• Title/Summary/Keyword: Saturation

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Representative Physical and Chemical Properties of Korean Soils by the Results from Detailed Soil Survey (우리나라 토양(土壤)의 대표적(代表的)인 물리화학적(物理化學的) 특성(特性) (정밀토양조사결과(精密土壤調査結果)를 중심(中心)으로))

  • Hur, Bong-Koo;Jo, In-Sang;Min, Kyeong-Beom;Um, Ki-Tae
    • Korean Journal of Soil Science and Fertilizer
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    • v.17 no.4
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    • pp.330-336
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    • 1984
  • These studies were aimed to find out the representative values of physico-chemical properties in Korean soils and to serve the basic informations to improve the soil properties for increasing the soil productivity. By the results of detailed soil survey, 14 physico-chemical properties (soil texture, moisture characteristics, organic matter content etc) were collected from 315 series of soils except Cheju soils, computerized the simple mean and the distributed area by weighted mean values with grouping of land use, drainage class and soil type. The results were as follows; 1. Simple mean values within the efficient soil depth in whole country soils were clay 20.0%, organic matter 2.03% and CEC 10.3me/100g. But weighted mean values with land area belonged to the same soil series were clay 18.0%, OM 1.85% and CEC 8.6me/100g. 2. Mean values of paddy soils weighted by area were clay 19.7%, OM 2.0% and CEC 9.1me/100g but those of upland soils were 17.9%, 1.8% and 8.1me/100g and forest soils were 16.7%, 1.8% and 8.6me/100g respectively. 3. Weighted mean values of moderately well soils with covered area were clay 18.9%, organic matter 1.7%, CEC 8.4me/100g but those of imperfectly drained soils were 21.3%, 2.2% and 9.5me/100g, and those of poorly drained soils were 15.1%, 1.8% and 9.9me/100g respectivcly. 4. Simple mean and area weighted mean values of clay content, pH, organic matter contents, cation exchange capacity and base saturation were calculated by the types of paddy and upland.

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Risk Factor Analysis for $SaO_2$ Instability after Systemic-pulmonary Shunt (전신-폐 단락술 후 산소포화도의 불안정성의 위험인자 분석)

  • Jung Sung-Ho;Yun Sok-Won;Park Jung-Jun;Seo Dong-Man;Kim Young-Hwue;Ko Jae-Kon;Park In-Sook;Yun Tae-Jin
    • Journal of Chest Surgery
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    • v.38 no.4 s.249
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    • pp.277-283
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    • 2005
  • Arterial oxygen saturation $(SaO_2)$ instability frequently takes place after systemic-pulmonary shunt without shunt occlusion. We analyzed actual incidence and risk factors for $SaO_2$ instability after shunt operations, and possible mechanisms were speculated on. Material and Method: Ninety three patients, who underwent modified Blalock-Taussig shunt from January 1996 to December 2000, were enrolled in this study. Adequacy of shunt was verified in all patients, either by ensuing one ventricle or biventricular repair later on or by appropriate pulmonary artery growth on postoperative angiogram. Age, body weight, hemoglobin level at operation were 3 day to 36 years (median: 1.8 months), 2.5kg to 51kg (median: 4.1kg) and $10.7\~24.3$ gm/dL (median: 15.2 gm/dL) respectively. Preoperative diagnoses were functional single ventricle with pulmonary stenosis or atresia in 39, tetralogy of Fallot in 38 and pulmonary atresia with intact ventricular septum in 16. Pulmonary blood flow (PBF) was maintained pre-operatively by patent ductus or previous shunt in 64 and by forward flow through stenotic right ventricular outflow tract (RVOT) in 29. $SaO_2$ instability was defined as $SaO_2$ less than $50\%$ for more than 1 hour with neither anatomic obstruction of shunt nor respiratory problem. Result: 10 patients $(10.7\%)$ showed $SaO_2$ instability after shunt operation. After shunt occlusion was ruled out by echocardiogram, they received measures to lower pulmonary vascular resistance (PVR), which worked within a few hours in all patients. Risk factors for $SaO_2$ instability included older age at operation (p=0.039), lower preoperative $SaO_2$ (p=0.0001) and emergency operation (p=0.001). PBF through stenotic RVOT showed marginal statistical significance (p=0.065). Conclusion: $SaO_2$ instability occurs frequently after shunt operation, especially in patients with severe hypoxia pre-operatively or unstable clinical condition necessitating emergency operation. Temporary elevation of pulmonary vascular resistance is a possible mechanism in this specific clinical setting.

