Ca-plagioclase and calcite, and the influence of anthropogenic sources. Factor 2, consisting of K$\^$+/, Na$\^$+/. SiO$_2$, SO$_4$$\^$2-/, and HCO$_3$$\^$-/ is mainly represented by the dissolution of feldspar. Three factors were obtained from the result of the factor analysis in the northwestern area Factor 1, consisting of Na$\^$+/, K$\^$+/, NH$_4$$\^$+/, Cl$\^$-/, SO$_4$$\^$2-/ and NO$_3$$\^$-/ explains dissolution of plagioclase and mica, the influence of anthropogenic sources and salt water. Factor 2, consisting of Ca$\^$2+/ and HCO$_3$$\^$-/ explains the dissolution of Ca-plagioclase. Factor 3, consisting of Mg$\^$2+/ and SiO$_2$, explains the dissolution of silicate minces. and contaminants. Based on the phase stability diagrams, groundwater both in the southern and in the northwestern area is mostly in equilibrium with kaolinite. Cl$\^$-/ with respect to Na$\^$+/, Ca$\^$2+/, Mg$\^$2+/, K$\^$+/, SO$_4$$\^$2-/ and HCO$_3$$\^$-/ indicates that both the northwestern area and the southern area are influenced by the salt water.

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Characterization of Iron Oxides in Soils of Cheju Island by Mössbauer Spectroscopy and Chemical Techniques (Mössbauer 분광법(分光法)과 선택적(選擇的) 추출방법(抽出方法)에 의한 제주도(濟州道) 토양(土壤)에서의 산화철(酸化鐵)의 특성(特性) 구명(究明))

  • Kang, Dong-Woo;Kim, Doo-Chul;Ko, Jeong-Dae;Hong, Sung-Rak;Song, Kwan-Cheol
    • Korean Journal of Soil Science and Fertilizer
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    • v.30 no.1
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    • pp.3-15
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    • 1997
  • Iron oxide compounds in 8 selected Cheju Island soil samples have been analized by X-ray fluorescence spectrometer(XRF), X-ray diffractometry(XRD), selected chemical techniques, and $M{\ddot{o}}ssbauer$ spectroscopy. The result of this analysis by XRF shows that the rate of quantity of $Fe_2O_3$ in 8 soil samples was from 8.03wt.%(Daejeong paddy soil) to 18.21wt.%(Songag soils). Songag, Heugag and Gueom soils were detected to have lower peaks of intensity of hematite by XRD. In addition, these soils were not detected to have hematite and goethite peaks. Ferrihydrite, which is a short-range-order mineral commonly present in volcanic ash soil, was not detected by XRD due to low concentration and/or poor cristallinity. Ferrihydrite contents estimated from Feo values were 8.8~35.2g/kg for volcanic ash soils and 0.85g/kg for the Daejeong soil. Most of the soil samples represented by the paramagnetic $Fe^{3+}$ doublet obtained from $M{\ddot{o}}ssbauer$ spectra at room temperature and 18K were considered to arise from the presence of ferrihydrite, superparamagnetic goethite, and silicate minerals. Also the paramagnetic $Fe^{2+}$ doublets are attributable to primary minerals such as olivine, illite, chlorite, augite, biotite, and hornblende. Goethite and hematite were identified as the dominant crystalline iron oxides in these soils from $M{\ddot{o}}ssbauer$ spectra obtained at room temperature and 18K. All the soil samples exhibited strong superparamagnetic relaxation. Collapse of the $M{\ddot{o}}ssbauer$ magnetic hyperfine splitting at room temperature was due to the small size(${\sim}180{\AA}$) of the oxide particles and/or Al-subsituted goethite.

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The Change of Physico-Chemical Properties of Paddy Soil in Reclaimed Tidal Land (간척지 논토양의 물리화학성 변동에 관한 연구)