Surgical Outcome of Tetralogy of Fallot in Adolt -Implication of Preoperative Cyanosis- (수술 전 청색증 정도에 따른 성인 활로씨 4징증의 임상 양상)

  • Kim Sang-hwa;Park Soon-Ik;Park Jung-Jun;Song Hyun;Lee Jae-Won;Seo Dong-Man;Song Meong-Gun;Song Jong-Min;Kang Duck-Hyun;Song Jae-Kwan;Jang Wan-Sook;Kim Young-Hwue;Yun Tae-Jin
    • Journal of Chest Surgery
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    • v.38 no.4 s.249
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    • pp.271-276
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    • 2005
  • We analysed differences in operative methods and postoperative outcome according to the severity of preoperative cyanosis in adult ToF (Tetralogy of Fallot) patients. Material and Method: From August 1989 to June 2001, thirty three adult patients, 18 females and 15 males, underwent total correction for ToF. Their age ranged from 15 years to 54 years (median: 34). Patients were divided into 2 groups by preoperative $SaO_2$ (arterial oxygen saturation): group I$(n=cyanotic,\;SaO_2\;\geq94\%)$ and group II $(acyanotic,\; SaO_2\geq95%)$. Preoperative median hemoglobin level was higher in group I compared to group II (17.5 g/dl vs 15 g/dl). Postoperative follow-up duration ranged from 1 to 94 months (670 patient-month, median: 14 months), and 63 two-dimensional echocardiographic examinations were done during this period. Result: There were no early or late mortality. With regard to RVOT (right ventricular outflow tract) reconstruction, trans-annular patch and RV-PA extracardiac conduit were used in 7 and 3 patients respectively, and all of them belonged to group I. In group I, cardiopulmonary bypass time, aortic cross-clamping time, ICU day, hospital day were significantly longer than in group II, and postoperative inotropic support was significantly greater than in group II. There was no ventricular arrhythmia in both groups, and one patient in group I suffered from atrial arrhythmia, which was resolved spontaneously after tricuspid and pulmonary valve replacement. During follow-up periods, functional class, residual RVOT stenosis and pulmonary regurgitation, tricuspid regurgitation, occurrence of ventricular and atrial arrhythmias were comparable between two groups. Conclusion: In adult ToF patients with severe preoperative cyanosis, more aggressive RVOT reconstruction and careful postoperative care are mandatory. However intermediate-term outcome of this group of patients is comparable to the patients with minimal or no preoperative cyanosis.

Formation of Clay Minerals by Water-Rock Interaction in the Fracture of Gneiss (편마암 열극에서의 물-암석 상호반응에 의한 점토광물 생성)

  • Jeong, Chan-Ho;Kim, Soo-Jin;Koh, Yong-Kwon
    • Journal of the Mineralogical Society of Korea
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    • v.7 no.1
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    • pp.49-61
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    • 1994
  • As the groundwater flows along the fractures of crystalline rocks, it will be in contact with the fracture walls mostly coated by secondary minerals which are quite different form those of host rocks. The presence of fracture-filling minerals in crystalline rocks is important on the view point of radioactive waste disposal because of their great surface reactivity. The Surichi drill hole of 200 m in depth in the Yugu area composed mainly of Precambrian gneiss was selected to study the formation process of clay minerals on the fracture wall of gneiss, and their relation with present groundwater. The water-rock interaction in fractures resulted in the formation of gibbsite and clay minerals. They are formed by two different processes : (1) Incongruent dissolution of feldspar by groundwater diffused from a fracture path into rock matrix produced smectite and illite in situ, (2) on the wall of fracture, gibbsite, kaolinite, smectite and illite are formed by precipitation of dissolved species in groundwater. They show the paragenetic sequence such as gibbsite${\leftrightarrow}$kaolinite${\leftrightarrow}$smectite or illite. The paragenetic sequence of fracture-filling minerals was controlled by increase of pH of groundwater, decrease of fracture permeability by precipitation of fillings, and immobility of alkali or alkaline earths in groundwater. The groundwater from the Surichi borehole is a $Na-HCO_{3}$ type with pH range of 8.6-9.2. The sodium and bicarbonate in groundwater would be supplied by the dissolution of albite and calcite, respectively. The saturation index of groundwater and surface water calculated by WATEQ4F indicates that gibbsite and kaolinite are under precipitation to equilibrium state, and that smectite and illite are under equilibrium to redissolution environment. The stability relation of clay minerals in the $Na_{2}O-Al_{2}O_{3}-SiO_{2}-H_{2}O$ system shows that kaolinite is stable for all waters.