  • Yang, Chang-Hyu;Yoo, Chul-Hyun;Jung, Ji-Ho;Kim, Byeong-Su;Park, Woo-Kyun;Ryu, Jin-Hee;Kim, Taek-kyum;Kim, Jae-Duk;Kim, Seong-Jo;Baek, Seung-Hwa
    • Korean Journal of Soil Science and Fertilizer
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    • v.41 no.2
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    • pp.94-102
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    • 2008
  • The physico-chemical properties of ten reclaimed saline soils in five soil series of west-south Korea were analyzed according to the years past after reclamation. The soil samples were collected at the same sites two times in 2000 and 2004. The physico-chemical properties in 2000 had been changed in 2004 as follows. Soil salinity was the highest in Podu and desalinization period was the shortest in Munpo and Yeompo. Seasonal ground water level were above 100 cm in all regions that were 30 years old reclaimed tidal land, which was the same results of normal paddy field. In the case of soil physical changes, bulk density increased in fine textured soil (Poseung and Podu) but decreased in coarse textured soil (Gwanghwal, Munpo, and Yeompo). Porosity decreased in fine textured soil(Poseung and Podu) but increased in coarse textured soil. These reason were as follows. Fine textured soil were increased in solid phase but decreased in liquid and gaseous phase. Coarse textured soil, Gwanghwal and Munpo except for Yempo, were increased in gaseous phase but decreased in solid and liquid phase. Yempo that have low water table level were increased in liquid phase but decreased in solid and gaseous phase. Soil hardness increased in 4 soil series except for Munpo. In the case of chemical property changes, although there were more or less difference, it showed decreasing tendencies. Soil pH, the content of organic matter, available phosphate, and available silicate of five soil series were decreased during the four years. The content of exchangeable cation also decreased except for magnesium.

The Effect of Lattice Topology on Benzyl Alcohol Adsorption on Kaolinite Surfaces: Quantum Chemical Calculations of Mulliken Charges and Magnetic Shielding Tensor (캐올리나이트 규산염 층과 벤질알코올의 반응에 대한 양자화학계산에서 결정학적 위상이 멀리켄 전하와 자기 차폐 텐서에 미치는 영향)

  • Lee, Bum-Han;Lee, Sung-Keun
    • Journal of the Mineralogical Society of Korea
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    • v.20 no.4
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    • pp.313-325
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    • 2007
  • In order to have better insights into adsorption of organic molecules on kaolinite surfaces, we performed quantum chemical calculations of interaction between three different model clusters of kaolinite siloxane surfaces and benzyl alcohol, with emphasis on the effect of size and lattice topology of the cluster on the variation of electron density and magnetic shielding tensor. Model cluster 1 is an ideal silicate tetrahedral surface that consists of 7 hexagonal rings, and model cluster 2 is composed of 7 ditrigonal siloxane rings with crystallographically distinct basal oxygen atoms in the cluster, and finally model cluster 3 has both tetrahedral and octahedral layers. The Mulliken charge analysis shows that siloxane surface of model cluster 3 undergoes the largest electron density transfer after the benzyl alcohol adsorption and that of model cluster 1 is apparently larger than that of model cluster 2. The difference of Mulliken charges of basal oxygen atoms before and after the adsorption is positively correlated with hydrogen bond strength. NMR chemical shielding tensor calculation of clusters without benryl alcohol shows that three different basal oxygen atoms (O3, O4, and O5) in model cluster 2 have the isotropic magnetic shielding tensor as $228.2{\pm}3.9,\;228.9{\pm}3.4,\;and\;222.3{\pm}3.0ppm$, respectively. After the adsorption, the difference of isotropic chemical shift varies from 1 to 5.5 ppm fer model cluster 1 and 2 while model cluster 2 apparently shows larger changes in isotropic chemical shift. The chemical shift of oxygen atoms is also positively correlated with electron density transfer. The current results show that the adsorption of benzyl alcohol on the kaolinite siloxane surfaces can largely be dominated by a weak hydrogen bonding and electrostatic force (charge-charge interaction) and demonstrate the importance of the cluster site and the lattice topology of surfaces on the adsorption behavior of the organic molecules on clay surfaces.

Hydrogeochemical Characterization of Groundwater in Jeju Island using Principal Component Analysis and Geostatistics (주성분분석과 지구통계법을 이용한 제주도 지하수의 수리지화학 특성 연구)

  • Ko Kyung-Seok;Kim Yongie;Koh Dong-Chan;Lee Kwang-Sik;Lee Seung-Gu;Kang Cheol-Hee;Seong Hyun-Jeong;Park Won-Bae
    • Economic and Environmental Geology
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    • v.38 no.4 s.173
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    • pp.435-450
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    • 2005
  • The purpose of the study is to analyze the hydrogeochemical characteristics by multivariate statistical method, to interpret the hydrogeochemical processes for the new variables calculated from principal components analysis (PCA), and to infer the groundwater flow and circulation mechanism by applying the geostatistical methods for each element and principal component. Chloride and nitrate are the most influencing components for groundwater quality, and the contents of $NO_3$ increased by the input of agricultural activities show the largest variation. The results of PCA, a multivariate statistical method, show that the first three principal components explain $73.9\%$ of the total variance. PC1 indicates the increase of dissolved ions, PC2 is related with the dissolution of carbonate minerals and nitrate contamination, and PC3 shows the effect of cation exchange process and silicate mineral dissolution. From the results of experimental semivariogram, the components of groundwater are divided into two groups: one group includes electrical conductivity (EC), Cl, Na, and $NO_3$, and the other includes $HCO_3,\;SiO_2,$ Ca, and Sr. The results for spatial distribution of groundwater components showed that EC, Cl, and Na increased with approaching the coastal line and nitrate has close relationship with the presence of agricultural land. These components are also correlated with the topographic features reflecting the groundwater recharge effect. The kriging analysis by using principal components shows that PC 1 has the different spatial distribution of Cl, Na, and EC, possibly due to the influence of pH, Ca, Sr, and $HCO_3$ for PC1. It was considered that the linear anomaly zone of PC2 in western area was caused by the dissolution of carbonate mineral. Consequently, the application of multivariate and geostatistical methods for groundwater in the study area is very useful for determining the quantitative analysis of water quality data and the characteristics of spatial distribution.

Seasonal Variation of Primary Producer Phytoplankton Community in the Vicinity of the Oyster Farming Area between Tongyeong-Saryang Island (통영-사량도 굴 양식장 주변 해역에서 일차 생산자 식물플랑크톤 군집의 계절적 변화)

  • Lim, Young Kyun;Baek, Seung Ho
    • Korean Journal of Environmental Biology
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    • v.35 no.4
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    • pp.492-500
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    • 2017
  • The purpose of this study was to investigate the seasonal distribution of phytoplankton as prey for oysters and to characterize the environmental factors controlling their abundance from June 2016 to May 2017, in the northeast coast between Tongyeong and Saryang Island, particularly for the oyster farming area. During the survey period, water temperature changed from $7.54^{\circ}C$ in February to $29.5^{\circ}C$ in August. The abnormal high temperature persisted during one month in August. Salinity was low due to summer rainfall and typhoon. The lowest level was 30.68 psu in September, and it peaked at 34.24 psu in May. The dissolved oxygen (DO) concentration ranged from $6.0-9.45mg\;L^{-1}$, and the DO concentration in the surface layer was like that in the bottom layers. The seasonal trends of pH were also like those of DO. The pH ranged from 7.91 to 8.50. Nitrate with nitrite, phosphate, and silicate concentrations ranged from $0.14{\mu}M$ to $7.66{\mu}M$, from $0.01{\mu}M$ to $4.16{\mu}M$, and from $0.27{\mu}M$ to $20.33{\mu}M$, respectively. The concentration of chlorophyll a (Chl. a) ranged from $0.37{\mu}g\;L^{-1}$ to $2.44{\mu}g\;L^{-1}$ in the surface layer. The annual average concentration was $1.26{\mu}g\;L^{-1}$. The annual mean phytoplankton community comprised Bacillariophyta (69%), Dinophyta (17%), and Cryptophyta (10%), respectively. Dinoflagellate Prorocentrum donghaiense in June was the most dominant at 90%. In the summer, diatom Chaetoceros decipiens, Rhizosolenia setigera and Pseudo-nitzschia delicatissima were dominant. These species shifted to diatom Chaetoceros spp. and Crytophyta species in autumn. In the winter, high densities of Skeletonema spp. and Eucampia zodiacus were maintained. Therefore, the researchers thought that the annual mean Chl. a concentration was relatively lower to sustain oyster feeding, implying that the prey organism (i.e., phytoplankton) was greatly controlled by continuous filter feeding behavior of oyster in the vicinity area of the oyster culture farm.