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A Study on Change in Cement Mortar Characteristics under Carbonation Based on Tests for Hydration and Porosity (수화물 및 공극률 관측 실험을 통한 시멘트모르타르의 탄산화 특성 변화에 대한 연구)

  • Kwon, Seung-Jun;Song, Ha-Won;Park, Sang-Soon
    • Journal of the Korea Concrete Institute
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    • v.19 no.5
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    • pp.613-621
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    • 2007
  • Due to the increasing significance of durability, much researches on carbonation, one of the major deterioration phenomena are carried out. However, conventional researches based on fully hardened concrete are focused on prediction of carbonation depth and they sometimes cause errors. In contrast with steel members, behaviors in early-aged concrete such as porosity and hydrates (calcium hydroxide) are very important and may be changed under carbonation process. Because transportation of deteriorating factors is mainly dependent on porosity and saturation, it is desirable to consider these changes in behaviors in early-aged concrete under carbonation for reasonable analysis of durability in long term exposure or combined deterioration. As for porosity, unless the decrease in $CO_2$ diffusion due to change in porosity is considered, the results from the prediction is overestimated. The carbonation depth and characteristics of pore water are mainly determined by amount of calcium hydroxide, and bound chloride content in carbonated concrete is also affected. So Analysis based on test for hydration and porosity is recently carried out for evaluation of carbonation characteristics. In this study, changes in porosity and hydrate $(Ca(OH)_2)$ under carbonation process are performed through the tests. Mercury Intrusion Porosimetry (MIP) for changed porosity, Thermogravimetric Analysis (TGA) for amount of $(Ca(OH)_2)$ are carried out respectively and analysis technique for porosity and hydrates under carbonation is developed utilizing modeling for behavior in early-aged concrete such as multi component hydration heat model (MCHHM) and micro pore structure formation model (MPSFM). The results from developed technique is in reasonable agreement with experimental data, respectively and they are evaluated to be used for analysis of chloride behavior in carbonated concrete.

A Study on Nutritional Anemia of Pre-school Children in Korea (한국 미취학 아동의 영양성 빈혈에 관한 연구)