Effect of amendments and their causes of rice yield increase in ill drained paddy soil (습답(濕沓)에 대(對)한 개량제(改良劑)의 효과(效果)와 유효개량제(有效改良劑)의 수도증수원인(水稻增收原因)에 관(關)한 연구(硏究))

  • Park, Chon Suh;Song, Jae Ha;Kim, Yung Sup;Lee, Chung Young;Choh, Young Sun
    • Korean Journal of Soil Science and Fertilizer
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    • v.4 no.1
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    • pp.13-19
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    • 1971
  • In order to establish the method of improving ill drained paddy soil where the accumulation of absorption inhibitor is worried in the earlier stages of rice growth, proper soil is selected and an field experiment is designed having treatments such as lime materials, none sulfate fertilizers, boron and straw etc. The data of yield and plant analysis in different stages of rice growth is eveluated and discussed to obtain following summaries. (1) Significant yield increase was made by the treatment of lime materials such as slacked lime or wollastonite powder, materials inhibiting the activity of microorganisms such as boron and of none sulfate fertilizers lacking inhibitor producing sources. (2) The crop scientifice causes of decreasing yield are the decreasing the number of panicles per hill, grains per panicle and the weight of grains. (3) The plant nutritional causes of decreasing yield are the lowering of nitrogen content throughout the life, phosphate content since young premodia formation stage of plant and the decreased content of magnesium, calcium and silicate in straw at harvesting stage. (4) The causes of lowering the content of various elements in rice plant grown in ill drained paddy soil are suggested as root damage by producing and accumulating absorption inhibitors such as organic acids and hydrogen sulfide etc, from the following observed facts; (a) In young premodia formation stage, attaining to the maximum production and accumulation of absorption inhibitor, the phosphate accumulation in plant was smaller in the phosphate plots than without phosphate plots and much higher in the neutralized plots by adding lime materials. (b) In the plots of straw addition, the potassium content in plant at the young premodia formation stage is very low probabley due to root damage by absorption inhibitor produced from the process of straw decomposition but higher at the stage of harvesting probably due to the immetabolic negative absorption of damaged roots. (c) The effect of boron, known as the inhibitor of microorganism activity to decompose organic matter, is apparent. (d) The effect of nonsulfate fertilizer treatment, having no source of producing inhibitor such as hydrogen sulfide, was significant. (e) All the yield components, decided around the young premodia formation stage attaining to the maximum inhibitor concentration in soil and minimum root activity, are significantly decreased.

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Establishment on Fertilizer Recommendation and Soil Characteristics of Rice Paddy with Environment-friendly Cultivation (농가실천 친환경 벼재배 논의 토양특성 및 시비추천량)

  • Yang, Chang-Hyu;An, Seung-Hyun;Kim, Taek-Kyum;Kim, Sun;Baek, Nam-Hyun;Choi, Weon-Young;Lee, Jang-Hee;Jeong, Jae-Hyeok;Kim, Si-Ju
    • Korean Journal of Soil Science and Fertilizer
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    • v.44 no.3
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    • pp.347-352
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    • 2011
  • Environment-friendly agriculture (EFA) are aimed to reduce use of chemical inputs as possible the recycling of resources and the environment while preserving the local resources in the long term to ensure a constant productivity and profitability for producing safe food. This study was conducted to investigate characteristics on soil environment at paddy field of environment-friendly agriculture regions (EFARs) in Honam area. Survey point of EFARs Chungnam, Jeonbuk and Jeonnam, rice bran farming method in two districts, rice bran + snail farming method in eight districts, snail farming method in five districts and ducks farming method in three districts a total of 18 districts were selected. Annual of farming method, friendly-environment certification, amount of applied fertilizer, and history of cultivation to the farm household were surveyed. The content of available phosphate and silicate among the soil chemical properties in EFA paddy field were a little lower than optimum level, and those of agricultural methods fertilized with rice bran were a little lower than those of others. Hardness among the soil physical properties in EFA paddy field were a little lower than conventional practices, and that of agricultural methods fertilized with rice bran were a little lower than those of others. We showed fertilizer recommendation dose about soil nutritional shortages according to fertilization prescriptions index by crops.

Effect of Long-Term Annual Dressing of Organic Matter on Physico-Chemical Properties and Nitrogen Uptake in the Paddy Soil of Fluvio-Marine Deposit (하해혼성 평야지 논토양에서 유기물 장기 연용이 토양의 이화학적 특성 변화 및 질소 흡수에 미치는 영향)