  • Tchai, B.S.;Chu, D.S.
    • Journal of Nutrition and Health
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    • v.4 no.1
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    • pp.1-19
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    • 1971
  • Nutritional anemia is an important nutritional problem affecting large population groups in most developing countries. Nutritional anemia is caused by the absence of any dietary essential involed in hemoglobin formation or by poor absorption of these dietary components. The most likely causes are lack of dietary iron, and folate, vitamin $B_{12}$ and high qualify protein. Anemia is considered to be a late mainfeastation of nutritional deficiencies, and even mild anemia is not the earilest sign of such a deficiency. Therefore, the object of therapy is to correct underlying deficiency rather than merely its manifestation. Iron deficiency anemia is generally much the most common form of anemia. And it is very prevalent particularly in pregnant women and young children, especially under five year of life. According to the rapid growth rate of infants, dietary iron should he provided for infants over three months of age in adequate amounts for the synthesis of hemoglobin required by the increasing blood volume and for the demands of newly formed cells. The principal causes of iron deficiency anemia are an inadequate dietary iron content, interference with absorption of iron from the intestine, excessive losses of iron from the body, disturbance of iron metabolism by infection, and social and cultural environments. The present study is planned to obtain informations concerning nutritional anemia through anthropometric and biochemical determinations for the assessment of nutriture in pre-school children. Determination was taken in 226 pre-school children in ruraI arae in 1968, 122 pre-school children in 1970, and 1526 hospitalized pre-school children in 1970. The results of this study are as follows; (1) According to Iowa Malnutrition Borderline (85 percentile) for weight, the proportions of underweighed pre-school boys and girls in rural area were 47.2% and 46.2% in1968, and were 36.1% and 51.8% in 1970. According to Iowa Malnutrition Borderline for height, the proportions of underheight boys and girls in rural area were 30.5% and 33.7%, and were 26.2% and 21.8% in 1970. Malnutrition scores of underweight for height values of boys and girls in rural area were 19.3 and 17.3 in 1968, and the scores of boys and girls were 15.6 and 15.5 in 1970. (2) The mean hemoglobin values of boys and girls in rural area were $11.2{\pm}1.8g/100ml\;and\;11.4{\pm}1.6g/100ml$ in 1968. In 1970, the mean values of boys and girls in rural area were $11.3{\pm}1.3g/100ml\;and\;11.7{\pm}2.4g/100ml$. The mean hemoglobin values of hospitalized boys and girls were $11.9{\pm}2.2g/100ml\;and\;11.7{\pm}2.4g/100ml$ in 1970. It is found that 92 of 215 children (42.7%) in rural area had concentrations of hemoglobin less than 11.0g/100ml in 1968. In 1970, 55 of 121 children (45.4%) in rural area and 559 of 1526 hospitalized children (36.6%) had concentrations of hemoglobin less than 11.0g/100ml. (3) The mean hematocrit levels of hospitalized boys and girls were $35{\pm}26.8%\;and\;35.4{\pm}6.4%$ in 1970. And 443 of 1334 hospitalized children (33.2%) had hematocrit values below 33%. (4) The average mean corpuscular hemoglobin concentration levels of hospitalized boys and girls were $32.4{\pm}2.2\;and\;32.3{\pm}2.2$ in 1970. And 1016 of 1352 hospitalized children (75.1%) had the mean corpuscular hemoglobin values below 34. (5) The mean iron values of young children in rural area and hospitalized children were $62.0{\pm}6.3{\mu}g/100ml\;and\;60.7{\pm}22.8{\mu}g/100ml$. The proportions of anemia cases below $50{\mu}g/100ml$ in rural area was 37.9%, and 34.3% in hospitalized children. (6) The mean total iron binding capacity of young children in rural area was $376{\pm}57.88{\mu}g/100ml,\;and\;342.2{\pm}6.15{\mu}g/100ml$ in hospitalized children. (7) The average transferrin saturation percentage of young children in rural area was $16.9{\pm}4.7%,\;and\;18.0{\pm}8.4%$ in hospitalized children. The proportions of anemia cases below 15% of young chi1dren in rural area and hospitalized children were 48.3% and 41.2%. Therefore, authors wish to recommend that the following further studies should be undertaken: (1) Standardization of simplied laboratory examination of nutritional anemia. (2) The prevalence of nutritional anemia and the requirements of iron, folate, and vitamin $B_{12}$ of pre-school children. (3) The content and absorption of iron in Korean food. (4) The pathogenesis of nutritional anemia and prevention of parasitic disease. (5) Maternal health and nutrition education.

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Relationship between depression and resilience in adolescents with congenital heart disease (선천성심질환 청소년의 우울과 극복력의 관계분석)

  • Moon, Ju Ryoung;Jung, Yoen Yi;Huh, June;Kang, I-Seok;Park, Seung Woo;Yang, Ji-Hyuk;Jun, Tae-Gook;Kim, Myung Ja;Lee, Heung Jae
    • Clinical and Experimental Pediatrics
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    • v.49 no.5
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    • pp.523-528
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    • 2006
  • Purpose : The purpose of this study was to investigate the relationship between depression and resilience in adolescents with congenital heart disease(CHD) and to identify the variables associated with depression. Methods : The Resilience Scale(cronbach's ${\alpha}=0.92$), Children's Depression Inventory(cronbach's ${\alpha}=0.72$) and Maternal Behavior Research Instrument(cronbach's ${\alpha}=0.88$) were applied and analyzed to assess depression and resilience among 231 adolescents after surgery for CHD from three major cardiac centers in Korea. This group consist of 114 males and 117 females. The mean age was 15.8 years(range : 13-18 years). The clinical severity of illness was rated by CHD functional index and NYHA functional class. Results : The mean score for depression and resilience was 16.74(range : 0-49) and 115.84(range : 70-132) respectively. Depression was significantly related to age(r=0.25, P<0.001) and NYHA functional class(r=0.35, P<0.001), as well as being negatively correlated with oxygen saturation(r=-0.39, P<0.001), academic achievement(r=-0.41, P<0.001), parental attitude(r=-0.49, P<0.001) and resilience (r=-0.59, P<0.001). The results of multiple regression analysis showed that parental attitude(${\beta}=-0.48$, P<0.01) and resilience(${\beta}=-0.62$, P<0.01) were related to depression. Conclusion : This study demonstrated that adolescents with CHD had a higher resilience and were less depressed with an affectionate parent. With respect to medical and nursing intervention programs, it is essential to identify strengths of adolescents with CHD in order to increase their resilience. Additionally, it is also important that parenting and counseling programs be implemented for the parents of adolescents with CHD.

Hydrogeochemistry of Some Abandoned Metal Mine Creeks in the Hwanggangri Mining District, Korea : A Preliminary Study (황강리 광화대에 분포하는 일부 폐금속 광산수계의 수리지구화학적 특성 : 예비연구)

  • 이현구;이찬희;이종창
    • Journal of the Korean Society of Groundwater Environment
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    • v.6 no.4
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    • pp.194-205
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    • 1999
  • Hydrogeochemical variation and environmental isotope at the some abandoned metal mine (Sanggok, Keumsil, Jangpung and Samdeok) creeks of the Hwanggangri mining district were carried out based upon the physicochemical properties for surface water collected of February in 1998. Hydrogeochemical composition of the all water samples are characterized by the relatively significant enrichment of Ca$^{2}$, alkaline ions, N $O_3$$^{-}$ and Cl$^{-}$ in normal surface water, whereas the surface waters near the mining area are relatively enriched in Ca$^{2+$, Mg$^{2+}$, heavy metals. HC $O_3$$^{-}$ and S $O_4$$^{2-}$. Surface waters of the mining creek have low pH, high EC and extremely high concentrations of TDS compared with surface water of the non-mining creeks. The range of $\delta$D and $\delta$$^{18}$O values (SMOW) in the waters are shown in -65.0 to-71.2$\textperthousand$ and -9.1 to-10.2$\textperthousand$. The d($\delta$D-$\delta$$^{18}$O) value with those of water samples ranged from 7.3 to 10.9. These $\delta$D and $\delta$$^{18/}$ of the acid mine water are more heavy values than those of surface water. The values have revealed the positive correlation between isotopic compositions and major elements, because those $\delta$D and $\delta$$^{18}$O values increase with increasing TDS. HC $O_3$$^{-}$ , S $O_4$$^{2-}$ and Ca$^{2+}$ concentration. Using WATEQ4F, saturation index of albite calcite, dolomite and mostly clay minerals in water of the mining area show undersaturated and progressively evolved toward the equilibrium condition due to fresh water mixing, however, surface waters of the non-mining area are nearly saturated and/or supersaturated. Geochemical modeling showed that mostly toxic heavy metals within water in the mining creek may exist largely in the from of metal-sulfate (MS $O_4$$^{2-}$), free metal (M$^{2+}$/), C $O_3$$^{-}$ and/or OH$^{-}$ complex ions. Based on the geology, water chemistry and environmental istopic data the water compositions from the Sanggok and Keumsil mine creek (consist mainly of Cambro-Ordovician carbonate rocks of the Cho-seon Supergroup) show higher PH, Ca$^{2+}$, Mg$^{2+}$ , HC $O_3$$^{-}$ and more heavy $\delta$D and $\delta$$^{18}$O values than those from the Jangpung and Samdeok mine creek (consist of age -unknown metasedimentary rocks of the Ogcheon Supergroup and/or Jurassic grani-toids), but each of these waters represents a similar hydrogeochemical evolution path by the mine water mixing.