  • Yang, Chang-Hyu;Jeong, Ji-Ho;Kim, Taek-Kyum;Kim, Sun;Baek, Nam-Hyun;Choi, Weon-Young;Kim, Young-Doo;Jung, Won-Kyo;Kim, Si-Ju
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.6
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    • pp.981-986
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    • 2010
  • This study was carried out to investigate the effects of fertilizer and organic resource annual dressing for 30 years of Jeonbug series (silt loam) on soil properties and rice N uptake in paddy field soil. In the study field, treatments including control (NPK), NPK+rice straw, NPK+rice straw compost and nitrogen fertilization levels at 0, 100, 150, 200, 250 kg $ha^{-1}$ have been imposed for 30 years. Soil hardness and bulk density decreased from 15.7 mm and 1.381 Mg $m^{-3}$ in the control to 12.5 mm and 1.244 Mg $m^{-3}$ in NPK+rice straw compost treatment, respectively, indicating improvement of soil physical conditions such as porosity. Co-application of straw compost with NPK also result in a better chemical properties than NPK alone as it increased available phosphate (from 96 to 133 mg $kg^{-1}$), available silicate (from 81 to 116 mg $kg^{-1}$), and cation exchange capacity (from 9.8 to 11.4 $cmol_c\;kg^{-1}$). Soil organic matter concentration of top soil (0 to 7.5 cm in depth) was higher in NPK+rice straw and NPK+rice straw compost than in control. Fertilizer N uptake amount was much higher in NPK+rice straw (nitrogen fertilization level; 250 kg $ha^{-1}$) and NPK+rice straw compost (nitrogen fertilization levels; 200, 250 kg $ha^{-1}$) plots compared to the control (nitrogen fertilization level; 100 kg $ha^{-1}$) plot. Nitrogen use efficiency was showed significantly high in the NPK+rice straw compost (nitrogen fertilization levels; 100, 150 kg $ha^{-1}$) plot compared to the control (nitrogen fertilization level; 100 kg $ha^{-1}$) plot. Therefore, it was suggested that application of organic inputs is helpful in improving soil fertility and physical conditions and thus in N uptake.

Soil Characteristic of Plow and Compaction Layer in Fluvio-marine Deposit Paddy Soil (하해혼성 충적층 논토양 작토층과 경반층의 토양특성)

  • Yang, Chang-Hyu;Kim, Taek-Kyum;Ryu, Jin-Hee;Kim, Jae-Duk;Jung, Kwang-Yong
    • Korean Journal of Soil Science and Fertilizer
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    • v.42 no.5
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    • pp.364-370
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    • 2009
  • This study was conducted to survey, analyze on the compaction layer and the plow layer at Jeonbug and Jisan series paddy soil, which is the representative soil in fluvio-marine and local alluvium, respectively. The depths of surface soil were 12.6 and 12.7 cm in Jeonbug and Jisan series, respectively. A plowing depth was 10.5 cm. The properties of compaction layer in two soil series were as follows. The hardness were $14.7kg\;cm^{-2}(25.3mm)$ and $8.7kg\;cm^{-2}(22.1mm)$ in Jeonbug and Jisan series, respectively. The thickness were 22.3 cm and 17.8 cm in Jeonbug and Jisan series, respectively. The depth of soil compaction, which means depth from surface, were 15 and 20 cm in Jeonbug and Jisan series, respectively. The relationship between the hardness of compaction layer and the depth of surface soil showed negative correlation, however relationship between the hardness and the thickness of compaction layer showed positive correlation. Soil temperature was lower in compaction layer than in plow layer. This temperature differences between compaction layer and plow layer were from 1.0 to $2.5^{\circ}C$ in Jeonbug series and from 0.7 to 2.1 in Jisan series. The soil physical properties of compaction layer were higher in bulk density and solid phase and lower in porosity and gaseous phase than those of plow layer in all soil series. The soil chemical properties of compaction layer were higher in pH, content of available silicate, exchangeable calcium and magnesium but lower in total nitrogen, content of organic matter and available phosphate than those of plow layer in all soil series. Cation exchangeable capacity and content of exchangeable potassium were similar between compaction layer and plow layer in Jeonbug series, however, in Jisan series these were lower in compaction layer than in plow layer. Elution amount of inorganic nitrogen were lower in compaction layer than in plow layer in all soil series. The content of soluble Fe and Mn were plenty in compaction layer compared with plow layer and these tendency was apparent in Jeonbug series. The water depth decrease were fast until the latter part of June, and were slow as $1{\sim}3mm\;day^{-1}$ for July and August, and were fast again from september. Rice roots distributions as each soil series and tillage method were 25 cm at rotary plowing in Jeonbug series, 30 cm at deep plowing in Jeonbug series, and 20 cm at tillage in Jisan series. Dry weight per m2 at heading stage were much in order of deep plowing in Jeonbug series, rotary plowing in Jeonbug series, and tillage in Jisan series.