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A Study on the Characteristics of a Reclaimed Marine Soils (Gupo Series) distributed on the Southern Coastal Area of Korea (우리나라 남해안(南海岸)에 분포(分布)된 간척지(干拓地) 토양(土壤)의 특성(特性)에 관(關)한 조사연구(調査硏究)(구포통(鳩浦統)에 관(關)하여))

  • Juug, Yeon-Tae;Um, Ki-Tae;Shin, Yong-Hwa
    • Korean Journal of Soil Science and Fertilizer
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    • v.9 no.2
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    • pp.99-105
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    • 1976
  • After investigation of soil characteristics the properties of a reclaimed marine soil (Gupo series) distributed along the southern coastal areas of Korea are summarized as follows: 1. Gupo soils distributed in the southern Ria coastal area are derived from rolling to hilly materials and are poorly sorted with less influences of river fluvial action. These soils have high content of sand compared with the broad fluvio-marine soils in the western coastal areas. 2. The morphological features of the poorly drained Gupo soils are greyish brown sandy loam with a few yellowish mottles in the surface horizon and are grey sandy loam with a few gravel in the sub-strata. The ground water table remains around 10-30cm below the surface. These soils, recently reclaimed younger deposits, do not show any evidence of illuviation. 3. The "n" value (about 0.8) of the Gupo soils indicates physically unripened soils. 4. pH value of these soils shows more than 8.0 throughout the profile. Organic matter contents are extremely low (around 0.5%) except 1.2 percent in the surface horizon. C.E.C. ranges from 7 to 9m.e/100g which is lower than average in the country. The ratios of extractable cations such as Ca, Mg, Na and K of the surface horizon are 20:7:4:1. Base saturation is more than 60%. Available phosphate content is very low that is less than 25 ppm. Electric conductivity of the soils at $25^{\circ}C$ ranges 7 to 12 mmhos/cm and increased with depth. 5. According to classification of soil based on physical ripening, the Gupo soils can be classified into "Unripe soils with half-ripe sub-soils". The soils could be classified into "Hydric Haplaquents" in the original of the 7th Approximation (1960), but into "Typic Haplaqents in the supplement of 7th approximation which the physical ripening condition is not clearly expressed. Soil Taxonomy, apparently the final version of the 7th approximation, defines the soils as "Haplic Hydraquents" that clearly show the condition of physical ripening as well as other properties. Other several classification systems applied do not describe physical ripening condition of the soils.

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Distribution of Potassium Fractions and Soil Parameters Related to the Potassium Availability of Upland Soils (밭토양(土壤)의 칼륨형태별(形態別) 함량분포(含量分布) 및 칼륨비옥도(肥沃度) 관련지표(關聯指標))

  • Park, Yang-Ho;Ryu, In-Soo
    • Korean Journal of Soil Science and Fertilizer
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    • v.27 no.3
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    • pp.179-188
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    • 1994
  • This study was conducted to investigate the distribution of potassium fractions and to establish the soil chemical indices for assessing potassium availability in upland soil. Soil samples were collected from 66 vegetable crop fields of Chungbuk Jungweon, Jeonbuk Imsil and Kyengbuk Euiseong and these samples were analyzed water soluble(W. S. -K), exchangeable(Exch. -K) and nonexchangeable potassium(Nonex. -K). The distribution of potassium fractions was examined for soils having different physico-chemical properties and compared with the soil parameters related to the potassium availability. 1. The distribution ranges of W.S.-K, Exch.-K and Nonex.-K were 0.07~1.42, 0.27~2.30, and 0.84~4.74me/100g, and average contents of relevent fractions were 0.40, 1.03 and 2.37me/100g respectively. 2. Contents of W.S.-K and Exch.-K were decreased with increasing soil pH, CEC, Exch. Ca and Exch. Mg contents but Nonex. -K showed a low correlationship with these factors. 3. Exch.-K content slightly inereased with increasing clay content, while W.S.-K and Nonex. -K contents were grandually decreased with clay contents. 4. The relationship between W.S.-K and Exch.-K was significant and W.S.-K was released from soil at 0.23me/100g content of Exch.-K 5. Contents of W.S-K and Exch.-K showed high correlationship with soil chemical parameters such as ratio of exchangeable cations(K/Ca+Mg), ratio of exchangeable cation equivalent[$K/{\sqrt{Ca+Mg}}:(me/100g)^{1/2}$], potassium exchangeable free energy(${\Delta}F=RT$ 1n $K/{\sqrt{Ca+Mg}}$ : calories/mole) and saturation percentage of potassium($Exch.K/CEC{\times}100$), and these factors were considered to be good parameters for assessing soil potassium availability.

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